Retinal detachment and glaucoma in the Boston Terrier and Shih Tzu following phacoemulsification (135 patients): 2000-2014.

OBJECTIVES: To report the cumulative incidence of retinal detachment (RD) and glaucoma following phacoemulsification in Boston Terriers and Shih Tzu in the southeastern United States over a 14-year period and investigate the potential predisposing risk factors. METHODS: Medical records of 83 Shih Tzu and 52 Boston Terriers that underwent phacoemulsification between 2000 and 2014, with or without intraocular lens placement, were reviewed. For a comparison population, phacoemulsification data from 45 Labrador Retrievers, 73 Schnauzers, and 159 Bichon Frises were evaluated. Information collected included signalment, concurrent systemic diseases, preoperative findings, surgical details, postoperative complications, and duration of follow-up. Percentages of patients to develop RD and glaucoma were assessed, as well as potential risk factors. Minimum of 3 months of follow-up after surgery was required for inclusion. RESULTS: Retinal detachment occurred in 7.7% (7/91 eyes) and 8.9% (11/123 eyes) and glaucoma occurred in 38.0% (35/91 eyes) and 29.3% (36/123 eyes) of Boston Terriers and Shih Tzu, respectively. Mean follow-up time was 804 days. Neither Boston Terriers nor Shih Tzu were at increased risk for RD or glaucoma when compared to the other breeds, and no significant risk factors for either breed were identified in the final multivariate analysis. CONCLUSIONS: The cumulative incidence of RD in Boston Terrier and Shih Tzu reported here was in agreement with previously reported nonbreed specific percentages (2.7-8.4%). The cumulative incidence of glaucoma in this population of Boston Terriers and Shih Tzu was higher than previously reported nonbreed specific percentages (5.1-18.8%).

Use of a nictitating membrane flap for treatment of feline acute corneal hydrops-21 eyes.

OBJECTIVE: To evaluate the effectiveness of the use of a nictitating membrane flap (NMF) as therapy in 19 cats (21 eyes) affected with feline acute corneal hydrops (FACH). METHODS: Medical records from 19 cats diagnosed with FACH and treated with a NMF were retrospectively evaluated. Information was collected from multiple veterinary hospitals and included signalment, medical history, therapy, and ocular outcome. RESULTS: Breeds included 13 Domestic Shorthairs, 2 Exotic Shorthairs, 2 Maine Coons, 1 Persian, and 1 Domestic Medium Hair. Two cats were bilaterally affected. Median age of cats was 3.2 years (range 0.26-15 years). Eleven patients were spayed females, 6 were neutered males, and 2 were intact males. Topical steroids were previously administered in 5 (23.8%) eyes; oral steroids were previously administered in 7 cats (36.8% of patients); three patients received both oral and topical steroids. Thirteen of 21 (61.9%) eyes had a history of ocular disease including ulcerative and nonulcerative keratitis, anterior uveitis, corneal sequestrum, conjunctivitis, and glaucoma. Median duration of NMF was 15 days (range 6-30 days). Follow-up ranged from 12 to 1601 days (median 169 days). Corneal perforation occurred in 1 (4.7%) eye and was successfully repaired. One lesion (4.7%) in a diabetic patient did not resolve. Nineteen of the treated eyes (90.5%) resolved with no complications. CONCLUSIONS: A nictitating membrane flap successfully treated 90.5% of FACH eyes (89.5% of patients).

Immune-mediated canine and feline keratitis.

Although the normal cornea is devoid of vasculature and lymphatics, there are still several immune-mediated corneal conditions that can occur in dogs and cats. An overview of corneal immunology is presented. Diseases of dogs, including chronic superficial keratitis, superficial punctate keratitis, and canine adenovirus endotheliitis, as well as feline diseases, including eosinophilic keratitis and herpesvirus-related conditions, are discussed.

Inheritance of cataract in the Bichon Frise.

