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Phakic posterior chamber lens implantation in children with high myopia1
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Phakic posterior chamber lens implantation in children with high myopia Laurence C. Lesueur, MD, Jean L. Arne, MD ABSTRACT Purpose: To evaluate the anatomical and functional results after implantation of a phakic posterior chamber lens (implantable contact lens [ICL™]) to correct high myopia with amblyopia in pediatric patients in whom conventional treatments had failed. Setting: Department of Ophthalmology, Purpan Hospital, University of Toulouse, France. Methods: An ICL was implanted in 5 eyes with amblyopic high myopia in 4 children aged 3 to 16 years. Mean preoperative spherical equivalent refraction was –12.8 diopters (D) (range – 8.0 to –18.0 D) and best spectacle-corrected visual acuity (BSCVA) was counting fingers to 20/200. Mean follow-up was 11.8 months (range 4 to 21 months). Results: Postoperatively, the ICLs appeared to be well tolerated, with no inflammatory reactions, stable intraocular pressure, and good positioning in all eyes. Predictability was ⫹0.5 D (range – 0.5 to ⫹2.0 D) and BSCVA improved, with a gain of 3 or more Snellen lines with recovery of binocular vision in 2 cases and orthotropia in 3 patients. All parents reported an improvement in their children’s quality of life. Conclusion: This preliminary study indicates that ICL implantation is a safe surgical procedure to correct amblyopia resulting from high myopia in children when conventional amblyopia treatments have failed. Longer follow-up of more patients is needed. J Cataract Refract Surg 1999; 25:1571–1575 © 1999 ASCRS and ESCRS
R
efractive surgery is not commonly performed in pediatric patients. Ametropia evolves with age, and most surgeons prefer to postpone surgery for bilateral ametropia until myopia, hyperopia, and astigmatism have stabilized, generally after 20 years of age. Refractive surgery could, however, be considered in children with unilateral high ametropia, particularly if conventional therapy using spectacles or contact lenses has failed.
Accepted for publication July 13, 1999. Reprint requests to Laurence C. Lesueur, MD, Service d’Ophtalmologie, CHU Toulouse Purpan, Place Baylac, 31059 Toulouse Cedex, France. © 1999 ASCRS and ESCRS Published by Elsevier Science Inc.
Despite advances in phakic intraocular lenses (IOLs), which have been increasingly successful in correcting high myopia in adults, there has been no description of their use in pediatric patients. We conducted a prospective study to investigate the clinical outcome in selected children with high myopia who were implanted with phakic posterior chamber lenses to achieve refractive symmetry and treat amblyopia.
Patients and Methods The study group comprised children followed from early childhood in a specialized surgery unit for myopia. 0886-3350/99/$–see front matter PII S0886 –3350(99)00261-8
PHAKIC POSTERIOR CHAMBER LENS IMPLANTATION IN CHILDREN
Inclusion criteria were refractive amblyopia, anisometropia, and unsuccessful conventional amblyopia therapy using various combinations of spectacles, contact lenses, and occlusion therapy. The initial amblyopia treatment was performed by patch occlusion for 6 hours per day and was maintained as long as possible. High myopia in 5 eyes of 4 children was treated with an implantable contact lens (ICL™) (Staar Surgical Inc.). The mean age of the 2 boys and 2 girls was 9.4 years (range 3 to 16 years). In 3 cases, amblyopia in 1 eye was induced by high anisometropia with contact lens intolerance. In the fourth child with bilateral high myopia, spectacles and contact lenses were unsuccessful because of psychological intolerance. Refractive surgery and its expected results in adult patients were explained to the parents and to the children when appropriate, including that these procedures had not been performed in pediatric patients to date and that short- and long-term outcomes of ICLs were unknown in young eyes. All parents provided specific informed consent. Preoperatively, mean spherical equivalent cycloplegic refraction (cyclopentolate 1%) was –12.8 diopters (D) (range – 8.0 to –18.0 D). Best spectacle-corrected visual acuity (BSCVA) ranged from counting fingers to 20/200. The Snellen acuity chart was used to measure visual acuity. Preoperative and postoperative clinical evaluations included slitlamp examination, intraocular pressure (IOP), BSCVA, cycloplegic refraction, quality of life, psychological status, and orthoptic evaluation. The orthoptist consultant in our department performed the visual review of all the children. Binocular vision was assessed with the Wirt and Lang tests. Surgical Procedure The ICL is a single piece of porcine collagen/ HEMA copolymer, referred to as collamer. The optic diameters ranged from 4.8 to 5.5 mm depending on the power. The ICL power was determined by a formula developed by Staar Surgical using the patient’s refraction, keratometry, measured anterior chamber depth, and corneal thickness. White-to-white measurements ⫹ 1 were required to determine the ICL length. 1572
