Visual rehabilitation of aphakic children

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II. Contact Lenses. Jam D. BAKER, Michigan, Detroit, Michigan

1990

BARER, HILES, MORGAN

Department of Ophthalmology, Children’s Hospital of

M.D.,

The four currently utilized methods of correcting the refractive error in pediatric aphakia are spectacles, contact lenses, intraocular lenses, and epikeratophakia. Each has its advantages and disadvantages.

and Tillson” found minimal changes in their patients who were fit with hard lenses, and they suggested that the tight fit that was their goal may have influenced this. Spectacle over-refraction must be used with intraocular lenses and epikeratophakia to adjust for an accurate initial refraction and certainly for changes as the eye grows. Spectacles obviously allow for adjustments in refraction, but when used alone they create an unequal image that is unacceptable for treating unilateral aphakia. Contact lenses can be adjusted for a changing refractive error and may be used in unilateral and bilateral cases.

Evaluating the Options The ideal method of pediatric aphakic optical correction should meet the following requirements. 1) It should be changeable to allow for the dynamic changes in refractive error of the child’s growing eye and be capable of correcting for high degrees of hyperopia. 2) It must be able to provide a clear visual image very soon after surgery and continuous good image thereafter. 3) It should not cause irritation and the longterm complication rate should be low. CHANGING

PROMPT AND UNINTERRUPTED

The pediatric aphakic correction should provide a clear visual image with a minimum of delay and little or no interruption. Clearing time of the epikeratophakia graft has improved, but is still a concern and accounts for at least a 4-6 week delay in establishing clear vision. The need for spectacle overcorrection with epikeratophakia and intraocular lenses in some cases is another cause of delay. Spectacles can be worn immediately and without delay, but their effectiveness is limited by optical distortion and reduced visual field, as well as the

REFRACTION

How much does the eye change? Fig. 1 shows the change in contact lens power required over time in a group of my patients who were fitted with silicone lenses. The marked variability of refractive change among children is clearly seen. The refractive changes seen in older children is substantially less than that seen in younger children. Pratt-Johnson

I 0 6.0

4 yrs.

CLEAR

VISUAL IMAGE

2c1.t30 2t5.010(7.4)

10.75 12.00 17.00

3 yrs.

14.00 8.0 10 2: I.(00

24.00

17.00 (7.5) 18.00

25k.5’0 (7.2) 24.50 27.00

18.00

20.00 20.00

(7.5)

26 .( 25.00 (7.5)

28.00 (7.3)

2tI.010 (7.4)

2s).5 0 (7.0)

29 .(10 (7.7)

24!50 (7.2)

25!50 (7.6)

K.K.

SD.

R.S.

R.E.

AC.

8.2.

PATIENTS ( ) = Base Curve Other Numbers = + Power of Contact Lens Fig. 1. Change in power and base curve of silicone contact lens with age in pediatric aphakic eyes.

VISUAL

REHABILITATION

OF APHAKIC

CHILDREN

problem of unequal images in monocular aphakia. The contact lens is fit a week after surgery and occlusion is started the next day.” With daily wear lenses, clear vision is interrupted during non-wear hours, but extended-wear lenses circumvent this problem. There may also be interruptions due to lens loss or intolerance. However, silicone lenses have a relatively low loss rate. TOLERABILITY AND SHORTLONGTERM SAFETY

AND

Of all the modalities for correcting pediatric aphakia, spectacles clearly provide the highest degree of safety. Epikeratophakia and intraocular lens implantation carry the inherent risks of surgery and postoperative infection. Contact lenses can produce irritation, infection, and cornea1 abrasion; however, serious problems can be avoided by proper fitting of the lens, meticulous attention to lens hygiene, and careful monitoring by parents. SUMMARY

OF OPTIONS

Spectacles work well in the bilateral situation, but have limitations when only one eye is aphakic. Contact lenses require parental involvement, may bt lost, and can be irritative to some eyes. Intraocular lenses are still under protocol for patients under eighteen years of age, may be used only in unilateral cases, require a posterior capsule for best support, and are questionably suited for the very young child.‘.“,‘“,“’ Epikeratophakia has the advantage of being an extraocular procedure, but predictability of refractive correction, a small but still present percentage of‘ graft failures, and quality of the visual image in some cases are still concerns.32.‘1”.“.~:! Contact lenses are absolutely indicated in unilateral infantile or congenital cataracts. Proponents of both epikeratophakia and intraocular lenses agree that at least in the first year of life and perhaps for the first three to four years, contact lenses are the indicated treatment. Contact lenses should also be the first choice in bilateral pediatricophakia at almost any age. (Epikeratophakia may be done at a later time as a secondar) procedure.) In the older unilateral cases (4-5 years or over), contact lenses should still be the first choice, but consideration of a primary intraocular lens or secondary epikeratophakia is not unreasonable. The remainder of this paper will deal with contact lenses.

