Double drape tectonic patch with cyanoacrylate glue for surgical repair of corneal defects: 8 cases.

OBJECTIVE: To describe the use of a double drape tectonic patch with cyanoacrylate glue technique for the treatment of deep or penetrating corneal defects in cats and dogs. ANIMALS STUDIED: Eight client-owned animals of which five were cats and three were dogs. PROCEDURE: Eight cases: Four with descemetoceles, three with corneal perforations, and one with a deep stromal ulcer were treated with a double layer of plastic drape material adhered to the cornea with a cyanoacrylate (2-octyl or 2-octyl, N-butyl)-based tissue adhesive. The patch was then covered with a third eyelid flap. RESULTS: Seven of the eight eyes healed uneventfully with a median time to healing time of 20 days (range 14-28 days). After healing, the glue patch had loosened and was removed. One eye of one cat developed bacterial keratitis with an iris prolapse adjacent to the patch and was subsequently enucleated. Only two of the eight eyes had increased corneal neovascularization. CONCLUSION: Treatment of deep or penetrating corneal defects with a double drape tectonic patch and cyanoacrylate glue is a viable option which may be a faster and less expensive alternative to other globe sparing surgical options.

Punctal stenosis in 6 dogs following the long-term use of topical neomycin-polymyxin B-dexamethasone.

Six dogs were diagnosed with punctal stenosis following the long-term use of topical neomycin-polymyxin B-dexamethasone (NPD). All patients were initially presented for ophthalmic diseases requiring ongoing anti-inflammatory therapy. Five of the 6 dogs had previously or concurrently been treated with topical anti-inflammatory medications other than NPD. One patient exclusively received topical NPD prior to the diagnosis of punctal stenosis. The onset of punctal stenosis following therapy with NPD was variable among patients, ranging from 4 months to over 1 year. Diagnosis of punctal stenosis was made based upon the presence of epiphora and visualization of fibrotic tissue over the nasolacrimal puncta.

Canine panuveitis: a retrospective evaluation of 55 cases (2000-2015).

OBJECTIVE: To determine the most common etiologies of panuveitis in a group of dogs, patient response to therapy, and visual outcome. DESIGN: Retrospective study. MATERIALS AND METHODS: Medical records of 55 dogs diagnosed with panuveitis at the Purdue University Veterinary Teaching Hospital between December 2000 and December 2015 were reviewed. Data collected included signalment, season of diagnosis, descriptions of ocular lesions, diagnostic testing, treatment protocols, etiologic diagnoses (when determined), and visual outcome. RESULTS: The most common clinical sign in the anterior segment was aqueous flare and in the posterior segment was serous retinal detachment. The most common diagnosis was idiopathic/immune-mediated disease followed by systemic blastomycosis, lymphoma, and other causes (leptospirosis, aspergillosis, and histoplasmosis). Of the 43 dogs for which follow-up was available, 40% of dogs had resolution of visible inflammation and retinal reattachment, 32% of dogs had slight to moderate improvement, and 28% of dogs had no improvement or deterioration of lesions. Mean follow-up time was 11 months, and mean time to resolution of visible inflammation and retinal reattachment was 32 days. Sixty-five percent of dogs either retained or regained vision in one or both diseased eyes with initial medical therapy. CONCLUSIONS: Idiopathic/immune-mediated panuveitis was the most common diagnosis. Dogs with idiopathic/immune-mediated panuveitis tended to respond more favorably to medical therapy than dogs with infectious panuveitis. Visual outcome was favorable in those dogs that responded to initial medical therapy, but long-term therapy was required in many dogs to maintain vision and prevent recurrence of disease.

Use of an ophthalmic formulation of megestrol acetate for the treatment of eosinophilic keratitis in cats.

OBJECTIVE: To evaluate a compounded ophthalmic formulation of 0.5% megestrol acetate to treat eosinophilic keratitis in cats. STUDY DESIGN: Prospective study. ANIMALS STUDIED: Seventeen client owned cats with eosinophilic keratitis in one or both eyes. METHODS: Eosinophilic keratitis was confirmed by cytology. At each visit, fluorescein staining and photography were performed. Cats were initially treated q 8-12 h with 0.5% megestrol acetate in an aqueous base. Serum glucose was measured at the first or second reexamination. RESULTS: Fifteen of 17 (88%) cats had a positive response to treatment, with 6 of 17 (35%) having complete resolution at the first reexamination (2-4 weeks). Two of 17 (12%) cats did not respond to treatment. Most cats required a treatment frequency of once daily to once weekly to maintain remission of disease. No ocular irritation or systemic side effects were noted in any cat. CONCLUSIONS AND CLINICAL RELEVANCE: The use of an ophthalmic formulation of 0.5% megestrol acetate is a viable option for treating feline eosinophilic keratitis.

