Risk Factors for Cataract Formation after Implantable Collamer Lens Implantation: Over a Mean 7.5-Year Follow-Up Period

PURPOSE: To determine the risk factors and incidence of cataract formation over a long-term mean follow-up of 7.5 years after type V4 implantable collamer lens (ICL) implantation. METHODS: We analyzed the preoperative, 3-month postoperative, 3-year postoperative, and last follow-up data of 228 eyes (118 patients) with mean preoperative spherical equivalent of -12.7 D and minimum postoperative follow-up of 3 years. Additionally, we determined the risk factors for cataract formation and calculated the 10.3 year cumulative cataract formation rate and 10.3 year cumulative cataract surgery rate using a survival curve. RESULTS: After type V4 ICL implantation with minimum follow-up of 3 years, the calculated 10.3 year cumulative cataract formation rate was 20% and actual cataracts developed in 34 eyes (14.9%). The 10.3 year cumulative cataract surgery rate was 12% based on a survival curve and actual cataract surgery was performed in 12 eyes (5.3%). The risk factors for cataract formation were age (odds ratio [OR] = 1.10, p = 0.00), preoperative spherical equivalent (OR = 0.90, p = 0.00), crystalline lens thickness (OR = 9.54, p = 0.00), axial length (OR = 1.33, p = 0.00), 3 months postoperative vault (OR = 0.50, p = 0.03), and existence of peripheral touch between ICL optic margin and crystalline lens at last follow-up (OR = 7.84, p = 0.00). CONCLUSIONS: We suggest one of the main risk factors for cataract formation after ICL implantation is decreased central vault and peripheral touch between ICL optic margin and crystalline lens.

Clinical Characteristics of Exodeviation

PURPOSE: In order to evaluate the incidence and clinical characteristics of exodeviation according to the Kushner's classification. METHODS: We prospectively studied the 820 patients with exodeviation from 1998 to 2003. One hundred thirty patients with systemic abnormalities, eye disease except exodeviation, or histories of previous strabismus operations were excluded. Best-corrected visual acuity, alternate prism cover test or Krimsky test, duction/ versions, funduscopy, and cycloplegic refraction were performed in every patient, and Bielschowsky phenomenon, Worth 4 dot test and Titmus stereotest, in possible patients. We categorized exodeviations according to the Kushner's classification. RESULTS: Of the remaining 690 patients with exodeviation, 318 were male and 372 were female. Age of onset of exodeviation was 3.9 years. Basic exodeviation was most common (76.5%), and followed by tenacious proximal fusion (7.1%), convergence insufficiency (2.8%), proximal convergence (0.6%), pseudo-convergence insufficiency (0.6%) and high AC/A ratio (0.4%). Binocular fusion both at near and at distance was observed in 30% (148 patients) of the patients. The incidence of amblyopia and dissociated vertical deviation was 13.9% and 8.5%, respectively. Bielschowsky phenomenon was observed mostly in patients with early-onset exodeviation. CONCLUSIONS: Basic exodeviation was most commonly observed, followed by tenacious proximal fusion and convergence insufficiency. Patients with exodeviation showed an onset age of 3.9 years and accompanied by an amblyopia and dissociated vertical deviation in 14% and 5%, respectively. One third of the patients showed binocular fusion.

Clinical Findings and Prognosis of Persistent Hyperplastic Primary Vitreous

PURPOSE: To evaluate the clinical findings, visual improvement and preservation of eye according to treatment modality among children with persistent hyperplastic primary vitreous (PHPV) METHODS: A retrospective study, from 1982 to 2001, at Seoul National University Children's Hospital RESULTS: The subjects for investigation were 126 PHPV eyes in 114 children. The mean age at first exam was 3.6 +/- 3.5months, and the mean age at operation was 13.3 +/- 12.1months. Combined type (67%) was most common, followed by posterior (24%), and anterior (9%) types. The chief complaints in order of frequency were are leukocoria (35%), no fixation (23%), strabismus (21%), and microophthalmia (12%). Percentages of eye preservation and visual improvement over 20/1000 were 77%, and 57%, respectively. Nevertheless, the percentage of visual improvement over 20/200 in the anterior type was 25%. CONCLUSIONS: Combined type was most common in PHPV. Clinical findings and treatment modality varieds according to the type. Visual prognosis was poor. However, the post-treatment status was good in view of the treatment purpose. Therefore we can optain a good outcome through active treatment after the exact classification of PHPV eyes and by establishing the treatment purpose.

The Comparison of Clinical Outcome after Ahmed Valve Implantation and Molteno Implantation

PURPOSE: To compare clinical outcome after Ahmed valve implantation and Molteno implantation with tube ligature and releasable internal stent insertion METHODS: The medical records of 56 eyes, which were followed up more than 6 months, after either Ahmed valve implantation (20 eyes, group A) or Molteno implantation (36 eyes, group M) were reviewed retrospectively. Preoperative and postoperative intraocular pressure (IOP) at 1 day, 1 week, and 1, 2 and 6 months and the number of glaucoma medication were measured. Comprehensive success was defined at IOP less than 22 mmHg or when there was a 30 % reduction of preoperative IOP regardless of glaucoma medication. Qualified success was defined at IOP less than 22 mmHg regardless of glaucoma medication. Complete success was defined at IOP less than 22 mmHg without glaucoma medication. RESULTS: There is no statistical significance in postoperative IOP at all the times between groups A and M (p>0.05). Comprehensive success rate between groups A (75.0 %) and M (91.7 %) was not statistically significant (p>0.05). Qualified success rate between groups A (65.0 %) and M (86.1 %) was not statistically significant (p>0.05). Complete success rate between groups A (10.0 %) and M (30.6 %) was not statistically significant (p>0.05). CONCLUSIONS: There was no statistically significant difference in the success rate at postoperative 6 months between Ahmed valve implantation and Molteno implantation with tube ligature and releasable internal stent insertion.