Measurement of vision function and quality of life in the patients under phacoemulsification with the intraocular lenses of different prices

Abstract

This study was the starting point of the study of the effectiveness in the Phacoemulsification treatment with the intraocular lenses (IOLs) of different prices: IOLs Brand A cost THB 2,000 (USD 44.97) /Lens, IOLs Brand B cost THB 600 (USD 13.49)/Lens and IOLs Brand C cost THB 900 (USD 20.45)/Lens. These were the prices in the year 2001. By the way, all of them basically had the same characteristics : 6 - millimeter diameter, modified C-loop with 1 piece of haptic under the same treatment method which was the mentioned Phacoemulsification. This particular method was one of the most preferable among the opthalmologists for the cataract surgery because of the low rate complication. It was implemented at Lampang Hospital, Ministry of Public Health, Thailand.The objective of the study was to compare the vision function (VF) and the quality of life (QOL), first developed by Fletcher et al, with the scores gained after the surgery by using the 3 brands of polymethyl methacrylate (PMMA) IOLs as well as the risk factors of the complication from the surgery.This study was a cohort study based on the primary data. The cataract patients who were registered for the surgery were selected by the established criteria. Phacoemulsification with intraocular lens implantation was performed by post-graduate opthalmologists who had at least 5 years' experience in the cataract surgery. And those particular selected subjects would be interviewed with the vision function (VF) and quality of life (QOL) questionnaires. In addition to VF and QOL, the other 3 measurements in the thesis were standard gamble (SG), visual analogue scale (VAS) and time trade off (TTO). The analysis consisted of 2 stages. The first stage was the validity test of the tools by partial correlation and regression analysis. From this first stage, it was found that the best tool was QOL. The middle ranks were VF and VAS, and the worst was TTO. The second stage was the means comparing of the scores gained from "before" to "2 weeks after surgery" of vision function and quality of life among the 3 brands of PMMA IOLs by using t-test. As for comparing means, the result showed that the VF scores gained from "before" to "2 weeks after surgery" of IOLs Brand A was significantly more than the ones of IOLs Brand B, and the significance (2-tailed) was .002. And the VF scores gained of IOLs Brand A was significantly more than the ones of IOLs Brand C, and the significance (2- tailed) was .089. This meant that IOLs Brand A had the highest mean of VF scores gained more than IOLs Brand B and IOLs Brand C. This study could be concluded that the intraocular lenses of different brand names ordifferent prices had unequal outcome. Accordingly a further study would be need to seek a cost-effectiveness analysis of cataract surgery to provide the efficiency aspect for decision making.