Prevalence of methicillin-resistant Staphylococcus spp. in the conjunctival sac of healthy dogs.

OBJECTIVES: To determine the prevalence of selected coagulase-positive methicillin-resistant Staphylococcus aureus (MRS) in the conjunctival sac in a group of healthy dogs and to compare the prevalence of ocular MRS colonization with colonization of typically assessed body sites including the nasal cavity and rectum. ANIMALS STUDIED: 123 healthy dogs were used in the prevalence study: 40 dogs from a shelter and 83 privately owned dogs. PROCEDURES: The sampling procedure included culturing three separate sites per subject in the following order: the lower conjunctival fornices, the nares, and rectum. RESULTS: A low prevalence of 1.6% (2/123) of MRS was detected in healthy dogs. Methicillin-resistant Staphylococcus pseudintermedius was isolated from two dogs, one from a conjunctival swab and the other from a rectal swab. CONCLUSION: The survey data indicate the ocular surface is a potential site of MRS colonization, although the prevalence was low in healthy dogs.

Bartonellosis in cats: a role in uveitis?

Bartonellosis has been widely studied in human and veterinary medicine over the past two decades. Despite this fact, it remains an enigmatic disease in many ways. The causative bacteria, Bartonella spp, are transmitted to cats by fleas and thus the prevalence in cat populations, particularly in temperate climates, is high. Most cats, whether infected naturally or experimentally, remain asymptomatic. Thus, correlating the presence of the organism to clinical disease, including uveitis, in cats has been difficult. This review summarizes what is known of the transmission and pathogenesis of Bartonella spp in cats, the possible role of the organism in feline ocular disease, as well methods of diagnosis and treatment.

Septic lens implantation syndrome in a cat.

A 13-year-old female spayed domestic shorthair cat was presented initially for a change in the appearance of the left eye. On initial examination, a small penetrating wound was suspected as the cause for a corneal scar, an anterior cortical incipient cataract and mild iritis. The cat was not re-presented until 1 year later at which time ocular pain was marked. Severe anterior uveitis and glaucoma were diagnosed and the eye enucleated. Histopathology documented intralenticular coccoid bacteria and septic lens implantation syndrome.

Postoperative complications and visual outcomes of phacoemulsification in 103 dogs (179 eyes): 2006-2008.

OBJECTIVE: To describe the postoperative complications and visual outcome after phacoemulsification in dogs and identify risk factors for complications. ANIMALS STUDIED: One hundred and three dogs (179 eyes) that had phacoemulsification with or without intraocular lens (IOL) placement including foldable acrylic IOLs between March 2006 and March 2008 at Purdue University Veterinary Teaching Hospital. PROCEDURE: Medical records were reviewed and occurrence and dates of postoperative complications were tabulated. Visual status at the final recheck during the study period was recorded. Additional information including signalment, diabetes mellitus status, operative complications and factors, presence of prior lens induced uveitis, preoperative retinopexy, and cataract stage was collected. RESULTS: The majority of eyes were functionally visual (148 eyes, 82.7%) at the end of the study period. Blindness was seen in 18 eyes (10.0%) with reduced vision in 13 eyes (7.3%) at the final recheck. Postoperative ocular hypertension (22.9%), corneal lipid opacity (19.0%), uveitis (16.2%), intraocular hemorrhage (12.3%), retinal detachment (8.4%), and glaucoma (6.7%) were the most common postoperative complications seen in eyes. The odds of blindness were significantly greater (OR = 290.44) in the eyes of Boston terriers compared with mixed breed dogs and with each year of increasing age (OR = 2.00). CONCLUSION: The prognosis for vision after phacoemulsification with injectable IOL placement is good. Boston terriers were at much higher risk for certain complications.

Effect of eyelid manipulation and manual jugular compression on intraocular pressure measurement in dogs.

