Posterior chamber intraocular lens implants in children: report of a series

The IOLAB, Inc pediatric intraocular lens study. AAPOS Reasearch Committee. American Association for Pediatric Ophthalmology and Strabismus

PURPOSE

This report is a summary of the data of the IOLAB, Inc pediatric intraocular lens (IOL) implantation investigation. The goal of this study was to evaluate the safety and efficacy of IOL implantation for the treatment of pediatric aphakia, pending approval by the Food and Drug Administration.

METHODS

From May 1981 to July 1994, a total of 1260 pediatric eyes received 171 styles of IOLs implanted by 361 US investigators. Preoperative, operative, and postoperative status reports over the first year were required for each eye entered into the study. Annual visit reports were requested thereafter to determine the long-term effects. The study was terminated in November 1995. All IOLs were obtained from IOLAB, Inc (now Chiron Vision Corp).

RESULTS

Reporting compliance was 98.3% for the preoperative and operative reports, 45.1% at 1 year, and 13.8% at 3 years. The subjects' ages ranged from younger than 1 yearto 17 years. Nine subjects (0.7%) were younger than 1 year, with the largest group of 533 subjects (42.3%) aged between 6 and 12 years atthe time of surgery. Cataract types were congenital (45.6%), traumatic (37.1%), secondary (11%), senile (0.95%), and unrecorded (5.4%). The IOL was implanted primarily in 74.8% of cases and secondarily in 21.4% of cases. There was no record in 3.8% of the cases. IOL types included anterior chamber (4.1%), iridocapsular (0.71%), posterior chamber (93.6%), and unrecorded (1.59%). There were 130 adverse reactions that required secondary surgical intervention. The most frequently performed surgical procedures included lens removal without replacement, vitrectomy, lens repositioning, and lens replacement. More than half (52%) of all eyes had a visual acuity of 20/200 or worse before surgery; amblyopia was reported in 21.1% of all participants at baseline. Postoperative visual acuity data were available on 563 eyes at 1 year after surgery. Overall, 52.8% of all eyes attained a visual acuity of 20/40 or better by the 1-year visit, and only 15.5% had visual acuity worse than 20/200. In general, the older patient, traumatic cataract, and secondary cataract categories were overrepresented in the better visual acuity outcome group.

CONCLUSION

The IOLAB, Inc pediatric IOL study is the first multiple-practitioner, national study designed to evaluate the safety and efficacy of IOL implantation in children. The study results are compromised by the almost 50% loss of follow-up at the 1-year evaluation. Other variables that most likely influenced outcome results were the methods of cataract extraction, medical management, and IOL design, all of which evolved dramatically over the time course of the study. Despite these issues, pediatric IOL implantation seems to be a reasonable treatment modality for aphakia, on the basis of the available 1-year follow-up data of the remaining 45.1% of eyes in the study.

Heparin-surface-modified intraocular lenses in pediatric cataract surgery: prospective randomized study

PURPOSE

To evaluate the performance of heparin-surface-modified (HSM) intraocular lenses (IOLs) in pediatric eyes after cataract surgery.

SETTING

L.V. Prasad Eye Institute, Hyderabad, India.

METHODS

This prospective, randomized, double-masked, controlled clinical trial comprised 90 children aged 2 to 14 years with cataract. The patients were consecutively randomized to receive an HSM (Group 1) or an unmodified (Group 2) poly(methyl methacrylate) (PMMA) IOL. Extracapsular cataract extraction (ECCE) with IOL implantation was performed in children 8 years and older and ECCE with primary posterior capsulotomy, anterior vitrectomy, and IOL implantation in children younger than 8 years. Outcome parameters were inflammatory cell deposits on the IOL surface, posterior synechias, and anterior chamber reaction.

RESULTS

Follow-up data were available for 73, 70, 60, and 68 patients at 1 week, 1 month, 3 months, and 6 months, respectively. Significantly fewer cell deposits were noted in Group 1 at 1, 3, and 6 months (P < .001). Synechia formation and anterior chamber reaction were comparable in the 2 groups.

