Long-term follow-up study on prevention of aphakic cystoid macular oedema by topical indomethacin.

In addition to routine medications topical indomethacin was applied to one group of 112 eyes and an appropriate placebo was applied to another group of 106 eyes that underwent intracapsular cataract extraction. The investigation was conducted in a prospective double blind fashion over a long period of time in order to demonstrate the effects of indomethacin in preventing the development of cystoid macular oedema. Indomethacin drops were instilled once a day before surgery, twice on the day of surgery, and 3 times daily for 2 weeks postoperatively. The prevalence of cystoid macular oedema as detected by fluorescein angiograms was as follows: in the early period (from 1 to 2 postoperative months), cystoid macular oedema developed in 250% of the indomethacin-treated eyes and in 51 % of the untreated eyes; in the middle period (from 4 to 7 postoperative months), it developed in 11 0% of the former group and 21 % in the latter group; in the late period (from 1 to 1 5 postoperative years) it developed in 9% of the former group and 11 % of the latter group. In both the early and middle periods the difference in prevalence was statistically significant, but in the late period there was no significant difference between the 2 groups. The onset of 'indomethacin-masked cystoid macular oedema' in several treated eyes may account for the insignificant difference in the late period. Prolonged biosynthesis of indomethacin-sensitive materials, including prostaglandins, may be suspected in some aphakic eyes.