Ulla Kugelberg

Cataract surgery in children with capsulorhexis of anterior and posterior capsules and heparin-surface-modified intraocular lenses

Abstract Cataract surgery was performed in 21 eyes in 14 children (one to 12 years, 5.6 ± 4.0 [mean ± SD]). Cataract surgery was standardized and included capsulorhexis of the anterior capsule, irrigation/aspiration of the nucleus and cortex, puncture of the posterior capsule, injection of sodium hyaluronate (Healon GV®, 14 mg/ml) between the posterior capsule and the vitreous, and capsulorhexis of the posterior capsule. At the end of the procedure, a heparin‐surface‐modified (HSM) poly(methyl methacrylate) intraocular lens (IOL) was implanted in the capsular bag. Follow‐up ranged from four to 16 months. No complications such as the appearance of vitreous in the anterior chamber occurred during surgery. A mild postoperative inflammation was seen in all cases. Opacification of the visual axis was seen in one eye ten months after surgery. Posterior synechial formation was seen in one eye. Our results suggest that capsulorhexis of the anterior and posterior capsules with implantation of an HSM IOL in the capsular bag is a safe procedure in children and produces good postoperative results.

After-cataract formation in newborn rabbits implanted with intraocular lenses

Purpose: Comparison of the after‐cataract formation in newborn rabbits implanted with a heparin‐surface‐modified (HSM) intraocular lens (IOL), a silicone IOL, or no IOL. Methods: Two groups of 3‐week‐old rabbits were used. In Group 1 (n = 11), lensectomy was performed in both eyes. One eye was selected at random and an HSM IOL was implanted in the capsular bag; the other eye was left aphakic. In Group 2 (n = 13), lensectomy was performed in both eyes. An HSM IOL was implanted in one eye, a silicone IOL in the other. The wet mass of the dissected after‐cataract was determined 3 months after surgery in both groups. Results: In Group 1, the wet mass of the dissected after‐cataract was 17.0 ± 6.5 mg (mean ± SEM) in eyes implanted with an HSM IOL and 159.7 ± 17.0 mg in aphakic eyes. This difference was statistically significant (P < .01). In Group 2, the wet mass of the dissected after‐cataract was 18.3 ± 4.3 mg in eyes implanted with an HSM IOL and 25.7 ± 5.2 mg in eyes implanted with a silicone IOL. No statistically significant difference was found. Conclusions: In young rabbits, implantation of an IOL in the capsular bag following lensectomy reduced cell proliferation.

Eye growth in the aphakic newborn rabbit

Purpose: To examine eye growth in unilaterally lensectomized newborn rabbits. Setting: S:t Erik Eye Hospital, Karolinska Institute, Stockholm, Sweden. Methods: Unilateral lensectomy was performed in 18 randomly selected 23‐day‐old rabbits. Corneal incision was performed in 2 other rabbits, and the aqueous humor was replaced with balanced salt solution in one eye. Axial length, corneal diameter, corneal thickness, intraocular pressure (IOP), and refraction were measured in all eyes preoperatively and 1, 2, and 3 months postoperatively. The wet mass of the after‐cataract was measured 3 months after surgery. Results: The growth of the aphakic eye, as indicated by axial length and corneal diameter, was significantly less than that of the control eye in 14 rabbits. No significant difference in IOP or corneal thickness was found between the lensectomy and control eyes. Four animals had elevated IOP with secondary glaucoma and were excluded from the study. No difference in eye growth was found between the two eyes when no lensectomy was performed. Refraction in the unoperated eye showed a myopic shift. After lensectomy, the operated eye became hyperopic with a myopic shift 3 months after surgery. No correlation was found between eye growth and the wet mass of the after‐cataract. Conclusions: Our results suggest that removal of the rabbit crystalline lens at an early age reduces eye growth.

Treatment of anisometropic amblyopia with spectacles or in combination with translucent Bangerter filters.

PURPOSEnTo compare spectacle correction alone with spectacle correction with Bangerter filters to treat anisometropic amblyopia in children.nnnDESIGNnProspective, randomized clinical trial.nnnPARTICIPANTSnEighty children (mean age, 4.4 years) with untreated anisometropic amblyopia and a median best-corrected visual acuity (BCVA) in the amblyopic eye of 0.4 logarithm of the minimum angle of resolution (logMAR).nnnMETHODSnOptimal refractive correction was provided, and the children were assigned to treatment with either spectacles or spectacles in combination with a Bangerter filter worn on the spectacle lens of the better eye. The BCVA, binocular function, and refractive errors were measured repeatedly over the course of 1 year.nnnMAIN OUTCOME MEASURESnThe time course to resolution of the amblyopia (interocular difference, < or =1 line).nnnRESULTSnThe difference in the mean time to the resolution of amblyopia was 3.9+/-3.2 months for the spectacles group versus 2.2+/-1.9 months for the filter group, and the difference reached significance (P<0.05). The BCVA in the amblyopic eye improved significantly (P<0.001 for both comparisons) in both groups. After 1 year, there was no significant difference in the BCVA between the groups. The binocular function improved in both groups; at 1 year there was no significant difference between the groups. The median spherical equivalent refractive error increased significantly during the study in the amblyopic eyes (P<0.05) and the fellow eyes (P<0.001). The median anisometropia decreased significantly from the first visit to the 1-year visit in both groups (P<0.001 for both comparisons).nnnCONCLUSIONSnWe found a more rapid visual acuity recovery with the Bangerter filters than with spectacles alone in eyes with anisometropic amblyopia. However, the 1-year visual acuity outcome was not statistically significantly different between the 2 treatments.