OBJECTIVE: To determine the effect of eyelid manipulation and manual jugular compression on intraocular pressure (IOP) measurement in clinically normal dogs. DESIGN: Randomized clinical trial. ANIMALS: 30 dogs (57 eyes) without diseases or medications that affect IOP. PROCEDURES: An applanation tonometer was used to measure IOP during eyelid manipulation or jugular compression. Six manipulations were used in each eye, including minimal eyelid manipulation, maximal dorsoventral extension of the eyelids, lateral eyelid extension, manual compression of the ipsilateral jugular vein, manual compression of both jugular veins, and lateral eyelid extension with manual compression of both jugular veins. Skull type and position of globe in the orbit were recorded. RESULTS: The 2 manipulations that caused the greatest significant increase in mean IOP were lateral eyelid extension with compression of both jugular veins (difference from baseline IOP, 17.6 mm Hg; 95% confidence interval [CI], 15.7 to 19.5 mm Hg) and lateral eyelid extension alone (16.5 mm Hg; 95% CI, 14.6 to 18.4 mm Hg). Dorsoventral eyelid extension (6.42 mm Hg; 95% CI, 4.5 to 8.3 mm Hg) and compression of both jugular veins alone (3.0 mm Hg; 95% CI, 1.1 to 5.0 mm Hg) significantly increased mean IOP, compared with baseline. Compression of the ipsilateral jugular vein increased mean IOP (0.3 mm Hg; 95% CI, -1.6 to 2.2 mm Hg) from baseline, but not significantly. CONCLUSIONS AND CLINICAL RELEVANCE: Traction on the eyelids or pressure on both jugular veins can significantly increase IOP values as measured by use of applanation tonometry in clinically normal dogs.

Stability of 0.5% cidofovir stored under various conditions for up to 6 months.

OBJECTIVE: To evaluate the effect of time, temperature and storage vial material on the antiviral activity of 0.5% cidofovir solution. PROCEDURES: Commercial 7.5% cidofovir solution for injection was diluted with normal saline to a 0.5% concentration. Aliquots were stored in plastic and glass vials at 4, -20, and -80 degrees C for 30, 60, 120, and 180 days. Antiviral activity against feline herpesvirus was evaluated in a virus titration assay at time zero (baseline) and at each subsequent time point. RESULTS: Cidofovir caused a fourfold log reduction in virus titer at baseline and at each time point and for each storage condition (P < 0.001). CONCLUSION: 0.5% cidofovir demonstrated stable antiviral activity when stored for up to 6 months in glass or plastic, at 4, -20, and -80 degrees C.

Coccidioides posadasii keratouveitis in a llama (Lama glama).

A 7-year-old male llama was examined for a 3-month history of weight loss, and unilateral keratouveitis. Clinical examination revealed nonulcerative corneal stromal abscessation, corneal vascularization, corneal edema, miosis, posterior synechia, cataract, and fibrin in the anterior chamber of the right eye. The left eye was normal. Histopathology of the right eye following enucleation revealed pyogranulomatous keratouveitis with intralesional fungal spherules consistent with Coccidioides spp. PCR amplification with DNA sequencing confirmed Coccidioides posadasii infection. To the authors' knowledge, this is the first reported case of ocular coccidioidomycosis in a llama.

Effects of lambda-carrageenan on in vitro replication of feline herpesvirus and on experimentally induced herpetic conjunctivitis in cats.

PURPOSE: To evaluate the inhibitory effect of lambda-carrageenan type IV on feline herpesvirus (FHV)-1 in an in vitro model and in experimentally induced conjunctivitis in vaccinated cats. METHODS: Standard plaque reduction assay, virus titration, and quantitative polymerase chain reaction (qPCR) were used to assess the effect of carrageenan on FHV-1 in vitro. Eighteen adult specific pathogen-free cats, vaccinated against FHV-1 several months earlier, were used to determine the ocular irritative effects of carrageenan, followed by the effect on FHV-1-induced conjunctivitis. Ocular examinations, virus isolation, and partial thromboplastin time (PTT) were evaluated during the study period. RESULTS: When added before virus adsorption, the 50% inhibitory concentration (IC50) of carrageenan was 5 microg/mL, and the 90% inhibitory concentration (IC90) was 25 microg/mL. When added after virus adsorption, there was no inhibitory effect on plaque formation at any concentration. There was no effect of carrageenan on virus titer. Virus copy numbers assessed by quantitative PCR were significantly but marginally reduced when carrageenan was added before and after virus adsorption. Topical application of carrageenan at 250 microg/mL in cats with FHV-1-induced conjunctivitis resulted in a significant reduction in positive virus isolation samples on day 21 of the study but did not alter clinical signs of disease. There was no adverse effect on PTT values. CONCLUSIONS: lambda-Carrageenan type IV blocked FHV-1 adsorption in the plaque assay. Carrageenan shortened the time period in which infected cats had positive virus isolation from the conjunctiva but did not alter the clinical course of FHV-1 conjunctivitis in cats.

