Analysis on tear film after phacoemul sification with different direction of clear cornea incisions with Keratograph 4

Objective To compare the changes in tear film after Microincision coaxial cataract surgery with different direction of clear cornea incisions with Keratograph 4. Methods A clinical case-control study. One hundred and forty-two patients (142 eyes) with age-related cataract were di-vided into two groups according to the surgical approach. Non-invasive tear break time (NIBUT), tear meniscus height, schirmer I test and subjective score for dryness were compared between two groups. Results One day, 7 days and 1 month postoperatively, both the mean NIBUT and tear meniscus height of the clear cornea incision above margin group reduced greatly than the clear corneaincision margin level group. The differences among two groups had significance statistically (Fgroup diff=7577.541, P <0.01; F group diff=9523.241, P <0.01). The values recovered to preoperative levels at 3 months postoperatively and there was no statistically significant difference among the two groups. At 1 day, 7 days, 1 month and 3 months postoperatively, the mean subjective scores for dryness of the a clear cornea incision margin level group were higher than the clear cornea incision above margin group; and a statistically significant difference among the two groups (F group diff=6781.533, P <0.01). All of the values recovered to preoperative levels at 3 months postoperatively. Conclusions A clear cornea incision above margin phacoemulsification bring less disturbance to ocular surface, brighter symptoms of dry eye and the patients feel more comfortable. Key words: Microincision coaxial cataract surgery; A clear cornea incision above margin; A clear cornea incision margin level; Tear film; Dryness