All surgery was performed using general anesthesia. After the pupil was dilated, a 0.8 mm superior paracentesis was performed to inject viscoelastic gel (Ophthalin威) or a similar viscoelastic agent into the anterior chamber. The ICL was implanted through a 3.5 mm temporal corneal tunnel incision with 2 forceps. The haptic edges were placed behind the edge of the iris, and the ICL was centered. The viscoelastic agent was then irrigated and the pupil constricted with acetylcholine chloride (Miochol威). After the clear corneal incision was sutured, a surgical iridectomy was performed through the enlarged paracentesis. Postoperatively, a steroid/antibiotic combination eyedrop was recommended 4 times daily for 1 month. The eye was patched for 1 day, and the child was discharged the morning after surgery with a transparent eye protective screen to be worn for 8 days. The suture was removed 15 days later. All children were given an appropriate amblyopia treatment adapted to the visual gain postoperatively. Patch occlusion during the day varied from 3 to 6 hours in the first month and was maintained thereafter if necessary. Follow-up examinations were at 1, 8, and 15 days, 1, 2, and 3 months, and then as needed. At each visit, the child and parents were questioned about quality of life and symptoms such as eye pain, headaches, halos, and photophobia.
Results Preoperative and postoperative refractive and functional outcomes are given in Table 1. Mean follow-up was 11.8 months (range 4 to 21 months). The ICL was well tolerated in all eyes. No inflammatory reactions were observed, IOPs were normal and stable, and the ICLs remained well centered. A visible space existed between the crystalline lens and the ICL, providing good ciliary sulcus support with anterior ICL vaulting. No pigment deposits were observed in any eye. Postoperative refractive results were highly predictable. Postoperative spherical equivalent refraction ranged from – 0.5 to ⫹2.0 D, with a mean spherical equivalent refraction of ⫹0.5 D. Best spectacle-corrected visual acuity improved, with a gain of 3 or more Snellen lines in the 3 eyes operated on for unilateral anisometropia. The first case gained 6 Snellen lines 19 months after surgery, and
J CATARACT REFRACT SURG—VOL 25, DECEMBER 1999
PHAKIC POSTERIOR CHAMBER LENS IMPLANTATION IN CHILDREN
Table 1. Preoperative and postoperative refractive and functional outcomes Preoperative Patient
Sex/Eye
Age (Years)
SE (D)
BSCVA
Strabismus
ICL Power (D)
1
F/OD
8
⫺12.0
20/200
Exo 20
⫺15.5
2
F/OD
15
⫺18.0
CF
Eso 20
3
M/OS
5
⫺8.0
20/400
Postoperative Follow-up (Months)
SE (D)
BSCVA
Binocular Vision
Strabismus
21
⫺0.5
20/40
Yes
Ortho
⫺19.0
12
⫹1.0
—
—
Ortho
Exo 15
⫺13.5
12
⫹2.0
20/100
Yes
Ortho
4
M/OD
3
⫺8.0
CF
Exo
⫺10.5
10
⫺0.5
20/100
No
Eso 20
2
F/OS
16
⫺18.0
CF
Eso 40
⫺19.0
4
⫹0.5
—
—
Ortho
⫺15.5
11.8
⫹0.5
Mean
9.4
⫺12.8
SE ⫽ spherical equivalent; BSCVA ⫽ best spectacle-corrected visual acuity; ICL ⫽ implantable contact lens; OD ⫽ right eye; OS ⫽ left eye; CF ⫽ counting fingers; Exo ⫽ exotropia; Eso ⫽ esotropia; Ortho ⫽ orthotropia
BSCVA improved from 20/200 preoperatively to 20/40. In the last case, which had bilateral treatment, BSCVA could not be measured because of the girl’s psychological status. Her parents reported improvement in uncorrected visual acuity when she ran and played games. Exotropic and esotropic strabismus decreased in all cases (Table 1). Three children (patients 1, 2, and 3) recovered orthotropia. Patient 4 shifted from exotropia to esotropia immediately after surgery. Two children (patients 1 and 3) recovered binocular vision (Figures 1 to 3). When asked, none of the children or their parents reported eye pain, headaches, halos, or photophobia. The children’s quality of life was clearly improved as evidenced by their participation in school and playtime activities and their psychological status.
