Retrobulbar pigmented peripheral nerve sheath tumor in a dog.

A 1-year-old male castrated Pug was referred for unilateral exophthalmos unresponsive to oral antibiotic and anti-inflammatory therapy. Clinical findings included exophthalmos of the left eye with lateral strabismus, resistance to retropulsion, and an elevated nictitans. Hematologic and biochemical analyses were within normal limits. Findings following computed tomography (CT) of the head included an expansile retrobulbar soft tissue mass with bony lysis extending into the left nasal cavity and nasopharynx. Ultrasound-guided fine-needle aspirates and biopsy samples obtained via rhinoscopy were nondiagnostic. Palliative exenteration was elected; the patient was euthanized 13 weeks following exenteration due to development of neurologic signs and perceived poor quality of life. The histopathologic diagnosis was a malignant pigmented peripheral nerve sheath tumor.

Equine orbital fractures: a review of 18 cases (2006-2013).

OBJECTIVE: To review the clinical features, treatments, complications, and outcomes of horses with traumatic orbital fractures. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Eighteen horses with confirmed orbital fractures. PROCEDURES: Medical records of horses presenting with orbital fractures between 2006 and 2013 were reviewed. Signalment, etiology of fracture, clinical signs, fracture descriptions, diagnostic imaging, treatments, complications, and outcomes were evaluated. RESULTS: Eighteen horses presented with orbital fractures resulting from rearing in a confined space (n = 5), being kicked (4), colliding with a stationary object (3), and unknown trauma (6). Radiography and computed tomography were effective at classifying fractures and evaluating sinus/nasal involvement. Epistaxis/sinusitis were associated with fractures of the zygomatic process of the temporal bone (n = 3) and comminuted fractures of multiple bones (5). Seventeen fractures required treatment, with fifteen receiving a combination of medical and surgical therapy. Surgery included reduction of large bony fragments (n = 8), removal of small fragments (12), stabilization with a wire implant (1), and sinus trephination and lavage (5). Factors contributing to a favorable outcome included: globe retention (n = 16), vision (14), comfort (15), cosmesis (9), and return to previous function (13). CONCLUSIONS: Horses sustaining orbital fractures treated promptly with medical and surgical therapy have a favorable prognosis for return to function and cosmesis. Fractures affecting the zygomatic process of the frontal bone are unlikely to involve the sinus/nasal cavities. Epistaxis and sinusitis warrant more aggressive therapy and decrease functional and cosmetic outcome.

Trans-corneal reduction of anterior lens luxation in dogs with lens instability: a retrospective study of 19 dogs (2010-2013).

OBJECTIVE: To evaluate the success rate and outcome of trans-corneal reduction of anterior lens luxation (TR-ALL) in dogs with lens instability. ANIMALS STUDIED: Nineteen dogs with anterior lens luxation. PROCEDURES: Medical records of dogs with anterior lens luxation (ALL) were reviewed: dogs were included if TR-ALL was performed followed by medical therapy in the form of topical 0.005% latanoprost ophthalmic solution. The duration of ALL, vision status, ophthalmic examination abnormalities, reason for performing TR-ALL and details of TR-ALL were recorded. Success rate for TR-ALL as well as postprocedure complications were also assessed. RESULTS: Twenty eyes from 19 dogs met the inclusion criteria. Median age was 6.5 years (0.3-15 years) and 47% were terriers (9/19). Successful TR-ALL was achieved in 85% of eyes (17/20); failure was attributed to posterior synechia or vitreous expansion. Short-term complications included corneal ulceration (2/20) and anterior uveitis (3/20); recurrence of anterior luxation occurred in only one dog. Median follow-up for visual eyes (11) following successful TR-ALL was 353 days (range of 1 to 1182 days). Vision was retained in 54.5% (6/11) of eyes with a median time to vision loss of 12 months as a result of glaucoma or presumed retinal detachment. CONCLUSIONS: Trans-corneal reduction of ALL provides a non-surgical alternative to intracapsular lens extraction (visual eyes) or enucleation (nonvisual eyes) in dogs. Long-term visual outcome of TR-ALL is comparable to intracapsular lens extraction for ALL.

Characterization of fungal keratitis in alpacas: 11 cases (2003-2012).

OBJECTIVE: To describe clinical, microbiological, in vivo confocal microscopic, and histopathologic features of fungal keratitis in alpacas and to estimate prevalence of the disease in a population of alpacas from the northeastern United States. DESIGN: Retrospective case series. Animals-11 alpacas. PROCEDURES: Medical records of alpacas evaluated by the ophthalmology service of a veterinary teaching hospital were searched to identify animals with a clinical diagnosis of fungal keratitis and positive results for fungal culture of a corneal sample between 2003 and 2012. Signalment and historical, clinical, and microbiological details were recorded. Results of cytologic, histopathologic, and in vivo confocal microscopic corneal examinations were collected when available. RESULTS: Fungal keratitis was diagnosed in 11 of 169 (6.5%) alpacas that underwent ophthalmologic examination by the ophthalmology service during the study period. Ten of the 11 alpacas were evaluated in the summer or fall months. Corneal lesions included stromal ulcer, stromal abscess, corneal perforation, and nonulcerative keratitis. Aspergillus fumigatus and Fusarium solani were the most frequently cultured fungi. Fungi were also identified through corneal cytologic examination, histologic examination, or in vivo confocal microscopy in 9 alpacas. Historically, 2 alpacas were evaluated following external ocular trauma and 1 following corneal foreign body removal. Nine alpacas had received topical treatment with antimicrobials and 2 had antimicrobial-corticosteroid combinations administered topically prior to referral. Nine of 10 alpacas for which follow-up information was available were successfully treated, with globe and vision retention. CONCLUSIONS AND CLINICAL RELEVANCE: Fungal keratitis was a relatively common ocular disease in this population of alpacas and appeared to share several clinical features with keratomycosis in horses.