Detection of virulent feline herpesvirus-1 in the corneas of clinically normal cats.

To evaluate the clinically normal feline cornea for the presence of virulent feline herpesvirus-1 (FHV-1), corneas from 31 cats (25 with normal eyes and six with active disease or corneal scarring) euthanased at a shelter were collected. Corneas from two specific pathogen-free cats were included as negative controls. Virus isolation (VI), fluorescent antibody (FA) staining and real-time polymerase chain reaction (rt-PCR) were performed on all samples. The presence or absence of dexamethasone in the media was evaluated for its effect on VI. VI was positive for FHV-1 in six corneas from five cats, all with clinically normal eyes. One cornea was positive for feline calicivirus (FCV) in addition to FHV-1, but only in media that included dexamethasone. Eight corneas were positive on rt-PCR for FHV-1, all from cats with clinically normal eyes. All positive VI samples were confirmed with FA staining. VI and rt-PCR were negative for FHV-1 and FCV in cats with active disease or corneal scarring. Data from this study indicate that virulent FHV-1 and FCV can be present in feline corneas that are clinically normal. Dexamethasone may enhance viral spread through a cell receptor mechanism.

Heterologous penetrating keratoplasty for treatment of a corneal sequestrum in a cat.

A corneal sequestrum was diagnosed in an 8-year-old, neutered male Burmese cat. A heterologous penetrating keratoplasty (PK) (fresh canine corneal tissue) was performed to restore a clear visual axis. A heterograft was selected in order to decrease the risk of viral transmission as a screened donor was not available. One month postoperatively the graft was vascularized and opaque. The owner failed to return for recheck examinations until 16 months postoperatively at which time only a faint central nebula remained.

Results of diagnostic ophthalmic testing in healthy guinea pigs.

OBJECTIVE-To report values for tear production, central corneal touch threshold (CTT), and intraocular pressure (IOP) in healthy guinea pigs and determine results of aerobic bacterial culture and cytologic examination of conjunctival swab specimens. DESIGN-Cross-sectional study. ANIMALS-31 Healthy guinea pigs (62 eyes) of various ages and breeds. PROCEDURES-Tear production was measured by the phenol red thread tear test (PRT) and Schirmer tear test (STT) before and after topical anesthetic application, CTT was measured with an esthesiometer, and IOP was measured by applanation tonometry. RESULTS-Combining data from all eyes, mean +/- SD PRT values before and after topical anesthetic administration were 21.26 +/- 4.19 mm/15 s and 22.47 +/- 3.31 mm/15 s, respectively, and mean IOP was 18.27 +/- 4.55 mm Hg. Median STT values before and after topical anesthetic administration were 3 mm/min (range, 0 to 12 mm/min) and 4 mm/min (range, 0 to 11 mm/min), respectively, and median CTT was 2.0 cm (range, 0.5 to 3.0 cm). Values did not differ between eyes for any test, but significant differences were identified for PRT values between males and females and between values obtained before and after topical anesthetic administration. Common bacterial isolates included Corynebacterium spp, Streptococcus spp, and Staphylococcus spp. Cytologic examination of conjunctival swab specimens revealed mainly basal epithelial cells; lymphocytes were common. CONCLUSIONS AND CLINICAL RELEVANCE-Results provided information on values for PRT, STT, CTT, and IOP in healthy guinea pigs and on expected findings for aerobic bacterial culture and cytologic examination of conjunctival swab specimens.

Comparison of the efficacy of various concentrations and combinations of serum, ethylenediaminetetraacetic acid, tetracycline, doxycycline, minocycline, and N-acetylcysteine for inhibition of collagenase activity in an in vitro corneal degradation model.

