Abstract
Purpose: :
Reports have shown an increase in the incidence of endophthalmitis after cataract surgery posterior to the introduction of clear corneal incisions. Extraocular fluid inflow through the suturuless incision is probably the mechanism involved in this complication. The purpose of the study was to determine the most favorable sutureless incision architecture to minimize extraocular fluid inflow after cataract surgery.
Methods: :
Seven fresh donor human eyes were used in the study (Tissue Banks International, Baltimore, MD). Two 27-gauge needles connected to a saline solution bag and a digital manometer were inserted through the peripheral cornea 120 degrees from each other. Intraocular pressure (IOP) was maintained at 15 to 20 mm Hg. Three different groups of incisions with a constant width of 2.75 mm were performed in different quadrants of each cornea: A) uniplanar 1.5 mm tunnel length, B) uniplanar 3.0 mm tunnel length, and C) 2-step 3.0 mm tunnel length. A drop of India ink was applied to the surface of the incision, and immediately after IOP fluctuation was induced by applying graded pressure to the limbal area of the opposite quadrant using an ophthalmodynamometer. Digital photography was performed before and after pressure application to measure staining through the wound.
Results: :
The linear distance of India ink inflow after pressure application was higher in groups A and B compared to C (p=0.002, and 0.004 respectively). There was no difference between groups A and B (p=0.937). Additionally, the total area of ink in the tunnel measured in the group C after IOP fluctuation was significantly smaller when compared to A and B groups (p=0.004). No difference in area of ink inflow was found between A and B groups (p=0.589).
Conclusions: :
Intraocular pressure fluctuations may promote extraocular fluid inflow when 1.5 mm and 3.0 mm single-plane incisions are performed. Stepped incisions seem to be more resistant to extraocular fluid inflow in the presence of IOP fluctuation.
Keywords: small incision cataract surgery • cornea: basic science