Cataract Extraction and Primary Hydrophobic Acrylic Intraocular Lens Implantation in Infants

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1 Cataract Extraction and Primary Hydrophobic Acrylic Intraocular Lens Implantation in Infants Samuray Tuncer, MD, Ahmet Gucukoglu, MD and Nilufer Gozum, MD Purpose: We sought to report the incidence of visual axis opacification and to evaluate the complication and reoperation rates after intraocular lens implantation in infants. Methods: Twenty-one infants (31 eyes) who had cataract extraction with primary hydrophobic acrylic IOL implantation between October 1996 and May 2002 were reviewed. Posterior capsule was left intact in 14 eyes (group A); posterior capsulorrhexis or capsulotomy with anterior vitrectomy was performed in 17 eyes (group B). Complication and reoperation rates were compared with an age-matched control group of 17 patients (33 eyes) who were left aphakic after pars plicata lensectomy. Mean follow-up period was 41 months (range, months) in group A, 37 months (range, months) in group B, and 52 months (range, 7 97 months) in the control group. Results: Mean age of the patients was 6.8 months (range, 3 10 months) in group A, 8.9 months (range, 3 18 months) in group B, and 4.9 months (range, 1 15 months) in the control group. Visual axis opacification was significantly higher in group A (86%) when compared with group B (17.6%; P ). No significant difference was found in terms of pupillary irregularities and peripheral anterior synechiae formation between pseudophakic and aphakic group (P 0.43 and P 0.306, respectively), whereas pigment dispersion and fibrinous reaction were significantly more common in the pseudophakic group (P 0.002). Serious complications, such as retinal detachment, pseudophakic bullous keratopathy, and secondary glaucoma, did not develop in any eye. Reoperation rate was significantly higher in group A (78%) when compared with group B (17%) and the control group (12%; P and P , respectively). Conclusions: Visual axis opacification requiring a reoperation was significantly more common in patients with an intact posterior capsule. To decrease the reoperation rate and maintain a clear visual axis, posterior capsulorrhexis with anterior vitrectomy should be performed. Even although early complications were quite frequent, serious late complications were not encountered in any eye. Therefore, under appropriate conditions, IOL implantation is a suitable alternative in infants. (J AAPOS 2005;9: ) From the Department of Ophthalmology, Istanbul University, Istanbul Faculty of Medicine, Istanbul, Turkey. Presented at the XIII. Afro-Asian Congress of Ophthalmology, June 21, 2004, Istanbul, Turkey. Submitted August 6, Revision accepted December 30, Reprint requests to: Samuray Tuncer MD, Istanbul University Istanbul Faculty of Medicine, Department of Ophthalmology, Capa 34390, Istanbul, Turkey ( sbtuncer@ yahoo.com). Copyright 2005 by the American Association for Pediatric Ophthalmology and Strabismus /2005/$ doi: /j.jaapos C ataracts are one of the most common treatable causes of visual impairment during infancy. The prevalence of pediatric cataracts is cases per 10,000 infants. 1 Although many of these cataracts are congenital, the age of onset usually cannot be determined. Therefore, all cataracts that develop during the first 18 months of life can be referred to as infantile cataracts. 1 With advances in microsurgical techniques, viscoelastic agents, and IOL design, the use of IOLs for the rehabilitation of pediatric aphakia has become increasingly common in recent years and now represents the standard optical treatment for older children. 2-6 However, implanting an IOL in the eye of an infant is still controversial because it poses several challenging points. Firstly, rapid eye growth causes marked axial and refractive changes (myopic shift). 7-9 Second, postoperative complications requiring reoperations tend to occur more frequently because of increased tissue reactivity. 10 Finally, concern exists about the unknown risks of an IOL during a long life span. 11 Several reports have been published that include children younger than 18 months of age with primary IOL implantation. 2,6,7,9,12-21 However, articles dealing exclusively with infantile age group are limited ,22 In this study, we aimed to report the incidence of visual axis opacification and to evaluate the complication and reoperation rates after cataract surgery and primary hydrophobic acrylic IOL implantation in infants. MATERIALS AND METHODS The medical records of 31 consecutive eyes of 21 infants between 3 and 18 months of age who had cataract extrac- 250 June 2005

