Assessment of visual gain following cataract surgeries in Oman: a hospital-based cohort study

ABSTRACT

The post-operative vision is used as benchmark to determine the quality of cataract surgery. However, late presentation and co-morbidities influence the visual gain and they should also be considered while auditing cataract surgeries. The authors present method of analysis of cataract surgeries for older than 30 years of aged patients performed by ophthalmologists in Oman during 2003. Ophthalmologists evaluated visual and ocular status of eyes with cataract. Cataract was operated using operative microscope and lens was implanted in the eye. The vision was recorded six weeks after surgery and visual gain was grouped from postoperative vision in relation to the preoperative vision. Presence of co-morbidities like glaucoma, corneal opacities, macular degenerations and others were considered while evaluating visual outcomes. 3,485 eyes operated were included in our study. 3,003 [86.2%] of them were operated by extra-capsular cataract extraction and lens implantation. Following surgery, 960 [27.5%] eyes had vision >/= 6/18. 1,483 [42.6%] eyes had vision between 6/60 and 6/18. 233 [6.8%] eyes had vision <3/60. Excellent grade of vision gain in relation to preoperative visual status was found in 2,250 [64.6%] eyes, good visual gain was in 422 [12.1%] eyes and poor' visual gain was in 335 [9.6%] eyes. Postoperative visual status was significantly associated to the co-morbidities. [p<0.001]. Nearly 14% of persons were lost to the follow up. In countries like Oman with high prevalence of trachoma, glaucoma and diabetes, the proposed grading of visual gain that accounts for the preoperative vision and the presence of co-morbidity could be better option for auditing the cataract surgery