CONCLUSION

The lower incidence of inflammatory cell deposit formation in eyes with HSM PMMA IOLs indicates that these IOLs have greater bicompatibility than unmodified IOLs in pediatric cataract surgery.

Pediatric intraocular lens implantation. Surgical results and complications in more than 300 patients

OBJECTIVE

The study aimed to review pediatric intraocular lens (IOL) implantations performed in the authors' institution for the past 7 years.

STUDY DESIGN

The study design was a retrospective chart review.

PARTICIPANTS

All children who underwent IOL placement between January 1, 1989, and January 31, 1996, at ages 2 to 16 years were studied. Follow-up was a minimum of 6 months up to 4 years with an average of 13 months.

INTERVENTION

Placement of a primary or secondary posterior chamber IOL was performed.

MAIN OUTCOME MEASURES

Visual acuity and possible complications were tabulated.

RESULTS

Fifty-seven percent of the cataracts were caused by trauma, and 37% were infantile cataracts. Visual acuities of 20/40 or better were attained in 44% of eyes and visual acuities of 20/50 to 20/80 were attained in 27% of eyes. Visual acuities were better in children older than 4 years of age (P = 0.001). Compliance with amblyopia therapy improved vision (P = 0.004). Fibrinous membranes occurred in 41 eyes (13%), and posterior capsule opacification occurred in 120 eyes (39%). There were no significant differences in visual outcome and complications between primary and secondary implants (17%) or between capsular bag and sulcus fixation (27%). The first stable postoperative refraction was predicted accurately in most patients, based on the Sanders-Retzlaff-Kraff II (SRK II) formula and intraoperative corneal curvature and axial length determinations. The mean refraction differed from the goal by only +0.28 diopter and 84% were within +/- 2 diopters. A few patients showed large overcorrections or undercorrections. On average, no myopic shift occurred.

CONCLUSIONS

Short-term results of IOLs implanted in children older than 2 years of age were favorable. Visual acuities obtained were better than 20/80 in 71% despite a high prevalence (28%) of penetrating trauma. Major complications were rare.

Outcome and complications of intraocular lenses in children with cataract

PURPOSE

To assess prospectively the complications and changes in refraction, axial length, and keratometry after intraocular lens (IOL) implantation in children with congenital, developmental, and traumatic cataracts.

SETTING

The Children's Hospital, Dublin, Ireland.

METHODS

The study comprised 24 eyes of 20 patients, aged 4 weeks to 12 years, who had extracapsular cataract extraction and posterior chamber IOL implantation. Mean follow-up was 103 weeks (range 34 to 270 weeks).

RESULTS

Six eyes with congenital cataracts operated on between 4 and 28 weeks of age had central, steady, maintained fixation postoperatively. In the developmental cataract group, 64% achieved a visual acuity of 6/24 or better and 43%, 6/12 or better. In the three traumatic cases, visual acuities were 6/6, 6/9, and 6/24. Posterior capsule opacification occurred in 95.8% of eyes and was treated with a neodymium: YAG or Zeigler knife posterior capsulotomy as a secondary procedure. Other postoperative complications (membranous uveitis, iris capture, posterior synechias, iris prolapse) occurred in 29.2% of eyes.

CONCLUSION

With careful management and patient selection, the use of IOLs in children can produce good visual results with a minimum of complications. Further follow-up is needed to assess the long-term visual outcome, complications, and changes in refraction.

Results of a prospective evaluation of three methods of management of pediatric cataracts

BACKGROUND

Although a variety of approaches to manage cataracts in children have been studied, no consensus exists on the optimum approach. The authors, therefore, conducted a prospective, nonrandomized, consecutive study to evaluate three most commonly adopted methods of management of pediatric cataracts.

