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Efficacy and safety of the eight-chop technique in phacoemulsification for patients with cataract
1From the Department of Ophthalmology, Sato Eye Clinic, Chiba-ken, Japan.
Purpose:
The aim of this study was to estimate the efficacy of the 8-chop technique in phacoemulsification surgeries of patients with cataract.
Setting:
Sato Eye Clinic, Chiba-ken, Japan.
Design:
Prospective study.
Methods:
Patients were classified into 3 groups (Grade II, Grade III, and Grade IV; n = 50 each) according to the firmness of their lens nuclei. The Eight-chopper I was used for Grade II, Eight-chopper II for Grade III, and Lance-chopper for Grade IV. The best-corrected visual acuity, intraocular pressure (IOP), and endothelial cell density were evaluated at 7 and 19 weeks postoperatively. The primary outcome measures were the mean operative time, mean phaco time, cumulative dissipated energy (CDE), and volume of fluid used.
Results:
150 cataract surgeries were performed. The operative time (minutes), phaco time (seconds), CDE, and volume of fluid used (milliliters) differed significantly among the 3 groups, increasing in the following order: Grade II, Grade III, and Grade IV ( P < .01). The corneal endothelial cell density did not decrease significantly in the 3 groups at 19 weeks postoperatively ( P = .09). The rate of endothelial cell loss was 0.9% ± 5.9%, 1.0% ± 10.3%, and 5.3% ± 11.1% in the Grade II, III, and IV groups at 19 weeks postoperatively, respectively. There were significant reductions in the IOP at 7 and 19 weeks postoperatively compared with the preoperative IOP in the 3 groups ( P < .01).
Conclusions:
The 8-chop technique was effective and safe in phacoemulsification for patients with cataracts with lens nuclei of varying hardness.

