Comparison of Modified Prechop Technique With a Novel Prechopper With Stop-Chop Technique in 225 Eyes of 149 Dogs With Hard Cataracts Regarding CDE and Postoperative Complications.

Abstract

Objective: To compare cumulative dissipated energy (CDE) and postoperative complications between modified prechop and stop-chop techniques in dogs with hard cataracts.

Animals studied: Seventy-nine dogs with 123 mature cataract eyes were studied for measuring anteroposterior lens diameters, or 149 dogs with 225 hard cataract eyes were treated with prechop phacoemulsification or stop-chop phacoemulsification surgery.

Procedures: A species-specific prechopper (3.5-5.0 mm width) was designed based on canine anteroposterior lens diameter (APLD: 7.40 ± 0.99 mm) and anterior chamber depth (ACD: 2.54 ± 0.75 mm). Among 225 eyes (149 dogs), 110 eyes were randomly selected for prechop phacoemulsification with the specific prechopper, and 115 eyes for stop-chop phacoemulsification. Surgical outcomes, including CDE, postoperative aqueous flare and complications, were evaluated.

Results: The prechop group demonstrated less mean CDE and postoperative aqueous flare incidence compared to the stop-chop group (53.93 ± 15.29 vs. 78.32 ± 21.32, p < 0.001; 35.14% vs. 58.59%, respectively). The prechop group had fewer overall complications than the stop-chop group (35.2% vs. 56.7%). Vision retention rates at final follow-up (30-1440 days postoperation) were comparable (prechop: 95.7% vs. stop-chop: 92.9%), but glaucoma incidence was lower in the prechop group than in the stop-chop cohort (5 vs. 3 eyes). CDE correlated strongly with complication severity.

Conclusions: The prechop technique with a novel prechopper offers a safer, more efficient alternative for phacoemulsification of canine cataracts, particularly in eyes requiring high energy nuclear fragmentation.