METHODS

Lensectomy anterior vitrectomy (LAV), extracapsular cataract extraction with intraocular lens implantation (ECCE + IOL) and ECCE, primary posterior capsulotomy, anterior vitrectomy with IOL (ECCE + PPC + AV + IOL) were the surgical procedures performed. Aphakia in the LAV group was corrected with spectacles or contact lenses. Intraoperative and postoperative results were analyzed. Discrete variables among the three groups were compared using chi square test.

RESULTS

One hundred ninety-two eyes were included in the study. There was no statistically significant difference in the intraoperative complications in the three groups. During a mean follow-up period of 11.3 months, postoperative obscuration of the visual axis was seen in 43.7% of eyes in the ECCE + IOL group and in 3.65% of eyes in the ECCE + PC + AV + IOL (p < 0.001). Two of the seven patients in the LAV group in whom contact lenses were prescribed developed corneal infiltrates. Severe postoperative anterior uveitis occurred in 15.9% and 13.8% of eyes in the ECCE + PPC + AV + IOL and ECCE + IOL groups, respectively. None of the eyes that underwent LAV developed this complication (P < 0.001). There was no statistically significant difference in the incidence of retinal detachment, endophthalmitis, or glaucoma in the three groups.

CONCLUSION

Of the three approaches, ECCE + PPC + AV + IOL was conducive to at least short-term maintenance of a clear visual axis, provided optimum refractive correction, and was not associated with increased risk of short-term complications. Continued follow-up of these eyes is necessary to conclude on the long term results of this technique.

Intraocular lens implantation in children in the West Bank and Gaza

In order to evaluate the efficacy and safety of intraocular lens (IOL) implantation in paediatric aphakia, we reviewed the records of a consecutive series of 40 children, under 15 years of age, who had IOLs inserted for congenital and developmental cataracts between September 1990 and December 1992. Visual results and lens-induced complications were evaluated in 67 eyes with a mean follow-up of 27 months (range 12-38 months). In 52 eyes the cataract was removed by limbal lens aspiration and in 15 eyes by pars plicata lens aspiration. One-piece PMMA Sinskey-type posterior chamber implants were used in all cases. Sixty-three eyes had primary and 4 eyes secondary implants. Seventeen (49%) of 35 eyes with congenial cataract and 25 (78%) of 32 eyes with developmental cataract achieved a visual acuity of 6/18 or better. Marked anterior uveitis with pupillary membrane formation occurred in 9 (13%) of the 67 eyes. Visually significant posterior capsule opacification occurred in 5 (28%) of the 18 eyes with intact capsule. Our results demonstrate the suitability of IOL implantation in children from an area of low socioeconomic background, and suggest that IOL implantation is an effective and safe procedure for correction of paediatric aphakia. This may have implications for similar populations.

Cataract surgery and intraocular lens implantation in children

PURPOSE

To evaluate visual outcome and complications after extracapsular cataract extraction with posterior chamber intraocular lens implantation in children.

METHODS

Extracapsular cataract extraction with posterior chamber intraocular lens implantation was performed on 20 eyes of 19 patients with traumatic cataract, ten eyes with unilateral congenital or developmental cataract, and 15 eyes (eight patients) with bilateral developmental cataract. Nd:YAG posterior capsulotomy was performed in the early postoperative period as indicated.

RESULTS

Fourteen (70%) of 20 eyes with traumatic cataract had best-corrected pseudophakic visual acuity of 20/40 or better. When we excluded four eyes with macular injuries from analysis, 14 (87%) of 16 eyes had visual acuity of 20/40 or better. In patients with bilateral cataract in whom vision was quantified by Snellen acuity (nine eyes of five patients), nine of nine eyes had best-corrected pseudophakic visual acuity of 20/40 or better. In the remaining three patients, six of six eyes had central steady and maintained fixation. Visual outcome was poorest in patients with unilateral cataract (ten eyes); one eye had best-corrected pseudophakic visual acuity of 20/40; two eyes, 20/60; two eyes, 20/70; one eye, 20/100; and two eyes, 20/200. One additional eye had central steady maintained fixation and noncentral fixation. Five of ten eyes had four or more lines improvement in visual acuity. Postoperative complications occurred in five eyes, each of which had traumatic cataract. Three eyes developed iris capture, one eye had a postoperative intraocular hemorrhage, and another developed a dense secondary membrane. In 45 postoperative postoperative eyes, 27 (60%) received one Nd:YAG laser posterior capsulotomy. A second Nd:YAG laser posterior capsulotomy was performed in 11 (41%) of these 27 eyes.

