Quantitative measurement of wound architecture in microincision cataract surgery

To evaluate whether changes in internal wound architecture after phacoemulsification can be measured quantitatively by analysis of scanning electron micrographs.

Baylor College of Medicine, Houston, Texas, USA.

Experimental study.

Two comparative studies in human cadaver eyes were performed using coaxial small-incision cataract surgery (SICS), bimanual microincision cataract surgery (MICS), coaxial MICS, and a variety of phacoemulsification tips (MicroSurgical Technologies, Microphaco Tapered, Microtip Turbosonics, and Microphaco Mackool). After surgery, the cornea and scleral rims were harvested and digital scanning electron micrographs were taken. The internal corneal wound was analyzed using measurement software to determine the area of endothelial cell loss and length of Descemet membrane tears.

Quantifiable differences were observed between combinations of techniques and tip designs. The mean area of endothelial cell loss was 2.93 ± 0.31 mm(2) (SD) after coaxial MICS (n = 4) and 2.85 ± 0.54 mm(2) after bimanual MICS (n = 4). However, after normalizing for differences in tip or sleeve diameter, the area of endothelial cell loss ranged from 1.4-fold to 1.7-fold less with coaxial SICS than with bimanual MICS with Microphaco Tapered, Microtip Turbosonics, and Microphaco Mackool tips. The mean total length of tearing was 1.38 ± 0.38 mm for bimanual MICS (n = 4) and 0.84 ± 0.61 mm for coaxial MICS (n = 4).

The length and area of corneal wounds could be quantitated with accuracy and the measurements could be used to make quantifiable comparisons of phacoemulsification techniques and tips.

Dr. Dimalanta is an employee of Alcon Research, Ltd. No other author has a financial or proprietary interest in any material or method mentioned.