Discussion Throughout the world to date, refractive surgery has rarely been performed in pediatric patients. A few stud-
ies report limited numbers of children operated on for anisometropia.1–3 However, some children with high unilateral myopia are predisposed to amblyopia. In a study examining the predictability of amblyopia in ametropic children,4 we reported that the risk of developing amblyopia was significantly higher (P ⬍ .001) in cases of high unilateral myopia, and that in these cases of amblyopia, treatment with spectacles, contact lenses, and occlusion was unsuccessful. The encouraging progress in implanting IOLs in adult phakic eyes 5–7 led us to propose this surgical treatment for anisometropia with amblyopia in children. Three techniques of refractive surgery could be considered. Singh1 reported the results of photorefractive keratectomy (PRK) in 9 patients between 10 and 15 years of age who were treated for unilateral myopia (–5.5 to –17.0 D) and hyperopia (⫹6.0 to ⫹8.0 D) with amblyopia. He noted an improvement in BSCVA in all cases, but haze developed in 2 of the treated eyes. Nano and coauthors2 evaluated the results of PRK in 5 children, aged 10 to 16 years, who were operated on for
Figure 1. (Lesueur) Patient 1 preoperatively (left) and postoperatively (right).
J CATARACT REFRACT SURG—VOL 25, DECEMBER 1999
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PHAKIC POSTERIOR CHAMBER LENS IMPLANTATION IN CHILDREN
Figure 2. (Lesueur) Patient 3 preoperatively (left) and postoperatively (right).
anisometropia (– 4.0 to –11.0 D). Although there was improvement in UCVA and BSCVA, 1 patient developed severe corneal haze. Alio´ et al.3 reported similar results in 6 pediatric eyes treated by PRK. Recently, laser in situ keratomileusis (LASIK) has been performed in pediatric patients. Mene´res reported the results of 10 LASIK procedures in unilateral myopic eyes and 5 in hyperopic eyes of children aged 3 to 12 years. At the 6 month follow-up, there was no regression and BSCVA improved in all eyes. Chan reported the results of bilateral PRK and LASIK in pediatric patients aged 7 to 12 years. He noted 1 case of decreased BSCVA and 1 case of mild corneal haze (P. Mene´res, MD, “LASIK to Correct Ametropia in Children”; T.-K. Chan, MD, “Bilateral PRK or LASIK in Pediatric Patients”; presented at the Symposium on Cataract, IOL and Refractive Surgery, San Diego, California, USA, April 1998). We had several reasons for preferring ICLs to treat anisometropia in children. First, the technique is reversible. Second, since children often rub their eyes, there is less risk of corneal endothelial cell loss with an ICL situated in the posterior chamber than with phakic an-
terior chamber IOLs. Third, the cornea is preserved from haze, allowing later surgical bioptic treatment by PRK or LASIK for evolutive ametropia if needed. Finally, results of ICL implantation8 –10 together with our experience in adults indicate that implantation of a phakic posterior chamber lens is a safe and effective method to surgically correct high myopia. The main complications after ICL implantation in adults are glaucoma and cataract development. In our series, tolerance of the ICL was excellent. There were no inflammatory reactions, although it is known that pediatric eyes often develop uveitis after cataract surgery with IOL implantation. Rosen and Gore8 reported cases of pupillary block glaucoma caused by functional closure of the laser iridotomies. In our pediatric cases, we did not see this complication because we performed an initial surgical iridectomy in all eyes. There was no pigmentary dispersion on the ICL or in the angle, even in the cases with the longest follow-up. Fink and coauthors10 reported 3 cases of crystalline lens opacification, but the mechanism was uncertain. Contact between the lens capsule and ICL, dislocation
Figure 3. (Lesueur) Patient 4 preoperatively (left) and postoperatively (right).