CONCLUSIONS

Extracapsular cataract extraction with posterior chamber intraocular lens implantation in children can be accomplished in selected patients, with generally favorable results. However, many of the patients in this series remain potentially amblyogenic, and long-term follow-up may temper our present visual results.

Intraocular lens implantation in infants with congenital cataracts

We evaluated 21 eyes of 13 infants between two and eight months old who had primary posterior chamber intraocular lens (IOL) implantation for congenital cataracts between 1988 and 1993. Twelve eyes had a posterior capsulorhexis or plaque peeling at the time of implantation and one eye had a vitrectomy. Eight eyes had no posterior capsule procedure during the initial surgery. Follow-up ranged from six months to five years. All eyes developed one or multiple posterior synechias and all, except one, required secondary capsulectomy and vitrectomy between one month and one year. Twenty eyes attained stable IOL fixation and a clear visual axis. In one eye, the IOL decentered downward. Patients with bilateral cataracts had greater visual improvement than those with a cataract in one eye only. No patient could manage spectacles postoperatively. Our findings show the benefits of posterior capsulectomy and anterior vitrectomy done in the early postoperative period and that IOL implantation in infants is a reasonable treatment in some parts of the world.

Pseudophakia for traumatic cataracts in children

PURPOSE

The purpose of this prospective study is to evaluate the postoperative visual acuity, refractive error, intraocular pressure, and status of the posterior capsule in children with traumatic cataracts who undergo extracapsular cataract extraction and insertion of a posterior chamber lens.

METHODS

Extracapsular cataract extraction and primary endocapsular fixation of a posterior chamber lens implant were performed in eight children (age range, 4-17 years) with unilateral traumatic cataracts.

RESULTS

There were no intraoperative complications, and seven of eight eyes achieved 20/40 or greater spectacle visual acuity during an average follow-up interval of 10 months (range, 5-20 months). The average postoperative spherical equivalent refractive error was +0.33 diopter (D) (range, -2.25 to +2.12 D); the average postoperative anisometropia was approximately 1 D (range, 0-2.25 D). In one patient, a coagulase-negative staphylococcal endophthalmitis developed 10 days after surgery. In three eyes that had opacified posterior capsules, YAG laser capsulotomy was performed.

CONCLUSIONS

These preliminary results suggest that intraocular lens (IOL) implantation may be a safe and effective method of optical correction for children with traumatic cataracts.

Long-term results of intraocular lens implantation in pediatric patients

Between 1980 and 1990, 42 eyes of 34 patients (age range: 18 months to 18 years) were implanted with an intraocular lens, with 29 being primary implantations and 13 secondary. The primary implantation group comprised patients with congenital, developmental, and traumatic cataracts. Patients in the developmental and traumatic cataract groups achieved the best visual acuity. Those with congenital cataracts had the poorest visual outcome. Follow-up ranged from a minimum of three months to more than ten years. Overall the patients demonstrated an improvement in visual acuity and the psychological advantage of enhanced visual function without spectacles or contact lenses. We conclude that with proper case selection and a controlled, skilled surgical approach, the use of an intraocular lens for visual rehabilitation in the pediatric age group is a feasible approach.