2 Volume 9 Number 3 June 2005 Tuncer, Gucukoglu, and Gozum 251 tion and primary hydrophobic acrylic IOL implantation between October 1996 and May 2002 were reviewed retrospectively. Age at surgery (in months), laterality, type of cataract (total white or partial cataract), postoperative complications, the need for additional surgery, final visual acuity, and follow-up period were recorded. The study protocols and informed consent forms were reviewed and approved by an appropriate institutional review board at our institution, and signatures of all parents/guardians were obtained on the consent forms approved by the board. Preoperatively, all patients had complete ophthalmic examination. The type of cataract was determined by slitlamp examination. The corneal diameter, keratometry, and biometric axial length measurements were taken. We performed B-scan ultrasonography in eyes in which fundus was not visible. The SRK II formula was used to select the IOL power needed to achieve emmetropia. All patients were undercorrected by 20 30% in consideration of a myopic shift of the growing eye. 1,7,23,24 Cyclopentolate 1% and phenylephrine 10% eyedrops were administered every 30 minutes for 3 hours before surgery to dilate the pupil. The patients were operated under general anesthesia by one surgeon (A.G.). In infants with bilateral cataracts, both eyes were operated in the same session with 2 different sets of surgical instruments. The surgical technique was as follows: 2 side-ports were made, and the anterior chamber was filled with viscoelastic substance (Viscoat, Alcon, Fort Worth, TX). Then, superiorly localized corneal tunnel was fashioned. An initial opening in the anterior capsule was made, and a 5- to 6-mm-diameter continuous curvilinear anterior capsulorrhexis was performed. The lens material was aspirated by 2-port automated irrigation/aspiration, leaving an empty bag with no residual cortical material. In 14 eyes that were operated between October 1996 and July 1998, the posterior capsule was left intact (group A). In remaining 17 eyes that were operated later until May 2002, posterior capsulorrhexis or capsulotomy with anterior vitrectomy was performed (group B). In all 31 eyes, a foldable hydrophobic acrylic IOL (AcrySof, MA30BA model; Alcon) with an overall diameter of 12.5 mm and optic plate of 5.5 mm was implanted in the bag or sulcus. Optic capture of the IOL was not performed in any eye. After IOL implantation, the residual viscoelastic substance was removed with the automated irrigation/aspiration. The wound was closed with one 10-O nylon suture. At the conclusion of the procedure, subconjunctival gentamicin and dexamethasone were injected into the inferior cul-de-sac, and antibiotic ointment was applied. Postoperatively, all patients received prednisolone acetate 1% 6 to 8 times a day for 2 weeks and 4 times a day for an additional 2 weeks, after which it was slowly tapered. Tobramycin 0.3% was administered 4 times a day for 2 weeks, and topical cyclopentolate 1% was used twice a day for 1 month to prevent synechiae. The patients were examined postoperatively at first day, first week, first month, and at intervals appropriate to patients needs thereafter. They also were examined under general anesthesia when necessary. Slit-lamp examination, funduscopy, retinoscopy, and ocular motility testing were conducted. The intraocular pressure (IOP) was not measured routinely. In some cooperative patients, IOP could be recorded with applanation tonometry. However, in most of the patients, the diagnosis of glaucoma was based on clinical and observational signs, such as epithelial edema, photophobia and/or epiphora, and glaucomatous cupping on fundus examination. If any of these signs or symptoms of increased IOP was observed, an examination under general anesthesia was performed. Spectacles were prescribed and changed if needed. Patching was applied to minimize the influence of amblyopia. Final visual acuity was taken on a Snellen scale of 20/200 to 20/20 whenever it was possible. The patients in whom Snellen visual acuity could not be assessed, fixation-preference testing was evaluated. When a large myopic shift occurred, causing intolerable anisometropia, IOL exchange was considered. Complication and reoperation rates also were compared with age-matched group of 17 consecutive patients (33 eyes) who were left aphakic after pars plicata lensectomy (control or aphakic group). The patients were operated by the same surgeon (A.G.) under general anesthesia between November 1992 and October The mean follow-up period was months (range, 7 97 months). Statistical analysis in this study included chisquare test and Kaplan-Meier survival analysis. A P 0.05 was considered statistically significant. Statistical analyses were performed using SPSS program for Windows (SPSS Institute, Chicago, IL). RESULTS The clinical features of pseudophakic infants are shown in Table 1. Of 21 patients included in the study, 10 were male and 11 were female. Eleven patients had unilateral and 10 had bilateral cataract. Totally white cataracts were present in 14 eyes, and partial cataracts obscuring the visual axis were present in 17 eyes. Patients age at surgery ranged from 3 to 18 months (mean, months). Mean age of the patients was 6.8 months (range, 3 10 months) months in group A, 8.9 months (range, 3 18 months) in group B, and 4.9 months (range, 1 15 months) in the control group. The mean follow-up period was 41 months (range, months) in group A, 37 months (range, months) in group B, and 52 months (range, 7 97 months) in the control group. The mean axial length was mm (range, mm). Although the mean power of the IOL needed to achieve emmetropia was diopters (D) (range, D), the mean power of the implanted IOLs was D (range, D).

