- Email: [email protected]
Visual rehabilitation of aphakic children
VISUAL REHABILITATION
OF APHAKIC
23. Helveston EM, Saunders RA, Ellis FD: Unilateral cataracts in children. Ophlhalmic Szcrg 1 I: 102-108, 1980 24. Hiles DA, Walter PH: Visual results following infantile cataract surgery. Int Ophthdmol Clin 17:265-282, 1977 25. Hiles DA: Visual acuities of monocular IOL and non-IOL aphakic children. Ophthalmology 87:1296-1300, 1980 lens implantation in children with 26. Hiles DA: Intraocular monocular cataracts 1974-1983. Ophthalmology: 91: 1231. 1984 of pediatric aphakia. .4rrh 27. Hoyt CS: The optical correction Ophlhnlmol 104:6.i l-652, 1986 28. Hoyt CS, Nickle B: Aphakic cystoid macular edema. Occurrence in infants and children after transpupillary lensectomy and anterior vitrectomy..4rch Ophlhalmol100:746-749. 1982 29. Hubel DH, Wiesel TN: The period of susceptibility to the physiologic effects of unilateral eye closure in kittens.,] Phy\io/ 206:419, 1970 30. Jacobson SC, Mohindra 1, Held R: Development of visual acuity in infants with congenital cataracts. BrJ Ophlhalmol 65:1727-1735, 1981 3 1 Karr DJ, Scott WE: Visual acuity results following treatment of persistent hyperplastic primary vitreous. Arch Ophthalmol lOJ:662-667, 1986 32. Kelly Cc;, Keates RH, Lembach KG: Epikeratophakia for pediatric- aphakia. Arch Ofihthalmol 104-680, 1986 33. Kenyon K, Poise KA, Seger RG: Influence of wearing schedulc on extended-wear complications. Ophthalmology 93: 23 l-236, 1986 34. Kersley HJ, Kerr C, Pierce D: Hydrophilic lenses for “continuous-wear” in aphakia: Definitive fitting and the problems that occur. Rr J Ophthal 61:38&42, 1977 35. Kushnel- BJ: Visual results after surgery for monocular juvenile cataracts of undetermined onset. Am J Ophthalmol fO2:468-472, 1986 36. Leibowitz HM, Laing RA, Sandstrom MC: Continuous wear of hydrophilic contact lenses. ,4rch Ophthalmol 89~306-3 10, 1979 37. Leinfelder PJ: Amblyopia associated with congenital cataract. Am J Ophthalmol 55t527, 1963 3x. Maumenee AE: Symposium on congenital cataracts. Oph1hmlmoloRy 86: 1605, 1979 39. Moore d: The fitting of contact lenses in aphakic infants. ,/ ,-lm Optomrtnc A.\sn 56: 180-l 83, 1985 40. Morgan KS, Marvelli ‘Il., Ellis GS. Arffa RC: Epikeratophakia in children with traumatic cataracts.] Pedialr Ophthnlmol Slrahism~cs 23: 108, 1986 41. Morgan KS. Arffa KC, Marvelli TL, Verity SM: Five year followup of epikeratophakia in children. Ophthalmology 93.423, 1986 42. Morgan KS, Stephenson GS, McDonald MB, Kaufman HE: Epikeratophakia in children. Ophthalmology 91~780-78.1,
I984 43.
44.
371
CHILDREN
Morgan KS, Franklin KM: Oral fluorescein angioscopy in aphakic children. ,I Prdintr Ophthnlmol Strabismus 21.~33-36. I984 Nelson LB, Cutler SF, Calhoun JH, et al: Silsoft extended wear contact lenses in pediatrjc aphakia. Ophthalmology Y9:1.5”!?-1.531 _ . 1985.
45. 46. 47. 48.
49. 50. 51.
52.
53.
54.
55. 56. 57
58 59.
60.
61.
62. 63. 64. 65. 66.
Nelson LB: Diagnosis and management ofcataracts in infancy and childhood. Ophthalmic Surg 15:688-697, 1984 Parks MM, Hiles DA: Management of infantile cataracts. Am J Ophthalmol 63: IO, 1967 Parks MM: Visual results in aphakic children. ,~TNJ Ophlhalmol 94;441-449, 1982 Pierse D, Kersley HJ: Hydrophilic lenses for “continuouswear” in aphakia: Fitting at operation. H? ,/ Ophthnlmol 61:34-37. 1977 Poer DV, Helveston EM, Ellis FD: Aphakic cystoid macular edema in children. Arch Ophthalmol 99:249-252, 1981 Powers MK, Dobson V: Effect of focus on visual acuity of human infants. Vision Ke.\ 22:52 1, 1982 Pratt-Johnson JA, Tillson C: Visual results after removal of congenital cataracts before the age of 1 year. (:a?~,/ Ophthnla01 l&19-21, 1981 Pratt-Johnson JA, Tillson G: Hard contact lenses in the management of congenital cataracts../ P&alr Oph~hnlmd Slmhumu.s 2294-96, 1985 Robb KM, Mayer DL. Moore BD: Results of early treatment of unilateral congenital cataracts. 1 P&III. Ophlhahol 24:17X-181. 1987 Rogers CL, Tishler CL, Tsou BH, et al: Visual acuities in infants with congenital cataracts operated on prior to 6 months of age. Arrh Ophthalmol 99t999-1003. 19X1 Rogers CL: Extended wear silicone contact lenses in children with cataracts. Ophthalmo/og? 87:X67-870, 1980 Ryan SJ, Maumenee AE: Unilateral congenital cataracts and their management. Ophlhalmir Surg Y:35, 1977 Saunders RA, Ellis FD: Empirical fitting of hard contact lenses in infants and young child&. Ophthnlmolog? HX:lP7-130, 19x1 Schic HG: Aspiration of congenital or soft cataracts. A new technique. Am J Ophthalmol 50: 1048, 1960 Shaw EL, Gasset AR: Experience in the use of soft contact lenses for the correction of monocular and binocular aphakia. :lnn Ophthnlmol 5:937-943, 1973 Taylor D: Choice of surgical technique in management of congenital cataracts. Tmn\ Oph~hrdmol Sot C’K lOI: 14-l 17, 1981 .l‘aylor D, Vaegan, Morris JA, et al: Amblyopia m bilateral infantile and juvenile cataract. Relationship to timing of treatment. Trans Ophthalmol Sot UK 99:170-l 75. 1979 Vaegan TD: Critical period for deprivation amblyopia in children. Tmns Ophthalmol Sot L’K 99:432-439, 1979 Van Noorden GK: Stimulus deprivation amblyopia. Am ,/ Oph/hnlmol 924 16-42 1, 198 I Weissman B: Fitting aphakic children with rontart lenses.,/ .Am Oplom Asoc 51:235-237, 1983 Wiesel TN, Dubel DH: Extent of recovery from the effect of visual deprivation in kittens. J Nmirophysiol 2X: 1060, 1965 CViesel TN: Effects of monocular depl:ivation on the cat’s visual cortex. Tram ,4m Acarl Ophthalmol Otolqngol 75: 1 186. 1971
Reprint address: John D. Baker, M.D., Department thalmology, Children’s Hospital of Michigan, 3901 Blvd., Detroit, MI 48201.
III. Intraocular Lenses. DAVID A. HILES, M.D.,De artment of Ophthalmology, Pittsburgh School of Medicine, Pittsburgh, Penny Pvania While discussing options of aphakic optical devices prior to surgery, all rehabilitative modalities must be considered by the ophthalmologist and the child’s family. Glasses are useful for children with bilateral aphakia. While expensive, and applied as only part-time optics, they are noncontact and easily modified devices. They are not worn successfull)
of OphBeaubien
University of
by unilateral aphakes because of the associated anisometropia and anisokonia. No child in my experience, either with an infantile or acquired unilateral cataract, has been visually rehabilitated with unilatera1 aphakic spectacles. Contact lenses remain the preferred aphakic correction modality for most infants and children. Ker-
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BAKER, HILES,
1990
atometry and refraction are performed upon small children under the same general anesthesia as the cataract aspiration. The lenses are fitted upon the eye within the first few postoperative days or when the intraocular surgical inflammatory response has subsided. Lens modifications are made over the first three years of life to compensate for the rapid myopic shift of the infant apbakic eye.4a It became apparent early in my experience that the expense of contact lenses to many patients was great, the insertion and removal of the lens was often traumatic, the loss rate was often high, and wear and compliance decreased with time and with changes in the socioeconomic conditions within the family. I still recommend, however, that infants born with unilateral or bilateral cataracts be operated on within the first week(s) of life and be fitted with a contact lens followed by occlusion of the sound eye when appropriate. The implantation of a unilateral intraocular lens (IOL) in a child’s eye was first performed by Choyce’ in 1956 followed by Binkhorst in 1959.3 Controversy soon arose over IOL rehabilitation for children. Cataract surgery performed on pediatric patients differs from that performed on the adult.’ Pediatric ophthalmologists have been reluctant to implant lenses because of their fear of the longterm effects of an IOL in a child’s eye, and because of their hesitation to depart from the highly successful small incision cataract aspiration technique first advocated by Scheie in 1960.15 Ophthalmologists performing adult cataract extractions implant IOLs as a routine procedure and do not fear the larger incisions and complications associated with IOL insertion. However, these surgeons frequently overlook the complications of pediatric intraocular surgery and neglect the necessary optical, amblyopia and strabismus corrections necessary for children.*
Iedications for IOL Implantation There are two major indications for IOL implantation in children. The first, and most important, is to preserve vision and prevent amblyopia. The second is the preservation or development of fusion.6,‘7a Patients should be considered for IOL implantation if the parent or the child refuses contact lens wear, if the ophthalmologist deems that contact lens wear would not be successful due to patient or parent noncompliance, or if other social or economic factors preclude adequate contact lens follow-up.* IOL implantation should be confined to unilateral aphakic children because of the unknown very longterm effects of the presence of an IOL and its component materials in the human eye. In patients with bilateral cataracts and asymmetrical visual loss, IOL implantation into one eye is usually performed
MORGAN
after contact lens failure in order to improve that eye’s acuity. The visual results for these eyes are the same as for unilateral cataract eyes. If acuity fails in the fellow eye due to increasing density of that cataract, IOL implantation is not warranted and another contact lens should be tried or an epikeratophakia graft should be considered. INFANTILE
CATARACTS
Infantile cataracts are those occurring in children with a lens opacity present at birth or arising before the eighth birthday. Included here are familial or sporadic mutations, metabolic and syndrome-related cataracts, anterior PHPV, posterior lenticonus, and progressive late onset juvenile cataracts.6 Unilateral infantile cataract patients older than two to three years are IOL candidates. Children less than eight years of age in the amblyopia-forming age group require the additional therapeutic modality of amblyopia occlusion. Spectacles to correct residual optical errors, if necessary, are well tolerated and accepted by most children.’ IOLs have not been implanted in neonates because of prolific production of secondary membranes and synechiae formation. It may be these young eyes that will most benefit from IOL implantation techniques in the future, for very early IOL implantation may yet prove as surgically successful as has the neonatal removal of infantile cataracts. With neonatal IOL implantation the rapid myopic shift which occurs during the first years of life must be taken into consideration. TRAUMATIC
CATARACTS
Children with traumatic cataracts and cornea1 scars that preclude successful contact lens wear are also IOL candidates. Traumatic aphakic patients may be subdivided into those in the amblyopiaforming group up to eight years of age, and those beyond this age. Amblyopia occurs with traumatic cataracts and following surgery in young children. This is related to the age of the patient at the time of occlusion of the visual axis by the cataract and to the time elapsed before the eye is optically rehabilitated. The longer these intervals, the greater is the possibility of irreversible deprivation amblyopia. ‘“,‘4~‘8These patients may receive an IOL either as a primary procedure at the same surgery as repair of the globe and cataract extraction,‘0~‘4~‘s or secondarily following contact lens failure.6*‘0*‘4”8 More commonly, and more prudently, the IOL is implanted later, either with cataract surgery, or secondarily, after contact lens failure. Surgery should be deferred until the intraocular pressure and inflammation have returned to normal following trauma. Late cataract extraction and IOL implantation is performed when the lens has become
VISUAL REHABILITATION
OF APHAKIC
373
CHILDREN
opaque, visual fixation responses are decreased, or the corrected vision is 20/70 or less. A lens implant is a very satisfactory mode of aphakic correction in children over six years of age with traumatic cataracts. The IOL optics are crisp, clear and accurate, and vision rapidly returns with subsidence of the surgical trauma. If the eye is not severely damaged by cornea1 scars, glaucoma or posterior polar defects, visual restoration is excellent. Amblyopia therapy in amblyopia-prone patients and spectacle correction for all patients aids in the restoration of visual function. If strabismus develops, early surgery is indicated to restore a normal ocular alignment and secure the best possible peripheral, if not. central, fusion.
