Hayashi K, Nakao F, Hayashi F
Hayashi Eye Hospital, Fukuoka, Japan.
Ophthalmic Surg. 1994 Aug;25(8):510-3.
We studied the extent of corneal endothelial injury after phacoemulsification using the Small-Port Phaco (SPP), a new phacoemulsification instrument that allows linear aspiration during phacoemulsification. Of 72 eyes undergoing phacoemulsification, the SPP was used in 33 (group 1) and a standard phacoemulsification instrument in 39 (group 2). Endothelial cell density was examined by specular microscopy preoperatively and at 1 and 3 months after surgery, and the percentage of endothelial cell loss was evaluated. Operative factors influencing endothelial injury such as the duration of ultrasound emission, the ultrasound power expended, and the amount of irrigating solution used also were measured. The percentages of endothelial cell loss at both 1 and 3 months were significantly less (P < .05) in group 1 than in group 2 (in group 1, 4.3 +/- 3.4% at 1 month, and 5.6 +/- 3.8% at 3 months; in group 2, 6.9 +/- 4.6%, and 8.3 +/- 5.4%, respectively). The duration of emission was shorter and the ultrasound power discharged was smaller in the SPP cases. Since the total ultrasound energy emitted in the SPP cases was less than that in the standard-instrument cases, we conclude that the reduced corneal endothelial damage observed in group 1 was directly related to the smaller total ultrasound power expended in these cases.