Abstract
Purpose:
To evaluate performance and acceptability of a new compact phacoemulsification system for extracapsular lens extraction during cataract surgery in a rabbit model.
Methods:
Extracapsular lens extraction was performed in 6 New Zealand white rabbits (~12 months old) with grade 2-3 cataracts. Four eyes of 2 rabbits were used to evaluate fluidics (irrigation/aspiration) performance and cutting efficiency of the new phacoemulsification (phaco) system using the Ellips® FX handpiece and WhiteStar® handpiece. Diathermy defined as power required per instrument (pencil and forceps probe) was examined. Eight eyes of 4 rabbits were used to evaluate energy requirement and fluidics performance. Ocular biocompatibility of the new phaco fluidics pack was assessed by slit-lamp biomicroscopy for 4 weeks following surgery and compared to postoperative results obtained in the contralateral eye with a currently marketed compact phaco system and associated fluidics pack.
Results:
Fluidics performance of the new phaco system was acceptable with no surge or bounce at the maximum vacuum range of 200-600 mmHg and flow rate of 20-40 cc/min in Peristaltic pump mode. The new system was more effective in cutting using the Ellips® FX handpiece (score 3.0+0.6) compared to the WhiteStar® handpiece (score 2.1+0.7, p<0.05). For a grade 2 cataract in the rabbit model, the effective phaco time (EPT) was ~1 minute and 11 seconds, and ultrasonic time (UST) was ~32.6 seconds. For a grade 3 cataract, the EPT was ~2 minute and 14 seconds, and the UST was ~2 minutes and 42 seconds. Optimal power setting of the new system was determined to be 20% for cauterizing tissue with pencil probe and between 20-40% using the forceps probe. No post-operative complications and no differences in slit-lamp findings (scores 0-2, p<0.05) were observed in eyes treated with either the new or control phaco fluidics pack.
Conclusions:
Results from this study demonstrated advantages of using the new phaco system with Ellips® FX handpiece and pencil probes for improved phaco power, enhanced fluidics performance and reduced operative duration during extracapsular lens extraction in cataract surgery. EPT and UST were clinically appropriate and acceptable for both grade 2 & 3 cataract in a rabbit model. Unequivocal surgical outcomes also confirmed biocompatibility of the new phaco fluidics pack.