Contraindications to IOL Implantation Patients with microphthalmic eyes with corneas less than 10 millimeters in diameter should not receive IOLs because of insufficient space within the anterior chamber to assure that cornea1 endothelial touch will not occur during or following implantation. Patients with large central axial cornea1 scars continue to achieve poor postoperative visual results. Cornea1 grafting, while anatomically feasible, is not often visually successful in many young children. Eyes with congenital, familial or acquired aniridia following trauma have insufficient support systems for either an anterior chamber or iris-supported IOL. If the capsular bag and zonules are intact at the conclusion of cataract surgery, secure capsular fixation alone may be possible with a posterior chamber lens. Eyes with traumatic or syndrome-related dislocatkd lenses are not suitable for implantation because of their high incidence of retinal detachment and/or secondary glaucoma. Eyes with decreased endothelial cell counts following trauma or previous surgery should also be excluded. Eyes with infantile glaucoma also have been rejected, for they redevelop glaucoma, which is extremely difficult to control medically or surgically. 101,s should not be implanted into eyes with chronic intraocular inflammation, including the rubella syndrome, juvenile rheumatoid arthritis syndromes, toxocara canis, toxoplasmosis, pars planitis, or other chronic anterior or peripheral retinal inflammations. Late exacerbations of these inflammations may occur, which can be accompanied by synechiae formation and secondary glaucoma. Eyes with known retinal detachments, macular lesions, optic nerve defects or atrophy, or diabetes with progressive proliferative retinopathy are also not IOL canclidates.:
IOL Selection The selection of the IOL depends upon the need for fixation and the condition of the anterior seg-
ment related to immediate or previous ocular surgery or trauma and the age of the child at implantation. IRIS-FIXATED
IOLs
1 first selected the Binkhorst two-loop IOL based on the concept that firm iridocapsular adhesions formed by children would maintain secure and permanent IOL fixation. However, IOL dislocations did occur. Iris-suture lenses offered the additional advantage of a lens fixed in the pupillary space by iridocapsular adhesions, plus additional fixation supplied by the 10-O nylon iris suture. The small, lightweight lens does not encroach upon the anterior chamber angle or permit the haptic to become enmeshed within the capsular sac. The pupil may be dilated widely for retinal examination. The lens permits the eye to grow without affecting haptic placement, since neither the peripheral capsular bag, zonules, or angle are utilized for fixation, an important consideration in eyes of rapidly growing children.“,x However, corneat endothelial cell loss and cystoid macular edema have been observed from pseudophakodenesis, and the use of this type of lens has markedly decreased in recent years. Metal looped lenses and fixation devices were tried because the inert metal would not biodegrade with the passage of time. The heavy metal loops and clips led to iris sphincter erosion, pseudophakodenesis, continued cornea1 endotheliat cell toss leading to cornea1 edema, and an increase of cystoid macular edema. 1 no longer can recommend iris-fixation IOLS. ANTERIOR
CHAMBER
IOLs
As the lensectomy-vitrectomy cataract operation gained popularity among pediatric ophthatmologists, the secondary anterior chamber IOL offered the only possibility for IOL aphakic rehabilitation for these eyes. An IOL placed in front of the pupil should have minimal contact with the iris, avoid pupillary block, and permit adequate pupiltary dilation for examination of the retina and for secondary membrane surgery if required.’ Anterior chamber IOLs are indicated for children lacking posterior capsular support sufficient for a posterior chamber lens. This situation occurs in patients who have large posterior capsulectomies following lensectomy-anterior vitrectomy, or for those who have immobile, dilated pupils following trauma. Since the child’s eye is almost fully grown between three and six years of age, a lens with the potential for elongating slightly as the anterior segment of the eye completes its growth is ideal for this application. The need for secondary membrane surgery in these eyes is uncommon. If a membrane does occur, a surgical discission under the lens or
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1990
Nd : YAG laser capsulotomy is easily performed. I now recommend a flexible one-piece open looped PMMA primary anterior chamber intraocular lens for all contact lens-noncompliant children between three and six years ofage as either a primary or secondary IOL implantation, as well as for children over six years of age who receive secondary lens implantation. Several specific surgical recommendations are suggested for anterior chamber lens implantation. The lens should not be placed into an eye with vitreous protruding into the anterior chamber. A vitrector should be used to clear the visual axis of vitreous and other lens remnants prior to implantation. Healon@ is placed in the anterior chamber to protect the anterior iris surface from trauma and to reduce cornea1 endothelial cell loss during implantation. A Sheets lens glide is used to further protect the iris when the lens passes over its surface. After the lens is in place, the wound is closed with interrupted 9-O polygalactin sutures, and 4-mirror gonioscopy is performed to assure that the lens pods are in proper position in the anterior chamber angle. POSTERIOR
CHAMBER
IOLs
I prefer the posterior chamber lens for implantation in all children with otherwise normal anterior segments undergoing primary intraocular lens implantation. Based upon new data gathered from my series, I have established new guidelines for intraocular lens implantation in children.4”8 ” I now recommend that posterior chamber intraocular lenses be implanted in eyes of children six years of age and older, or in those younger children who are able to undergo Nd : YAG laser capsulotomies. Posterior chamber lenses are particularly useful for older children who have had normal eyes prior to the onset of the cataract. Postoperative rehabilitation is rapidly achieved with the restoration of normal vision using a high quality optical device. I prefer the Sinskey soft J loop lens design with lo-degree forward anterior angulation of the haptics. A posterior chamber lens is selected for primary implantation when the anterior segment of the eye is normal except for the cataract, and when the posterior capsule remains intact or has only a small central posterior capsulotomy without vitreous presentation following cataract aspiration. A secondary posterior chamber lens is implanted if the posterior capsule is intact, or if vitreous is not protruding through a previously created central capsulotomy, and if the peripheral posterior capsular membrane would support and adhere to the lens haptics. The exact position of the lens haptics cannot always be
BAKER, HILES, MORGAN determined because the space between the posterior capsule and the iris may be compressed due to the collapse of the child’s sclera producing forward vitreous pressure. At the conclusion of the procedure, all eyes with a posterior chamber lens receive a central posterior capsulotomy after the lens is in position and the eye has been closed. Posterior chamber lens candidates require meticulous attention to specific aspects of the cataract aspiration as well as the lens implantation. Healon@, rather than continuous irrigation, is used to reform the anterior chamber during the anterior capsulectomy. The phacoemulsifier is recommended to reduce the operative time of cataract aspiration to a minimum, thus decreasing trauma to the iris and preventing rupture of the posterior capsule. Anterior chamber irrigation is reduced during phacoemulsification to prevent iris prolapse and pigment epithelial loss. Such iris trauma in children induces synechiae formation between the iris and lens haptic or optic, leading to iris capture and IOL malposition. Anterior chamber Healon* and a Sheets lens glide facilitate implantation of the lens. Accurate loop placement is often impossible because of the collapsible nature of the child’s eye. In-the-bag loop placement frequently occurs with the inferior loop, but the superior loop is usually placed in the ciliary sulcus. Manipulation of the superior iris to implement loop placement is avoided, for this induces synechiae formation and iris capture. Additional trauma may occur to the iris pigment epithelium during rotation of the posterior chamber lens to a horizontal position. Primary posterior capsulotomies are routinely performed under the posterior chamber lenses at the conclusion of the procedure. It should be stressed, however, that even with a primary posterior capsulotomy, in 63% of our patients, the visual axis became re-occluded by secondary membranes, and required secondary capsulotomies. ” Secondary surgery required to create a posterior capsulotomy in these eyes is complicated by the position of the lens behind the iris. Even with the use of viscoelastic agents, there is a high risk of dislodging the lens during the discission operation by breaking the synechiae that secure it in place. If this occurs, vitreous may prolapse around the lens and into the anterior chamber, causing further lens malposition. Cornea1 endothelial cell loss may occur by lens optic touch if the anterior chamber should accidently collapse during the operation. Iris trauma may lead to further synechiae between it and the lens, inducing additional iris capture, lens tilt, or visual axis occlusion. Nd: YAG laser posterior capsulotomies may be accomplished in children over six years of age. This
VISUAL REHABILITATION
technique induces less trauma to the eye than an operative disc&ion, does not require general anesthesia, and may be repeated if additional capsular opacification occurs.‘” Patients younger than six years of age are generally poor candidates for Nd :YAG laser capsulotomy, as they are often frightened and become uncooperative. The operative risk for laser therapy is higher for them because the capsulotomy must be performed under general endotrachial anesthesia with the child placed in an upright position at the laser, which is often located outside of the operating room environment. Posterior chamber lens implantation is contraindicated as a secondary procedure unless an intact posterior capsule or adequate peripheral capsule is present to support the lens. In addition, sufficient iris and capsular synechiae formation to the haptics is required to prevent lens malposition; these synechiae frequently do not form and dislocation of the IOL occurs.” Iris synechiae to the posterior capsule, irregular fixed pupils, and collapse of the capsular bag with adhesions of the anterior and posterior capsule make identification of capsular clefts difficult, thus precluding secondary posterior chamber lens implantation into the eyes of most young children. Even though a primary posterior capsulotomy is always performed at the conclusion of the implantation procedure, anterior capsular epithelial cell metaplasia and proliferation often lead to thick, tough, dense, secondary membranes which re-ocelude the original posterior capsulotomy and induce haptic dislocation and superior iris capture. Apparently these cells utilize the intact formed anterior vitreous face of children, as well as the posterior surface of the IOL, as a scaffolding for cellular proliferation and migration which re-oceludes the clear visual axis created in the previously opened posterior capsule. This synechiae formation and lens capsular opacification precludes adequate pupillary dilatation for retinal examinations, and for visual development.
