Objective—To evaluate the outcome of thermokeratoplasty
for treatment of ulcerative keratitis and bullous
keratopathy secondary to corneal endothelial disease
Procedures—Medical records from 1994 to 2001 for
dogs evaluated because of ulcerative keratitis and
bullous keratopathy and treated with thermokeratoplasty
Results—There were 7 spayed females, 5 castrated
males, and 1 sexually intact male, ranging from 6 to
16 years of age. Ten dogs had endothelial degeneration,
and 3 dogs had breed-related endothelial dystrophy.
All dogs had bullous keratopathy, characterized
by microbullae formation that was detected via biomicroscopy.
Recurrent or nonhealing corneal ulcers
were detected unilaterally in 5 dogs and bilaterally in
8 dogs. Mean ± SD duration from thermokeratoplasty
until ulcerations were healed for all dogs was 2.2 ±
1.1 weeks. All dogs that underwent thermokeratoplasty
for nonhealing corneal ulceration secondary to
endothelial disease and corneal edema had epithelial
wound healing and resolution of corneal ulceration.
Mean duration of treatment (ie, topical treatment
required until resolution of ulceration) was significantly
less after thermokeratoplasty than duration of
treatment (with multiple treatments) prior to referral.
Conclusions and Clinical Relevance—It may be
necessary to perform thermokeratoplasty of the
entire cornea to prevent recurrence of ulcerations
in areas that have not been treated with thermokeratoplasty.
(J Am Vet Med Assoc 2003;222:
To calculate the necessary pseudophakic intraocular lens (IOL) power to approximate emmetropia in adult tigers.
17 clinically normal adult tigers.
33 eyes of 17 clinically normal adult tigers underwent routine ophthalmic examination and B-scan ultrasonography while anesthetized for unrelated procedures. Specific ultrasound data (globe measurements and corneal curvature) and estimated postoperative IOL positions were utilized to calculate predicted IOL power by use of Retzlaff and Binkhorst theoretical formulas. Applanation tonometry and refraction were also performed.
Mean ± SD axial globe length was 29.36 ± 0.82 mm, preoperative anterior chamber depth was 7.00 ± 0.74 mm, and crystalline lens thickness was 8.72 ± 0.56 mm. Mean net refractive error (n = 33 eyes) was +0.27 ± 0.30 diopters (D). By use of the Retzlaff formula, mean predicted IOL power for the postoperative anterior chamber depth (PACD), PACD – 2 mm, and PACD + 2 mm was 43.72 ± 4.84 D, 37.62 ± 4.19 D, and 51.57 ± 5.72 D, respectively. By use of the Binkhorst equation, these values were 45.11 ± 4.91 D, 38.84 ± 4.25 D, and 53.18 ± 5.81 D, respectively. Mean intraocular pressure for all eyes was 14.7 ± 2.69 mm Hg.
The calculated tiger IOL was lower than reported values for adult domestic felids. Further studies evaluating actual PACD and pseudophakic refraction would help determine the appropriate IOL power to achieve emmetropia in this species.
Objective—To determine penetration of topically and orally administered voriconazole into ocular tissues and evaluate concentrations of the drug in blood and signs of toxicosis after topical application in horses.
Animals—11 healthy adult horses.
Procedure—Each eye in 6 horses was treated with a single concentration (0.5%, 1.0%, or 3.0%) of a topically administered voriconazole solution every 4 hours for 7 doses. Anterior chamber paracentesis was performed and plasma samples were collected after application of the final dose. Voriconazole concentrations in aqueous humor (AH) and plasma were measured via high-performance liquid chromatography. Five horses received a single orally administered dose of voriconazole (4 mg/kg); anterior chamber paracentesis was performed, and voriconazole concentrations in AH were measured.
Results—Mean ± SD voriconazole concentrations in AH after topical administration of 0.5%, 1.0%, and 3.0% solutions (n = 4 eyes for each concentration) were 1.43 ± 0.37 μg/mL, 2.35 ± 0.78 μg/mL, and 2.40 ± 0.29 μg/mL, respectively. The 1.0% and 3.0% solutions resulted in significantly higher AH concentrations than the 0.5% solution, and only the 3.0% solution induced signs of ocular toxicosis. Voriconazole was detected in the plasma for 1 hour after the final topically administered dose of all solutions. Mean ± SD voriconazole concentration in AH after a single orally administered dose was 0.86 ± 0.22 μg/mL.
Conclusions and Clinical Relevance—Results indicated that voriconazole effectively penetrated the cornea in clinically normal eyes and reached detectable concentrations in the AH after topical administration. The drug also penetrated noninflamed equine eyes after oral administration. Low plasma concentrations of voriconazole were detected after topical administration.