Comparison of macular thickness and inflammatory cytokine levels after microincision versus small incision coaxial cataract surgery

Purpose To compare the macular thickness and volume change, and inflammatory cytokine levels after cataract surgery performed using two different sizes of incision (microincision versus small incision). Methods In this randomized, comparative clinical trial, 84 eyes with nuclear density from Grade 3-4 were randomly divided into two groups (microincision, 2.2 mm; and small incision, 2.75 mm). Forty-two patients underwent phacoemulsification with microincision coaxial cataract surgery and 42 patients underwent phacoemulsification with small incision coaxial cataract surgery. Clinical measurements included preoperative, 1-week, 1-month and 2-month postoperative best corrected visual acuity, central corneal thickness (CCT) and endothelial cell count. ELISA and RT-PCR were performed for IL-1β, IL-6, VEGF and PGE2 preoperatively and at 1 week postoperatively. Results The percentage increase in CCT in the microincision group was significantly higher than that in the small incision group at 1 week after cataract surgery (p = 0.01). The increase in macular thickness in the microincision group was significantly higher than that in small incision group at 1 month after cataract operation (p = 0.04). Also, IL-1β, IL-6, VEGF and PGE2 concentrations and their expression ratio in the microincision group were significantly higher than those in the small incision group at 1 week after cataract surgery compared to the preoperative period (p < 0.05). Conclusions Phacoemulsification with microincision coaxial cataract surgery may increase the macular thickness compared to phacoemulsification with small incision coaxial cataract surgery. Blood-aqueous barrier breakdown may occur more frequently after microincision cataract surgery than after small incision cataract surgery.