David A. Hiles

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 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.

Visual Results after Early Surgical Treatment of Unilateral Con enital Cataracts

The authors reviewed the records of 25 consecutive patients who had been operated on for unilateral congenital cataracts at 1 year of age or younger and who had been followed for a period of 5 years or longer. Excluded were patients who demonstrated retinal and optic nerve anomalies. Five eyes achieved 20/40 or better Snellen visual acuity, 5 eyes achieved 20/50 to 20/100 visual acuity, and 15 eyes had 20/200 or less visual acuity. All patients with visual acuity of 20/40 or better had cataract surgery performed before 17 weeks of age, the critical period, and surgery was scattered within this time frame. For surgery performed between 17 weeks and 1 year of age, the best achieved visual acuity in children with surgically significant unilateral congenital cataracts was between 20/50 and 20/100. There was no correlation between the age at the time of surgery and the attainment of these visual levels in this patient subset.

The Nationwide Study of Epikeratophakia for Aphakia in Children

In the nationwide study of epikeratophakia, 97 surgeons performed a total of 335 procedures in 314 eyes for the correction of aphakia in children under the age of 8 years 1 month. Fifteen children underwent bilateral surgery. Thirty-six tissue lenses were removed and 21 of these eyes underwent a second epikeratophakia procedure. Overall, the success rate for procedures was 89%, and with repeated surgery it was 95% for eyes. Seventy-three percent of the patients were within 3 diopters of emmetropia after surgery. Visual acuity results in patients able to provide verbal responses to the illiterate E, Allen card, or Snellen line chart testing showed improvement in most cases. The safety of epikeratophakia makes it a desirable option for the correction of aphakia in children who are spectacle or contact-lens intolerant, and the permanence of the correction eliminates the problem of optical noncompliance.

The Nationwide Study of Epikeratophakia for Aphakia in Adults

In the nationwide study of epikeratophakia, 154 ophthalmic surgeons who had attended a training course performed 519 procedures for the correction of aphakia in adults: 310 of the eyes had 30 or more days of follow-up after suture removal. Of 229 eyes, 172 (75%) were within 3 diopters of emmetropia after surgery. Of 259 eyes, 245 (95%) demonstrated improved uncorrected visual acuity; 138 (53%) improved by four or more Snellen lines. Of 265 eyes, 209 (78%) achieved within two lines or improved their best corrected visual acuity. Of the 119 patients who achieved or improved their preoperative best corrected visual acuity, 110 (92%) were within two Snellen lines or better by 30 to 60 days after suture removal. Of the 127 patients with more than three months of follow-up after suture removal, 124 (98%) of those between 18 and 70 years of age but only 13 of 23 (54%) of those between 81 and 87 years of age achieved within two lines or better of their best corrected visual acuity. Corneal astigmatism measured by keratometry changed from a preoperative mean (+/- S.D.) of 2.1 +/- 1.8 diopters to a postoperative mean of 2.7 +/- 2.6 diopters. Of the 519 tissue lenses, 22 (4%) were removed, and one third of these patients underwent a second, successful epikeratophakia procedure.

The nationwide study of epikeratophakia for myopia

In the nationwide study of epikeratophakia, 116 ophthalmic surgeons performed 352 procedures for the correction of myopia; 256 of the eyes had 30 or more days of follow-up after suture removal. Of 204 eyes, 153 (75%) were within 30% of emmetropia after surgery. Of 208 eyes, 202 (97%) had postoperative best corrected visual acuity within two Snellen lines or better of their preoperative visual acuity. All but one patient improved uncorrected visual acuity. Of the 120 patients who equaled or improved their preoperative best corrected visual acuity, 116 (97%) were within two Snellen lines of their preoperative measurement between 30 and 60 days after suture removal. Corneal astigmatism changed from a preoperative mean (+/- S.D.) of 1.4 +/- 0.8 diopters to a postoperative mean of 2.6 +/- 2.1 diopters. Of 352 tissue lenses, 36 (10%) were removed, largely as a result of inaccurate power, decay, or failure to reepithelialize, and 17 of these eyes underwent a second successful epikeratophakia procedure.

Modern intraocular lens implants in children with new age limitations

ABSTRACT 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 capsulotornles: 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.

Complications of implant surgery in children.

Rapid recognition and appropriate therapy will prevent or remediate most of the complications occurring in children after cataract aspiration and IOL implantation. Some of the complications of pediatric IOL implantations are related to the increased scleral pliability and decreased rigidity which predispose scleral collapse, vitreous loss, flat anterior chamber and corneal endothelial damage. A second group of complications is associated with the enhanced inflammatory and fibrotic responses peculiar to a childs eye. This group includes operative striate keratitis and iridocyclitis, late IOL precipitates, secondary and postpseudophakos membranes, iris erosion and synechiae formation, and IOL tilt and displacement. Although the intraocular lens is a possible means of visual rehabilitation for children with traumatic cataracts or unilateral infantile cataracts, its long-term risk/benefit ratio must still stand the test of time.

TREATMENT OF SECONDARY POSTERIOR CAPSULAR MEMBRANES WITH THE ND-YAG LASER IN A PEDIATRIC POPULATION

Thirty-two eyes of 28 pediatric patients were treated with the H. S. Meridian Microruptor III Nd:YAG laser for secondary posterior capsular membranes after cataract extraction either with or without posterior chamber intraocular lens implantation. This laser allows for 90-degree rotation of the laser delivery system to treat recumbent patients who may be under general endotracheal anesthesia. In all patients, at least a 5-mm axial capsulotomy was created. The energy requirements for the procedure were related to the density of the membrane, which correlated with the time lapse between cataract extraction and laser capsulotomy. A second laser capsulotomy was performed in eight eyes. Nd:YAG capsulotomy can be performed in a child of any age by using the Microruptor III. For surgeons who choose to retain the posterior capsule in pediatric cataract extraction, particularly after posterior chamber intraocular lens implantation, this technique offers the noninvasive capability to create and maintain a clear visual axis.

Central Corneal Endothelial Cell Counts in Children

Our data indicate that corneal endothelial cell density in a normal eye remains essentially unchanged from ages five to 20. Changes in cell density and morphology during the first five years of life need further investigation. In this study, the mean endothelial cell count of a normal population of children was 2696 cells/mm2. Children undergoing cataract aspiration had a mean cell loss from the normal of 7.2%. The cell loss rates for push-pull aspiration-irrigation or phacoemulsification cataract extraction were not statistically different. The implantation of an intraocular lens was associated with a 33.3% endothelial cell loss when compared to the control or normal population of eyes. A mean loss of 38.0% was noted when the IOL eyes were compared to their normal fellow eyes.