Topical Ethylenediaminetetraacetic acid (EDTA) administration following corneal diamond burr keratotomy for calcareous corneal degeneration in canines.

OBJECTIVE

To evaluate the outcomes of canine patients diagnosed with corneal ulceration associated with presumed calcareous corneal degeneration (CCD) that were treated with diamond burr keratotomy (DBK) and ongoing postoperative topical 3% or 4% Ethylenediaminetetraacetic acid (EDTA).

PROCEDURES: Retrospective assessment of CCD cases treated with ongoing topical EDTA following DBK between 2011 and 2020 at Veterinary Ophthalmic Referrals. Descriptive statistics of the study population were assessed, and a survival analysis was performed using R statistical software.

RESULTS

A total of 51 eyes from 41 dogs were assessed, with small terrier breeds overrepresented (27/41, 65.9%). Median age of dogs at the time of diagnosis was 14.3 years (range 8-17.2 years). Following DBK, the median time to commencement of topical EDTA was 11 days (range 0-28 days). Cases were followed for a median duration of 216 days (range 42-1379 days). Corneal ulceration recurred in 7/51 (13.7%) eyes at a median duration of 80 days (range 63-156 days). The probability of recurrence of corneal ulceration associated with CCD at 12 months was 15.6% (95% CI: 4.1-25.7%). A second DBK procedure followed by ongoing topical EDTA was performed in 4/7 (57.1%) of the recurred eyes. These retreated eyes had no further recurrence recorded and a median follow-up time of 401 days (range 120-858 days).

CONCLUSION

Ongoing topical EDTA following DBK is an effective adjunct treatment method for CCD with reduced rates of recurrence of CCD-associated corneal ulceration when compared to published rates of recurrence when treated with DBK alone.