Intraocular
375
OF APHAKIC CHILDREN
Lens Power
The IOL powers are either emperically determined or are calculated from keratometric readings, A-scan axial lengths, anterior chamber depths and refractive errors. Hoffer” has described the dilemma of IOL power determination in children. An 101, may be selected to produce emmetropia at the time of implantation, but with growth ofthe eye, optical errors of increasing magnitude may occur. A second consideration is to replace the IOL in adulthood with an IOL of lesser power. This approach is particularly hazardous, for it requires a difficult secondary operative procedure to remove the IOL.
which is firmly fixed to the intraocular structures. The third suggestion is to implant an IOL of a power suitable for an adult, thus allowing the child to grow toward emmetropia: this approach is my recommendation. If the child is older than 10-12 years of age, accurate power calculations are determined and that IOL is implanted. The average power of the anterior chamber lens is 19 diopters, whereas for posterior chamber lenses it is 20 diopters. If the postoperative refractive error is not plano, suitable spectacles with residual sphere, cylinder and bifbcals are prescribed. If an IOL power error is large and the eye has not developed severe and irreversible amblyopia, an IOL exchange may be considered. However, removing an IOL from the eye of a child is surgically difficult because of marked synechiae formation, which may lead to disruption of the anterior vitreous face with vitreous loss, the possibility of inducing chronic cystoid macular edema and cornea1 endothelial cell loss.
Complications Many operative and postoperative complications may be avoided by careful preoperative surgical planning. However, some postoperative complications may be predetermined because of the presence of additional pathological processes that coincidentally occur in eyes of children with developmental cataracts or following ocular trauma. The use of the operating microscope and microsurgical techniques is mandatory. Anterior segment reconstruction in traumatized eyes should also be performed in conjunction with IOL implantation. Vitreous loss was originally thought to be a major contraindication to IOL implantation. Vitreous loss is prevented by scleral support and the production of soft eyes with intravenous mannitol administered after the induction of general anesthesia. The Sheets lens glide is used during IOL implantation with an anterior chamber filled with Healon@ to depress the iris and protect the posterior capsule from rupture during implantation.“,‘” If‘ the posterior capsule ruptures and formed vitreous presents, a vitrectomy utilizing a mechanical cutting vitrector is performed. This technique produces a clear visual axis, a larger pupillary opening, and reduced postoperative inflammatory responses due to the removal of the stimulants to excessive inflammation and fibrosis. Vitreous loss occurs more frequently during secondary implantation and in patients who have had previous discissions of their posterior capsules. Blood in the anterior chamber at the conclusion of the operation may have serious late conse-
376
Surv Ophthalmol
34 (5) March-April
1990
quences. Since red blood cells are sources of anterior chamber fibrosis, collections of blood must be irrigated from the anterior chamber prior to wound closure. Iridocyclitis follows intraocular surgery in pediatric patients and is beneficial to assure adequate synechiae formation between the IOL loops and the ocular tissues. However, topical and systemic corticosteroids are used to control excess inflammatory reactions which are associated with: posterior synechiae; iris-IOL synechiae; IOL, cornea1 and vitreous precipitates; cyclitic and post-pseudophakos membranes; vitreous haze, and pupillary block glaucoma. Peripheral iris erosion or iris sphincter erosion occurs with iris supported lenses. Patients with posterior chamber lenses may develop iris capture, usually associated with marked posterior capsular opacification. Two patients in my series with anterior chamber lens implants have developed pupil elongation due to ectropion uveae. The prevention of cornea1 endothelial cell damage is of great importance, as the integrity of the cornea1 endothelium is an essential factor for the maintenance of cornea1 transparency. IOL implantation reduces the endothelial cell population by several mechanisms: direct endothelial trauma at the time of IOL implantation, additional surgical manipulations needed to place the IOL, the use of intraocular medications and irrigation solutions, the presence of the IOL within the eye, and late IOL touch. Ocular trauma seems to be the most important factor in reducing cornea1 endothelial cell counts. A prospective cell count of these patients has been suggested by Binkhorst et al4 to exclude from IOL surgery those patients with low preoperative endothelial cell densities, although specific cell density recommendations below which an IOL is not implanted remains unknown. Post-pseudophakos membranes follow extracapsular cataract extractions, and the incidence of these membranes is much higher following pediatric cataract surgery. They may arise anytime from six weeks to five years after IOL implantation. The membrane may be dense, or it may be filamentous and easily separated from the IOL with a discission knife to create a visual opening.” Wider anterior capsulotomies with greater removal of the capsular epithelium reduces the source of proliferation of fibrous tissue. The complications of cornea1 edema, bullous keratopathy, retinal detachment, or cystoid macular edema are extremely uncommon following primary or secondary lens implantation of flexible openlooped one-piece PMMA anterior or the Sinskey posterior chamber lenses. They have not yet oc-
BARER, HILES, MORGAN TABLE
1
Postoperative Complications Occurring in Aphakic Children Optically Rehabilitated With Contact Lens, Intraocular Lens and Epikeratophakia Grafts
Comnlication
Contact Lens
IOL
Epikeratophakia
#(%)
#(%)
#f%)
Cornea1 edema/clouding Cloudy graft Iris complications Glaucoma Endophthalmitis infection Detached retina Uveitis Phthisis bulbi Dislocated IOL Power errors > ? 3.00 D
NANA1g(6) o6(2) o4(l) NANA-
29( 10) NA43(15) 10(3) o8(3) l(1) 2(l) 24(8) 36(13)
18(17) NAl(1) 2(2) 3(3) ooNAlB(17)
TOTAL EYES
328
286
106
l(1)
l(l)
NA = Not Applicable
curred in my series, in which data are comparable to other IOL series.” IOLs should be removed if they are unstable, induce cornea1 endothelial cell loss, or cause cystoid macular edema. However, since many IOL patients are contact lens failures initially, further conservative optical therapy may not be successful and visual rehabilitation will remain minimal.6 The frequencies of postoperative complications listed in Table 1 are from data compiled from our practice series of eyes treated with contact lenses, IOLs, or epikeratophakia. Based upon the rigid selection criteria for IOL candidates commencing in 1974, and epikeratophakia graft procedures in 1984, eyes with marked pre-existing defects were directed toward the use of contact lenses. Cornea1 edema and stromal clouding occurred in contact lens patients as a result of the original disease processes, while the same complication in an IOL or epikeratophakia eye may have been due either to the original disease process and/or from the presence of the IOL leading to cornea1 endothelial decompensation, or from decompensation of the epikeratophakia graft. Iris complications occurred in IOL patients because of the propensity of iris suture lenses to produce iris sphincter or peripheral iris erosions. Eyes with posterior chamber lenses developed iris capture and synechiae to the IOL, which either covered the IOL with the iris or displaced the IOL. Glaucoma occurred in greater numbers in the contact lens patients. If glaucoma was suspected because of pre-existing defects, these eyes were not selected for IOL implantation or epikeratophakia grafting. Uveitis and endophthalmitis were rare
VISUAL REHABILITATION
OF APHAKIC
TABLE Secondary Surgeries Performed in Eyes Receiving Contact
377
CHILDREN 2
Contact Lens, Intraocular
Lens and Epikeratophakia
of Surgery
# Eyes
# ops
# Eyes
# ops
ELIA* Discission Nd: YAG laser Glaucoma Penetrating keratoplasty Enucleation Detached retina Others Dislocated IOL surgery IOL explant Graft removal Kegraft
28 129 2 19 0 4 1 8
2 129 7 5 1 3 3 4 16 16 NA NA
2 185 7 7 1
NA NA NA NA
42 147 2 51 0 4 1 10 NA NA NA NA
TOTAL EYES
328
257
286
Type
*Postoperative
examinations
under
anesthesia
# Ops
# Eyes
3 4 4 22 16 NA NA
13 12 0 0 0 0 0
14 14 0 0 0 0 0
NA NA 14 12
NA NA 13 12
251
112
.54
without other surgical interventions.
complications following cataract surgery and the use of any aphakic optical modality. Phthisis bulbi likewise occurred more commonly in contact lens patients and was due to pre-existing defects. Late detached retinas occurred at the same rate in each of the three series. Optical power errors remain a concern in young children. The earlier an optical device is utilized, the greater is the propensity for the development of power errors.
of operations these eyes received (Table 2). In many instances the technique of the original surgery predisposed to additional operations, e.g., cataract aspiration without a primary posterior capsulotomy, or the implantation of a posterior chamber IOL with subsequent reocclusion of the primary posterior capsulotomy by the regrowth of a secondary membrane. Thus our data include posterior capsulotomies either by discission or Nd : YAG laser techniques. In addition, the selection of eyes to receive intraocular lenses or epikeratophakia grafts was more critical than those receiving a contact lens, so the latter eyes had a greater propensity to complications requiring additional surgery. The result of this selection is particularly noteworthy for contact lens patients with glaucoma.