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J CATARACT REFRACT SURG—VOL 25, DECEMBER 1999
PHAKIC POSTERIOR CHAMBER LENS IMPLANTATION IN CHILDREN
of the ICL, accidental touch of the capsule during implantation, laser iridotomies, familial tendency, trauma, metabolic disorders, and high myopia could predispose to cataract formation. Cataract surgery after the ICL was withdrawn was easy to perform, and visual recovery was good. In pediatric cases, cataract formation is an important concern. However, the aim of the treatment is to avoid amblyopia. In case of crystalline lens opacification, cataract surgery could also restore good vision. Finally, in our study, there were no anatomic complications and BSCVA improved in all cases; orthotropia was recovered in 3 cases and binocular vision in 2. Anisometropia is a common cause of amblyopia because correction with spectacles does not have the desired effect in eyes with a refractive difference greater than –3.0 D.11 When spectacles are used, the difference in the image formed by each eye causes a loss of binocular vision and usually amblyopia in the affected eye. Contact lenses are not always possible in children. Lens intolerance, lack of adaptation, and the high cost of contact lenses lead to treatment failure and the development of amblyopia. Bilateral myopia is not an indication for refractive surgery in pediatric cases. However, we performed a bilateral procedure in patient 2. The reasons were intolerance to contact lenses and spectacles in both eyes because of psychological status and the parent’s high degree of satisfaction after the first procedure. The functional outcomes were very satisfying, with recovery of orthotropia. Moreover, parents reported a marked progress in the child’s quality of life after the 2 operations. In conclusion, we believe that implantation of a phakic posterior chamber lens is a safe surgical procedure to correct amblyopia resulting from high myopia in children in whom conventional amblyopia treatments have failed. Our preliminary results are encouraging, showing no anatomic complications, good functional
outcome, and child and parent satisfaction. Longer follow-up of more patients is needed.
References 1. Singh D. Photorefractive keratectomy in pediatric patients. J Cataract Refract Surg 1995; 21:630 – 632 2. Nano HD Jr, Muzzin S, Irigaray F. Excimer laser photorefractive keratectomy in pediatric patients. J Cataract Refract Surg 1997; 23:736 –739 3. Alio´ JL, Artola A, Claramonte P, et al. Photorefractive keratectomy for pediatric myopic anisometropia. J Cataract Refract Surg 1998; 24:327–330 4. Lesueur L, Chapotot E, Arne JL, et al. La pre´dictibilite´ de l’amblyopie chez l’infant ame´trope; a propos de 96 cas. J Fr Ophtalmol 1998; 21:415– 424 5. Baikoff G, Arne JL, Bokobza Y, et al. Angle-fixated anterior chamber phakic intraocular lens for myopia of –7 to –19 diopters. J Refract Surg 1998; 14:282–293 6. Menezo JL, Avino JA, Cisneros A, et al. Iris claw phakic intraocular lens for high myopia. J Refract Surg 1997; 13:545–555 7. Zaldivar R, Davidorf JM, Oscherow S. Posterior chamber phakic intraocular lens for myopia of – 8 to –19 diopters. J Refract Surg 1998; 14:294 –305 8. Rosen E, Gore C. Staar Collamer posterior chamber phakic intraocular lens to correct myopia and hyperopia. J Cataract Refract Surg 1998; 24:596 – 606 9. Sanders DR, Brown DC, Martin RG, et al. Implantable contact lens for moderate to high myopia: phase 1 FDA clinical study with 6 month follow-up. J Cataract Refract Surg 1998; 24:607– 611 10. Fink AM, Gore C, Rosen E. Cataract development after implantation of the Staar Collamer posterior chamber phakic lens. J Cataract Refract Surg 1999; 25:278 –282 11. Townshend AM, Holmes JM, Evans LS. Depth of anisometropic amblyopia and difference in refraction. Am J Ophthalmol 1993; 116:431– 436 From the Department of Ophthalmology, Purpan Hospital, University of Toulouse, Toulouse, France. Presented in part at the XVIth Congress of the European Society of Cataract & Refractive Surgeons, Nice, France, September 1998. None of the authors has a commercial or proprietary interest in any product mentioned.
