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Objective To provide an updated overview of feline orbital neoplasia, to compare diagnostic utility of cytology and histopathology, and to evaluate minimally invasive sampling modalities. Procedures A medical records search was performed to identify cats with orbital neoplasia. Data were collected regarding signalment, diagnosis, vision status, imaging modalities, and sample collection methods. A reference population with orbital neoplasia was also identified via literature search for comparison with regard to final diagnosis. Results Eighty-one cats met selection criteria and 140 cases were identified in the literature. In the study and reference populations, respectively, diagnoses were grouped as follows: round cell tumors 47% and 24%, epithelial tumors 38% and 40%, mesenchymal tumors 14% and 34%, and neurologic origin tumors 1% and 2%. The most common diagnoses in both groups were lymphoma and squamous cell carcinoma (SCC). Feline restrictive orbital myofibroblastic sarcoma (FROMS) was common in the reference population but not diagnosed in the study population. Cytology results were available for 41 cats; histopathology results were available for 65 cats. Both cytology and histopathology results were available for 25 cats, in 44% of which cytologic results were overturned. No significant complications were associated with any sampling method. Lack of cats with multiple samples available for histopathology limited comparison between tissue sampling methods. Conclusions Orbital neoplasia is common in cats, with round cell and epithelial tumors diagnosed most commonly in the study population. Histopathology is superior to cytology in providing a definitive diagnosis. Minimally invasive tissue biopsy techniques appear to be safe and effective.

In areas were human visceral leishmaniasis (VL) is endemic, the domestic dog is the main parasite reservoir in the infectious cycle of Leishmania infantum . Development of prophylactic strategies to lower the parasite burden in dogs would reduce sand fly transmission thus lowering the incidence of zoonotic VL. Here we demonstrate that vaccination of dogs with a recombinant 14 kDa polypeptide of L. infantum nuclear transport factor 2 ( Li-ntf2 ) mixed with adjuvant Bp MPLA-SE resulted in the production of specific anti- Li-ntf2 IgG antibodies as well as IFN-γ release by the animals’ peripheral blood mononuclear cells stimulated with the antigen. In addition, immunization with this single and small 14 kDa polypeptide resulted in protracted progression of the infection of the animals after challenging with a high dose of virulent L. infantum . Five months after challenge the parasite load was lower in the bone marrow of immunized dogs compared to non-immunized animals. The antibody response to K39, a marker of active VL, at ten months after challenge was strong and significantly higher in the control dogs than in vaccinated animals. At the study termination vaccinated animals showed significantly more liver granulomas and lymphoid hyperplasia than non-vaccinated animals, which are both histological markers of resistance to infection. Together, these results indicate that the 14 kDa polypeptide is an attractive protective molecule that can be easily incorporated in a leishmanial polyprotein vaccine candidate to augment/complement the overall protective efficacy of the final product.

Objective To evaluate the use of cyanoacrylate adhesive as an adjunct to lamellar keratectomy in cats with corneal sequestrum. Methods Medical records were reviewed to identify cats with naturally occurring midstromal corneal sequestra treated with lamellar keratectomy and cyanoacrylate adhesive. All cats also had a bandage contact lens placed for postoperative comfort. Data collected included breed, age, sex, and reproductive status of the cat, eye involved, presence or absence of neovascularization at the time of surgery, history of prior sequestra, additional ocular procedures performed, use of neuromuscular blocking agents, procedure time, time to cessation of topical medications, time to recurrence or last follow-up, and complications aside from recurrence. Results Sixteen cats met study criteria, with a median follow-up time of 17.5 months in those without recurrence. Median time to cessation of topical medications was 4 weeks. Fourteen cats (87%) have not experienced recurrence. Other than recurrence in two cats, no significant complications were noted. Aside from purebred status, no commonalities were found between the two cats with recurrence. Neuromuscular blocking agents were not used during surgery in most cases. Median procedure time was 10 minutes. Conclusions Cyanoacrylate adhesive is an effective and safe alternative to grafting procedures in cats undergoing lamellar keratectomy for treatment of corneal sequestrum. Recurrence rates are comparable to those seen with grafting techniques. Benefits of this approach include decreased anesthesia time, lower procedure costs, and short duration of postoperative treatment.