Secondary Surgeries Secondary surgeries may be required to maintain the integrity of the eye or optical rehabilitation following cataract surgery. We reviewed our series, and tabulated the number of eyes and the number
TABLE OccurrrrLsrs of Secondary Swgq
Grafts
Epikeratophia
IOL
Lens
3
Following Intraocular
Lens Implantation
by Style of Lens
Iris Suture
Anterior Chamber
Posterior Chamber
TOTAL
(N= 192) EYES (OPS)
(N =40) EYES (OPS)
(N = 53) EYES (OPS)
(N = 285) EYES (OPS)
Discissiori Detached retina Glaucoma Enucleation Examination under anesthesia Nd : YAG laser IOL relocation Explant Other Penetrating keratoplasty
104(152) 2(2) 2(4) 3(3) 2(2) I(I) 13(19) 14(14) 4(4) l(1)
2(2) l(1) l(1) oo-
l(1) 0O-
23(31) o2(2) Oo4(4) l(1) l(1) oo-
129(185) S(3) .‘(7) X(3) “(2) 7(7) 16(22) 16(16) 4(4) l(1)
# EYES (OPS) (WEY ES)
115(202) 60%,
Y(l0) 23%
27(39) 51%
151(250) 53%
Type
of Surger)
ii;;
378
Surv Ophthalmol
34 (5) March-April
1990
BARER, HILES, MORGAN TABLE 4
Best Corrected Visual Acuities and Aphakic Optical Correction Modalities of Consecutive Traumatic Cataracts in Children (1977-I 987)
Ootical Correction Visual Acuity
None #(%)
Glasses #(So) --
I( I;)
2Ol20-40 20/50-100 201200 < 20/200*
l&9:)
I(25) I(25) ~(50)
TOTAL
16
4
Modalitv
Contact Lenses #(So)
IOL #(%)
48(56) 16(19) S(9) 13(15)
67(61) ll(10) 6(5) 26(24)
85
Epikeratophakia #(%) 5(24) 6(32) I(6) 509)
110
17
TOTAL #(%) 120(52) 35(15) I6(7) 61(26) 232
*or unknown
Enucleations were performed on three eyes with IOLs; two had developed intractable secondary glaucoma and one had developed an inoperable retinal detachment and secondary glaucoma. Four contact lens eyes were enucleated because of the same complications. No epikeratophakia eyes have been enucleated. It should be noted that in intraocular lens eyes secondary surgeries were required more frequently in patients with iris suture lenses used between 1974 and 1981 than with anterior chamber or posterior chamber lenses used from 1981 through 1988 (Table 3).““*“S’i
Visual
Results
The visual acuities of the 286 IOL patients in my series (since 1974) were compared with those of other patients who had been operated in the same time period and had received contact lenses or epikeratophakia grafts. Only those children with traumatic or unilateral nontraumatic infantile cataracts are recorded for comparison purposes (Tables 4 SC 5). Overall, 95 (33%) IOL patients achieved corrected visual acuity of 20120 to 20140, and 63 (22%) patients attained 20150 to 20/100. Twenty-seven (10%) patients have 20/200 and 99 (35%) have less
TABLE
than 20/200 visual acuities. Of traumatic cataract patients, 61% achieved 20120 to 20140 acuity, whereas only 16% of the infantile cataract patients achieved this level of vision. The ages at IOL implantation in traumatic versus infantile cataract eyes were compared.g Patients with high levels of pretrauma visual development achieved superior postoperative results unless damage to other ocular structures by the initial trauma prohibited a good visual result. Younger traumatic cataract patients tended to develop amblyopia similar to that found in patients with unilateral infantile cataracts; vigorous treatment is essential to a successful visual result. Patients with infantile cataracts with an early age of onset frequently have very poor postoperative visual results because of obstruction of the visual axis during the crucial sensitive period. Early onset cataracts are also often associated with a higher incidence of other ocular and systemic abnormalities leading to dense deprivation amblyopia. When the visual results achieved by primary and secondary IOL implantation were compared, no significant differences were observed following the two implantation methods in traumatic cataract patients. However, infantile cataract patients with pri-
5
Best Corrected Visual Amities and Aphakic Optical Correction Modalities of Consecutive Unilateral Cataracts (Birth Through 17 Years, 1977-l 987)
Optical Correction
Visual Acuity
Classes #(%)
Contact Lenses #(%)
2Ol20-40 20/50-l 00 201200 < 20/200
---l(100)
10(11) 8(9) 14( 16) 58(64)
TOTAL
1
90
IOL #(%) 28( 16) 52(30) 21(12) 73(42) 174
Modality Epikeratophakia ‘#(%)
TOTAL #(%)
l(3) 2(6) 6(17) 27(75)
39(13) 62(2 1) 41(14) 159(52)
36
301
VISUAL REHABILITATION
OF APHAKIC
mary implants showed a better visual result in the 20/2O to 20/40 category compared to those with secondary implants. Delays following contact lens failure and secondary IOL implantation seemed to enhance amblyopia.”
Conclusion Ophthalmologists managing children with cataracts must consider all of the ramifications of pediatric cataract surgery and their optical rehabilitative problems. The implantation of an intraocular lens (IOL) into the eye of a child is as safe and successful as other methods of aphakic rehabilitation when all of the proper precautions of case selection and surgical technique are utilized. IOLs offer a secondary mode of optical correction fol those contact lens patients who fail to wear their lenses. IOL implantation should be in the armamentarium of all surgeons who treat children with cataracts.
References 1. BinkhorstCD: The iridocapsular clip (four-loop) thalmol
(two-loop) lens and the iris lens in pseudophakia. Tram Am Acad Oph-
Otolaryngol
Binkhorst CD: suiar supported
77t589,
1973
Lens injury in children
treated with iridocapintraocular lenses, in Hiles DA (Ed): Intmor-= ulnr Lent Imphznls in ChddrPn. New York, Grune and Swatton, 1980, pp 8-146 S. Binkhorst CD, Gobin MH: Injuries to the eye with lens opacity in young children. Ophthalmologica 148:169, 1964 4. Binkhorst CD, Nygaard P, Loones LH: Specular microscopy of the cornea1endothelium and lens implant surgery. Am J 2.
Ophthalmol85:597,
4a.Burke
JP, Willshaw
1978
HE, Young
JDH:
Intraocular
379
CHILDREN
lens im-
IV. Epikeratophakia. KEN-H S. MOKCAN. I M.D., d-leans, Lkisiana Optically, contact lenses are the ideal method of correcting aphakia in children; however, problems with compliance may interfere with rehabilitation. The best fit contact lens is effective only when it is in the eye, and active children can easily dislodge and lose lenses, which is both frustrating and expensive for the parents. Moreover, some young patients have associated conditions that preclude good contact lens correction. A contact lens must move slightly on the cornea for a proper fit. This means that during ocular saccades or in eyes with nystagmus, the optical center of the lens is rarely aligned with the visual axis of the eye. Before epikeratophakia became available, the options for a child with unilateral aphakia who would not or could not wear a contact lens were either aphakic spectacles or secondary implantation of an
plants
for uniocular
73~860-864,
5. Chovce ante&r 78t459,
cataracts
in childhood.
Hr./ Ophthalmol
1989
P: Correction of uniocular aphakia by means of chamber acrylic implants. 7‘mns Ophthnlmol Sot l[K 1958
techniques and complications associ6. Wiles DA: Indications. ated with intraocular lens implantation in children, in Hiles DA (Ed): In@aoculnr Lens Implants m Childrpu. New York. Crune and Stratton, 1980, pp 189-268 Hiles DA: Intraocular lens in children. .4m 1~lrr~~r~lnr /TNfhznt SotJ 8: 17 1, 1982 Hiles DA: Part 111: Infantile cataracts-aphakic optical correction. Int J Cataract Surg 1:20-29, 1984 Wiles DA: Intraocular lens implantation in children with monocular cataracts. 1974-19XJ. V@th&noic)~q 91: 125 I, 1984 10 Hiles DA, Wallar PH, Biglan AW: Surgery of traumatIc cataracts. Inl Ophthalmol Clin I7:147, 1977 II Hiles DA, Hered RW: Modern intraocular lens implants in children with new age limitations. ,/ (:olnmc/ Ku/ir~rl Surg l3:493-497, 1987 12. Hoffer KJ: Selection of lens power for implantation in infants and children. Am Intmorular Implant Sot J lt49, 1975 13. Maltrman BA, Wagner RS, Capuro AR: Neodymium: YAG laser surgery: Th&trearment &f pediatric car&act disease. .4nn Ophthalmol 18.245, 1986 14. Parks MD, Hiles DA: Management ofinfantile cataracts. ,4m / Ophthalmol fj3:10, 1967 1.5. Scheie HG: Aspiration of congenital or soft cataracts: A new techniaue. Am I Obhthalmol 50:1048. 1960 16. Sheets jH: Lens ilide in implant surgery. Arch (Iphthnlmol 96:145, 1978 17. Sinskey KM, Pate1 J: Posterior chamber intraocular lens implants in children: Report of a series. .4m Intrclonclnr Imfi[ant Sor J 9:157, 1983 17a..lByl~~r D: Editorial: Monocular infantile cataract, intraocular lenses, and amblyopia. BrJ Ophthnlmol7?:857-858, 1989 18. Van Balen AT: Four years’ experience with Binkhorst lens implantation. Am J Ophthalmol 75:755, 1973 Reprint address: David A. Hiles, M.D., Ophthalmology, 3.518 Fifth Ave., Pittsburgh,
Louisiana
Oakland Pediatric PA 152 13.