J CATARACT REFRACT SURG—VOL 25, DECEMBER 1999
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Phakic posterior chamber lens implantation in children with high myopia Laurence C. Lesueur, MD, Jean L. Arne, MD ABSTRACT Purpose: To evaluate the anatomical and functional results after implantation of a phakic posterior chamber lens (implantable contact lens [ICL™]) to correct high myopia with amblyopia in pediatric patients in whom conventional treatments had failed. Setting: Department of Ophthalmology, Purpan Hospital, University of Toulouse, France. Methods: An ICL was implanted in 5 eyes with amblyopic high myopia in 4 children aged 3 to 16 years. Mean preoperative spherical equivalent refraction was –12.8 diopters (D) (range – 8.0 to –18.0 D) and best spectacle-corrected visual acuity (BSCVA) was counting fingers to 20/200. Mean follow-up was 11.8 months (range 4 to 21 months). Results: Postoperatively, the ICLs appeared to be well tolerated, with no inflammatory reactions, stable intraocular pressure, and good positioning in all eyes. Predictability was ⫹0.5 D (range – 0.5 to ⫹2.0 D) and BSCVA improved, with a gain of 3 or more Snellen lines with recovery of binocular vision in 2 cases and orthotropia in 3 patients. All parents reported an improvement in their children’s quality of life. Conclusion: This preliminary study indicates that ICL implantation is a safe surgical procedure to correct amblyopia resulting from high myopia in children when conventional amblyopia treatments have failed. Longer follow-up of more patients is needed. J Cataract Refract Surg 1999; 25:1571–1575 © 1999 ASCRS and ESCRS
R
efractive surgery is not commonly performed in pediatric patients. Ametropia evolves with age, and most surgeons prefer to postpone surgery for bilateral ametropia until myopia, hyperopia, and astigmatism have stabilized, generally after 20 years of age. Refractive surgery could, however, be considered in children with unilateral high ametropia, particularly if conventional therapy using spectacles or contact lenses has failed.
Accepted for publication July 13, 1999. Reprint requests to Laurence C. Lesueur, MD, Service d’Ophtalmologie, CHU Toulouse Purpan, Place Baylac, 31059 Toulouse Cedex, France. © 1999 ASCRS and ESCRS Published by Elsevier Science Inc.
Despite advances in phakic intraocular lenses (IOLs), which have been increasingly successful in correcting high myopia in adults, there has been no description of their use in pediatric patients. We conducted a prospective study to investigate the clinical outcome in selected children with high myopia who were implanted with phakic posterior chamber lenses to achieve refractive symmetry and treat amblyopia.
Patients and Methods The study group comprised children followed from early childhood in a specialized surgery unit for myopia. 0886-3350/99/$–see front matter PII S0886 –3350(99)00261-8
PHAKIC POSTERIOR CHAMBER LENS IMPLANTATION IN CHILDREN
Inclusion criteria were refractive amblyopia, anisometropia, and unsuccessful conventional amblyopia therapy using various combinations of spectacles, contact lenses, and occlusion therapy. The initial amblyopia treatment was performed by patch occlusion for 6 hours per day and was maintained as long as possible. High myopia in 5 eyes of 4 children was treated with an implantable contact lens (ICL™) (Staar Surgical Inc.). The mean age of the 2 boys and 2 girls was 9.4 years (range 3 to 16 years). In 3 cases, amblyopia in 1 eye was induced by high anisometropia with contact lens intolerance. In the fourth child with bilateral high myopia, spectacles and contact lenses were unsuccessful because of psychological intolerance. Refractive surgery and its expected results in adult patients were explained to the parents and to the children when appropriate, including that these procedures had not been performed in pediatric patients to date and that short- and long-term outcomes of ICLs were unknown in young eyes. All parents provided specific informed consent. Preoperatively, mean spherical equivalent cycloplegic refraction (cyclopentolate 1%) was –12.8 diopters (D) (range – 8.0 to –18.0 D). Best spectacle-corrected visual acuity (BSCVA) ranged from counting fingers to 20/200. The Snellen acuity chart was used to measure visual acuity. Preoperative and postoperative clinical evaluations included slitlamp examination, intraocular pressure (IOP), BSCVA, cycloplegic refraction, quality of life, psychological status, and orthoptic evaluation. The orthoptist consultant in our department performed the visual review of all the children. Binocular vision was assessed with the Wirt and Lang tests. Surgical Procedure The ICL is a single piece of porcine collagen/ HEMA copolymer, referred to as collamer. The optic diameters ranged from 4.8 to 5.5 mm depending on the power. The ICL power was determined by a formula developed by Staar Surgical using the patient’s refraction, keratometry, measured anterior chamber depth, and corneal thickness. White-to-white measurements ⫹ 1 were required to determine the ICL length. 1572