Implantation in children

With the development of posterior chamber lenses and continuous curvilinear capsulorhexis, and with the availability of viscoelastic agents, the use of intraocular lenses (IOLs) in children is becoming more popular. Since 1982, we have implanted posterior chamber IOLs (PC-IOLs) in the capsular bags of 61 cataractous eyes of 46 children and adolescents. The goal was in-the-bag placement facilitated by the use of a small capsulectomy, and, since 1984, by the use of the continuous curvilinear capsulorhexis. Forty-four cataracts were congenital, 13 were traumatic, and 4 were developmental. Cataract extraction with IOL implantation was performed in 16 (26%) preschool cases (ages 2 through 5), in 31 (51%) child cases (ages 6 through 12), and 14 (23%) adolescent cases (ages 13 through 18). Surgical and postoperative complications were minimal. Visual results were good. Fifty-six percent of preschoolers, 87% of children, and 86% of adolescents achieved 20/40 or better best corrected vision, with 79% of the total cohort achieving 20/40 or better. Overall, 35% achieved an uncorrected visual acuity of 20/40 or better. All but two cases had improvement in best corrected vision; if 20/20 was not attained, the cause was mainly due to deprivation amblyopia. Forty-eight percent of patients were within a diopter of emmetropia.

Traumatic cataract surgery with intraocular lens implantation in children

We evaluated our experience of intraocular lens implantation in 22 children with uniocular traumatic cataract. Good visual acuity was achieved in a large proportion of the children despite associated corneal opacities and several intraoperative and postoperative complications. Our study suggests that intraocular lens implantation may have a major role in management of monocular cataracts in children.

Pseudophakia in children: precautions, technique, and feasibility

Intraocular lens implantation in young children can yield satisfactory results when the surgical techniques are modified and adapted to the child's eye. Between June 1983 and July 1988, 84 posterior chamber lenses were implanted in 80 children aged 2 months to 8 years. An elective posterior capsulotomy followed by an anterior vitrectomy was performed in all cases prior to the lens insertion. This step allowed a permanent clear visual axis which in turn has facilitated visual rehabilitation of the pseudophakic eye. The best results occurred in the developmental cataract group followed by the traumatic cataract group; the poorest visual outcome occurred in patients with unilateral congenital cataracts. Amblyopia treatment and alternative methods of correcting pediatric aphakia are discussed.

Intraocular lens implants for uniocular cataracts in childhood

We report the outcome of intraocular lens implantation in 20 children with visually significant cataracts (seven traumatic, 13 non-traumatic). Six patients had anterior and 14 had posterior chamber implants. The mean age of the whole group at the time of surgery was 5.9 years (range 0.3 to 15.1 years), while the mean period of follow-up was 2.4 years (range 0.8 to 5.9 years). Postoperatively 10 patients developed a transient fibrinous uveitis, four required lens repositioning, one needed lens removal, and eight required posterior capsulotomy. Complications warranting secondary surgical procedures occurred predominantly in eyes with posterior chamber implants. Co-operation with conventional amblyopia treatment was satisfactory in eight out of 16 patients. Postoperatively nine out of 18 patients had peripheral fusion, four patients regained visual acuities of better than 6/9, and visual acuity did not improve beyond 3/60 in six cases. In 19 eyes the optical pathway to the retina is clear and the implants are stable with no evidence of persisting inflammation. Contact lenses remain the initial treatment of choice in infancy, but modern intraocular lenses are well tolerated and have a role in the visual rehabilitation of patients with contact lens and probable contact lens failures and older children with uniocular cataracts.

Management of cataracts in children

All children under 19 years of age who are candidates of cataract surgery must be approved by the FDA and have the pediatric protocol approved by the Investigational Review Committee. Twenty-three children who were approved by FDA received 29 Sinskey-style posterior chamber intraocular lenses. Twenty-four were primary and five were secondary posterior chamber implants. Two minor complications could be attributed to the intraocular lens. Five other complications such as an opacifying posterior capsule and one retinal detachment could have occurred in any cataract procedure. The results of this series of lens implantations in children differ from previously reported studies. This difference may be attributed to the selection of the patients (i.e., all over the age of 20 months) and to the surgery technique.

A new technique of congenital cataract surgery with primary posterior chamber intraocular lens implantation

We present a series of nine cases involving primary intraocular lens implantation in congenital cataracts. Because of the problems encountered with the technique used in the earlier cases, we developed a new surgical technique that may be described as primary epilenticular posterior chamber lens implantation followed by pars plana endocapsular lensectomy. This new technique ensures a clear pupillary area, minimizes postoperative complications, and ultimately prevents amblyopia, resulting in useful vision.