OBJECTIVE: To determine the mode of inheritance of cataract formation in the Bichon Frise. MATERIALS: Thirty-six closely related Bichon Frise dogs in a pedigree of 61 dogs were examined using slit-lamp biomicroscopy and indirect ophthalmoscopy over a period of 10 years. RESULTS: Of the 61 related dogs, 36 were examined repeatedly. Twelve cataractous dogs were diagnosed (three males and nine females). Cataractous dogs resulted from matings between unaffected parents, and when one parent was cataractous and the other parent was unaffected. Age at onset of cataract formation ranged from 18 to 160 months. Available information suggests that the cataracts are inherited as an autosomal recessive trait. CONCLUSION: Cataracts appear inherited in the Bichon Frise as an autosomal recessive trait. Additional cataract x cataract matings are necessary to confirm the autosomal recessive heredity.

Periocular sarcoid in a horse.

A periocular nodular sarcoid of the right upper and lower eyelids was diagnosed in an 11-year-old Thoroughbred mare. Computed tomography scan revealed the extent of the tumor. The mass was surgically debulked under general anesthesia, and the affected periocular region was injected intralesionally with Bacillus of Calmette and Guerin (BCG). An emulsion of cell wall fractions was used, which has been modified to reduce the toxic and allergic effect, but retain the antitumor activity. In total, five injections were performed at 2-week intervals. At follow-up 7 months after the last BCG injection, the tumor was completely resolved. Two years after the last treatment, the horse remains tumor-free.

Hypertensive retinopathy and choroidopathy in a cat.

Bilateral hypertensive retinopathy and choroidopathy with bullous retinal detachment was diagnosed in a 17-year-old, female spayed Domestic Short-haired cat. The underlying cause of the systemic hypertension could not be determined. The blood pressure was lowered successfully with the oral application of the L-type calcium channel blocker amlodipine besylate. The cat subsequently regained vision. The improvement in retinal function was documented using electroretinography.

Detection of anti-lens crystallin antibody in dogs with and without cataracts.

OBJECTIVE: To determine if antilens crystallin (ALC) serum and aqueous humor antibodies were present in normal dogs and dogs with cataracts, whether antibody incidence varied with stage of cataract, and whether antibody titer had a relationship to the presence of lens-induced uveitis. METHODS: Serum and aqueous humor samples were obtained from normal dogs and dogs with cataracts. Lens crystallin was separated by SDS-polyacrylamide gel electrophoresis (SDS-PAGE), and antilens crystallin antibodies were detected by Western immunoblot analysis. An indirect ELISA using crystallin protein as antigen was also used to detect antilens crystallin antibodies in serum and aqueous humor. Test groups included normal, incipient, immature, mature, hypermature and diabetic cataract. RESULTS: SDS-PAGE identified bands with molecular weights of lens crystallin subunits. Western immunoblotting demonstrated reaction between canine serum and these protein bands. The five canine serum samples that reacted with crystallin subunits on Western blots had corresponding reactivity on the ELISA. All aqueous humor samples (30) were negative. Serum ALC antibodies were detected in 59.3% (16/27) of controls, 66.7% (16/24) of incipients, 50.0% (10/20) of immatures, 37.9% (11/29) of matures, 28.6% (6/21) of hypermatures, and 26.7% (4/15) of diabetics. Serum ALC antibodies were detected in 43.1% (47/109) of all cataract samples. There was a statistically significant negative association between the presence (P = 0.004) and maturity (P = 0.004) of cataract and presence of ALC serum antibodies. In the immature and hypermature cataract groups, there was a statistically significant negative association between ALC serum antibody titer and severity of uveitis (95% confidence interval). CONCLUSIONS: There is a negative association between the presence (P = 0.004) and maturity (P = 0.004) of cataract and presence of ALC serum antibodies.

Corneal fungal disease in small animals.