OBJECTIVE To compare the efficacy of various concentrations and combinations of serum, EDTA, 3 tetracyclines, and N-acetylcysteine (NAC) for collagenase inhibition in an in vitro corneal degradation model. SAMPLE Grossly normal corneas from recently euthanized dogs and horses and fresh serum from healthy dogs and horses. PROCEDURES Serum was pooled by species for in vitro use. For each species, sections of cornea were dried, weighed, and incubated with clostridial collagenase (800 U/mL) in 5 mL of a 5mM calcium chloride-saline (0.9% NaCl) incubation solution and 500 µL of 1 of 19 treatments (homologous serum; 0.3%, 1.0%, or 2% EDTA; 0.1%, 0.5%, or 1.0% tetracycline, doxycycline, or minocycline; 0.5%, 1.0%, or 5.0% NAC; serum with 0.5% tetracycline; serum with 1.0% EDTA; or 1.0% EDTA with 0.5% tetracycline). Positive and negative control specimens were incubated with 5 mL of incubation solution with and without collagenase, respectively. Each control and treatment was replicated 4 times for each species. Following incubation, corneal specimens were dried and reweighed. The percentage corneal degradation was calculated and compared among treatments within each species. RESULTS Treatments with tetracyclines at concentrations ≥ 0.5%, with EDTA at concentrations ≥ 0.3%, and with NAC at concentrations ≥ 0.5% were more effective at preventing corneal degradation than serum in both species. The efficacy of each combination treatment was equal to or less than that of its components. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested EDTA, tetracyclines, and NAC may be beneficial for topical treatment of keratomalacia, but in vivo studies are required.

Flaccid skin protects hagfishes from shark bites.

Hagfishes defend themselves from fish predators by releasing large volumes of gill-clogging slime when they are attacked. Slime release is not anticipatory, but is only released after an attack has been initiated, raising the question of how hagfishes survive the initial attack, especially from biting predators such as sharks. We tested two hypotheses that could explain how hagfishes avoid damage from shark bites: puncture-resistant skin, and a loose and flaccid body design that makes it difficult for teeth to penetrate body musculature and viscera. Based on data from skin puncture tests from 22 fish species, we found that hagfish skin is not remarkably puncture resistant. Simulated shark bites on hagfish and their closest living relatives, lamprey, as well as whole animal inflation tests, revealed that the loose attachment of hagfish skin to the rest of the body and the substantial 'slack volume' in the subcutaneous sinus protect hagfish musculature and viscera from penetrating teeth. While recent work has found evidence that the capacious subcutaneous sinus in hagfishes is important for behaviours such as knot-tying and burrowing, our work demonstrates that it also plays a role in predator defence.

In vitro fungistatic and fungicidal activities of silver sulfadiazine and natamycin on pathogenic fungi isolated from horses with keratomycosis.

OBJECTIVE: To evaluate the in vitro antifungal properties of silver sulfadiazine (SSD) and natamycin against filamentous fungi isolated from eyes of horses with keratomycosis. SAMPLE POPULATION: Filamentous fungal isolates obtained from eyes of keratomycosis-affected horses. PROCEDURES: Fungal culture of ocular samples yielded 6 Fusarium spp; 7 Aspergillus spp; and 1 isolate each of Curvularia, Scopulariopsis, Penicillium, and Chrysosporium. For each fungal isolate, minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of SSD and natamycin were determined. RESULTS: For all 17 fungal isolates, SSD MIC distribution ranged from < or = 1 to > 64 microg/mL; MIC50 and MIC90 (MICs at which 50% and 90% of organisms were inhibited) were 4 and 32 microg/mL, respectively. The SSD MFC distribution for all isolates was < or = 1 to > 64 microg/mL; MFC50 and MFC90 (MFCs at which 50% and 90% of organisms were killed) were 8 and > 64 microg/mL, respectively. For all fungal isolates, natamycin MIC distribution ranged from 256 to > 1,000 microg/mL; MIC50 and MIC90 were 512 and > 1,000 microg/mL, respectively. The natamycin MFC distribution for all isolates ranged from 512 to > 1,000 microg/mL; MFC(50) and MFC(90) were each > 1,000 microg/mL. CONCLUSIONS AND CLINICAL RELEVANCE: These in vitro data suggest that SSD is fungicidal against the fungal isolates that were obtained from eyes of horses with keratomycosis and that natamycin is fungicidal against some of the isolates at the drug concentrations evaluated. Silver sulfadiazine may be a therapeutic option for equine keratomycosis.