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:
Objective—To evaluate the use of an intravitreal sustained-release cyclosporine (CsA) delivery device for treatment of horses with naturally occurring recurrent uveitis.
Animals—16 horses with recurrent uveitis.
Procedures—Horses with frequent recurrent
episodes of uveitis or with disease that was progressing
despite appropriate medication were selected
for this study. Additional inclusion criteria included
adequate retinal function as determined by use of
electroretinography, lack of severe cataract formation,
and no vision-threatening ocular complications (eg,
retinal detachment, severe retinal degeneration, and
posterior synechia). Sustained-release CsA delivery
devices (4 µg of CsA/d) were implanted into the vitreous
through a sclerotomy at the pars plana.
Reexaminations were performed 1, 3, 6, and 12
months after implantation, then continued annually.
Ophthalmic changes, number of recurrent episodes
of uveitis, and vision were recorded.
Results—The rate of recurrent episodes after device
implantation (0.36 episodes/y) was less than prior to
surgery (7.5 episodes/y). In addition, only 3 horses
developed episodes of recurrent uveitis after surgery.
Vision was detected in 14 of 16 affected eyes at a
mean follow-up time of 13.8 months (range, 6 to 24
Conclusions and Clinical Relevance—This intravitreal
sustained-release CsA delivery device may be a
safe and important tool for long-term treatment of
horses with chronic recurrent uveitis. (Am J Vet Res
Objective—To determine the degree of ocular penetration and systemic absorption of commercially available topical ophthalmic solutions of 0.3% ciprofloxacin and 0.5% moxifloxacin following repeated topical ocular administration in ophthalmologically normal horses.
Animals—7 healthy adult horses with clinically normal eyes as evaluated prior to each treatment.
Procedures—6 horses were used for assessment of each antimicrobial, and 1 eye of each horse was treated with topically administered 0.3% ciprofloxacin or 0.5% moxifloxacin (n = 6 eyes/drug) every 4 hours for 7 doses. Anterior chamber paracentesis was performed 1 hour after the final dose was administered, and blood samples were collected at 24 (immediately after the final dose), 24.25, 24.5, and 25 hours (time of aqueous humor [AH] collection). Plasma and AH concentrations of ciprofloxacin or moxifloxacin were determined by use of high-performance liquid chromatography.
Results—Mean ± SD AH concentrations of ciprofloxacin and moxifloxacin were 0.009 ± 0.008 μg/mL and 0.071 ± 0.029 μg/mL, respectively. The AH moxifloxacin concentrations were significantly greater than those of ciprofloxacin. Mean ± SD plasma concentrations of ciprofloxacin were less than the lower limit of quantification. Moxifloxacin was detected in the plasma of all horses at all sample collection times, with a peak value of 0.015 μg/mL at 24 and 24.25 hours, decreasing to < 0.004 μg/mL at 25 hours.
Conclusions and Clinical Relevance—Moxifloxacin was better able to penetrate healthy equine corneas and reach measurable AH concentrations than was ciprofloxacin, suggesting moxifloxacin might be of greater value in the treatment of deep corneal or intraocular bacterial infections caused by susceptible organisms. Topical administration of moxifloxacin also resulted in detectable plasma concentrations.
Objective—To characterize clinical and clinicopathologic
findings, response to treatment, and causes of
systemic hypertension in cats with hypertensive
Animals—69 cats with hypertensive retinopathy.
Procedure—Medical records from cats with systemic
hypertension and hypertensive retinopathy were
Results—Most cats (68.1%) were referred because
of vision loss; retinal detachment, hemorrhage,
edema, and degeneration were common findings.
Cardiac abnormalities were detected in 37 cats, and
neurologic signs were detected in 20 cats.
Hypertension was diagnosed concurrently with chronic
renal failure (n = 22), hyperthyroidism (5), diabetes
mellitus (2), and hyperaldosteronism (1). A clearly
identifiable cause for hypertension was not detected
in 38 cats; 26 of these cats had mild azotemia, and 12
did not have renal abnormalities. Amlodipine
decreased blood pressure in 31 of 32 cats and
improved ocular signs in 18 of 26 cats.
Conclusions and Clinical Relevance—Retinal
lesions, caused predominantly by choroidal injury, are
common in cats with hypertension. Primary hypertension
in cats may be more common than currently
recognized. Hypertension should be considered in
older cats with acute onset of blindness; retinal
edema, hemorrhage, or detachment; cardiac disease;
or neurologic abnormalities. Cats with hypertensioninduced
ocular disease should be evaluated for renal
failure, hyperthyroidism, diabetes mellitus, and cardiac
abnormalities. Blood pressure measurements
and funduscopic evaluations should be performed
routinely in cats at risk for hypertension (preexisting
renal disease, hyperthyroidism, and age > 10 years).
Amlodipine is an effective antihypertensive agent in
cats.(J Am Vet Med Assoc 2000;217:695–702)
Case Description—A 12-year-old castrated male mixed-breed dog was evaluated because of blepharospasm and blindness affecting both eyes.