All surgery was performed using general anesthesia. After the pupil was dilated, a 0.8 mm superior paracentesis was performed to inject viscoelastic gel (Ophthalin威) or a similar viscoelastic agent into the anterior chamber. The ICL was implanted through a 3.5 mm temporal corneal tunnel incision with 2 forceps. The haptic edges were placed behind the edge of the iris, and the ICL was centered. The viscoelastic agent was then irrigated and the pupil constricted with acetylcholine chloride (Miochol威). After the clear corneal incision was sutured, a surgical iridectomy was performed through the enlarged paracentesis. Postoperatively, a steroid/antibiotic combination eyedrop was recommended 4 times daily for 1 month. The eye was patched for 1 day, and the child was discharged the morning after surgery with a transparent eye protective screen to be worn for 8 days. The suture was removed 15 days later. All children were given an appropriate amblyopia treatment adapted to the visual gain postoperatively. Patch occlusion during the day varied from 3 to 6 hours in the first month and was maintained thereafter if necessary. Follow-up examinations were at 1, 8, and 15 days, 1, 2, and 3 months, and then as needed. At each visit, the child and parents were questioned about quality of life and symptoms such as eye pain, headaches, halos, and photophobia.
Results Preoperative and postoperative refractive and functional outcomes are given in Table 1. Mean follow-up was 11.8 months (range 4 to 21 months). The ICL was well tolerated in all eyes. No inflammatory reactions were observed, IOPs were normal and stable, and the ICLs remained well centered. A visible space existed between the crystalline lens and the ICL, providing good ciliary sulcus support with anterior ICL vaulting. No pigment deposits were observed in any eye. Postoperative refractive results were highly predictable. Postoperative spherical equivalent refraction ranged from – 0.5 to ⫹2.0 D, with a mean spherical equivalent refraction of ⫹0.5 D. Best spectacle-corrected visual acuity improved, with a gain of 3 or more Snellen lines in the 3 eyes operated on for unilateral anisometropia. The first case gained 6 Snellen lines 19 months after surgery, and
J CATARACT REFRACT SURG—VOL 25, DECEMBER 1999
PHAKIC POSTERIOR CHAMBER LENS IMPLANTATION IN CHILDREN
Table 1. Preoperative and postoperative refractive and functional outcomes Preoperative Patient
Sex/Eye
Age (Years)
SE (D)
BSCVA
Strabismus
ICL Power (D)
1
F/OD
8
⫺12.0
20/200
Exo 20
⫺15.5
2
F/OD
15
⫺18.0
CF
Eso 20
3
M/OS
5
⫺8.0
20/400
Postoperative Follow-up (Months)
SE (D)
BSCVA
Binocular Vision
Strabismus
21
⫺0.5
20/40
Yes
Ortho
⫺19.0
12
⫹1.0
—
—
Ortho
Exo 15
⫺13.5
12
⫹2.0
20/100
Yes
Ortho
4
M/OD
3
⫺8.0
CF
Exo
⫺10.5
10
⫺0.5
20/100
No
Eso 20
2
F/OS
16
⫺18.0
CF
Eso 40
⫺19.0
4
⫹0.5
—
—
Ortho
⫺15.5
11.8
⫹0.5
Mean
9.4
⫺12.8
SE ⫽ spherical equivalent; BSCVA ⫽ best spectacle-corrected visual acuity; ICL ⫽ implantable contact lens; OD ⫽ right eye; OS ⫽ left eye; CF ⫽ counting fingers; Exo ⫽ exotropia; Eso ⫽ esotropia; Ortho ⫽ orthotropia
BSCVA improved from 20/200 preoperatively to 20/40. In the last case, which had bilateral treatment, BSCVA could not be measured because of the girl’s psychological status. Her parents reported improvement in uncorrected visual acuity when she ran and played games. Exotropic and esotropic strabismus decreased in all cases (Table 1). Three children (patients 1, 2, and 3) recovered orthotropia. Patient 4 shifted from exotropia to esotropia immediately after surgery. Two children (patients 1 and 3) recovered binocular vision (Figures 1 to 3). When asked, none of the children or their parents reported eye pain, headaches, halos, or photophobia. The children’s quality of life was clearly improved as evidenced by their participation in school and playtime activities and their psychological status.