Corneal fungal diseases, including fungal keratitis and stromal abscess, are uncommon in small animals. Ocular infection secondary to systemic mycosis is reported far more frequently. Suspicion of a fungal corneal ulcer should be raised based on a history of underlying trauma, especially with plant material, geographic location, chronic use of topical antibiotics or corticosteroids, or an extremely prolonged course of disease despite appropriate treatment. Clinical signs observed with fungal keratitis may include blepharospasm, epiphora, miosis, corneal opacity, and vascularization. Unfortunately, none of these signs is specific to fungal infection. If fungal keratitis is suspected or confirmed, then aggressive medical therapy should be instituted. Medications used include topical antifungals, parasympatholytics, anticollagenases, and antibacterials as well as systemic anti-inflammatory drugs. Because there are very few fungicidal medications, the course of medical treatment for fungal corneal disease requires a prolonged duration with frequent re-examination and assessment. Surgical treatment is sometimes required to save the eye and vision. Surgeries to be considered include debridement, conjunctival graft placement, and corneal transplantation.

Evaluation of various compounds to inhibit activity of matrix metalloproteinases in the tear film of horses with ulcerative keratitis.

OBJECTIVE: To examine in vitro effects of various antiproteolytic compounds on activity of matrix metalloproteinase (MMP)-2 and -9 in the tear film of horses with active corneal ulcers. SAMPLE POPULATION: Samples of tear film obtained from the eyes of 34 horses with active ulcerative keratitis. PROCEDURE: Horses were sedated, and tear samples were collected from the lower fornix of 34 ulcerated eyes by use of capillary tubes. The protease inhibitors 0.2% EDTA, 0.1% doxycycline, 10% N-acetylcysteine (NAC), 0.1% solution of a modified dipeptide that contains hydroxamic acid (ie, ilomostat), 0.1% alpha1-proteinase inhibitor (PI), 0.5% alpha1-PI, and 100% fresh equine serum (ES) were used to treat pooled samples. Amount of latent and active MMP-2 and -9 was measured by optical density scanning of gelatin zymograms of treated and untreated tear samples. RESULTS: Pooled tear samples obtained from ulcerated eyes contained the latent and active forms of MMP-2 and -9. Compared with MMP activity in untreated samples, total MMP activity (sum of all bands detected) observed on the gelatin zymogram gels was reduced by 99.4% by EDTA, 96.3% by doxycycline, 98.8% by NAC, 98.9% by ilomostat, 52.4% by 0.1% alpha1-PI, 93.6% by 0.5% alpha1-PI, and 90.0% by ES. CONCLUSIONS AND CLINICAL RELEVANCE: We documented that EDTA, doxycycline, NAC, ilomostat, alpha1PI, and ES inhibited MMP activity in vitro. Because these compounds use different mechanisms to inhibit various families of proteases in the tear film of horses, a combination of these protease inhibitors may be beneficial for treatment of corneal ulcers in horses.

Presence of opioid growth factor and its receptor in the normal dog, cat and horse cornea.

OBJECTIVE: To determine if opioid growth factor (OGF, [Met5]enkephalin) and its specific receptor (OGFr) are present in normal cat, dog and horse cornea. ANIMALS STUDIED: Normal dog, cat and horse. PROCEDURE: Corneas were obtained from animals euthanized for reasons unrelated to this project. One cornea from each of three normal cats, dogs and horses was evaluated. The right or left cornea from each animal was chosen randomly. Corneas were harvested and placed in corneal storage media for transport to The M.S. Hershey Medical Center of The Pennsylvania State University where immunocytochemistry techniques were used to demonstrate the presence and location of OGF and OGFr. Tissues were rinsed in Sorenson's phosphate buffer, immersed in 20% sucrose in buffer and then snap frozen in isopentane. Corneas were then embedded in OCT medium and 15 micro m cryostat sections were created. Presence of OGF was determined by using a polyclonal antibody to [Met5]enkephalin and assessing immunoreactivity. OGFr presence was determined by using a previously characterized rabbit polyclonal antibody to the receptor. RESULTS: OGF and OGFr were identified in large quantities in the corneal epithelium of all three species. CONCLUSION: Opioid growth factor and its specific receptor are present in the corneal epithelium of normal cats, dogs and horses. OGF is present in the cornea of many species and its presence is theorized to inhibit healing of injured tissue.