Modern intraocular lens implants in children with new age limitations

Seventy-three children received modern designs of posterior and flexible anterior chamber intraocular lenses. Twenty-eight (38%) had anterior chamber and 45 (62%) had posterior chamber lenses implanted. Postoperative implant complications occurred in 38 (54%) eyes; the most frequent was secondary membrane formation. Six eyes (22%) with anterior chamber lenses and 25 eyes (58%) with posterior chamber lenses required posterior capsulotomies. Seventy percent of the posterior chamber lens recipients less than six years of age developed secondary membranes. All of these eyes had a discission except one Nd:YAG laser patient. Forty-eight percent of the patients with posterior chamber lenses over six years of age required posterior capsulotomies: 55% had Nd:YAG laser capsulotomies and 45% had discissions. Based upon these observations, we now recommend primary implantation of flexible anterior chamber lenses in three- to six-year old children who have tissue-free visual axes and for all secondary implantations. Primary posterior chamber lenses are recommended for children six years of age and older and for younger children who will tolerate a Nd:YAG laser capsulotomy.

Intraocular lens implantation in children with monocular cataracts. 1974-1983

Two hundred twenty-five consecutive intraocular lens (IOL) implants performed by the same surgeon from 1977 to 1983 are reviewed. Ninety (40%) patients had traumatic cataracts and 135 (60%) patients had infantile cataracts. Fifty-four percent of the patients presented with preoperative complications. The most frequent were corneal scars (62%) in the traumatic cataract patients, and posterior lenticonus (18%), microphthalmia (16%), PHPV (14%), and optic nerve defects (12%) in the infantile cataract patients. The iris suture lens was implanted from 1973 to 1982, but the posterior chamber lens is now the most frequently implanted primary IOL. Flexible anterior chamber or iris suture IOLs are used as secondary implants. Follow-up ranged from six months to nine years. Postoperatively, 66% of the patients required spectacles for residual optical correction and 55% required occlusion for amblyopia. Postoperative complications consisted of post-pseudophakos membranes (13%), peripheral iris erosion (13%), iris sphincter erosion (18%), dislocated IOLs (7%) and corneal edema (4%). Secondary surgical procedures relating to the IOL were discissions of post-pseudophakos membranes (6 patients), refixation of dislocated lens (15 patients) and IOL removal (6 patients). The best corrected visual acuities during the course of the follow-up was 20/20 to 20/40 in 34% of the patients, 20/50 to 20/100 in 21%, 20/200 in 12%, and less than 20/200 in 33% of patients. Sixty percent of the traumatic cataract patients achieved 20/20 to 20/40 acuity and 17% of the infantile cataract patients achieved this level. Primary implantation patients achieved superior acuities over secondary implantations in both groups.

Complications of intraocular lenses. A historical and histopathological review

Recent improvements in intraocular lens (IOL) design, manufacturing techniques, and surgical techniques have greatly reduced the incidence of complications following implantation, and many authors now consider IOL implantation to be among the most safe and effective major surgical procedures. However, adverse reactions are still seen--some as late sequelae of earlier IOL designs and implantation techniques and some as sequelae of more recent implantations using "state-of-the-art" lenses and surgical techniques. Complications may be due to various factors, including surgical technique, IOL design, or the inability of some eyes with preexisting disease to tolerate an implant. The authors trace the evolution of IOLs since Ridley's first implant, summarizing the modifications in lenses and surgical techniques that were made as complications were recognized. They then review the clinical and histopathological features of selected cases from more than 200 IOLs and/or globes removed due to IOL-related complications and studied in the University of Utah Ocular Pathology Laboratory. It is hoped that this review will provide insights into the pathogenesis of IOL complications, enhancing the current success of implant procedures and stimulating further basic and clinical research in this area.