3 252 Tuncer, Gucukoglu, and Gozum Volume 9 Number 3 June 2005 TABLE 1. Clinical features of pseudophakic infants Patient no./sex Eye Age at surgery (months) Type of cataract Postoperative complications Reoperation(s) Group A (Pseudophakic Posterior capsule intact, n 14)* Final visual acuity Follow-up period (months) 1/M OD 5 Total PCO PC AV 20/25 61 OS 5 Total PCO PC AV 20/ /F OD 7 Total PCO, PD, FR PC AV 20/ OS 7 Total PCO, PD, FR, PI PC AV 20/ /F OD 10 Zonular PCO PC AV 20/ /M OD 9 Anterior polar PCO, PD, PI, PS PC AV PP 20/ OS 9 Anterior polar PCO PC AV PP 20/ /F OD 3 Total PCO, PD, FR, PI, PAS, PS, VO PC AV PP, AV 20/ /F OD 10 Total PI, IA 20/32 29 OS 10 Total 20/ /M OD 5 Zonular PCO, FR PC AV 20/63 22 OS 5 Zonular PCO, FR, PI 20/ /M OD 5 Total PCO, FR, PS PC AV C, S, M 26 OS 5 Total PCO PC AV C, S, M 26 Group B (Pseudophakic Posterior capsulorrhexis/capsulotomy AV, n 17) 1/M OS 4 Total VO* AV 20/ /F OS 18 Total VO*, PD AV 20/ /F OD 7 Zonular PI 20/32 30 OS 7 Zonular 20/ /M OD 6 Zonular 20/32 57 OS 6 Zonular 20/ /F OS 4 Zonular PI, PAS 20/ /M OD 18 Total PI, PAS 20/ /M OD 3 Zonular C, S, M 10 8/M OS 7 Zonular PD IOL exchange 20/ /F OD 4 Total VO, FR, PI, PS AV C, S, (U)M 10 OS 4 Total FR, PS C, S, M 10 10/F OS 8 Zonular PI, IA 20/ /F OD 3 Zonular PD, PI, PAS, transient IOP rise C, S, M 13 OS 3 Zonular C, S, M 13 12/M OS 18 Posterior polar PD, PS 20/ /F OD 16 Posterior polar 20/50 52 * n is the number of eyes. Visual axis opacification coupled with lens reproliferation/regrowth. Anterior vitrectomy was performed for the treatment of vitreous opacification that developed 26 months after the 1st reoperation. AV-anterior vitrectomy (limbal); C-central; F-female; FR-fibrinous reaction; IA-iris atrophy; M-male; OD-right eye; OS-left eye; PAS-peripheral anterior synechiae; PC-posterior capsulectomy; PCO-posterior capsule opacification; PD-pigment dispersion; PI-pupillary irregularities; PP-pupilloplasty; PS-posterior synechiae; S-steady; (U)M-(un)maintained; VO-vitreous opacification. FIG 1. Flow diagram showing the status of the central visual axis in pseudophakic eyes. Secondary cataract formation after posterior chamber IOL implantation in 31 eyes of 21 infants is shown in Figure 1. Of 14 eyes in which the posterior capsule was left intact (group A), 12 eyes (86%) developed posterior capsule opacification (PCO) after a mean period of 7 months (range, 3 weeks to 17 months) postoperatively (Figure 2). The rate of PCO was 15% after 3 months, 43% after 6 months, 79% after 1 year, and 86% after approximately 18 months. Lens reproliferation coupled with PCO occurred in 6 eyes (19.3%; Table 1). In 11 of the 12 eyes, reoperation to clear the visual axis was performed through 2 limbal ports after a mean period of 11 months (range, 5-20 months) from the first procedure. In 1 patient, it was possible to perform retinoscopy through the pupil, so we left it intact for observation. In 1 eye (group A, patient no. 5; Table 1), anterior vitreous opacification forming a pupillary membrane required pars plana anterior vitrectomy 26 months after the first reoperation. Of 17 eyes in which posterior capsulorrhexis or capsulotomy with anterior vitrectomy was performed (group B), visual axis remained

4 Volume 9 Number 3 June 2005 Tuncer, Gucukoglu, and Gozum 253 TABLE 3. Reoperation rates in pseudophakic vs aphakic group (chisquare test) Group Number of reoperated eyes/ total number of eyes % Group A 11/14 78 Group B 3/17 17 Control 4/33 12 Group A-B, P.0011; Group A-Control, P.0001; Group B-Control, P.67. TABLE 4. Final visual acuity in pseudophakic infantile eyes with unilateral and bilateral cataract Laterality <20/200 20/200 20/50 >20/50 Fixationpreference Unilateral (n 11)* Bilateral (n 20) * n is the number of eyes. FIG 2. The clarity of the visual axis in patients with intact posterior capsule (Kaplan-Meier survival analysis). TABLE 2. Complication rates in pseudophakic vs aphakic group (chisquare test) A&B group (n 31) Control group (n 33) P Value Early complications Pigment dispersion * Fibrin reaction in anterior chamber * Pupillary irregularities