Cataracts in the Bichon Frise.

PURPOSE: To determine the clinical characteristics of possible inherited cataract in the Bichon Frise breed. These characteristics include the relative frequency, gender effects, site of first cataract formation, age of onset, relationship of age to cataract maturity, and other concurrent pre- and postoperative ophthalmic diseases. METHODS: Four different populations of Bichon Frise were examined. They included: (1) referred patients of the University of Florida (VMTH; 1990-2000); (2) patients from other universities and large institutions (VMDB; 1970-2000); (3) patients from the Canine Eye Registry Foundation (CERF; 1970-2000); and (4) special patients recruited from eye clinics and ACVO specialty practices (1995-2001). Blood samples were obtained from many patients for future DNA analyzes. Statistical comparisons between groups were by general linear and anova analyzes, and P < 0.05 was considered significant. RESULTS: The four populations of cataractous and total Bichon Frise dogs included: (1) UF-VMTH: 57 cataractous dogs; (2) VMDB: 406 dogs (28%) with cataracts; total dogs--1407; (3) CERF: 505 cataractous dogs (6%); total dogs--8222; and (4) ACVO: 223 cataractous dogs (57%); total dogs--391. In each population group, gender did not affect cataract distribution. Dogs between 2 and 8 years of age were most frequently affected, and initial cataract involvement affected equally the anterior and posterior cortices. Immature cataracts occurred more often in younger dogs, and hypermature cataracts were more frequently diagnosed in older dogs. Dogs with early cataracts were encountered more frequently in the CERF population. Pre- and postoperative retinal detachments (RD) were not infrequently diagnosed in the UF-VMTH and VMDB groups. RD in the UF-VMTH and VMDB groups occurred in 33% and 13% of the patients, respectively. CONCLUSIONS: Cataracts were first encountered in CERF and VMDB data between 1975 and 1979 and have increased since this time. As expected, both similarities and differences between the four different populations of Bichon Frise were encountered. Both sexes of dogs are equally affected. The anterior and posterior cortical areas of the lens were first involved and dogs 2-8 years of age are most frequently affected. Cataracts affected younger dogs in the CERF group and older cataractous dogs in the other populations. Cataract formation appears to be inherited in the Bichon Frise dog. The frequency of pre- and postoperative retinal detachments present higher risks for cataract surgery in this breed.

Flash electroretinography in standing horses using the DTL microfiber electrode.

PURPOSE: The goal of our study was the evaluation of a practical method for the recording of flash electroretinograms (ERGs) in sedated, standing horses with the DTL microfiber electrode. METHODS: The horses were sedated intravenously with detomidine hydrochloride (0.015 mg/kg). The pupil was dilated and the auriculopalpebral nerve was blocked. The ERGs were recorded with the active electrode on the cornea (DTL), the reference electrode near the lateral canthus, and the ground electrode over the occipital bone. The light intensities of the white strobe light were 0.03 cd x s/m2 (scotopic) and 3 cd x s/m2 (scotopic and photopic). Photopic and scotopic single flash and flicker responses to Ganzfeld stimulation were recorded. During the 20-min dark adaptation period the retina was stimulated every 5 min with the 0.03 cd x s/m2 single flash. RESULTS: The median b-wave amplitudes and implicit times were 38 microV and 33 ms (photopic cone-dominated response), 43 microV and 63 ms (5-min dark adaptation), 72 microV and 89 ms (10 min), 147 microV and 103 ms (15 min), 188 microV and 109 ms (20 min, 0.03 cd x s/m2, rod response), and 186 microV and 77 ms (20 min, 3 cd x s/m2, maximal combined rod-cone response). A steady increase in amplitude and implicit time was noted during dark adaptation. No oscillatory potentials could be isolated. CONCLUSIONS: The use of detomidine hydrochloride sedation and the DTL microfiber electrode allowed the recording of good quality ERGs. This protocol should permit the detection of functional problems in the retina without the risk involved with general anesthesia.