Types of Lenses HARD CONTACT The duced made While

LENS

hard plastic contact lens was first introby Kevin Touhy in 1948. This lens was of polymethylmethacrylate (PMMA). modifications in lens design and fitting

367 techniques have occurred over the years, the basic nature of this hard lens remains unchanged.‘,” Contact lenses represented a major advance, in that they provided the monocular aphakic patient with an optical correction with minimal image size differential between the two eyes, and they offered the bilateral aphakic patient an alternative to thick spectacles. The poor oxygen permeability of the PMMA material limited these lenses to daily wear. In the pediatric aphakic patient, therefore, the parent had to insert, remove, and clean these lenses daily. There were regular periods each day when the aphakic correction was not in place, as well as days when the lens might not be put in place at all because of parental or child illness, etc. The fitting of hard lenses required keratometry information which for young children is obtainable only under general anesthesia.“‘.” The K readings and cornea1 diameter measurements were usually taken prior to the cataract surgery, but at the same sitting to minimize the number of anesthetics and delay in fitting postoperatively.‘” Refitting and subsequent problems with th e initial fit required anesthetics and delays in treatment. Saunders and Ellis”’ reported the fitting of hard lenses by trial and error in a 1981 publication. Development of such techniques might have increased the success of hard lenses, but newer types of lenses with additional benefits became available, largely supplanting hard lenses. It must be acknowledged that a number of fiictors other than the method of optical correction (e.g., age of onset, age at surgery, binocularity vs. monocularity) afrect visual outcome. However, ifone uses visual results of the infantile monocular cataract patient group to help evaluate the efficacy of pediatric aphakic optical correction, the hard PMMA contact lens was not very effective. In fact, most reports in the literature using this lens as the optical correction arc dismal. Frey et alI5 in 1973 reported two out of 21 monocular infantile cataract patients with 20/40 vision. One cataract was noted at birth and the other at six weeks and surgery was completed by age four months.” Pratt-Johnson and ‘l’illsons’~s’ in 198 1 reported good vision in one of three patients operated on by six months of age. The other two patients were 20/400 and 20180. In all of their patients, the contact lens was fitted by the operating surgeon, who also did the follow-up with the aid of his orthoptist associate. III Frey’s patients, the operating surgeon did the follow-up and worked in close association with a contact lens practitioner. ‘l‘hc importance of this personal longterm involvement in optical correction and follow-up by the surgeon can not be stressed enough. .l‘he other series reported at that time kiiled to have any pa-

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1990

tients in the excellent vision range. However, most of them also indicated a much later age of detection and surgery than more recent studies, which are also using different contact lens materials. Thus, inadequate optical correction alone may not be responsible for the poor results reported with the hard PMMA lens, but major problems with therapeutic gaps due to incomplete or non-wear of the hard contact lens are well known. HIGH WATER CONTENT CONTACT

SOFT

LENSES

An extended wear contact lens became available with the development of the high water content soft contact lenses in the early 1970’s.14.33*34,36The increased oxygen permeability required for extended wear was accomplished by the high percentage of water in the lens and the size of the spaces or crevices in the lens filled by water. The high water content and crevices in the lens, however, provide an opportunity for bacterial contamination, necessitating effective sterilization.8 In addition to sterilization, periodic cleaning is required, as lens deposits occur on this as with any extended wear lens. While several different brands have been marketed, Hydrocurve, Permalens, and Sauflon have been most frequently used in children.3~12~‘7~‘s These lenses are large in diameter and flexible and tend to collapse or fold on themselves. This lack of form and large size has made them difficult to insert in the small palpebral opening of children,13 and easy for the child to rub or blink out. The loss rate with this type lens tends to be very high. Beller and Hoyt* report an average of nine lenses used per patient in the first year and Cutler et alI0 had patients lose as many as eight in two weeks and six in five months. Due to the high loss rate and difficulty handling the lens, this lens is now in minimal use, even though it is well tolerated by the eye. The few patients using this lens are those with steep corneas where more rigid lenses have proven unsuccessful. Beller and Hoyt2 reported good results in a group of monocular infantile cataract patients using Hydrocurve and Permalens lenses. They report eight patients, one operated on at 41 days of age and the rest before 20 days. Seven of the patients had visual acuity of 20/40 or better with the eighth at 20180. Their report was the first one showing that good results were possible in monocular infantile cataract patients following early and aggressive treatment in the majority of patients in a series. These authors noted, though, that high loss rate and lens handling difhculties were problems.

