Anna Lundvall

Cataracts in children.

&NA; Bilateral congenital cataract is the most common cause of treatable childhood blindness. Nuclear cataract is usually present at birth and is nonprogressive, whereas lamellar cataract usually develops later and is progressive. Surgery must be performed promptly in cases with dense congenital cataract; if nystagmus has developed, the amblyopia is irreversible. A treatment regimen based on surgery within 2 months of birth combined with prompt optical correction of the aphakia and aggressive occlusion therapy with frequent follow‐up has been successful in unilateral and bilateral cases. Both anterior and posterior capsulorhexes are performed in most children. Intraocular lens implantation can be performed safely in children older than 1 year. Anterior dry vitrectomy is recommended in preschool children to avoid after‐cataract. Opacification of the visual axis is the most common complication of cataract surgery in children. Secondary glaucoma is the most sight‐threatening complication and is common if surgery is performed early. Life‐long follow‐up is essential in these cases.

Sulcus fixation without capsular support in children

PURPOSE To evaluate long-term follow-up in eyes of children who had sulcus fixation of an intraocular lens (IOL) without capsular support. SETTING St. Eriks Eye Hospital/Karolinska Institute, Stockholm, Sweden. METHODS This retrospective study included 21 eyes of 13 children. Seven eyes had Marfans syndrome, 7 essential lens dislocation, 2 perforation with lens injury, and 5 spherophakia. The IOL implantation was primary in 16 eyes and secondary in 5 eyes. Lensectomy was performed with a limbal approach. An IOL with holes in the haptics was sutured in the sulcus, with the knots buried in the scleral bed. RESULTS Mean patient age was 5.8 years +/- 2.6 (SD). Follow-up ranged from 9 to 33 months. No complications occurred during surgery. In all cases after IOL implantation, best corrected visual acuity was equal to or better than preoperatively. After surgery, no opacification of the visual axis, secondary glaucoma, or retinal complication was recorded. Posterior synechia formation occurred in 4 eyes, and 4 had cells on the IOL surface in 2 eyes, the IOL optic subluxated into the anterior chamber with the haptics in place. Both cases were successfully treated with pilocarpine 4%. CONCLUSION Our results suggest that sulcus fixation of an IOL without capsular support is an option to correct aphakia in children.

Cataract extraction and intraocular lens implantation in children with uveitis

AIM To evaluate the long term results of cataract surgery with intraocular lens implantation (IOL) in children with uveitis. METHODS The study included 10 eyes in seven children (age 3.5–10 years, mean 6.5 years). The cataract surgery included capsulorhexis of the anterior and the posterior capsule, anterior vitrectomy in some eyes, and implantation of a heparin surface modified (HSM) poly(methyl methacrylate) (PMMA) IOL into the capsular bag. RESULTS Follow up periods ranged from 1 to 5 years. Best corrected visual acuity after surgery reached 20/50–20/20 in all but two eyes. Opacities or membranes requiring reoperation developed in seven eyes. Glaucoma developed in three eyes after the cataract operation. CONCLUSION These results suggest that implantation of a HSM PMMA IOL is an alternative to correct aphakia also in children with uveitis.

Exfoliation syndrome and extracapsular cataract extraction with implantation of posterior chamber lens

Abstract Extracapsular cataract extraction followed by implantation of a one‐piece posterior chamber polymethylmethacrylate intraocular lens (IOL) into the capsular bag was performed in 25 eyes with exfoliation syndrome and 20 control eyes. The patients were investigated preoperatively and then 1 day, 1 week, 3, 6 and 12 months after surgery. Preoperatively, maximal pupil dilation was significantly smaller in eyes with exfoliation syndrome compared to controls. During surgery the incidence of complications such as ruptures of the zonule or posterior lens capsule, were higher in eyes with exfoliation syndrome. Furthermore, postoperative complications, such as fibrinoid reaction anterior to the IOL followed by posterior synechias and cell deposits, were more common in eyes with exfoliation syndrome compared to control eyes. The results imply that compared to control eyes, eyes with exfoliation syndrome are likely to present more complications both during extracapsular cataract extraction with implantation of intraocular lenses and postoperatively.

