Anterior Elevation Maps as the Screening Test for the Ablation Power of Previous Myopic Refractive Surgery

PURPOSE: We classified the Orbscan anterior elevation maps in normal eyes (under myopic, emmetropic and hyperopic conditions) and in those after myopic refractive surgery. We did this classification to demonstrate how Orbscan anterior elevation maps are useful in screening for the existence and extent of previous myopic refractive surgery. Such a classification can help clinicians interpret preoperative and postoperative topographies. METHODS: We measured for visual acuity and refractive power in 4800 eyes. After a slit-lamp examination, a corneal topography exam was performed with an Orbscan corneal topography system. The eyes were divided into two groups, with Group I representing those who had not had refractive surgery (4438 eyes). Group II included those who had undergone previous refractive surgery to correct myopia (362 eyes). RESULTS: In Group I, the central island type (43.0%) was the most common, followed by the temporal ridge (25.8%), the with-the-rule regular ridge (16.7%), the against-the-rule regular ridge (6.6%), the nasal ridge (4.0%), and the saddle type (2.1%). In Group II, the depressed lake type (69.9%) was most common, followed by the de-centered ablation type (21.3%). The trend line of the postoperative central anterior surface elevation (E) and the ablation power of refractive surgery were calculated. Ablation power of refractive surgery=0.0047 E+0.0083 CONCLUSIONS: This study demonstrates that it is possible to use Orbscan anterior elevation maps to screen for the extent of previous refractory surgery used in the correction of myopia. This study may also be useful in understanding the shapes of Orbscan anterior elevation maps before and after myopic refractive surgery as well as in determining the degree of ablated myopic refractive power and decentration.

The Vision and Satisfaction According to Postoperative Refractive Error after AMO Array(R) Multifocal Intraocular Lens Insertion

PURPOSE: To evaluate the visual outcome and satisfaction according to postoperative refractive error in patient with cataract surgery using AMO Array(R) multifocal intraocular lens. METHODS: According to postoperative refractive errors, 120 eyes (80 patients) were inserted the AMO Array(R) multifocal intraocular lens and were divided into three groups respectively: 28 eyes were myopic group (-0.50 ~ -1.50D), 74 eyes were emetropic group (-0.50 ~ +0.50D) and 18 eyes were hyperopic group (+0.50 ~ +1.50D). In each group, distant vision, near vision and contrast sensitivity test were measured. Also the patients were questioned on their satisfaction. RESULTS: Three months after the operation, the distance uncorrected visions of the myopic, emmetropic and hyperopic group were 0.42 +/- 0.23, 0.73 +/- 0.22, 0.36 +/- 0.28 and the near uncorrected visions were 0.47 +/- 0.18, 0.65 +/- 0.03, 0.41 +/- 0.14 in each. There were no difference in satisfaction, contrast sensitivity and glare visual acuity between three groups. CONCLUSIONS: In cataract surgery using the AMO Array(R) multifocal intraocular lens, we could get the best uncorrected visual acuity in emmetopic group. There were no difference in satisfaction and vision between myopic and hyperopic group. Thus, at the time of cataract operation, the multifocal intraocular lens power should be set on emmetropia in order to improve the vision and satisfaction.

Inhibitory Effects of Mitomycin-C and 5-Fluorouracil on the Proliferation of Lens Epithelial Cells using Capsular Bag Model

PURPOSE: We investigated the inhibitory effects of mitomycin-C (MMC) and 5-fluorouracil (5-FU) on the proliferation of the lens epithelial cells (LECs) depending on time and concentration during the epithelial cell culture using capsular bag model. METHODS: We cultured LECs using capsular bag model after exposure to various time and concentration of MMC and 5-FU. We compared the half coverage time and appearance of posterior capsule by LECs. We examined the proliferative and inhibitory effect on LECs using BrdU immune staining. We observed the morphologic change of LECs on histologic section. RESULTS: Half coverage time of posterior capsule by LEC was 18.2 +/- 3.5 days in control group, whereas 27.5 +/- 3.8 days and 26.8 +/- 4.2 days when treated with 0.2 mg/ml MMC, 50 mg/ml 5-FU for 3 minutes, repectively. The increase of concentration and the exposure time of MMC or 5-FU resulted in the delay of coverage time of posterior capsule by LECs and reduction of BrdU incorporation in the nucleus of proliferating cells. On histologic section, reduction of LECs' multilayering and few cytoplasmic organells were observed. CONCLUSIONS: Using capsular bag model, we found the inhibitory effect of MMC and 5-FU on LECs proliferation depending on the concentration and exposure time. Capsular bag model would be contribute to the study about after-cataract.