SILICONE

CONTACT

LENSES

The first silicone contact lens was manufactured by Danker Labs and made available for investiga-

BARER, HILES, MORGAN

tional use in the late 1970s. The second silicone lens manufacturered was the Dow Corning S&oft lens. These lenses are made of 100% silicone, a macromolecular polymer composed of silica and oxygen, Oxygen permeability is the highest of any lens manufactured to this time, and thermal conduction is excellent. These properties allow minimal disruption of cornea1 metabolism and make the material ideal for extended wear usage. The low water content and absence of interstices for bacterial growth make it possible to use chemical disinfection as well as heat sterilization. Silicone is hydrophobic and the poor wetability of earlier silicone lenses produced an irregular surface where mucus collected and built up. The visual properties of the resultant lens were unsatisfactory. Danker Laboratories used a surface treatment process which gave the lens a hydrophilic surface. This process was initially developed by the Agfa Gevtheaert Chemical Company.‘” This hydrophilic surface breaks down with time, the length of time varying from lens to lens and among individuals. When breakdown occurs, mucus builds up, clarity is reduced, and a new lens is required. The silicone lenses are smaller than the high water content lenses (10.5 to 12.5 mm in diameter) and fairly rigid. This makes them easier to insert and more difficult to rub or blink out, reducing the loss rate.22 Fitting the Silicone Lens

Fitting of the silicone lens is by trial and error, and fluorescein may be used.67s75 Most children under age two require a base curve of 7.50. A lens of this size is placed in the eye and then the Iit evaluated. The manufacturer recommends that a continuous tear/fluorescein film should be visible behind the entire lens; however, lens movement is the most critical and important factor to evaluate.lg The lens should move with blinking and ocular movement. If too much movement is seen, then a steeper lens should be tried. However, in some infants with steep corneas, a flat lens by stain pattern is often seen to be worn well with no cornea1 problems. Often it is the steepest one available and has to be used. These eyes should be watched closely, but many infants are successfully wearing such flat lenses. If little or no movement is seen, a flatter lens must be tried. Early in the use of silicone lenses, the “suck on syndrome” occurred with lack of movement. The lens actually became sucked on to the eye, resulting in cornea1 breakdown with occasional ulcer formation. This problem has not been reported with the Silsoft or later Danker lenses. The early Danker lenses were made from a silicone paste and

VISUAL

REHABILITATION

OF APHAKIC

now they use a silicone oil. The coating is also different from that on the early lenses. Some felt the “suck on syndrome” was due to the capillary attraction of the silicone rubber to the eye. This capillary attraction may also be involved in the lower loss rate of this lens and the occasional difficulty noted in removing the lens. Lens power is determined by refracting through the lens in place on the eye. For children between birth and one year of age, the lens should be fit to over-plus the eye from + 1.50 to + 3.50 diopters. During this period the child is functioning most of the time at a near fixation distance. From age 1 to 4 years, the goal should be to overrefract the child from + .50 to + 1.50 diopters. Starting at age 18 months, an attempt is made to provide bifocal spectacles for near fixation. However, these bifocals are often not worn successfully until after the age of four years. Danker Laboratories will make a lens in almost any power up to + 40.00 and any base curve. Some of the steepest lenses with the highest power arc required in the patients undergoing lensectomy/vitrectomy/membrane peeling for stage V retinopathy of prematurity. Many of these children ideally require a i-40.00 with a base curve of 7.2. Unfortunately, there is a limit in how thick the center of a small steep lens can be. So, although Danker will make almost any size, in a base curve 7.2, the most power we have been able to receive and fit successfully has been a + 34.50. I am sure other limitations of manufacture exist. Danker lenses are marketed by Barnes-Hind Company. The Dow Corning (now Bausch and Lomb) Silsoft lens is available in one diameter, 11.3 mm and three base curves, 7.5, 7.7, and 7.9 for lens powers from + 20 to + 32 in 3 diopter steps. Lenses from + 12 to + 20 are available in 1 diopter steps with base curves of 7.5, 7.7, 7.9, 8.1, and 8.3. Care of the Silicone