Clinical Findings—During examination and diagnostic testing of the dog, fine-needle aspirates of splenic nodules were examined microscopically and stage Vb multicentric large-cell lymphosarcoma was identified. Aqueocentesis was performed, and sample analysis revealed intraocular lymphosarcoma; B-cell neoplasia was confirmed by use of a PCR assay for antigen receptor rearrangement (PARR) performed on samples of aqueous humor. Secondary uveitis and glaucoma were detected bilaterally in addition to chronic superficial corneal ulcerations in the left eye.
Treatment and Outcome—Treatment for abdominal and intraocular lymphosarcoma involving administration of vincristine, l-asparaginase, cyclophosphamide, doxorubicin, and prednisone was initiated. Secondary uveitis and glaucoma were controlled with topical treatment; however, the corneal ulceration did not resolve. Seven weeks following diagnosis, the dog died as a result of complications related to systemic neoplasia and chemotherapy.
Clinical Relevance—In the dog of this report, intraocular lymphosarcoma was diagnosed via PARR performed on samples of aqueous humor. Moreover, the immunophenotype of the neoplastic cells was determined by use of that diagnostic technique. Because secondary uveitis is a common finding in dogs and cats with systemic lymphosarcoma, intraocular lymphosarcoma should be considered as a differential diagnosis; furthermore, investigation (eg, PARR performed on aqueous humor samples) to identify the presence of intraocular lymphosarcoma is warranted, thereby allowing targeted interventions to be considered in management of those patients.
OBJECTIVE To compare complications between healthy horses undergoing general anesthesia for ophthalmic versus non-ophthalmic procedures and identify potential risk factors for the development of complications.
DESIGN Retrospective case series.
ANIMALS 502 horses (556 anesthetic procedures).
PROCEDURES Medical records from January 2012 through December 2014 were reviewed to identify horses undergoing general anesthesia. Signalment, body weight, drugs administered, patient positioning, procedure type (ophthalmic, orthopedic, soft tissue, or diagnostic imaging), specific procedure, procedure time, anesthesia time, recovery time, recovery quality, and postoperative complications were recorded.
RESULTS Patients underwent general anesthesia for ophthalmic (n = 106), orthopedic (246), soft tissue (84), diagnostic imaging (110), or combined (10) procedures. Mean procedure, anesthesia, and recovery times were significantly longer for patients undergoing ophthalmic versus non-ophthalmic procedures. Excluding diagnostic imaging procedures, there was a significant positive correlation between surgery time and recovery time. Within ophthalmic procedures, surgery time, anesthesia time, and recovery time were significantly greater for penetrating keratoplasty versus other ophthalmic procedures. There was a significantly higher rate of postoperative colic following penetrating keratoplasty, compared with all other ophthalmic procedures.
CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that in healthy horses, duration of general anesthesia should be minimized to decrease the risk of postanesthetic complications. Judicious use of orally administered fluconazole is recommended for horses undergoing general anesthesia. For horses undergoing a retrobulbar nerve block during general anesthesia, use of the lowest effective volume is suggested.
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.
Objective—To determine appropriate intraocular lens (IOL) implant strength to approximate emmetropia in horses.
Sample Population—16 enucleated globes and 4 adult horses.
Procedures—Lens diameter of 10 enucleated globes was measured. Results were used to determine the appropriate-sized IOL implant for insertion in 6 enucleated globes and 4 eyes of adult horses. Streak retinoscopy and ocular ultrasonography were performed before and after insertion of 30-diopter (D) IOL implants (enucleated globes) and insertion of 25-D IOL implants (adult horses).
Results—In enucleated globes, mean ± SD lens diameter was 20.14 ± 0.75 mm. Preoperative and postoperative refractive state of enucleated globes with 30-D IOL implants was −0.46 ± 1.03 D and −2.47 ± 1.03 D, respectively; preoperative and postoperative difference in refraction was 2.96 ± 0.84 D. Preoperative anterior chamber (AC) depth, crystalline lens thickness (CLT), and axial globe length (AxL) were 712 ± 0.82 mm, 11.32 ± 0.81 mm, and 40.52 ± 1.26 mm, respectively; postoperative AC depth was 10.76 ± 1.16 mm. Mean ratio of preoperative to postoperative AC depth was 0.68. In eyes receiving 25-D IOL implants, preoperative and postoperative mean refractive error was 0.08 ± 0.68 D and −3.94 ± 1.88 D, respectively. Preoperative AC depth, CLT, and AxL were 6.36 ± 0.22 mm, 10.92 ± 1.92 mm, and 38.64 ± 2.59 mm, respectively. Postoperative AC depth was 8.99 ± 1.68 mm. Mean ratio of preoperative to postoperative AC depth was 0.73.
Conclusions and Clinical Relevance—Insertion of 30-D (enucleated globes) and 25-D IOL implants (adult horses) resulted in overcorrection of refractive error.