Peripheral anterior synechiae Late complications Retinal detachment 0 0 Pseudophakic bullous keratopathy 0 0 Secondary glaucoma 0 0 *Statistically significant (P.05). clear in 14 eyes (82.4%). Reoperation was performed in 3 eyes (17.6%) with vitreous opacification. Using chi-square test, the complication rates were compared with an age-matched control group of 17 patients who were left aphakic at the time of surgery (Table 2). No significant difference was found in early complication rates in terms of pupillary irregularities and peripheral anterior synechiae formation between pseudophakic and aphakic group (P.43 and P.306, respectively), whereas pigment dispersion and fibrinous reaction were significantly more common in pseudophakic group (P.002). Serious late complications, such as retinal detachment, pseudophakic bullous keratopathy, and secondary glaucoma did not develop in any eye in both groups. Less frequently encountered complications in pseudophakic group were iris atrophy in 2 eyes; transient IOP rise in 1 eye and large myopic shift requiring IOL exchange in 1 eye (Table 1). Complication rates also were compared by the frequency of reoperations using chi-square test (Table 3). Although the reoperation rate was significantly higher in group A when compared with group B and the control group (P.0011 and P.0001, respectively), no significant difference was found between group B and the control group (P.67). Only 1 IOL exchange was necessary because of large myopic shift with intolerable anisometropia and severe amblyopia (group B, patient no. 8; Table 1). Her initial axial length was and her immediate postoperative refraction was 4.00 D sphere. An IOL exchange was performed when her axial length was and her refraction, 5.00 D 2.5 years later. Visual acuity could be evaluated using a Snellen scale in 24 eyes (77.5%) and was limited to fixation-preference testing in remaining 7 eyes (22.5%; Table 1). We found that the final visual acuity was less than 20/50 in 10 eyes (100%) with unilateral cataract and in 4 eyes (29%) with bilateral cataract. However, final visual acuity greater than 20/50 was achieved in 10 eyes (71%) with bilateral cataract and none of the eyes with unilateral cataract (Table 4). DISCUSSION During the early phases of life, an infantile cataract blurs the retinal image and also disrupts the development of the central visual pathways. 1 This cataract may cause significant visual deprivation later in life. Therefore, early treatment and prompt visual rehabilitation can result in good visual outcomes Aphakic optical correction has been undertaken with spectacles and contact lenses. However, these 2 treatment modalities have different disadvantages. On the one hand, spectacles can be used to correct bilateral aphakia but are unsuitable for unilateral aphakia because they induce aniseikonia. In addition, they are cosmetically undesirable and induce optical aberrations. On the other hand, contact lenses may be used in patients with unilateral or bilateral aphakia. However, they require intensive care on the part of the patients and parents, who may also be burdened with amblyopia therapy and increased expenses for lens replacement. Moreover, they can be lost during the therapy and carry the risk of infection. 15,29

5 254 Tuncer, Gucukoglu, and Gozum Volume 9 Number 3 June 2005 An alternative to external means of optical correction is IOL implantation. 15 In the late 1970s, Hiles 30 pioneered the implantation of IOLs in children after cataract surgery. IOLs are now the standard optical treatment for older children after cataract surgery. Although their use during infancy is still controversial, our results confirm the findings of other studies, 31,32 which have shown that modern surgical techniques and instrumentation have made it technically feasible to implant an IOL in an infantile eye. The criteria for IOL implantation in infants with respect to age is not yet determined. Although some authors 15,33 prefer 1 year of age, others 34 prefer 2 years of age as the lower limit for IOL implantation. Knight- Nanan et al. 6 implanted IOLs successfully in 6 eyes of patients with congenital cataracts who were between 4 and 28 weeks of age. In our clinic, we prefer implantation of IOLs in the management of all infantile cataracts under suitable conditions. The smallest patient in our series is 3 months of age. The surgical approach to cataract extraction and IOL implantation in infants requires careful management of the posterior capsule and the anterior vitreous. In infants, leaving the posterior capsule intact after lens implantation in the capsular bag predisposes to an unacceptably high incidence of secondary cataract formation. 