Exfoliation syndrome and heparin surface modified intraocular lenses.

Abstract Either heparin surface modified (HSM) or regular polymethyl methacrylate (PMMA) intraocular lenses (IOLs) were implanted after extracapsular cataract extraction in 40 human eyes with exfoliation syndrome in a double‐masked, randomized study. The patients were investigated preoperatively, and then 1 day, 1 week, 3, 6 and 12 months postoperatively. In eyes implanted with the HSM IOL, 26% had a fibrinoid reaction anterior to the IOL, while this complication was found in 50% of eyes implanted with the regular IOL. Pigment and cell deposits were more frequent on the regular IOLs than on the HSM lenses postoperatively. Posterior synechia formation between the iris and the implant or lens capsule was more common in the eyes with regular IOL compared to HSM IOL. No difference in visual acuity between the two groups was found either before or after surgery. The results suggest that in eyes with exfoliation syndrome, a heparin surface modified IOL reduces clinical complications associated with cataract surgery.

Exfoliation syndrome and the effect of phenylephrine and pilocarpine on pupil size

Abstract The horizontal diameter of the pupil was measured on 20 eyes with exfoliation syndrome and 20 control eyes before and after the instillation of 10% phenylephrine and 4% pilocarpine eye drops. Pupil dilation induced by topical application of the alpha, adrenoceptor agonist phenylephrine was significantly smaller in eyes with exfoliation syndrome compared to controls. The cholinergic agonist pilocarpine decreased pupil diameter and this effect was significantly less in cases with exfoliation syndrome. We conclude from these data that the pharmacological response to both adrenergic and cholinergic stimulation is weaker in eyes with exfoliation syndrome compared to controls.

Effect of 3-piece AcrySof and downsized heparin- surface-modified poly(methyl methacrylate) intraocular lenses in infant rabbit eyes

Purpose: To evaluate after‐cataract formation, ocular growth, and intraocular lens (IOL) behavior in lensectomized infant rabbit eyes implanted with a downsized heparin‐surface‐modified poly(methyl methacrylate) (HSM PMMA) IOL with long haptics or a 3‐piece AcrySof® IOL (Alcon Laboratories, Inc.). Setting: St. Eriks Eye Hospital, Stockholm, Sweden. Methods: Clear lens extraction was performed in both eyes of 3‐week‐old rabbits. In Group 1 (n = 9), a downsized HSM PMMA IOL with long haptics was implanted in 1 eye and in Group 2 (n = 9), a 3‐piece AcrySof IOL was implanted in 1 eye. The fellow eyes remained aphakic. Results: The amount of after‐cataract was significantly less in the eyes with the IOLs than in the aphakic eyes. The eyes with the HSM PMMA IOL had significantly less after‐cataract than those with the AcrySof IOL. No significant difference in axial length was noted between the IOL eyes and the aphakic eyes in either group. In the eyes with the 3‐piece AcrySof IOL, there was anterior movement of the optic with occlusion of the pupil. Conclusions: Eyes with the HSM PMMA IOL and the AcrySof IOL had less after‐cataract than the aphakic eyes. The HSM PMMA IOL, however, inhibited after‐cataract production significantly better than the AcrySof IOL. The 3‐piece AcrySof IOL was seriously deformed in the infant rabbit eyes and caused occlusion of the pupil. Surgeons should be cautious in implanting this AcrySof IOL in the eyes of newborns or in eyes with severe microphthalmia.

