The effect of prophylactic topical carbonic anhydrase inhibitors in canine primary closed-angle glaucoma.
OBJECTIVE
To determine the effect of 1% brinzolamide, 2% dorzolamide hydrochloride or combination 2% dorzolamide hydrochloride/0 · 5% timolol to delay the elevation of the intraocular pressure in second eyes of dogs with primary closed-angle glaucoma.


METHODS
Analysis of retrospectively collated data from 40 dogs with primary closed-angle glaucoma, where the non-affected eye was treated prophylactically with brinzolamide (n = 10), dorzolamide (n = 18) or combination dorzolamide/timolol therapy (n = 12).


RESULTS
The 40 treated dogs (median age of 76 · 2 months) comprised 25 females/15 males, 19 entire/21 neutered. Twenty dogs developed glaucoma in the contralateral eye (median time of 9 · 2 months). No statistically significant difference was identified during treatment failure between the treatment groups (P = 0 · 66). The second eye remained normotensive in 20 dogs; four dogs until the conclusion of the study (median: 27 · 0 months), three dogs until death (median: 15 · 4 months), seven dogs until lost to follow-up (median: 11 · 6 months). Out of these 20 dogs, treatment was discontinued because of lack of owner compliance in two dogs and following a local drug reaction in four dogs (median: 8 · 9 months).


CONCLUSIONS
There was no evidence that the tested drugs delayed elevation of intraocular pressure in contralateral eyes of dogs with primary closed-angle glaucoma.
Comparative Ophthalmology Unit, Animal Health Trust, Lanwades Park, Kentford, Newmarket CB8 7UU.
R
R
Stavinohova
Epidemiology and Disease Surveillance Department, Animal Health Trust, Lanwades Park, Kentford, Newmarket CB8 7UU.
J R
JR
Newton
Comparative Ophthalmology Unit, Animal Health Trust, Lanwades Park, Kentford, Newmarket CB8 7UU.
C
C
Busse
D060433:Administration, Ophthalmic / Q000662:veterinary; D000818:Animals; D002257:Carbonic Anhydrase Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D004283:Dog Diseases / Q000188:drug therapy*; D004285:Dogs; D004359:Drug Therapy, Combination; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000188:drug therapy / Q000662:veterinary*; D007429:Intraocular Pressure / Q000187:drug effects; D008297:Male; D012189:Retrospective Studies; D013449:Sulfonamides / Q000008:administration & dosage / Q000627:therapeutic use*; D013843:Thiazines / Q000008:administration & dosage / Q000627:therapeutic use*; D013876:Thiophenes / Q000008:administration & dosage / Q000627:therapeutic use*; D013999:Timolol / Q000008:administration & dosage / Q000627:therapeutic use*
D002257:Carbonic Anhydrase Inhibitors; D013449:Sulfonamides; D013843:Thiazines; D013876:Thiophenes; D013999:Timolol; C111827:brinzolamide; C062765:dorzolamide