Effect of short-term diphenhydramine administration on aqueous tear production in normal dogs.

OBJECTIVE: To perform a randomized, placebo-controlled, masked clinical trial using a cross-over design to determine the effect of oral diphenhydramine on aqueous tear production in normal dogs. ANIMALS STUDIED: Seventeen dogs with normal ophthalmic examinations. PROCEDURES: Baseline tear production was established for each dog by performing Schirmer tear test I (STT I). Dogs received 20-day treatment courses of both oral diphenhydramine and placebo solutions with a 10-day washout period between treatment periods. Each dog was randomly assigned to receive diphenhydramine or placebo at the outset of the study. Measurements of STT I values were measured at regular intervals during the study and were conducted at the same time of day throughout the study to control for diurnal variations in tear production. The significance of the impact of diphenhydramine treatment on the quantity of aqueous tear production, as determine by STT results over time, was evaluated using regression analysis with appropriate transformation. RESULTS: Statistical comparisons at each measurement time, including baseline measurements between control and treatment groups, revealed no significant differences. Mean STT I levels also did not differ significantly at any measurement time compared to baseline for treatment or control groups. CONCLUSIONS: Short-term administration of oral diphenhydramine does not result in a significant decrease in aqueous tear production in normal dogs.

Periocular cutaneous mast cell tumors in cats: evaluation of surgical excision (33 cases).

OBJECTIVE: To describe feline periocular cutaneous mast cell tumor (CMCT) clinical features, rates of local tumor recurrence and metastases, and cat survival time following surgical excision. ANIMALS STUDIED: Thirty-three cats with periocular CMCTs. PROCEDURES: Medical records of cats diagnosed with periocular CMCTs were reviewed; cats were included if CMCTs were surgically excised and the diagnosis confirmed by histopathology. The appearance, size, location and histopathology findings of CMCTs were recorded. Rates of local recurrence, metastasis, and survival time following surgical excision were collected when available. RESULTS: All periocular CMCTs were restricted to the eyelids. In addition to surgical excision, three cats were treated with adjunctive therapy (strontium-90 irradiation or cryotherapy) intraoperatively. Local tumor control was achieved in 22/23 cats with a minimum follow-up of 30 days (median follow-up time of 711 days); one cat developed disseminated CMCTs but no local recurrence. Cats with periocular CMCTs had a median survival time of 945 days. Metastatic disease involving peripheral lymph nodes or abdominal viscera was not detected in any cat at any time during the study. All periocular CMCTs were classified as low-grade based on histopathology, and complete excision was achieved in approximately 50% of cases. CONCLUSIONS: Surgical excision of periocular CMCTs in cats is an effective treatment option with rare local recurrence and metastases, even following incomplete surgical excision.

Acute blindness in dogs: sudden acquired retinal degeneration syndrome versus neurological disease (140 cases, 2000-2006).

OBJECTIVE: To evaluate dogs with amaurosis and compare signalment, history, ophthalmic examination and neurologic abnormalities between dogs diagnosed with sudden acquired retinal degeneration syndrome (SARDS) versus neurological disease (ND). Animals Studied-140 dogs with acute vision loss and ocular abnormalities insufficient to account for visual deficits. An electroretinogram (ERG) was performed on each dog. PROCEDURES: Medical records were reviewed and information was collected for all dogs meeting the inclusion criteria. Dogs diagnosed with SARDS were compared to those with ND based on signalment, duration of clinical signs, past medical problems, clinicopathologic findings, and ophthalmic and physical examination abnormalities. RESULTS: 120 dogs were diagnosed with SARDS and 20 dogs with ND based on ERG results. Mixed-breed dogs were most commonly diagnosed with SARDS as well as ND. Pure breed dogs frequently diagnosed with SARDS included the Miniature Schnauzer and Dachshund. Dogs with SARDS did not differ significantly from those with ND based on age or sex distribution. Cushing's-like symptoms were reported more frequently in SARDS dogs as well as conjunctival hyperemia and retinal vascular attenuation. Papilledema and asymmetric visual deficits were observed more frequently in dogs with ND. Dogs with ND were no more likely than SARDS dogs to have additional neurological deficits. CONCLUSIONS: Appreciable overlap of clinical signs exists between dogs with SARDS and dogs with ND resulting in acute vision loss. As a significant portion of dogs (14%) in the present study were diagnosed with ND, an ERG to rule out ND is indicated in dogs with amaurosis.