The aqueous humor (AH) is the fluid that fills the anterior and posterior chambers of the eye. Its main roles are to provide nourishment and metabolic waste removal to active metabolic ocular structures that are avascular and to contribute maintaining a normal intraocular pressure (IOP) without altering the refractive status of the eye. Its composition and the fluid dynamics associated with its flow are voluble and undergo changes associated with age and disease. Of particular importance is that the resistance to the outflow of AH from the anterior chamber is influenced by morphologic, physiologic, and biochemical dynamic factors.1 Beside aqueous nutritional importance, its solutes also participate in establishing the anterior chamber associate immune deviation, and carry and distribute the different proteins and molecules that promote and direct tissue remodeling and changes in the anterior segment that are associated with both age and disease.

Objective—To investigate whether differences existed between clinically normal dogs and dogs with goniodysgenesis-related glaucoma (GDRG) in serum autoantibodies against optic nerve antigens. Animals—16 dogs with GDRG, 17 healthy dogs with unremarkable pectinate ligament and iridocorneal angle morphology, and 13 euthanized dogs with no major ocular abnormalities or underlying diseases. Procedures—Western blotting was performed with optic nerve extracts from the euthanized dogs as an antigen source and serum from clinically normal dogs and dogs with GDRG as a primary antibody (autoantibody) source. Blots were evaluated for presence and density of bands. Results—Multiple bands were identified on western blots from all dogs with GDRG and all clinically normal dogs, with a high degree of variability among individual dogs. Dogs with GDRG were significantly more likely than healthy dogs to have bands present at 38, 40, and 68 kDa. Dogs with GDRG had significant increases in autoreactivity at 40 and 53 kDa and a significant decrease in autoreactivity at 48 kDa. Conclusions and Clinical Relevance—Significant differences in serum autoantibodies against optic nerve antigens were found in dogs with versus without GDRG. Although it remains unclear whether these differences were part of the pathogenesis of disease or were sequelae to glaucomatous changes, these findings provide support for the hypothesis that immune-mediated mechanisms play a role in the development or progression of GDRG. However, the high degree of variability among individual dogs and the considerable overlap between groups suggest that the clinical usefulness of this technique for distinguishing dogs with GDRG from clinically normal dogs is likely limited.

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).

We present a series of three American Bulldogs with clinical signs of glaucoma and intraocular inflammation accompanied by bilateral uveal cysts and abnormal gonioscopic findings. All dogs proved refractory to medical management and were enucleated. Histopathologic findings were similar in all three and included significant preiridal fibrovascular membranes and mononuclear inflammatory infiltrates in the anterior uvea. On microscopic evaluation, cysts appeared to arise primarily from the ciliary body and iridociliary sulcus, with smaller cysts also budding from the posterior iris. Pigment dispersion was variable but consistent, involving deposition of a small number of pigment-laden cells in the dependent trabecular meshwork. Cataract formation was not noted. Glaucoma associated with uveal cysts has been described previously in Golden Retrievers and Great Danes, although clinical and histopathologic findings in those breeds are not identical to those described here. American Bulldogs with uveal cysts should have gonioscopy performed and should be monitored carefully for signs of increased intraocular pressure and intraocular inflammation. Furthermore, documentation of cyst-associated glaucoma in a third breed suggests clinicians should exercise caution in dismissing uveal cysts in dogs as incidental findings.

We present a case of reactive histiocytic disease involving the orbit, optic nerve, retina, and choroid in a Border Collie dog initially presenting for vision loss. Long-term partial return of vision has been achieved with systemic immunosuppression. Anterior segment and ocular surface manifestations of reactive histiocytic disease in dogs are relatively common. Posterior segment and orbital involvement, however, are minimally documented in the existing literature. To the authors' knowledge, this is the first report of disease confined to the orbit and posterior segment as well as the first report of vision loss as a presenting complaint for reactive histiocytic disease. Clinical, magnetic resonance imaging, cytologic, and histopathologic findings are reviewed.