State University Eye Center, New
intraocular lens. Although there are anecdotal reports of an occasional good result with spectacles, the optical distortion makes this outcome highly unlikely in children who are unilaterally aphakic. Secondary intraocular lens implantation may provide rapid visual rehabilitation, but this procedure has been associated with postoperative complications, including cystoid macular edema, intraocular hemorrhage, postoperative astigmatism, ischemic optic neuropathy, persistent uveitis, uveitis-glaucoma-hyphema (UGH) syndrome, infectious endophthalmitis, retinal detachment, and cornea1 decompensation.’ Secondary intraocular lens implantation in children has been associated with a high rate of secondary surgeries, including membrane removals, lens relocations, and lens removals.“’
OF APHAKIC
23. Helveston EM, Saunders RA, Ellis FD: Unilateral cataracts in children. Ophlhalmic Szcrg 1 I: 102-108, 1980 24. Hiles DA, Walter PH: Visual results following infantile cataract surgery. Int Ophthdmol Clin 17:265-282, 1977 25. Hiles DA: Visual acuities of monocular IOL and non-IOL aphakic children. Ophthalmology 87:1296-1300, 1980 lens implantation in children with 26. Hiles DA: Intraocular monocular cataracts 1974-1983. Ophthalmology: 91: 1231. 1984 of pediatric aphakia. .4rrh 27. Hoyt CS: The optical correction Ophlhnlmol 104:6.i l-652, 1986 28. Hoyt CS, Nickle B: Aphakic cystoid macular edema. Occurrence in infants and children after transpupillary lensectomy and anterior vitrectomy..4rch Ophlhalmol100:746-749. 1982 29. Hubel DH, Wiesel TN: The period of susceptibility to the physiologic effects of unilateral eye closure in kittens.,] Phy\io/ 206:419, 1970 30. Jacobson SC, Mohindra 1, Held R: Development of visual acuity in infants with congenital cataracts. BrJ Ophlhalmol 65:1727-1735, 1981 3 1 Karr DJ, Scott WE: Visual acuity results following treatment of persistent hyperplastic primary vitreous. Arch Ophthalmol lOJ:662-667, 1986 32. Kelly Cc;, Keates RH, Lembach KG: Epikeratophakia for pediatric- aphakia. Arch Ofihthalmol 104-680, 1986 33. Kenyon K, Poise KA, Seger RG: Influence of wearing schedulc on extended-wear complications. Ophthalmology 93: 23 l-236, 1986 34. Kersley HJ, Kerr C, Pierce D: Hydrophilic lenses for “continuous-wear” in aphakia: Definitive fitting and the problems that occur. Rr J Ophthal 61:38&42, 1977 35. Kushnel- BJ: Visual results after surgery for monocular juvenile cataracts of undetermined onset. Am J Ophthalmol fO2:468-472, 1986 36. Leibowitz HM, Laing RA, Sandstrom MC: Continuous wear of hydrophilic contact lenses. ,4rch Ophthalmol 89~306-3 10, 1979 37. Leinfelder PJ: Amblyopia associated with congenital cataract. Am J Ophthalmol 55t527, 1963 3x. Maumenee AE: Symposium on congenital cataracts. Oph1hmlmoloRy 86: 1605, 1979 39. Moore d: The fitting of contact lenses in aphakic infants. ,/ ,-lm Optomrtnc A.\sn 56: 180-l 83, 1985 40. Morgan KS, Marvelli ‘Il., Ellis GS. Arffa RC: Epikeratophakia in children with traumatic cataracts.] Pedialr Ophthnlmol Slrahism~cs 23: 108, 1986 41. Morgan KS. Arffa KC, Marvelli TL, Verity SM: Five year followup of epikeratophakia in children. Ophthalmology 93.423, 1986 42. Morgan KS, Stephenson GS, McDonald MB, Kaufman HE: Epikeratophakia in children. Ophthalmology 91~780-78.1,
I984 43.
44.
371
CHILDREN
Morgan KS, Franklin KM: Oral fluorescein angioscopy in aphakic children. ,I Prdintr Ophthnlmol Strabismus 21.~33-36. I984 Nelson LB, Cutler SF, Calhoun JH, et al: Silsoft extended wear contact lenses in pediatrjc aphakia. Ophthalmology Y9:1.5”!?-1.531 _ . 1985.
45. 46. 47. 48.
49. 50. 51.
52.
53.
54.
55. 56. 57
58 59.
60.
61.
62. 63. 64. 65. 66.
Nelson LB: Diagnosis and management ofcataracts in infancy and childhood. Ophthalmic Surg 15:688-697, 1984 Parks MM, Hiles DA: Management of infantile cataracts. Am J Ophthalmol 63: IO, 1967 Parks MM: Visual results in aphakic children. ,~TNJ Ophlhalmol 94;441-449, 1982 Pierse D, Kersley HJ: Hydrophilic lenses for “continuouswear” in aphakia: Fitting at operation. H? ,/ Ophthnlmol 61:34-37. 1977 Poer DV, Helveston EM, Ellis FD: Aphakic cystoid macular edema in children. Arch Ophthalmol 99:249-252, 1981 Powers MK, Dobson V: Effect of focus on visual acuity of human infants. Vision Ke.\ 22:52 1, 1982 Pratt-Johnson JA, Tillson C: Visual results after removal of congenital cataracts before the age of 1 year. (:a?~,/ Ophthnla01 l&19-21, 1981 Pratt-Johnson JA, Tillson G: Hard contact lenses in the management of congenital cataracts../ P&alr Oph~hnlmd Slmhumu.s 2294-96, 1985 Robb KM, Mayer DL. Moore BD: Results of early treatment of unilateral congenital cataracts. 1 P&III. Ophlhahol 24:17X-181. 1987 Rogers CL, Tishler CL, Tsou BH, et al: Visual acuities in infants with congenital cataracts operated on prior to 6 months of age. Arrh Ophthalmol 99t999-1003. 19X1 Rogers CL: Extended wear silicone contact lenses in children with cataracts. Ophthalmo/og? 87:X67-870, 1980 Ryan SJ, Maumenee AE: Unilateral congenital cataracts and their management. Ophlhalmir Surg Y:35, 1977 Saunders RA, Ellis FD: Empirical fitting of hard contact lenses in infants and young child&. Ophthnlmolog? HX:lP7-130, 19x1 Schic HG: Aspiration of congenital or soft cataracts. A new technique. Am J Ophthalmol 50: 1048, 1960 Shaw EL, Gasset AR: Experience in the use of soft contact lenses for the correction of monocular and binocular aphakia. :lnn Ophthnlmol 5:937-943, 1973 Taylor D: Choice of surgical technique in management of congenital cataracts. Tmn\ Oph~hrdmol Sot C’K lOI: 14-l 17, 1981 .l‘aylor D, Vaegan, Morris JA, et al: Amblyopia m bilateral infantile and juvenile cataract. Relationship to timing of treatment. Trans Ophthalmol Sot UK 99:170-l 75. 1979 Vaegan TD: Critical period for deprivation amblyopia in children. Tmns Ophthalmol Sot L’K 99:432-439, 1979 Van Noorden GK: Stimulus deprivation amblyopia. Am ,/ Oph/hnlmol 924 16-42 1, 198 I Weissman B: Fitting aphakic children with rontart lenses.,/ .Am Oplom Asoc 51:235-237, 1983 Wiesel TN, Dubel DH: Extent of recovery from the effect of visual deprivation in kittens. J Nmirophysiol 2X: 1060, 1965 CViesel TN: Effects of monocular depl:ivation on the cat’s visual cortex. Tram ,4m Acarl Ophthalmol Otolqngol 75: 1 186. 1971
Reprint address: John D. Baker, M.D., Department thalmology, Children’s Hospital of Michigan, 3901 Blvd., Detroit, MI 48201.
III. Intraocular Lenses. DAVID A. HILES, M.D.,De artment of Ophthalmology, Pittsburgh School of Medicine, Pittsburgh, Penny Pvania While discussing options of aphakic optical devices prior to surgery, all rehabilitative modalities must be considered by the ophthalmologist and the child’s family. Glasses are useful for children with bilateral aphakia. While expensive, and applied as only part-time optics, they are noncontact and easily modified devices. They are not worn successfull)
of OphBeaubien
University of
by unilateral aphakes because of the associated anisometropia and anisokonia. No child in my experience, either with an infantile or acquired unilateral cataract, has been visually rehabilitated with unilatera1 aphakic spectacles. Contact lenses remain the preferred aphakic correction modality for most infants and children. Ker-
372
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34 (5) March-April
BAKER, HILES,
1990
atometry and refraction are performed upon small children under the same general anesthesia as the cataract aspiration. The lenses are fitted upon the eye within the first few postoperative days or when the intraocular surgical inflammatory response has subsided. Lens modifications are made over the first three years of life to compensate for the rapid myopic shift of the infant apbakic eye.4a It became apparent early in my experience that the expense of contact lenses to many patients was great, the insertion and removal of the lens was often traumatic, the loss rate was often high, and wear and compliance decreased with time and with changes in the socioeconomic conditions within the family. I still recommend, however, that infants born with unilateral or bilateral cataracts be operated on within the first week(s) of life and be fitted with a contact lens followed by occlusion of the sound eye when appropriate. The implantation of a unilateral intraocular lens (IOL) in a child’s eye was first performed by Choyce’ in 1956 followed by Binkhorst in 1959.3 Controversy soon arose over IOL rehabilitation for children. Cataract surgery performed on pediatric patients differs from that performed on the adult.’ Pediatric ophthalmologists have been reluctant to implant lenses because of their fear of the longterm effects of an IOL in a child’s eye, and because of their hesitation to depart from the highly successful small incision cataract aspiration technique first advocated by Scheie in 1960.15 Ophthalmologists performing adult cataract extractions implant IOLs as a routine procedure and do not fear the larger incisions and complications associated with IOL insertion. However, these surgeons frequently overlook the complications of pediatric intraocular surgery and neglect the necessary optical, amblyopia and strabismus corrections necessary for children.*
Iedications for IOL Implantation There are two major indications for IOL implantation in children. The first, and most important, is to preserve vision and prevent amblyopia. The second is the preservation or development of fusion.6,‘7a Patients should be considered for IOL implantation if the parent or the child refuses contact lens wear, if the ophthalmologist deems that contact lens wear would not be successful due to patient or parent noncompliance, or if other social or economic factors preclude adequate contact lens follow-up.* IOL implantation should be confined to unilateral aphakic children because of the unknown very longterm effects of the presence of an IOL and its component materials in the human eye. In patients with bilateral cataracts and asymmetrical visual loss, IOL implantation into one eye is usually performed
MORGAN
after contact lens failure in order to improve that eye’s acuity. The visual results for these eyes are the same as for unilateral cataract eyes. If acuity fails in the fellow eye due to increasing density of that cataract, IOL implantation is not warranted and another contact lens should be tried or an epikeratophakia graft should be considered. INFANTILE
CATARACTS
Infantile cataracts are those occurring in children with a lens opacity present at birth or arising before the eighth birthday. Included here are familial or sporadic mutations, metabolic and syndrome-related cataracts, anterior PHPV, posterior lenticonus, and progressive late onset juvenile cataracts.6 Unilateral infantile cataract patients older than two to three years are IOL candidates. Children less than eight years of age in the amblyopia-forming age group require the additional therapeutic modality of amblyopia occlusion. Spectacles to correct residual optical errors, if necessary, are well tolerated and accepted by most children.’ IOLs have not been implanted in neonates because of prolific production of secondary membranes and synechiae formation. It may be these young eyes that will most benefit from IOL implantation techniques in the future, for very early IOL implantation may yet prove as surgically successful as has the neonatal removal of infantile cataracts. With neonatal IOL implantation the rapid myopic shift which occurs during the first years of life must be taken into consideration. TRAUMATIC
CATARACTS
Children with traumatic cataracts and cornea1 scars that preclude successful contact lens wear are also IOL candidates. Traumatic aphakic patients may be subdivided into those in the amblyopiaforming group up to eight years of age, and those beyond this age. Amblyopia occurs with traumatic cataracts and following surgery in young children. This is related to the age of the patient at the time of occlusion of the visual axis by the cataract and to the time elapsed before the eye is optically rehabilitated. The longer these intervals, the greater is the possibility of irreversible deprivation amblyopia. ‘“,‘4~‘8These patients may receive an IOL either as a primary procedure at the same surgery as repair of the globe and cataract extraction,‘0~‘4~‘s or secondarily following contact lens failure.6*‘0*‘4”8 More commonly, and more prudently, the IOL is implanted later, either with cataract surgery, or secondarily, after contact lens failure. Surgery should be deferred until the intraocular pressure and inflammation have returned to normal following trauma. Late cataract extraction and IOL implantation is performed when the lens has become
VISUAL REHABILITATION
OF APHAKIC
373
CHILDREN
opaque, visual fixation responses are decreased, or the corrected vision is 20/70 or less. A lens implant is a very satisfactory mode of aphakic correction in children over six years of age with traumatic cataracts. The IOL optics are crisp, clear and accurate, and vision rapidly returns with subsidence of the surgical trauma. If the eye is not severely damaged by cornea1 scars, glaucoma or posterior polar defects, visual restoration is excellent. Amblyopia therapy in amblyopia-prone patients and spectacle correction for all patients aids in the restoration of visual function. If strabismus develops, early surgery is indicated to restore a normal ocular alignment and secure the best possible peripheral, if not. central, fusion.