Discussion Throughout the world to date, refractive surgery has rarely been performed in pediatric patients. A few stud-
ies report limited numbers of children operated on for anisometropia.1–3 However, some children with high unilateral myopia are predisposed to amblyopia. In a study examining the predictability of amblyopia in ametropic children,4 we reported that the risk of developing amblyopia was significantly higher (P ⬍ .001) in cases of high unilateral myopia, and that in these cases of amblyopia, treatment with spectacles, contact lenses, and occlusion was unsuccessful. The encouraging progress in implanting IOLs in adult phakic eyes 5–7 led us to propose this surgical treatment for anisometropia with amblyopia in children. Three techniques of refractive surgery could be considered. Singh1 reported the results of photorefractive keratectomy (PRK) in 9 patients between 10 and 15 years of age who were treated for unilateral myopia (–5.5 to –17.0 D) and hyperopia (⫹6.0 to ⫹8.0 D) with amblyopia. He noted an improvement in BSCVA in all cases, but haze developed in 2 of the treated eyes. Nano and coauthors2 evaluated the results of PRK in 5 children, aged 10 to 16 years, who were operated on for
Figure 1. (Lesueur) Patient 1 preoperatively (left) and postoperatively (right).
J CATARACT REFRACT SURG—VOL 25, DECEMBER 1999
1573
PHAKIC POSTERIOR CHAMBER LENS IMPLANTATION IN CHILDREN
Figure 2. (Lesueur) Patient 3 preoperatively (left) and postoperatively (right).
anisometropia (– 4.0 to –11.0 D). Although there was improvement in UCVA and BSCVA, 1 patient developed severe corneal haze. Alio´ et al.3 reported similar results in 6 pediatric eyes treated by PRK. Recently, laser in situ keratomileusis (LASIK) has been performed in pediatric patients. Mene´res reported the results of 10 LASIK procedures in unilateral myopic eyes and 5 in hyperopic eyes of children aged 3 to 12 years. At the 6 month follow-up, there was no regression and BSCVA improved in all eyes. Chan reported the results of bilateral PRK and LASIK in pediatric patients aged 7 to 12 years. He noted 1 case of decreased BSCVA and 1 case of mild corneal haze (P. Mene´res, MD, “LASIK to Correct Ametropia in Children”; T.-K. Chan, MD, “Bilateral PRK or LASIK in Pediatric Patients”; presented at the Symposium on Cataract, IOL and Refractive Surgery, San Diego, California, USA, April 1998). We had several reasons for preferring ICLs to treat anisometropia in children. First, the technique is reversible. Second, since children often rub their eyes, there is less risk of corneal endothelial cell loss with an ICL situated in the posterior chamber than with phakic an-
terior chamber IOLs. Third, the cornea is preserved from haze, allowing later surgical bioptic treatment by PRK or LASIK for evolutive ametropia if needed. Finally, results of ICL implantation8 –10 together with our experience in adults indicate that implantation of a phakic posterior chamber lens is a safe and effective method to surgically correct high myopia. The main complications after ICL implantation in adults are glaucoma and cataract development. In our series, tolerance of the ICL was excellent. There were no inflammatory reactions, although it is known that pediatric eyes often develop uveitis after cataract surgery with IOL implantation. Rosen and Gore8 reported cases of pupillary block glaucoma caused by functional closure of the laser iridotomies. In our pediatric cases, we did not see this complication because we performed an initial surgical iridectomy in all eyes. There was no pigmentary dispersion on the ICL or in the angle, even in the cases with the longest follow-up. Fink and coauthors10 reported 3 cases of crystalline lens opacification, but the mechanism was uncertain. Contact between the lens capsule and ICL, dislocation
Figure 3. (Lesueur) Patient 4 preoperatively (left) and postoperatively (right).