369

CHILDREN

Lens

The child under one year of age produces little mucus, and minimal lens cleaning is required. The eyes should be checked by the ophthalmologist with the contact lens in place every 4-6 weeks. The parents are told to remove the lens only if it becomes dirty or the eye becomes red or irritated or has a discharge. Should the child be placed on antihistamines for allergy or a cold, continued lens movement must be closely watched for. Drying of the eye, enhanced with antihistamines, will cause a reduction in lens movement and heighten the concern of developing a sucked-on lens, although this is uncommon with current lenses. If there is any doubt, artificial tears may be used or the lens removed for a couple of’ days. After a year of age, mucus and other secretions in

the eye increase and the lens has to be removed and cleaned on a regular basis. Most are cleaned every one to two weeks, but frequency depends on each individual’s amount of mucus, tear flow, etc. From age 1 to 5 years, the patient should be checked by an ophthalmologist every 3 to 4 months. Visual Results The visual results in treating that most difficult group of monocular infantile cataract patients with this lens are encouraging. We have 6 out of 9 children who see 20140 or better when the cataract was operated on prior to age 4 months, treatment was aggressive, and the follow-up at least four years. Treatment started after the age of four months yields results mostly in the 201200 to 20/800 range. Robb et al report five of 12 patients with 20/70 or better vision.” Drummond et al report 14 patients.” The first seven were treated with either hard or soft contact lenses and the last seven with a silicone lens. Lens compliance was poor in all but one of the first seven and good in all but one of the last seven (the silicone lens patients). The average age at surgery was 3-4 months for the first seven and before one month in all of the last seven. Only one of the first group had 20/50 or better vision, whereas five of the second group had 20150 or better vision. Again, time of onset of therapy along with a contact lens generating good compliance yields the best chance fi>r good vision.” Complications Lem

Loss and Swface Breakdown

The single greatest problem with contact lenses is lens loss. There are very little data available on lens loss with hard contacts, but many comment on the problem. In the high water content soft lenses, Beller and Hoyt stated that the average number of lenses used was nine. Nelson et al report one child lost eight soft lenses but only ti)ur silicone lenses over the same period.“” It is generally agreed that lens loss is much less with the silicone lens than the hydrogel lens. In our practice the average loss is .75 lens per year with a range of 0 to 4. These data were taken from the records of‘20 children who were in silicone lenses for a minimum of three years before the age of five years, Others report up to six lenses lost in one year as a maximum. In our experience, the silicone lens lasts an average of nine months (range, 4-25 months) before the surface breaks down and a new lens is required. Considering replacement for the occasional lost lens and for changes in refractive power, the average lens is actually worn about eight months.

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1990

Intolerance It is the rare patient who is unable to wear contact lenses initially, but the development of lens intolerance is not infrequent and this has led people to intraocular lenses and epikeratophakia. Hiles has reported a 38% overall failure rate of contact lensesz5 In 29 patients fit with silicone lenses, I have found only one patient unable to wear the lens well initially. Two patients have become intolerant at age six years. Most of the other children in the series are between the ages of two and five years. Switching to a gas permeable lens at age 5 to 7 years is often beneficial in terms of comfort and persistent lens clarity. Of the first six patients fit with the silicone lens (Danker), one developed a cornea1 ulcer and a small scar was left after healing. The parents had noted that the eye was red for a couple of days, but did not remove the lens. This child sees well and continues with her silicone lens on a daily wear basis. This incident probably started from sucked-on lens syndrome. Cornea1 abrasions with hard lenses occur infrequently. Good results are achieved when the lens is removed and the abrasion is treated according to usual methods. The open matrix of the soft lens can be a source of infection, and careful cleaning is important. Most infections seem to be associated with home-prepared saline solutions and these should be avoided. Acanthamoeba keratitis, the most severe infection associated with contact lenses, is increasingly reported in wearers who use homemade saline solutions to clean their lenses. In general, other than the eye becoming lens intolerant for unknown reasons, contact lenses are safe and complications are minimal.