Contraindications to IOL Implantation Patients with microphthalmic eyes with corneas less than 10 millimeters in diameter should not receive IOLs because of insufficient space within the anterior chamber to assure that cornea1 endothelial touch will not occur during or following implantation. Patients with large central axial cornea1 scars continue to achieve poor postoperative visual results. Cornea1 grafting, while anatomically feasible, is not often visually successful in many young children. Eyes with congenital, familial or acquired aniridia following trauma have insufficient support systems for either an anterior chamber or iris-supported IOL. If the capsular bag and zonules are intact at the conclusion of cataract surgery, secure capsular fixation alone may be possible with a posterior chamber lens. Eyes with traumatic or syndrome-related dislocatkd lenses are not suitable for implantation because of their high incidence of retinal detachment and/or secondary glaucoma. Eyes with decreased endothelial cell counts following trauma or previous surgery should also be excluded. Eyes with infantile glaucoma also have been rejected, for they redevelop glaucoma, which is extremely difficult to control medically or surgically. 101,s should not be implanted into eyes with chronic intraocular inflammation, including the rubella syndrome, juvenile rheumatoid arthritis syndromes, toxocara canis, toxoplasmosis, pars planitis, or other chronic anterior or peripheral retinal inflammations. Late exacerbations of these inflammations may occur, which can be accompanied by synechiae formation and secondary glaucoma. Eyes with known retinal detachments, macular lesions, optic nerve defects or atrophy, or diabetes with progressive proliferative retinopathy are also not IOL canclidates.:
IOL Selection The selection of the IOL depends upon the need for fixation and the condition of the anterior seg-
ment related to immediate or previous ocular surgery or trauma and the age of the child at implantation. IRIS-FIXATED
IOLs
1 first selected the Binkhorst two-loop IOL based on the concept that firm iridocapsular adhesions formed by children would maintain secure and permanent IOL fixation. However, IOL dislocations did occur. Iris-suture lenses offered the additional advantage of a lens fixed in the pupillary space by iridocapsular adhesions, plus additional fixation supplied by the 10-O nylon iris suture. The small, lightweight lens does not encroach upon the anterior chamber angle or permit the haptic to become enmeshed within the capsular sac. The pupil may be dilated widely for retinal examination. The lens permits the eye to grow without affecting haptic placement, since neither the peripheral capsular bag, zonules, or angle are utilized for fixation, an important consideration in eyes of rapidly growing children.“,x However, corneat endothelial cell loss and cystoid macular edema have been observed from pseudophakodenesis, and the use of this type of lens has markedly decreased in recent years. Metal looped lenses and fixation devices were tried because the inert metal would not biodegrade with the passage of time. The heavy metal loops and clips led to iris sphincter erosion, pseudophakodenesis, continued cornea1 endotheliat cell toss leading to cornea1 edema, and an increase of cystoid macular edema. 1 no longer can recommend iris-fixation IOLS. ANTERIOR
CHAMBER
IOLs
As the lensectomy-vitrectomy cataract operation gained popularity among pediatric ophthatmologists, the secondary anterior chamber IOL offered the only possibility for IOL aphakic rehabilitation for these eyes. An IOL placed in front of the pupil should have minimal contact with the iris, avoid pupillary block, and permit adequate pupiltary dilation for examination of the retina and for secondary membrane surgery if required.’ Anterior chamber IOLs are indicated for children lacking posterior capsular support sufficient for a posterior chamber lens. This situation occurs in patients who have large posterior capsulectomies following lensectomy-anterior vitrectomy, or for those who have immobile, dilated pupils following trauma. Since the child’s eye is almost fully grown between three and six years of age, a lens with the potential for elongating slightly as the anterior segment of the eye completes its growth is ideal for this application. The need for secondary membrane surgery in these eyes is uncommon. If a membrane does occur, a surgical discission under the lens or
374
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34 (5) March-April
1990
Nd : YAG laser capsulotomy is easily performed. I now recommend a flexible one-piece open looped PMMA primary anterior chamber intraocular lens for all contact lens-noncompliant children between three and six years ofage as either a primary or secondary IOL implantation, as well as for children over six years of age who receive secondary lens implantation. Several specific surgical recommendations are suggested for anterior chamber lens implantation. The lens should not be placed into an eye with vitreous protruding into the anterior chamber. A vitrector should be used to clear the visual axis of vitreous and other lens remnants prior to implantation. Healon@ is placed in the anterior chamber to protect the anterior iris surface from trauma and to reduce cornea1 endothelial cell loss during implantation. A Sheets lens glide is used to further protect the iris when the lens passes over its surface. After the lens is in place, the wound is closed with interrupted 9-O polygalactin sutures, and 4-mirror gonioscopy is performed to assure that the lens pods are in proper position in the anterior chamber angle. POSTERIOR
CHAMBER
IOLs
I prefer the posterior chamber lens for implantation in all children with otherwise normal anterior segments undergoing primary intraocular lens implantation. Based upon new data gathered from my series, I have established new guidelines for intraocular lens implantation in children.4”8 ” I now recommend that posterior chamber intraocular lenses be implanted in eyes of children six years of age and older, or in those younger children who are able to undergo Nd : YAG laser capsulotomies. Posterior chamber lenses are particularly useful for older children who have had normal eyes prior to the onset of the cataract. Postoperative rehabilitation is rapidly achieved with the restoration of normal vision using a high quality optical device. I prefer the Sinskey soft J loop lens design with lo-degree forward anterior angulation of the haptics. A posterior chamber lens is selected for primary implantation when the anterior segment of the eye is normal except for the cataract, and when the posterior capsule remains intact or has only a small central posterior capsulotomy without vitreous presentation following cataract aspiration. A secondary posterior chamber lens is implanted if the posterior capsule is intact, or if vitreous is not protruding through a previously created central capsulotomy, and if the peripheral posterior capsular membrane would support and adhere to the lens haptics. The exact position of the lens haptics cannot always be
BAKER, HILES, MORGAN determined because the space between the posterior capsule and the iris may be compressed due to the collapse of the child’s sclera producing forward vitreous pressure. At the conclusion of the procedure, all eyes with a posterior chamber lens receive a central posterior capsulotomy after the lens is in position and the eye has been closed. Posterior chamber lens candidates require meticulous attention to specific aspects of the cataract aspiration as well as the lens implantation. Healon@, rather than continuous irrigation, is used to reform the anterior chamber during the anterior capsulectomy. The phacoemulsifier is recommended to reduce the operative time of cataract aspiration to a minimum, thus decreasing trauma to the iris and preventing rupture of the posterior capsule. Anterior chamber irrigation is reduced during phacoemulsification to prevent iris prolapse and pigment epithelial loss. Such iris trauma in children induces synechiae formation between the iris and lens haptic or optic, leading to iris capture and IOL malposition. Anterior chamber Healon* and a Sheets lens glide facilitate implantation of the lens. Accurate loop placement is often impossible because of the collapsible nature of the child’s eye. In-the-bag loop placement frequently occurs with the inferior loop, but the superior loop is usually placed in the ciliary sulcus. Manipulation of the superior iris to implement loop placement is avoided, for this induces synechiae formation and iris capture. Additional trauma may occur to the iris pigment epithelium during rotation of the posterior chamber lens to a horizontal position. Primary posterior capsulotomies are routinely performed under the posterior chamber lenses at the conclusion of the procedure. It should be stressed, however, that even with a primary posterior capsulotomy, in 63% of our patients, the visual axis became re-occluded by secondary membranes, and required secondary capsulotomies. ” Secondary surgery required to create a posterior capsulotomy in these eyes is complicated by the position of the lens behind the iris. Even with the use of viscoelastic agents, there is a high risk of dislodging the lens during the discission operation by breaking the synechiae that secure it in place. If this occurs, vitreous may prolapse around the lens and into the anterior chamber, causing further lens malposition. Cornea1 endothelial cell loss may occur by lens optic touch if the anterior chamber should accidently collapse during the operation. Iris trauma may lead to further synechiae between it and the lens, inducing additional iris capture, lens tilt, or visual axis occlusion. Nd: YAG laser posterior capsulotomies may be accomplished in children over six years of age. This
VISUAL REHABILITATION
technique induces less trauma to the eye than an operative disc&ion, does not require general anesthesia, and may be repeated if additional capsular opacification occurs.‘” Patients younger than six years of age are generally poor candidates for Nd :YAG laser capsulotomy, as they are often frightened and become uncooperative. The operative risk for laser therapy is higher for them because the capsulotomy must be performed under general endotrachial anesthesia with the child placed in an upright position at the laser, which is often located outside of the operating room environment. Posterior chamber lens implantation is contraindicated as a secondary procedure unless an intact posterior capsule or adequate peripheral capsule is present to support the lens. In addition, sufficient iris and capsular synechiae formation to the haptics is required to prevent lens malposition; these synechiae frequently do not form and dislocation of the IOL occurs.” Iris synechiae to the posterior capsule, irregular fixed pupils, and collapse of the capsular bag with adhesions of the anterior and posterior capsule make identification of capsular clefts difficult, thus precluding secondary posterior chamber lens implantation into the eyes of most young children. Even though a primary posterior capsulotomy is always performed at the conclusion of the implantation procedure, anterior capsular epithelial cell metaplasia and proliferation often lead to thick, tough, dense, secondary membranes which re-ocelude the original posterior capsulotomy and induce haptic dislocation and superior iris capture. Apparently these cells utilize the intact formed anterior vitreous face of children, as well as the posterior surface of the IOL, as a scaffolding for cellular proliferation and migration which re-oceludes the clear visual axis created in the previously opened posterior capsule. This synechiae formation and lens capsular opacification precludes adequate pupillary dilatation for retinal examinations, and for visual development.