35,36 The reported incidence of PCO has varied between 51% and 100%, and is a significant cause of deprivational amblyopia. 37 Oliver et al 2 found an opacification rate of 44% in infants and juveniles in the first 3 months after in-the-bag IOL implantation with an intact posterior capsule. Knight-Nanan et al 6 and Markham et al 31 reported PCO in 95.8% and 87.5% of cases, respectively. In our series, we found a gradual increase in PCO over the course of time. The PCO rate was 15% after 3 months, 43% after 6 months, 79% after 1 year and 86% after approximately 18 months. Moreover, the anterior vitreous face is more reactive and the postoperative inflammatory response is more severe in infants. 18,38 Vasavada and Chauhan 22 showed that a posterior capsulectomy without anterior vitrectomy did not prevent a secondary membrane from developing. Koch and Kohnen 39 found a secondary cataract formation rate of 88% in eyes that had posterior capsulorrhexis without vitrectomy. Therefore, many surgeons believe that a moderately aggressive anterior vitrectomy is always necessary along with a sufficient primary posterior capsulotomy (4.0 to 5.5 mm) to maintain a clear visual axis and to decrease the reoperation rate In our series, we found central opacification in 17% of eyes managed with posterior capsulotomy/capsulorrhexis and anterior vitrectomy. We think that this might have been caused by the small posterior capsular opening and/or limited anterior vitrectomy. Lens regeneration into the pupillary space may occur after the surgery. It is known to arise from epithelial cells migrating from the anterior lens capsule to the equatorial bow region. 37 In a study by Lambert et al 36 it was reported in 28.6% of the pseudophakic eyes. In our series, we detected lens reproliferation coupled with posterior capsule opacification in 6 of 31 eyes (19.3%). When choosing an IOL for implantation in infants, special care must be given to the smaller size of the globe and to selecting a biomaterial that will be compatible with the eye for a lifetime. Dahan and Drusedau 7 reported good results with 1-piece posterior chamber IOLs having an overall diameter of 10.5 mm and an optic plate of 5.5 mm. Wilson et al 42 recommended that capsular IOLs be 10 mm in children less than 2 years old and mm in children more than 2 years old. However, newer IOLs are more flexible while retaining their memory characteristics, making downsizing less necessary. Hutchinson et al 11 reported that the flexible haptics of the acrylic IOL allow implantation of an adult-sized lens into an infant eye with minimal trauma and only moderate capsular bag distortion. Many surgeons now use high-biocompatible foldable acrylic lenses, which allow small-incision surgery and thus decreased postoperative inflammation, astigmatism, and endothelial damage. 43 In all 31 eyes included in our study, we implanted a foldable hydrophobic acrylic IOL with an overall diameter of 12.5 mm and optic plate of 5.5 mm. We experienced easy implantation and good centration with minimal trauma and capsular distortion after a mean follow-up period of 39 months. The choice of the appropriate IOL power in infants is the most challenging issue. The general concept is that the IOL power to be implanted in the infantile period should aim initial hypermetropia, anisometropia, or both should be acceptable and correctable by spectacles to maximize visual acuity and minimize the risks of amblyopia. In this regard, authors generally recommend undercorrecting the emmetropic calculation by 20% in infants. 