Seasonal effects on the aerobic bacterial and fungal conjunctival flora of normal thoroughbred brood mares in Florida.

OBJECTIVE: To evaluate seasonal effects on the presence or absence of fungal and aerobic bacterial flora of the conjunctival fornix of normal Florida Thoroughbred horses. SAMPLE POPULATION: Both eyes of 100 horses. PROCEDURE: Horses with normal anterior segment ophthalmic examinations from three farms in north central Florida were included. Each animal had the ventral conjunctival fornix of each eye swabbed with sterile culturettes. Samples were taken in October, January, April, and July (1999-2000). Aerobic and fungal cultures were plated. Bacterial cultures were reviewed at 24 and 48 h. Fungal cultures were reviewed weekly for 4 weeks. Logistic regression analysis with season as a factor and age of the horse as a covariate was performed. Statistical significance was set at P < 0.01. RESULTS: Horses ranged from 3 to 24 years of age, with a median age of 9 years. Twenty-four genera of bacteria and 35 genera of fungi were recovered. Corynebacterium sp., Staphylococcus sp., Bacillus sp. and Moraxella sp. were the bacteria most frequently isolated. Mold species, dematiaceous mold species, Chrysosporium sp., Cladosporium sp., and Aspergillus sp. were the most frequently recovered fungi. Season did not have a significant effect on the presence of microorganisms isolated for individual horses adjusted for age. Younger horses had an increased incidence of gram-negative rods and fungal isolates. The number of bacteria and fungi isolated are not uniform across seasons. CONCLUSION: There were no significant differences between the number or type of organisms cultured during the sampling seasons in normal Florida horses. A large range of normal bacterial and fungal flora were isolated from these horses. The number of bacteria and fungi isolated are not uniform across seasons. The likelihood of detecting an organism depends on the horses' age.

Penetrating keratoplasty for treatment of corneal protrusion in a great horned owl (Bubo virginianus).

A young adult great horned owl (Bubo virginianus) was examined following presumed trauma. The owl had soft tissue injury to its left wing as well as corneal protrusion, lens subluxation, and iridodialysis of the right eye. The bird's eye was treated surgically with a large, rectangular penetrating keratoplasty. Following escape from housing, the bird was found with partial wound dehiscence and iris prolapse 12 days post operation. Surgical repair was performed and healing progressed for 14 days, at which time the transplant dehisced and the globe was exenterated. The patient rehabilitated well until escaping from its cage again 4 weeks later, at which time it sustained an open comminuted humeral fracture and was euthanized.

Corneal diseases of rabbits.

Corneal diseases are common in domestic rabbits. It is important to carefully evaluate the cornea and the entire eye when rabbit present with clinical signs such as squinting, tearing, or conjunctival hyperemia. Complete ophthalmic examination and general physical examination should be performed on all rabbits with corneal disease. Important diagnostic testing include culture and sensitivity, cytology, and fluorescein staining. Breed predispositions do not occur for most corneal problems, although some diseases are selected genetically in research rabbits. Corneal disease can be a primary condition or can occur secondary to other ocular or systemic disease.

Density of corneal endothelial cells, corneal thickness, and corneal diameters in normal eyes of llamas and alpacas.