Intraocular
375
OF APHAKIC CHILDREN
Lens Power
The IOL powers are either emperically determined or are calculated from keratometric readings, A-scan axial lengths, anterior chamber depths and refractive errors. Hoffer” has described the dilemma of IOL power determination in children. An 101, may be selected to produce emmetropia at the time of implantation, but with growth ofthe eye, optical errors of increasing magnitude may occur. A second consideration is to replace the IOL in adulthood with an IOL of lesser power. This approach is particularly hazardous, for it requires a difficult secondary operative procedure to remove the IOL.
which is firmly fixed to the intraocular structures. The third suggestion is to implant an IOL of a power suitable for an adult, thus allowing the child to grow toward emmetropia: this approach is my recommendation. If the child is older than 10-12 years of age, accurate power calculations are determined and that IOL is implanted. The average power of the anterior chamber lens is 19 diopters, whereas for posterior chamber lenses it is 20 diopters. If the postoperative refractive error is not plano, suitable spectacles with residual sphere, cylinder and bifbcals are prescribed. If an IOL power error is large and the eye has not developed severe and irreversible amblyopia, an IOL exchange may be considered. However, removing an IOL from the eye of a child is surgically difficult because of marked synechiae formation, which may lead to disruption of the anterior vitreous face with vitreous loss, the possibility of inducing chronic cystoid macular edema and cornea1 endothelial cell loss.
Complications Many operative and postoperative complications may be avoided by careful preoperative surgical planning. However, some postoperative complications may be predetermined because of the presence of additional pathological processes that coincidentally occur in eyes of children with developmental cataracts or following ocular trauma. The use of the operating microscope and microsurgical techniques is mandatory. Anterior segment reconstruction in traumatized eyes should also be performed in conjunction with IOL implantation. Vitreous loss was originally thought to be a major contraindication to IOL implantation. Vitreous loss is prevented by scleral support and the production of soft eyes with intravenous mannitol administered after the induction of general anesthesia. The Sheets lens glide is used during IOL implantation with an anterior chamber filled with Healon@ to depress the iris and protect the posterior capsule from rupture during implantation.“,‘” If‘ the posterior capsule ruptures and formed vitreous presents, a vitrectomy utilizing a mechanical cutting vitrector is performed. This technique produces a clear visual axis, a larger pupillary opening, and reduced postoperative inflammatory responses due to the removal of the stimulants to excessive inflammation and fibrosis. Vitreous loss occurs more frequently during secondary implantation and in patients who have had previous discissions of their posterior capsules. Blood in the anterior chamber at the conclusion of the operation may have serious late conse-
376
Surv Ophthalmol
34 (5) March-April
1990
quences. Since red blood cells are sources of anterior chamber fibrosis, collections of blood must be irrigated from the anterior chamber prior to wound closure. Iridocyclitis follows intraocular surgery in pediatric patients and is beneficial to assure adequate synechiae formation between the IOL loops and the ocular tissues. However, topical and systemic corticosteroids are used to control excess inflammatory reactions which are associated with: posterior synechiae; iris-IOL synechiae; IOL, cornea1 and vitreous precipitates; cyclitic and post-pseudophakos membranes; vitreous haze, and pupillary block glaucoma. Peripheral iris erosion or iris sphincter erosion occurs with iris supported lenses. Patients with posterior chamber lenses may develop iris capture, usually associated with marked posterior capsular opacification. Two patients in my series with anterior chamber lens implants have developed pupil elongation due to ectropion uveae. The prevention of cornea1 endothelial cell damage is of great importance, as the integrity of the cornea1 endothelium is an essential factor for the maintenance of cornea1 transparency. IOL implantation reduces the endothelial cell population by several mechanisms: direct endothelial trauma at the time of IOL implantation, additional surgical manipulations needed to place the IOL, the use of intraocular medications and irrigation solutions, the presence of the IOL within the eye, and late IOL touch. Ocular trauma seems to be the most important factor in reducing cornea1 endothelial cell counts. A prospective cell count of these patients has been suggested by Binkhorst et al4 to exclude from IOL surgery those patients with low preoperative endothelial cell densities, although specific cell density recommendations below which an IOL is not implanted remains unknown. Post-pseudophakos membranes follow extracapsular cataract extractions, and the incidence of these membranes is much higher following pediatric cataract surgery. They may arise anytime from six weeks to five years after IOL implantation. The membrane may be dense, or it may be filamentous and easily separated from the IOL with a discission knife to create a visual opening.” Wider anterior capsulotomies with greater removal of the capsular epithelium reduces the source of proliferation of fibrous tissue. The complications of cornea1 edema, bullous keratopathy, retinal detachment, or cystoid macular edema are extremely uncommon following primary or secondary lens implantation of flexible openlooped one-piece PMMA anterior or the Sinskey posterior chamber lenses. They have not yet oc-
BARER, HILES, MORGAN TABLE
1
Postoperative Complications Occurring in Aphakic Children Optically Rehabilitated With Contact Lens, Intraocular Lens and Epikeratophakia Grafts
Comnlication
Contact Lens
IOL
Epikeratophakia
#(%)
#(%)
#f%)
Cornea1 edema/clouding Cloudy graft Iris complications Glaucoma Endophthalmitis infection Detached retina Uveitis Phthisis bulbi Dislocated IOL Power errors > ? 3.00 D
NANA1g(6) o6(2) o4(l) NANA-
29( 10) NA43(15) 10(3) o8(3) l(1) 2(l) 24(8) 36(13)
18(17) NAl(1) 2(2) 3(3) ooNAlB(17)
TOTAL EYES
328
286
106
l(1)
l(l)
NA = Not Applicable
curred in my series, in which data are comparable to other IOL series.” IOLs should be removed if they are unstable, induce cornea1 endothelial cell loss, or cause cystoid macular edema. However, since many IOL patients are contact lens failures initially, further conservative optical therapy may not be successful and visual rehabilitation will remain minimal.6 The frequencies of postoperative complications listed in Table 1 are from data compiled from our practice series of eyes treated with contact lenses, IOLs, or epikeratophakia. Based upon the rigid selection criteria for IOL candidates commencing in 1974, and epikeratophakia graft procedures in 1984, eyes with marked pre-existing defects were directed toward the use of contact lenses. Cornea1 edema and stromal clouding occurred in contact lens patients as a result of the original disease processes, while the same complication in an IOL or epikeratophakia eye may have been due either to the original disease process and/or from the presence of the IOL leading to cornea1 endothelial decompensation, or from decompensation of the epikeratophakia graft. Iris complications occurred in IOL patients because of the propensity of iris suture lenses to produce iris sphincter or peripheral iris erosions. Eyes with posterior chamber lenses developed iris capture and synechiae to the IOL, which either covered the IOL with the iris or displaced the IOL. Glaucoma occurred in greater numbers in the contact lens patients. If glaucoma was suspected because of pre-existing defects, these eyes were not selected for IOL implantation or epikeratophakia grafting. Uveitis and endophthalmitis were rare
VISUAL REHABILITATION
OF APHAKIC
TABLE Secondary Surgeries Performed in Eyes Receiving Contact
377
CHILDREN 2
Contact Lens, Intraocular
Lens and Epikeratophakia
of Surgery
# Eyes
# ops
# Eyes
# ops
ELIA* Discission Nd: YAG laser Glaucoma Penetrating keratoplasty Enucleation Detached retina Others Dislocated IOL surgery IOL explant Graft removal Kegraft
28 129 2 19 0 4 1 8
2 129 7 5 1 3 3 4 16 16 NA NA
2 185 7 7 1
NA NA NA NA
42 147 2 51 0 4 1 10 NA NA NA NA
TOTAL EYES
328
257
286
Type
*Postoperative
examinations
under
anesthesia
# Ops
# Eyes
3 4 4 22 16 NA NA
13 12 0 0 0 0 0
14 14 0 0 0 0 0
NA NA 14 12
NA NA 13 12
251
112
.54
without other surgical interventions.
complications following cataract surgery and the use of any aphakic optical modality. Phthisis bulbi likewise occurred more commonly in contact lens patients and was due to pre-existing defects. Late detached retinas occurred at the same rate in each of the three series. Optical power errors remain a concern in young children. The earlier an optical device is utilized, the greater is the propensity for the development of power errors.
of operations these eyes received (Table 2). In many instances the technique of the original surgery predisposed to additional operations, e.g., cataract aspiration without a primary posterior capsulotomy, or the implantation of a posterior chamber IOL with subsequent reocclusion of the primary posterior capsulotomy by the regrowth of a secondary membrane. Thus our data include posterior capsulotomies either by discission or Nd : YAG laser techniques. In addition, the selection of eyes to receive intraocular lenses or epikeratophakia grafts was more critical than those receiving a contact lens, so the latter eyes had a greater propensity to complications requiring additional surgery. The result of this selection is particularly noteworthy for contact lens patients with glaucoma.
