The Analysis of Refractive Errors of AMO Array(R) Multifocal Intraocular Lens with SRK II Formula

PURPOSE: To evaluate the accuracy of the SRK II formula for the AMO Array(R) multifocal intraocular lens (Array lens) power calculation according to axial length. In case of refractive error more than +/- 1.0 diopter (D), we compared the accuracy of the SRK II with that of other formulas. METHODS: Participants were 178 eyes (142 patients) received the Array lens. These were divided into 3 subgroups based on axial length. Group I had 21 eyes of short axial length (less than 22.0 mm). Group II had 133 eyes of average axial length (more than 22.0mm below 24.5mm). Group III had 24 eyes of long axial length (more than 24.5mm). The difference between preoperative predicted refractive value and postoperative manifest refractive value were calculated. We compared the accuracy of the SRK II and that of SRK/T, Holladay formulas in case of refractive error more than +/- 1.0D. RESULTS: Three eyes (14.2%) in Group I, 14 eyes (10.5%) in group II and 15 eyes (62.5%) in Group III showed refractive errors more than +/- 1.0D. Fifteen eyes (62.5%) in Group III were significantly reduced to 7 eyes (29.1%) with using SRK/T, Holladay formulas. CONCLUSIONS: SRK II formula had better predictive accuracy in axial length less than 24.5mm with Array lens. But it is better to apply SRK/T or Holladay formulas when axial length is more than 24.5mm.

The Result of Byon's Test in Incomplete Nasolacrimal Duct Obstruction

PURPOSE: To assess the threshold of draining capacity, we performed Byon's test in patients complaining epiphora with incomplete nasolacrimal duct obstruction. METHODS: We measured the draining capacity by using Mclntyre R cannula in 54 patients (98 eyes) from February to December 2000. Through the cannula inserted to lacrimal sac we instilled distilled water for 1 minute at the height of 1.3 meter, then we counted the amount of fluid dropped. RESULTS: The mean values of draining capacity were 2.42+/-0.92 cc/min in men, 2.20+/-0.90 cc/min in women (2.25+/-0.91 cc/min in total). These were lower than normal value by about 48% and the difference was statistically significant (P<0.0001). The highest values in each group were 3.53 cc/min in men, 3.45cc/min in women. Epiphora developed when the draining capacity decreased under the 79% of normal capacity. CONCLUSIONS: This study supports the previous theory that incomplete nasolacrimal duct obstruction may progress to complete obstruction. We hope for another convenient and accurate method for quantitative measurement of lacrimal drainage capacity which will be positioned as a basic test of ophthalmology.

The Clinical outcome of Probing and Silicone Tube Intubation for Congenital Nasolacrimal Duct Obstruction

PURPOSE: We studied the clinical outcome of nasolacrimal probing according to the age and silicone tube intubation for congenital nasolacrimal duct obstruction. METHODS: We analyzed a total of 76 patients (99 eyes) who had undergone nasolacrimal duct probing performed in the office under topical anesthesia and 18 patients (20 eyes) who had undergone silicone tube intubation under general anesthesia between February 1997 and March 2001. Patients who had undergone probing were grouped according to their age at the time of probing: 6 months or less (group 1), 7 to 12 months (group 2) and 13 months or older (group 3). RESULTS: The overall success rate by probing was 84%. The success rate of probing in those under 6 months of age was 88%; in those from age 7 to 12 months, 86%; and in those 13 months or older, the rate decreased to 76%. The decrease in success rate after 13 months was statistically significant (P<0.05). The success rate of silicone tube intubation was 95%. CONCLUSION: We concluded that early office probing under 12 months of age for congenital nasolacrimal duct obstruction is an effective method for treatment of symptomatic nasolacrimal duct obstruction. In case over 13 months of age, probing is also considered as the first choice of treatment although its success rate is lower than the former. Silicone tube intubation is an effective method in case of failure of repeated probing and over 20 months of age.

The Capsular Transplantation in Experimentally Induced Capsule Rupture of Porcine Lens

PURPOSE: We assessed the effect of transplantation of capsule on the change of gross and fine structures of the experimentally induced capsular rupture of porcine lens. METHODS: A rupture of 1.0, 3.0 and 5.0 mm in diameter was made on the anterior capsule of the lens and the anterior capsule was transplanted using lyophilized fibrin adhesive(Greenplast(R)) to cover the rupture. RESULTS: Gross and transmission electron microscopic examinations revealed at day 1, 3 and 7 that the progression of lens opacification was delayed and the stability of microscopic fine structure was less disturbed in the lenses with a rupture of 3.0 mm or less or receiving capsule transplantation less than 4 days after capsule rupture. In the lenses with a rupture of 5 mm or larger or receiving transplantation more than 3 days after capsule rupture, there were no significant differences in gross and microscopic findings between transplantation and control groups CONCLUSION: We applied transplantation concept on the lens. Further studies are needed for transplantation of lens capsule.