Objective The aim of the study was to evaluate the efficacy, outcome, and complications following penetrating sclerokeratoplasty and frozen homologous corneoscleral grafting for the management of extensive canine epibulbar melanocytomas. Methods Medical records of canine patients treated at three different veterinary hospitals between 1999 and 2010 were reviewed. Signalment, location and extent of melanocytomas, recurrence rate, and early and late complications were reported. Patients were re-examined postoperatively to provide follow-up information. Results Patients included one intact male, three castrated males, six intact females, and one spayed female, with a median age of 5 years (range, 3–9). German Shepherds were overrepresented. Tumors extended from 2 to 4 clock hours at the limbus and up to 17 mm from clear cornea to globe equator. One case showed iridocorneal angle invasion; corneal involvement was present in all cases, and lipid keratopathy was present in four cases. In two cases, there was incomplete resection owing to tumor extent. Follow-up time ranged from 3 to 72 months (median, 17 months), with one case of intraocular tumor progression. Early complications included anterior uveitis (11/11), intracameral fibrin (5/11), hyphema (4/11), corneal edema (4/11), exuberant corneal granulation tissue (2/11), focal retinal edema (1/11), dyscoria (1/11), and partial suture dehiscence (1/11). Late complications included corneal fibrosis and/or pigmentation (11/11), faint anterior cortical cataracts (3/11), and lipid keratopathy (1/11). Vision was retained in all cases. Conclusions This technique offers a surgically challenging but effective treatment for extensive epibulbar melanocytomas. In this case series, complications were mild and transient, with preservation of ocular anatomy and function.

Purpose To describe histologic anterior segment changes in eyes affected with primary lens displacement (PLD) and secondary glaucoma. Methods Histologic sections stained with H&E from canine eyes enucleated because of PLD and secondary glaucoma were examined. Results Thirteen eyes from 12 patients were evaluated. Four dogs were castrated males and eight spayed females. Median age was 8 years of age (range 3–13). Breeds included seven terriers and five other breeds. All eyes examined demonstrated varying degrees of inflammation involving the iris and cleft. Mononuclear and melanophagic infiltration of the cleft was found in all specimens. Four globes also showed polymorphonuclear infiltrate. Pre-iridal fibrovascular membranes were clearly identified in 10 of 13 eyes. Total inflammatory score was significantly greater in all globes examined compared with an age-matched group of normal dogs. The posterior pigmented iris epithelium demonstrated a consistent pattern of hyperplasia and/or hypertrophy and cystic degeneration, more prominent in the more central regions. In some cases, hyperplasia was of greatest severity in the mid-iris and associated with thinning or flattening of the pupillary region. Conclusions These results suggest that lens instability may be associated with chronic inflammation and secondary glaucoma. Mechanical irritation from an unstable lens may result in hypertrophy and/or hyperplasia of the posterior pigmented iris epithelium and subsequent cellular exfoliation and release of melanin. An inflammatory reaction directly or indirectly related to melanin release may obstruct the outflow pathways ultimately leading to glaucoma and loss of vision. Use of topical steroids may be warranted in dogs with PLD.

A 2-year-old male castrated Springer Spaniel with a 3-week history of waxing and waning right sided exophthalmos, periorbital swelling, chemosis, and fundic changes was examined. Ophthalmic examination of the right eye revealed slight chemosis and nictitating membrane protrusion. Indirect ophthalmoscopy showed an approximately 8 mm peripapillary hyporeflective tapetal lesion with subretinal edema consistent with a bulbar/retrobulbar disease process. Inflammatory or neoplastic diseases were the main differential diagnoses. Ancillary diagnostics (ocular ultrasound and computed tomography) showed a focal, poorly defined dense tissue involving the caudomedial aspect of the right globe, adjacent to the optic nerve head without apparent orbital involvement. Considering the duration, location, and severity of the clinical findings, enucleation of the right globe was performed. Histopathology revealed focal thickening of the posterior wall with severe pyogranulomatous inflammation, surrounding a foreign body most consistent with plant material embedded between the sclera and the choroid (suprachoroidal). This report describes a rare case of a scleral/suprachoroidal foreign body (plant material), and outlines the difficulty of establishing an etiological diagnosis using standard ocular imaging.

We present a report describing use of a 360-degree conjunctival graft for management of progressive keratomalacia refractory to medical treatment in a 5-month-old American Cocker Spaniel. In the dog of this report, the extension of melting to nearly the entire corneal surface limited surgical options. Following surgery and later resection of the graft, the patient is visual with minimal corneal opacity. Numerous corneal grafting techniques have been described in companion animals, but require special materials and may not be possible when melting is extensive. Although older animals or animals with additional corneal pathology may have less ideal outcomes in terms of corneal clarity than the patient of this report, we believe that 360-degree conjunctival grafting offers a viable and cost-effective option for management of cases with extensive keratomalacia that may otherwise have resulted in enucleation.