Secondary Surgeries Secondary surgeries may be required to maintain the integrity of the eye or optical rehabilitation following cataract surgery. We reviewed our series, and tabulated the number of eyes and the number
TABLE OccurrrrLsrs of Secondary Swgq
Grafts
Epikeratophia
IOL
Lens
3
Following Intraocular
Lens Implantation
by Style of Lens
Iris Suture
Anterior Chamber
Posterior Chamber
TOTAL
(N= 192) EYES (OPS)
(N =40) EYES (OPS)
(N = 53) EYES (OPS)
(N = 285) EYES (OPS)
Discissiori Detached retina Glaucoma Enucleation Examination under anesthesia Nd : YAG laser IOL relocation Explant Other Penetrating keratoplasty
104(152) 2(2) 2(4) 3(3) 2(2) I(I) 13(19) 14(14) 4(4) l(1)
2(2) l(1) l(1) oo-
l(1) 0O-
23(31) o2(2) Oo4(4) l(1) l(1) oo-
129(185) S(3) .‘(7) X(3) “(2) 7(7) 16(22) 16(16) 4(4) l(1)
# EYES (OPS) (WEY ES)
115(202) 60%,
Y(l0) 23%
27(39) 51%
151(250) 53%
Type
of Surger)
ii;;
378
Surv Ophthalmol
34 (5) March-April
1990
BARER, HILES, MORGAN TABLE 4
Best Corrected Visual Acuities and Aphakic Optical Correction Modalities of Consecutive Traumatic Cataracts in Children (1977-I 987)
Ootical Correction Visual Acuity
None #(%)
Glasses #(So) --
I( I;)
2Ol20-40 20/50-100 201200 < 20/200*
l&9:)
I(25) I(25) ~(50)
TOTAL
16
4
Modalitv
Contact Lenses #(So)
IOL #(%)
48(56) 16(19) S(9) 13(15)
67(61) ll(10) 6(5) 26(24)
85
Epikeratophakia #(%) 5(24) 6(32) I(6) 509)
110
17
TOTAL #(%) 120(52) 35(15) I6(7) 61(26) 232
*or unknown
Enucleations were performed on three eyes with IOLs; two had developed intractable secondary glaucoma and one had developed an inoperable retinal detachment and secondary glaucoma. Four contact lens eyes were enucleated because of the same complications. No epikeratophakia eyes have been enucleated. It should be noted that in intraocular lens eyes secondary surgeries were required more frequently in patients with iris suture lenses used between 1974 and 1981 than with anterior chamber or posterior chamber lenses used from 1981 through 1988 (Table 3).““*“S’i
Visual
Results
The visual acuities of the 286 IOL patients in my series (since 1974) were compared with those of other patients who had been operated in the same time period and had received contact lenses or epikeratophakia grafts. Only those children with traumatic or unilateral nontraumatic infantile cataracts are recorded for comparison purposes (Tables 4 SC 5). Overall, 95 (33%) IOL patients achieved corrected visual acuity of 20120 to 20140, and 63 (22%) patients attained 20150 to 20/100. Twenty-seven (10%) patients have 20/200 and 99 (35%) have less
TABLE
than 20/200 visual acuities. Of traumatic cataract patients, 61% achieved 20120 to 20140 acuity, whereas only 16% of the infantile cataract patients achieved this level of vision. The ages at IOL implantation in traumatic versus infantile cataract eyes were compared.g Patients with high levels of pretrauma visual development achieved superior postoperative results unless damage to other ocular structures by the initial trauma prohibited a good visual result. Younger traumatic cataract patients tended to develop amblyopia similar to that found in patients with unilateral infantile cataracts; vigorous treatment is essential to a successful visual result. Patients with infantile cataracts with an early age of onset frequently have very poor postoperative visual results because of obstruction of the visual axis during the crucial sensitive period. Early onset cataracts are also often associated with a higher incidence of other ocular and systemic abnormalities leading to dense deprivation amblyopia. When the visual results achieved by primary and secondary IOL implantation were compared, no significant differences were observed following the two implantation methods in traumatic cataract patients. However, infantile cataract patients with pri-
5
Best Corrected Visual Amities and Aphakic Optical Correction Modalities of Consecutive Unilateral Cataracts (Birth Through 17 Years, 1977-l 987)
Optical Correction
Visual Acuity
Classes #(%)
Contact Lenses #(%)
2Ol20-40 20/50-l 00 201200 < 20/200
---l(100)
10(11) 8(9) 14( 16) 58(64)
TOTAL
1
90
IOL #(%) 28( 16) 52(30) 21(12) 73(42) 174
Modality Epikeratophakia ‘#(%)
TOTAL #(%)
l(3) 2(6) 6(17) 27(75)
39(13) 62(2 1) 41(14) 159(52)
36
301
VISUAL REHABILITATION
OF APHAKIC
mary implants showed a better visual result in the 20/2O to 20/40 category compared to those with secondary implants. Delays following contact lens failure and secondary IOL implantation seemed to enhance amblyopia.”
Conclusion Ophthalmologists managing children with cataracts must consider all of the ramifications of pediatric cataract surgery and their optical rehabilitative problems. The implantation of an intraocular lens (IOL) into the eye of a child is as safe and successful as other methods of aphakic rehabilitation when all of the proper precautions of case selection and surgical technique are utilized. IOLs offer a secondary mode of optical correction fol those contact lens patients who fail to wear their lenses. IOL implantation should be in the armamentarium of all surgeons who treat children with cataracts.
References 1. BinkhorstCD: The iridocapsular clip (four-loop) thalmol
(two-loop) lens and the iris lens in pseudophakia. Tram Am Acad Oph-
Otolaryngol
Binkhorst CD: suiar supported
77t589,
1973
Lens injury in children
treated with iridocapintraocular lenses, in Hiles DA (Ed): Intmor-= ulnr Lent Imphznls in ChddrPn. New York, Grune and Swatton, 1980, pp 8-146 S. Binkhorst CD, Gobin MH: Injuries to the eye with lens opacity in young children. Ophthalmologica 148:169, 1964 4. Binkhorst CD, Nygaard P, Loones LH: Specular microscopy of the cornea1endothelium and lens implant surgery. Am J 2.
Ophthalmol85:597,
4a.Burke
JP, Willshaw
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HE, Young
JDH:
Intraocular
379
CHILDREN
lens im-
IV. Epikeratophakia. KEN-H S. MOKCAN. I M.D., d-leans, Lkisiana Optically, contact lenses are the ideal method of correcting aphakia in children; however, problems with compliance may interfere with rehabilitation. The best fit contact lens is effective only when it is in the eye, and active children can easily dislodge and lose lenses, which is both frustrating and expensive for the parents. Moreover, some young patients have associated conditions that preclude good contact lens correction. A contact lens must move slightly on the cornea for a proper fit. This means that during ocular saccades or in eyes with nystagmus, the optical center of the lens is rarely aligned with the visual axis of the eye. Before epikeratophakia became available, the options for a child with unilateral aphakia who would not or could not wear a contact lens were either aphakic spectacles or secondary implantation of an
plants
for uniocular
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5. Chovce ante&r 78t459,
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P: Correction of uniocular aphakia by means of chamber acrylic implants. 7‘mns Ophthnlmol Sot l[K 1958
techniques and complications associ6. Wiles DA: Indications. ated with intraocular lens implantation in children, in Hiles DA (Ed): In@aoculnr Lens Implants m Childrpu. New York. Crune and Stratton, 1980, pp 189-268 Hiles DA: Intraocular lens in children. .4m 1~lrr~~r~lnr /TNfhznt SotJ 8: 17 1, 1982 Hiles DA: Part 111: Infantile cataracts-aphakic optical correction. Int J Cataract Surg 1:20-29, 1984 Wiles DA: Intraocular lens implantation in children with monocular cataracts. 1974-19XJ. V@th&noic)~q 91: 125 I, 1984 10 Hiles DA, Wallar PH, Biglan AW: Surgery of traumatIc cataracts. Inl Ophthalmol Clin I7:147, 1977 II Hiles DA, Hered RW: Modern intraocular lens implants in children with new age limitations. ,/ (:olnmc/ Ku/ir~rl Surg l3:493-497, 1987 12. Hoffer KJ: Selection of lens power for implantation in infants and children. Am Intmorular Implant Sot J lt49, 1975 13. Maltrman BA, Wagner RS, Capuro AR: Neodymium: YAG laser surgery: Th&trearment &f pediatric car&act disease. .4nn Ophthalmol 18.245, 1986 14. Parks MD, Hiles DA: Management ofinfantile cataracts. ,4m / Ophthalmol fj3:10, 1967 1.5. Scheie HG: Aspiration of congenital or soft cataracts: A new techniaue. Am I Obhthalmol 50:1048. 1960 16. Sheets jH: Lens ilide in implant surgery. Arch (Iphthnlmol 96:145, 1978 17. Sinskey KM, Pate1 J: Posterior chamber intraocular lens implants in children: Report of a series. .4m Intrclonclnr Imfi[ant Sor J 9:157, 1983 17a..lByl~~r D: Editorial: Monocular infantile cataract, intraocular lenses, and amblyopia. BrJ Ophthnlmol7?:857-858, 1989 18. Van Balen AT: Four years’ experience with Binkhorst lens implantation. Am J Ophthalmol 75:755, 1973 Reprint address: David A. Hiles, M.D., Ophthalmology, 3.518 Fifth Ave., Pittsburgh,
Louisiana
Oakland Pediatric PA 152 13.
State University Eye Center, New
intraocular lens. Although there are anecdotal reports of an occasional good result with spectacles, the optical distortion makes this outcome highly unlikely in children who are unilaterally aphakic. Secondary intraocular lens implantation may provide rapid visual rehabilitation, but this procedure has been associated with postoperative complications, including cystoid macular edema, intraocular hemorrhage, postoperative astigmatism, ischemic optic neuropathy, persistent uveitis, uveitis-glaucoma-hyphema (UGH) syndrome, infectious endophthalmitis, retinal detachment, and cornea1 decompensation.’ Secondary intraocular lens implantation in children has been associated with a high rate of secondary surgeries, including membrane removals, lens relocations, and lens removals.“’