Ocular growth in newborn rabbit eyes implanted with a poly{methyl methacrylate) or silicone intraocular lens

Purpose: To examine eye growth in lensectomized infant rabbits implanted with a poly(methyl methacrylate) (PMMA) or a silicone intraocular lens (IOL). Setting: S:t Eriks Eye Hospital, Karolinska Institute, Stockholm, Sweden. Methods: Two groups of 3‐week‐old rabbits were used. In Group 1 (n = 13), lensectomy was performed in both eyes. In one randomly selected eye, a +30 diopter (D) heparin‐surface‐modified (HSM) PMMA IOL was implanted in the capsular bag; the other eye was left aphakic. In Group 2 (n = 10), a +21 D HSM PMMA IOL was implanted in one randomly selected eye and a +21 D silicone IOL was implanted in the other. Axial length, corneal diameter, corneal thickness, and intraocular pressure (IOP) were measured in all eyes preoperatively and 1, 2, and 3 months after surgery. The wet mass of the after‐cataract was measured 3 months after surgery. The ciliary body with the ciliary processes and the peripheral retina were examined histologically after formalin fixation. The two IOL types were compressed to 7.0 mm, corresponding to the diameter of the 3‐week‐old rabbit lens. Results: In Group 1, the axial length was significantly decreased in the eye with an HSM PMMA IOL compared with the fellow aphakic eye (P < .01, two‐way analysis of variance [ANOVA]). No significant difference in corneal diameter, corneal thickness, or IOP was found between the eyes. The wet mass of the dissected after‐cataract was significantly less in the eye implanted with an IOL. Two animals had an elevated IOP with secondary glaucoma in their aphakic eye and were excluded from the study. In Group 2, axial length in eyes with the HSM PMMA IOL was less than in the eyes with the silicone IOL (P < .25, two‐way ANOVA). No difference in corneal diameter, corneal thickness, or IOP was found. The amount of after‐cataract was not altered. Histologically, the eyes with the HSM PMMA IOL showed retinal degeneration, neovascularization of the ciliary body accompanied by a large number of inflammatory cells, and tumid ciliary processes. The eyes with the silicone IOL showed only minor changes. The aphakic eyes presented even less histological change. The compression test demonstrated that three times the compression force was needed to squeeze the HSM PMMA lens than the silicone IOL. Conclusion: The results suggest that in the young rabbit eye, implanting a regular‐size HSM PMMA IOL destroys intraocular tissues and reduces eye growth significantly. Replacing the PMMA IOL with a silicone IOL improves the ocular growth.

After-cataract and ocular growth in newborn rabbit eyes implanted with a capsule tension ring

Purpose: To examine after‐cataract and eye growth in lensectomized newborn rabbits implanted with capsule tension rings of different sizes. Setting: S:t Eriks Eye Hospital, Karolinska Institute, Stockholm, Sweden. Methods: Two groups of 24‐day‐old rabbits were used. In Group 1 (n = 9), lensectomy was performed in both eyes. In one randomly selected eye, an open poly(methyl methacrylate) (PMMA) capsule tension ring with a 7.0 mm diameter and 0.13 mm thickness was implanted in the capsular bag. The other eye was left aphakic. In Group 2 (n = 10), an open PMMA capsule tension ring with a 10.0 mm diameter and 0.13 mm thickness was implanted in one randomly selected eye, and the other eye was left aphakic. Axial length, corneal diameter, corneal thickness, and intraocular pressure (IOP) were measured in all eyes preoperatively and 1, 2, and 3 months after surgery. The wet mass of the after‐cataract was measured at 3 months. Three Group 1 eyes and four Group 2 eyes developed secondary glaucoma and were excluded from the study. Results: Axial growth did not differ significantly between the eyes implanted with the 7.0 mm ring and the aphakic eyes (mean difference 0.01 mm; F3;15 = 0.02; P>.25). Corneal diameter also did not differ (two‐way analysis of variance [ANOVA]). Axial length growth was less in the eyes implanted with the 10.0 mm ring than in the aphakic eyes (mean difference 1.05 mm; F3;15 = 2.06; P < .25). The average decrease in corneal diameter growth was 1.0 mm in the implanted eyes. Growth in the eyes with the 10.0 mm ring was significantly less than in the eyes with the 7.0 mm ring (P = .05, Wilcoxon rank‐sum test). Corneal thickness and IOP did not differ significantly between eyes (F3;15 = 0.6; P>.25; two‐way ANOVA). Amount of after‐cataract did not differ significantly between the aphakic eyes and the eyes implanted with the 7.0 mm ring. It was significantly less in the eyes with the 10.0 mm ring than in those with the 7.0 mm ring (Wilcoxon signed‐rank test) and in the aphakic eyes (P < .025, Wilcoxon rank‐sum test). Conclusion: In the young rabbit eye, a 10.0 mm capsule ring reduced the eye growth compared with both the aphakic eye and the eye implanted with a 7.0 mm ring. The 10.0 mm ring also inhibited the production of after‐cataract compared with the production in the aphakic eye and the eye implanted with the 7.0 mm ring.

