Abstract
Abstract: :
Purpose: The purpose of this study was to quanitfy PCO in the canine patient, to determine if there was a difference in the development of PCO between inherited and diabetic cataracts, and to determine if age, breed, stage of cataract at the time of surgery, or presence of intraocular inflammation berfore and/or after surgery influence PCO development. Methods: One hundred forty–seven dogs (265 eyes) with inherited (121 eyes) or diabetic cataracts (144 eyes) underwent phacoemulsification and PMMA intraocular lens implantation and were prospectively evaluated for the development of PCO at 2 weeks, 6 weeks, 2–4 months, 6 months, and 1 year post–operatively. PCO scores were assigned using a scale of 0–4+ and presence or absence of intraocular inflammation was recorded. Dogs were grouped by age and breed size and a categorical value assigned. The gender and right eye versus left eye were also compared. Statistical analysis was performed using SAS software. Results: No difference in PCO development between diabetic and non–diabetic patients was present at any time interval. The average PCO score 1 year post–operatively was 1.2657 +/– 0.79098 for dogs with inherited cataracts and 1.1818 +/– 0.56580 for dogs with diabetic cataracts. There was no difference in PCO formation between the right and the left eye. A signficant (p<0.0001) increase in PCO formation was observed at each evaluation period in the inherited, diabetic, and the overall population. The age and gender of the animal did not significantly influence PCO formation. Small and medium breeds developed significantly more PCO in comparison to the large/giant breeds at 2 weeks and 2–4 months post–operatively. Eyes with early immature cataracts, up to 4 months post–operatively, had signficantly increased PCO formation. There was no difference in the degree of PCO formation in eyes with inherited cataracts (p=1.53), diabetic cataracts (p=0.593), or the overall population (p=0.238) with or without inflammaton prior to and/or after surgery. Conclusions: PCO formation occurs in all canine patients undergoing phacoemulsification with IOL with 100% incidence 1 year post–operatively. PCO formation is a multifactorial process where age, breed size, and stage of cataract at the time of surgery influence PCO formation. The development of PCO increases over time in diabetic and non–diabetic patients and inflammatory episodes do not contribute to increased PCO formation. Future studies should focus on the development of a new IOL as well as the use of a quantitative method of evaluation.
Keywords: posterior capsular opacification (PCO) • diabetes • cataract