1,7,23,24 Dahan and Drusedau also recommend using axial length when is choosing the appropriate IOL dioptric power for infants, 7 whereas Flitcroft et al 16 suggest aiming 6 diopters of initial hypermetropia in these eyes. Spectacle power then can be adjusted throughout childhood according to the patient s refractive development. All these calculations aim for emmetropia in a child 6 years or older. In our small series, all of our patients were undercorrected by 20 30%. Only one IOL exchange was necessary because of large myopic shift with intolerable anisometropia and severe amblyopia. However, a myopic shift later on life is to be expected. The rate of complications and reoperations tend to be higher in infants when compared with older age groups. Lambert et al 10 reported that 72% of infants younger than 6 months of age developed several postoperative complications requiring reoperations. In a recent study by Trivedi et al, 44 a secondary surgical procedure was required in 37.9% of eyes to maintain a clear visual axis in infants during the first year of life. In our study, we found that early postoperative complications such as fibrinous reaction and pigment dispersion were more frequent after IOL implantation. Fibrinous reactions occurred in 6 eyes

6 Volume 9 Number 3 June 2005 Tuncer, Gucukoglu, and Gozum 255 in group A and in 2 eyes in group B. This difference is possibly related to high reactivity of the infants eye, which may be attributed to surgical trauma and less extensive use of viscoelastics because those eyes in group A were operated earlier. However, it is questionable whether this complication is related to leaving the posterior capsule intact. Our reoperation rate was higher in infants in whom the posterior capsule was left intact (78%) when compared with infants who had posterior capsulorrhexis or capsulotomy with anterior vitrectomy and who were left aphakic during surgery (17% and 12%, respectively). We performed our anterior vitrectomy through 2 limbal side ports, as advocated by MacKool and Chhatiawala. 17 This way of approach avoids the complications associated with pars plana entry side. In contrast, another study 11 could not show any significant difference in complication and reoperation rates between pseudophakic and aphakic infants. Even though glaucoma has been reported to develop in 6 24% of eyes after infantile cataract surgery, 45 we did not detect any case with secondary glaucoma as a late complication. Although pupillary block and acute angleclosure glaucoma often occur in the early postoperative period, open angle glaucoma may arise many years later, emphasizing the need for lifelong follow-up of these patients. 46 Thus, we may expect secondary glaucoma in forthcoming years. Moreover, other serious late complications, such as retinal detachment, pseudophakic bullous keratopathy, did not develop in any eye. We need a longer follow-up period to observe these complications. The visual outcomes of infantile cataract surgery are more encouraging in bilateral cataracts. We found that the final visual acuity greater than 20/50 could be achieved in 10 eyes (71%) with bilateral cataract, and none of the eyes with unilateral cataract. New surgical techniques, more aggressive amblyopia therapy, and family motivation will allow us better visual outcomes. In conclusion, leaving the posterior capsule intact causes high incidence of PCO. In our series, we found a PCO rate of 86% in patients with intact posterior capsule. IOL implantation during infancy is associated with several postoperative complications requiring reoperations. To decrease the reoperation rate and to maintain a clear visual axis, primary posterior capsulorrhexis along with anterior vitrectomy should be performed in each case. This study also emphasizes that IOL implantation in infants strongly aids early visual rehabilitation and such that an early approach does not cause serious late postoperative complications. Therefore, under appropriate conditions, IOLs is a suitable alternative. 