After-cataract evaluation after using balanced salt solution, distilled deionized water, and 5-fluorouracil with a sealed-capsule irrigation device in the eyes of 4-week-old rabbits

PURPOSE: To evaluate the Perfect Capsule sealed‐capsule irrigation device (Milvella Pty., Ltd.) using 3 substances in young rabbit eyes. SETTING: St. Eriks Eye Hospital, Stockholm, Sweden. METHODS: Thirty 4‐week‐old rabbits had clear lens extraction in both eyes. In 1 randomly selected eye, the Perfect Capsule was applied and the lens capsule was irrigated for 5 minutes with 1 of 3 substances: balanced salt solution (BSS), distilled deionized water (DDW), or 5‐fluorouracil (5‐FU) 50 mg/mL. In the other eye, no sealed capsule irrigation was used. Forty days postoperatively, the animals were killed and the eyes fixed in formalin for histologic analysis. After‐cataract was evaluated in 3 ways: clinically, from photographs, and histologically. Central posterior capsule thickness was evaluated using a microscope, camera, and computer. RESULTS: The Perfect Capsule sealed‐capsule irrigation system could be used in all selected eyes. The vacuum to the anterior capsule was tight, and the system was sealed in all eyes. After‐cataract developed in the BSS group and DDW group, but not in the 5‐FU group. The 5‐FU group had significantly less after‐cataract than the other 2 groups (P<.05). There was no difference between the groups in capsule thickness. CONCLUSIONS: The Perfect Capsule sealed‐capsule irrigation system could be used in small eyes. Distilled deionized water did not prevent after‐cataract in rabbit eyes with highly proliferative cells, but 5‐FU was effective in preventing after‐cataract.

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.

Randomized Evaluation of Spectacles Plus Alternate-Day Occlusion to Treat Amblyopia

PURPOSEnTo compare spectacles plus patching >or=8 hours daily 6 days a week with spectacles plus patching >or=8 hours on alternate days to treat amblyopia in children 4 to 5 years of age.nnnDESIGNnProspective, randomized clinical trial.nnnPARTICIPANTSnForty children (median age, 4.3 years) with untreated amblyopia and a median best-corrected visual acuity (BCVA) in the amblyopic eye of 0.9 (range, 0.3-1.5) logarithm of the minimum angle of resolution.nnnMETHODSnRefractive correction was provided, and the children were randomized to patching >or=8 hours daily 6 days a week or patching >or=8 hours on alternate days. The BCVA, binocular function, and refractive errors were measured repeatedly during the study.nnnMAIN OUTCOME MEASUREnMedian change in BCVA of the amblyopic eye after 1 year.nnnRESULTSnThe median change in BCVA of the amblyopic eye did not differ significantly between the 2 groups (0.6 log units for daily occlusion; 0.8 log unit for alternate-day occlusion). The final median BCVA in the amblyopic eyes was 0.1 logarithm of the minimum angle of resolution in both groups. Binocular function improved in both groups with no significant differences between the groups at 1 year. The median spherical equivalent refractive error did not change significantly during the study period in the amblyopic eyes in either group; however, a significant increase was found in the fellow eyes in both groups (daily occlusion, P<0.05; alternate-day occlusion, P<0.001).nnnCONCLUSIONSnThe magnitude of change in the BCVA 1 year after spectacles plus prescribed alternate-day patching was not significantly different than that after spectacles plus prescribed daily patching to treat amblyopia in children 4 to 5 years old. The effect of patching was not separate from that of optical correction with a period of refractive adaptation. Thus, the improvement in visual acuity is a combined effect of spectacle wear and occlusion therapy.

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.