Objective Evaluate the influence of topically applied flurbiprofen 0.03% and latanoprost 0.005%, alone or in combination, in normal canines. Animals studied 10 Normal Beagles. Procedures Intraocular pressure (IOP), pupil size, aqueous flare, conjunctival hyperemia, and blepharospasm were evaluated bilaterally five times daily (8 am, 11 am, 2 pm, 5 pm, and 8 pm). The study consisted of a training and acclimation period, followed by 3, 1-week experiment periods. A 2-week washout period occurred between each experiment period. During period 1, all dogs received flurbiprofen (three doses 6-h apart) in the treated eye, whereas in period 2, all dogs received latanoprost (one dose 24-h apart). During period 3, both latanoprost (one dose 24-h apart) and flurbiprofen (three doses 6-h apart) were administered in the treated eye. Results Flurbiprofen resulted in a mean IOP elevation of 1.1 mmHg (8.65%) in the treated eye, as compared with the control eye. No effect on pupil size, conjunctival hyperemia, or aqueous flare was noted. Latanoprost resulted in a mean IOP reduction of 3.4 mmHg (30.19%). Combined latanoprost and flurbiprofen resulted in a mean IOP reduction of 2.7 mmHg (24.56%). Miosis was noted in the treated eyes during both latanoprost periods, with maximal pupil constriction 3-h post-dose. This was followed by relative mydriasis 24-h post-dose, persisting 48 h after the last dose. The degree of conjunctival hyperemia varied between individuals. Neither blepharospasm nor aqueous flare was noted at any time point. Conclusion Concurrent administration of latanoprost and flurbiprofen resulted in a 20.41% reduction in the ocular hypotensive effect relative to latanoprost therapy alone.

After a brief review of cryptococcosis in dogs and cats from the literature from 1980 to 92, three cases in dogs (two epidemiologically strictly connected) and two in cats are reported. In the three dogs and in one of the two cats lesions were seen in many sites, but only one dog and one cat had a central nervous system localization. The cutis was affected in the three dogs and in one cat; in two of the dogs it was probably the primary lesion, and in the cat it was the only lesion. An unidentified genetic defect was probably the predisposing factor in two of the dogs of the same litter, exposed to soil cryptococcal contamination (from pigeon guano); a third dog, of different breeding, was not infected. Steroid treatment was predisposing in one cat. Flucytosine treatment was initially successful in two dogs, but in both relapses were reported; in one dog fluconazole treatment was successful. The isolates, before and after treatment, demonstrated a large increase in flucytosine MIC, strictly connected with the relapse.

Although the clinical classification of primary glaucoma in dogs is quite simple, the phenotypes of glaucoma in most of the species are indeed multiple. Ophthalmologists can often evaluate the dynamic changes of clinical signs at different times in the course of the disease, whereas pathologists are often presented with globes that have undergone abundant therapies and are at the end stage. Therefore, an open collaboration between clinicians and pathologists can produce the most accurate interpretation in the pathology report and improve patient outcomes. This article focuses on the histomorphologic elements that characterize, and are important to, canine primary glaucomas.

Glaucoma is a common ocular condition in humans and dogs leading to optic nerve degeneration and irreversible blindness. Primary glaucoma is a group of spontaneous heterogeneous diseases. Multiple factors are involved in its pathogenesis and these factors vary across human ethnic groups and canine breeds, so the clinical phenotypes are numerous and their classification can be challenging and remain superficial. Aging and oxidative stress are major triggers for the manifestation of disease. Multiple, intertwined inflammatory and biochemical cascades eventually alter cellular and extracellular physiology in the optic nerve and trabecular meshwork and lead to vision loss.

Glaucoma is a painful and often blinding group of ocular diseases for which there is no cure. Although the definition of glaucoma is rapidly evolving, elevated intraocular pressure (IOP) remains the most consistent risk factor of glaucoma in the canine patient. Therapy should be aimed at neuroprotection. The mainstay of therapy focuses on reducing IOP and maintaining a visual and comfortable eye. This article discusses the most current ocular hypotensive agents, focusing on their basic pharmacology, efficacy at lowering IOP, and recommended use in the treatment of idiopathic canine glaucoma.