1574
J CATARACT REFRACT SURG—VOL 25, DECEMBER 1999
PHAKIC POSTERIOR CHAMBER LENS IMPLANTATION IN CHILDREN
of the ICL, accidental touch of the capsule during implantation, laser iridotomies, familial tendency, trauma, metabolic disorders, and high myopia could predispose to cataract formation. Cataract surgery after the ICL was withdrawn was easy to perform, and visual recovery was good. In pediatric cases, cataract formation is an important concern. However, the aim of the treatment is to avoid amblyopia. In case of crystalline lens opacification, cataract surgery could also restore good vision. Finally, in our study, there were no anatomic complications and BSCVA improved in all cases; orthotropia was recovered in 3 cases and binocular vision in 2. Anisometropia is a common cause of amblyopia because correction with spectacles does not have the desired effect in eyes with a refractive difference greater than –3.0 D.11 When spectacles are used, the difference in the image formed by each eye causes a loss of binocular vision and usually amblyopia in the affected eye. Contact lenses are not always possible in children. Lens intolerance, lack of adaptation, and the high cost of contact lenses lead to treatment failure and the development of amblyopia. Bilateral myopia is not an indication for refractive surgery in pediatric cases. However, we performed a bilateral procedure in patient 2. The reasons were intolerance to contact lenses and spectacles in both eyes because of psychological status and the parent’s high degree of satisfaction after the first procedure. The functional outcomes were very satisfying, with recovery of orthotropia. Moreover, parents reported a marked progress in the child’s quality of life after the 2 operations. In conclusion, we believe that implantation of a phakic posterior chamber lens is a safe surgical procedure to correct amblyopia resulting from high myopia in children in whom conventional amblyopia treatments have failed. Our preliminary results are encouraging, showing no anatomic complications, good functional
outcome, and child and parent satisfaction. Longer follow-up of more patients is needed.
References 1. Singh D. Photorefractive keratectomy in pediatric patients. J Cataract Refract Surg 1995; 21:630 – 632 2. Nano HD Jr, Muzzin S, Irigaray F. Excimer laser photorefractive keratectomy in pediatric patients. J Cataract Refract Surg 1997; 23:736 –739 3. Alio´ JL, Artola A, Claramonte P, et al. Photorefractive keratectomy for pediatric myopic anisometropia. J Cataract Refract Surg 1998; 24:327–330 4. Lesueur L, Chapotot E, Arne JL, et al. La pre´dictibilite´ de l’amblyopie chez l’infant ame´trope; a propos de 96 cas. J Fr Ophtalmol 1998; 21:415– 424 5. Baikoff G, Arne JL, Bokobza Y, et al. Angle-fixated anterior chamber phakic intraocular lens for myopia of –7 to –19 diopters. J Refract Surg 1998; 14:282–293 6. Menezo JL, Avino JA, Cisneros A, et al. Iris claw phakic intraocular lens for high myopia. J Refract Surg 1997; 13:545–555 7. Zaldivar R, Davidorf JM, Oscherow S. Posterior chamber phakic intraocular lens for myopia of – 8 to –19 diopters. J Refract Surg 1998; 14:294 –305 8. Rosen E, Gore C. Staar Collamer posterior chamber phakic intraocular lens to correct myopia and hyperopia. J Cataract Refract Surg 1998; 24:596 – 606 9. Sanders DR, Brown DC, Martin RG, et al. Implantable contact lens for moderate to high myopia: phase 1 FDA clinical study with 6 month follow-up. J Cataract Refract Surg 1998; 24:607– 611 10. Fink AM, Gore C, Rosen E. Cataract development after implantation of the Staar Collamer posterior chamber phakic lens. J Cataract Refract Surg 1999; 25:278 –282 11. Townshend AM, Holmes JM, Evans LS. Depth of anisometropic amblyopia and difference in refraction. Am J Ophthalmol 1993; 116:431– 436 From the Department of Ophthalmology, Purpan Hospital, University of Toulouse, Toulouse, France. Presented in part at the XVIth Congress of the European Society of Cataract & Refractive Surgeons, Nice, France, September 1998. None of the authors has a commercial or proprietary interest in any product mentioned.
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