Evaluation of screening procedures for congenital cataracts

AIM To evaluate the efficacy of two different Swedish screening procedures for early detection of congenital cataracts in comparison with no screening. METHODS Children born between January 1992 and December 1998 in Swedish regions with an established eye-screening routine procedure, diagnosed with congenital cataract, and operated on before 1 y of age, were included in a retrospective study. Age at referral and age at time of the operation were compared between regions using different screening procedures: screening in the maternity wards (Region 1), at the well-baby clinics (Region 2) and one region without any screening (Region 3). RESULTS Seventy-two children were included in the study. Concerning early diagnosis and surgery, Region 1 differed significantly from Regions 2 and 3, which were more similar and were combined for further analysis. The difference in detected cases was greatest at 21 d of age (55% vs 18%; p < 0.001), but persisted even at 100 d of age (78% vs 64%; p < 0.02). Region 1 screening resulted in more and earlier cases detected than the other two regions (22 vs 15 per 100,000 births). In 72% of all cases, surgery was performed in response to referrals from either the maternity wards (36%), or the well-baby clinics (36%). However, half of the cases from the well-baby clinics were detected too late, i.e. at > 100 d. CONCLUSION Eye screening in the maternity ward is preferable to well-baby clinic screening and to no screening at all, since it leads to early detection. Screening should also be performed routinely at well-baby clinics within the period when successful treatment is possible.

Intraocular lens designed for the newborn infant eye

Purpose: To evaluate the effects of an intraocular lens (IOL) designed for small eyes after clear lens extraction in an animal model. Setting: St. Eriks Eye Hospital, Karolinska Institute, Stockholm, Sweden. Methods: Clear lens extraction was performed in both eyes in 19 3‐week‐old rabbits. In 1 randomly selected eye of each rabbit, a small IOL with long haptics was implanted. Axial length, corneal thickness, corneal diameter, and intraocular pressure were measured preoperatively and every month for 6 months postoperatively. Six months after surgery, the wet mass of the after‐cataract was determined. Results: The IOL remained well centered in all eyes. Four animals developed severe glaucoma in 5 eyes (3 aphakic and 2 pseudophakic) soon after surgery and were excluded. In the 15 animals completing the study, signs of glaucoma evolved in 7 animals (5 aphakic and 4 pseudophakic eyes). In aphakic eyes, significant amounts of after‐cataract (median 250 mg) developed in all 15 surviving animals. In pseudophakic eyes, small amounts of after‐cataract (median 30 mg) were present. During the first 2 months after surgery, ocular growth was less in pseudophakic eyes than in aphakic eyes. Conclusions: Results indicate that implantation of a down‐sized IOL with long haptics in small eyes is safe. Considerable less after‐cataract was found in eyes with the IOL than in aphakic control eyes.

After-cataract and secondary glaucoma in the aphakic infant rabbit

Purpose: To study the association between after‐cataract and secondary glaucoma after lensectomy and 5‐fluorouracil treatment in an experimental infant rabbit model. Setting: St Erik Eye Hospital, Karolinska Institute, Stockholm, Sweden. Methods: Lensectomy was performed in both eyes of 16 3‐week‐old rabbits. One randomly selected eye in each rabbit was injected with 2.5 mg of 5‐fluorouracil (5‐FU) at surgery and 5.0 mg the day after surgery to reduce the formation of after‐cataract. Axial length, corneal thickness, corneal diameter, and intraocular pressure were measured preoperatively and 4 times during the 6 months following surgery. Six months after surgery, the wet weight of the after‐cataract was determined. Results: In 16 aphakic eyes treated with 5‐FU, no or a minimal amount (<0.001 g) of after‐cataract developed. None of the eyes showed signs of secondary glaucoma. Of 16 aphakic eyes not treated with 5‐FU, 10 developed considerable amounts of after‐cataract (>0.10 g); 8 of these developed glaucoma. The other 6 eyes had no or minimal after‐cataract and did not develop secondary glaucoma. The relationship between after‐cataract and secondary glaucoma was statistically significant. Conclusion: A significant relationship between the amount of after‐cataract and the development of secondary glaucoma was found in aphakic infant rabbit eyes.