Objective To evaluate the ophthalmoscopic, fluorescein angiographic and light microscopic effects of diode laser retinopexy application in the tapetal and nontapetal fundus in the dog, and to ascertain appropriate laser power settings for production of photocoagulative lesions in these two regions. Animals studied Three adult female Beagle dogs. Procedures Laser burns were applied to selected areas in the fundus with an indirect headset delivery system using settings varying from 100 to 200 milliWatts (mW) and from 100 to 600 milliSeconds (mS) with total delivered energy ranging between 15 and 100 milliJoules (mJ). The dogs were then monitored by ophthalmoscopic examination and fluorescein angiography at regular intervals for 7–28 days. Histopathologic studies were performed at 7, 14 and 28 days after laser application. Results The diode laser produced ophthalmoscopically visible lesions in the nontapetal fundus with all laser settings used, and the appearance of these lesions corresponded to the energy levels used, and degree of pigment in the lased region. Gray-white colored lesions with minimal subsensory retinal edema were seen with settings as low as 100 mWatts/150 mSeconds. In the tapetal fundus, laser burns were more difficult to produce, less repeatable, and required higher energy levels. Laser burns appeared as bronze, dark green or black discolorations of the tapetum with varying degrees of subsensory retinal edema. Lesions were more reproducible and were achieved with lower settings in the tapetal area of the tapetal/nontapetal junction. Ophthalmoscopically, depigmentation and repigmentation of the RPE (nontapetal fundus) and degenerative changes in the overlying retina (tapetal fundus) developed in the laser burns over the 28-day study period. Fluorescein angiographic studies showed disruption of the blood–retinal barrier at the level of the RPE and fluorescein leakage into the subsensory retinal space was seen in most lesions at 24 h, was minimal at 3 days, and had resolved by 7 days. Histologically, grayish-white lesions in the nontapetal fundus, and bronze to small black lesions in the tapetal fundus were typically characterized by outer retinal necrosis and RPE migration. Gliosis was considered minimal, was confined to the retina, and no inflammatory cells were seen. Peripheral intense white lesions (nontapetum) and lesions with a black center (tapetal fundus) were characterized by more extensive panretinal and choroidal necrosis. Most of the nontapetal lesions and a few in the tapetal fundus showed the formation of a central retinal detachment. Conclusions The diode laser effectively produces lesions suitable for retinopexy in both the nontapetal, pigmented fundus and the tapetal fundus, although variably so in the latter region. Initial laser settings of 100–150 mW/200 mS for the pigmented fundus, and 150 mW/200–300 mS for the peripheral tapetal fundus are recommended, and the clinician should gradually increase time interval settings to achieve a grayish-white lesion in the nontapetum, and a bronze to slightly black lesion in the tapetal fundus. If possible, retinopexy should be applied to the peripheral tapetal area or tapetal/nontapetal junction.

Objective—To characterize clinical and clinicopathologic findings, response to treatment, and causes of systemic hypertension in cats with hypertensive retinopathy. Design—Retrospective study. Animals—69 cats with hypertensive retinopathy. Procedure—Medical records from cats with systemic hypertension and hypertensive retinopathy were reviewed. 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 14-year-old 8.2-kg (18.04-lb) castrated male Cairn Terrier with chronic keratoconjunctivitis sicca in the left eye was evaluated because of severe blepharospasm and a black plaque of 3 weeks’ duration. Clinical Findings—Abnormalities of the left eye included a decreased Schirmer tear test value and the presence of a brownish-black plaque in the center of the cornea. The plaque was surrounded by fibrovascular tissue except at the medial aspect where there was mild malacia of the adjacent corneal stroma. Treatment and Outcome—The plaque was removed by superficial keratectomy, and a conjunctival graft was performed. Histologic evaluation of the plaque and surrounding cornea revealed ulceration, stromal necrosis, and chronic suppurative keratitis with fibrosis and neovascularization. Evaluation of plaque sections that were stained with Gram and Von-Kossa stains yielded negative results for bacteria and mineralization, respectively; examination of sections stained with periodic acid–Schiff stain revealed multiple intracytoplasmic inclusions in macrophages. Virus isolation and a PCR assay for canine herpesvirus yielded negative results. Transmission electron microscopy revealed collagen disruption with interspersed macrophages and apoptotic keratocytes; no viral particles or evidence of other infectious agents was observed. The graft healed without complication and was trimmed 2 weeks after surgery. Four months after surgery, the Schirmer tear test value remained decreased from reference limits despite topical tacrolimus treatment, and pigmentary keratopathy was present surrounding the graft. Clinical Relevance—Corneal sequestra are rare in species other than cats. In this dog, it was possible that chronic keratoconjunctivitis sicca might have contributed to the development of the corneal sequestrum.