Summary and Conclusions For purposes of selecting the appropriate mode of optical correction, pediatric aphakics can be divided into four groups, according to age and laterality. In the unilateral and bilateral infantile patient, contact lenses are the only real choice other than spectacles in some of the bilateral cases. In the older bilateral cases, contacts and to some extent, spectacles are the best choice. In the older child with a unilateral cataract, the choice widens somewhat. A contact lens is still the safest, but as the age of the child increases, consideration for a primary intraocular lens or secondary epikeratophakia increases also. The silicone contact lens in the last ten years has been the salvation of the pediatric ophthalmologist treating aphakia. Neither implanted lenses or epikeratophakia have produced good visual results in this youngest group of children.25z2” The availability

BAKER, HILES, MORGAN of an extended wear, easily fitted, well-tolerated contact lens with a low loss rate has been crucial. In older children who develop a cataract or have vision problems as a result of intensive therapy using a contact lens, there may be other considerations for initial or continued aphakic correction, but up to age five years, the choice is clearly an extended wear soft contact lens. Tolerance of the silicone lens is poor in adults and good in children. Adults complain of its not being comfortable, but children under age six wear it well. To the credit of the manufacturers, they appreciate the crucial place of these lenses in pediatric aphakic therapy and continue to make them available despite the very small market.

References 1. Baxter PL: The use of contact lenses in infants. Trans Ophthalmol Sot UK 83:41-50, 1963 2. Beller R, Hoyt CS, Marg E, et al: Good visual function after neonatal surgery for congenital monocular cataracts. Am. J Ophthalmol 91:559, 1981 DM: Clinical evaluation of continuous3. Binder PS, Worthen wear hydrophilic lenses. Am J Ophthalmol83:549-553, 1977 CD, Gobin MH: Treatment of congenital and 4. Binkhorst juvenile cataract with intraocular lens implants (pseudophakoi) Br J Ophthalmol 54.759-65, 1970 JH, Harley RD: The roto-extractor in pediatric 5. Calhoun ophthalmology. Trans Am Ophthalmol Sot 73:292-305, 1975 lenses for infants. Am J Ophthalmol 6. Cassady JR: Contact 56:305-307, 1963 PA: Surgery of congenital cataract. Trans Am Acad 7. Chandler Ophthalmol Otolaryngol 72341-54, 1968 IJ: Infective keratitis in soft contact 8. Cooper RL, Constable lenses wearers. Br J Ophthalmol 61:250-254, 1977 ofposterior lenticonus 9. Crouch ER, Parks MM: Management complicated by unilateral cataract. Am J Ophthalmol 85:503-508, 1978 wear contact 10. Cutler SI, Nelson LB, Calhoun JH: Extended lenses in pediatric aphakia. J Pediatr Ophthalmol Strabismus 22:86-91, 1985 GT, Scott WE, Keech RV: Management ofmon11. Drummond ocular congenital cataracts. Arch Ophthalmol (in press) wear contact lenses in young 12. Ellis P: The use of permanent aphakic children. Contact Lens J 5:23-26, 1977 (soft) contact lenses to 13. Enoch JM: The fitting of hydrophilic infants and voung children. Contact Lens Med Bull (j-4):4 1. 1972 ’ which need to be considered 14. Enoch JM: Fitting parameters when designing soft contact lenses for the neonate. Con,tnct Intraocular”L.& Med J 5:31-37, 1979 D, Wyatt D: Re-evaluation of monocular 15. Frey T, Friendly cataracts in children. Am J Ophthalmol 76r381, 1973 16. Friendly DS, Oldt NW: Contact lenses for aphakic children. Int Ophthalmol Clin 17:205-Z 19, 1977 JA, Boothe RG, Chandler CV, et al: Extended 17. Gammon wear soft contact lenses for vision studies in monkey. Invest Ophthalmol Vis Sci 26:1636-1639, 1985 wear of gas permeable contact lenses 18. Garcia G: Continuous in aphakia. Contart Intraocular Lens Med J 2:29, 1976 wear of soft con19. Gasset AR, Lobo L, Houde W: Permanent tact lenses in aphakic eyes. Am J Ophthalmol 831115-120, 1977 G, Marg E: Long-term visual 20. Gelbert SS, Hoyt CS, Jastrebski results in bilateral congenital cataracts. Am J Ophthalmol 933t615, 1982 of aphakic infants with con21. Gould H: Visual rehabilitation tact lenses. J Pediatr Ophthalmol Strabismus 67:203-206, 1969 J: Use of silicone lenses in infants and children. 22. Gurland Ophthalmology 86: I 599-l 604, 1979

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,

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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.

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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-