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7 256 Tuncer, Gucukoglu, and Gozum Volume 9 Number 3 June Birch EE, Swansson WH, Stager DR, Woody M, Everett M. Outcome after very early treatment of dense congenital unilateral cataract. Invest Ophthalmol Vis Sci 1993;34: Cheng KP, Hiles DA, Biglan AW, Pettapiece MC. Visual results after early surgical treatment of unilateral congenital cataracts. Ophthalmology 1991;98: Robb TM, Mayer DL, Moore BD. Results of early treatment of unilateral congenital cataracts. J Pediatr Ophthalmol Strabismus 1987;24: Fallaha N, Lambert SR. Pediatric cataracts. Ophthalmol Clin North Am 2001;14: Hiles DA. Intraocular lens implantation in children. Ann Ophthalmol 1977;9: Markham RHC, Bloom PA, Chandna A, Newcomb EH. Results of intraocular lens implantation in paediatric aphakia. Eye 1992;6: Sinskey RM, Amin PA, Lingua R. Cataract extraction and intraocular lens implantation in an infant with a monocular congenital cataract. J Cataract Refract Surg 1994;20: BenEzra D, Paez JH. Congenital cataract and IOLs. Am J Ophthalmol 1983;14: Zwaan J, Mullaney PB, Awad A, al-mesfer S, Wheeler DT. Pediatric intraocular lens implantation. Surgical results and complications in more than 300 patients. Ophthalmology 1998;105: Basti S, Ravishankar U, Gupta S. Results of a prospective evaluation of three methods of management of pediatric cataracts. Ophthalmology 1996;103: Lambert SR, Fernandes A, Grossniklaus H, Drews-Botsch C, Eggers H, Boothe RG. Neonatal lensectomy and intraocular lens implantation: effects in rhesus monkeys. Invest Ophthalmol Vis Sci 1995;36: Apple DJ, Solomon KD, Tetz MR, Assia EI, Holland EY, Legler UF, et al. Posterior capsule opacification. Surv Ophthalmol 1992;37: Gimbel HV, DeBroff BM. Posterior capsulorhexis with optic capture: maintaining a clear visual axis after pediatric cataract surgery. J Cataract Refract Surg 1994;20: Koch DD, Kohnen T. Retrospective comparison of techniques to prevent secondary cataract formation after posterior chamber intraocular lens implantation in infants and children. J Cataract Refract Surg 1997;23: BenEzra D, Cohen E. Posterior capsulectomy in pediatric cataract surgery: the necessity of a choice. Ophthalmology. 1997;104: Gimbel HV. Posterior continuous curvilinear capsulorhexis and optic capture of the intraocular lens to prevent secondary opacification in pediatric cataract surgery. J Cataract Refract Surg 1997;23: Wilson ME, Apple DJ, Bluestein EC, Wang XE. Intraocular lenses for pediatric implantation: biomaterials, designs, and sizing. J Cataract Refract Surg 1994;20: Miyake K, Ota I, Miyake S, Maekubo K. Correlation between intraocular lens and hydrophilicity and posterior capsule opacification and aqueous flare. J Cataract Refract Surg 1996;22: Trivedi RH, Wilson ME Jr, Bartholomew LR, Lal G, Peterseim MM. Opacification of the visual axis after cataract surgery and single acrylic intraocular lens implantation in the first year of life. J AAPOS 2004;8: Keech RV, Cibis-Tongue A, Scott WE. Complications after surgery for congenital and infantile cataracts. Am J Ophthalmol 1989;108: Brady KM, Atkinson CS, Kilty LA, Hiles DA. Glaucoma after cataract extraction and posterior chamber lens implantation in children. J Cataract Refract Surg 1997;23: An Eye on the Arts The Arts on the Eye Chance encounters led to magic. Frank Haven Hall, superintendent of the Illinois Institution for the Education of the Blind, unveiled a new device that made plates for printing books in Braille. Previously Hall had invented a machine capable of typing in Braille, the Hall Braille Writer, which he never patented because he felt profit should not sully the cause of serving the blind. As he stood by his newest machine, a blind girl and her escort approached him. Upon learning that Hall was the man who had invented the typewriter she used so often, the girl put her arms around his neck and gave him a huge hug and kiss. Forever afterward, whenever Hall told this story of how he met Helen Keller, tears would fill his eyes. Erik Larson (from The Devil in the White City, Vintage Books)