Abstract
Purpose: :
Determine corneal endothelial cell loss (ECL) using bimanual microincision phaco. Correlate cataract classification (LOCS III), total phaco time (PT), average percent phaco power (%PP), and effective phaco time (EPT) with ECL. Correlate LOCS III with PT, %PP, and EPT.
Methods: :
27 surgical eyes (SE) had uncomplicated phaco. 14 previously non–op fellow eyes were non–surgical controls (NSE). Bilateral pre–op and one month post–op specular microscopy, Noncon Robo Model SP–9000 (Konan Medical) was performed to measure endothelial cell density, cells/mm2 (CD). Cataracts graded with LOCS III. Surgery by KLC. With topical and intracameral anesthesia, bimanual microincision phaco (horizontal or vertical chop) was performed, two 1.2mm trapezoidal limbal incisions (Infinity, Alcon). The Duet BiManual System (MicroSurgical Technology) (capsulorhexis forceps (23g), choppers (20g), irrigation and aspiration tips (20g)), and a 0.9mm phaco tip were used. Clariflex or AR40e IOL (AMO) was inserted through a 2.75mm temporal limbal incision, closed with one 10–0 nylon. PT(s) and %PP recorded, (time in foot position three). ECL for SE and NSE calculated (pre–op CD–post–op CD). Proportional loss of cells (PLC) calculated ((ECL/pre–op CD)100). EPT(s) calculated (PTx%PP). Statistics calculated with Wilcoxon signed rank test and Spearman correlation coefficient.
Results: :
Mean post–op SE and NSE, 35d, 32d, respectively. Mean pre–op SE CD: 2119 (656–2890,SD 470.98). Mean pre–op NSE CD: 2233 (1594–2976,SD 434.34). Mean pre–op SE LOCS III: NC 4.03 (2.50–5.90,SD 1.00), NO 3.96 (2.50–5.90,SD 0.91), C 1.49 (0.00–3.40,SD 1.24), P 1.49 (0.00–3.70,SD 1.28). Mean post–op SE CD: 1913 (703–2584,SD 500.56). Mean post–op NSE CD: 2273 (1828–3021,SD 356.40). Mean PT, %PP, and EPT: 30.26 (2.0–68.0,SD 17.87), 8.5 (3.3–13.2,SD 2.88), 2.83 (0.09–8.98,SD 2.26), respectively. Mean SE ECL: 206 (–256–1220,SD 401,p=0.03). Mean SE PLC: 8.52% (–15.39%–53.03%,SD 17.51%,p=0.05). NSE ECL and PLC, no change. No correlations between SE ECL and PLC with LOCS III, PT, %PP, or EPT. LOCS III NC and NO positively correlated with PT (p=0.0001, p=0.0002), %PP (p<0.0001), and EPT (p<0.0001).
Conclusions: :
ECL after bimanual phaco was similar to coaxial phaco. Also, in both techniques cataract density affected the amount of phaco energy used. While ECL after coaxial phaco was associated with increases in cataract density, phaco time, and ultrasound power, ECL after bimanual phaco was not associated with increases in cataract density, phaco time, and ultrasound power. Therefore, bimanual phaco may represent an advancement in surgical technique.