OBJECTIVE: To determine density of corneal endothelial cells, corneal thickness, and corneal diameters in normal eyes of llamas and alpacas. ANIMALS: 36 llamas and 20 alpacas. PROCEDURE: Both eyes were examined in each camelid. Noncontact specular microscopy was used to determine density of corneal endothelial cells. Corneal thickness was measured, using ultrasonographic pachymetry. Vertical and horizontal corneal diameters were measured, using Jameson calipers. RESULTS: Values did not differ significantly between the right and left eyes from the same camelid. There was no significant effect of sex on density of corneal endothelial cells or corneal thickness in either species. Mean density of endothelial cells was 2,669 cells/mm2 in llamas and 2,275 cells/mm2 in alpacas. Density of endothelial cells decreased with age in llamas. Polymegathism was observed frequently in both species. Mean corneal thickness was 608 microm for llamas and 595 microm for alpacas. Corneal thickness and density of endothelial cells were negatively correlated in llamas. Older (> 36 months old) llamas had significantly larger horizontal and vertical corneal diameters than younger llamas, and older alpacas had a significantly larger vertical corneal diameter than younger alpacas. CONCLUSIONS AND CLINICAL RELEVANCE: Density of corneal endothelial cells is only slightly lower in camelids than other domestic species. Density of endothelial cells decreases with age in llamas. Age or sex does not significantly affect corneal thickness in normal eyes of llamas and alpacas. Specular microscopy is useful for determining density of corneal endothelial cells in normal eyes of camelids.

Corneal stromal abscess in a horse.

A thoroughbred yearling presented with a focal, yellow, midstromal corneal opacity with concurrent iridocyclitis which was consistent with a corneal stromal abscess. When continued, appropriate, medical therapy failed to improve the patient's condition, penetrating keratoplasty was performed for diagnosis and therapy. Histopathology showed that the deep corneal stroma and Descemet's membrane were severely infiltrated with necrotic neutrophils and numerous, intralesional fungal hyphae. Culture was negative. Bacteria were not isolated, consistent with a fungal corneal stromal abscess. The resultant corneal scar did not interfere with the horse's racing career.

Treatment of equine glaucoma by transscleral neodymium:yttrium aluminum garnet laser cyclophotocoagulation: a retrospective study of 23 eyes of 16 horses.

Contact neodymium:yttrium aluminum garnet (Nd:YAG) laser transscleral cyclophotocoagulation (TSCP) was performed on 23 eyes of 16 horses for treatment of glaucoma. The mean highest preoperative IOP was 51 +/- 17 mmHg. Follow-up evaluation was available for 19 eyes 1 day after surgery, 14 eyes from 1 to 2 weeks, 16 eyes from 4 to 6 weeks, 9 eyes from 12 to 16 weeks, and 10 eyes greater than 20 weeks after laser treatment. The mean intraocular pressure (IOP) the day following surgery was 34 +/- 13 mmHg. The mean IOP for each follow-up period was: one to two weeks postoperative, 23 +/- 9 mmHg; four to six weeks, 24 +/- 7 mmHg; 12-16 weeks, 28 +/- 10 mmHg; and >/= 20 weeks, 22 +/- 9 mmHg. IOP measurements were significantly different from pretreatment values for all follow-up intervals except for weeks 12-16 (P < 0.05). Treatment success was defined as maintenance of IOP < 30 mmHg. Treatment success was achieved in 93%, 88%, 78%, and 70% of the treated eyes at the 1-2 weeks, 4-6 weeks, 12-16 weeks, and the >/= 20 weeks re-evaluation, respectively. No significant difference was found between the number of eyes visual at presentation (52.2%) and visual at 20 weeks (60%). The most common laser complications were conjunctival hyperemia (21.7%) and corneal ulcers (13.0%). Results of this study indicate that Nd:YAG TSCP is an effective method of controlling IOP and preserving vision in horses with glaucoma. An effective Nd:YAG laser protocol for TSCP in the equine glaucomatous eye is a power setting of 11 W, duration of 0.4 s, applied 5 mm posterior to the limbus at 60 sites, resulting in a total energy dose of 264 J.