Clinical parameters obtained during tear film examination in domestic rabbits.

BACKGROUND: One of the contributing factors to ocular surface health is a stable precorneal tear film. Considering the increasing interest in rabbits as pets and the limited literature available on domestic rabbit tearing, the aim of this study was to establish normative data for examination of the tear film in domestic rabbits. RESULTS: The study included 75 client-owned domestic Holland Lop rabbits (150 eyes). The following examinations were performed in each eye: Schirmer tear test-1, tear osmometry, interferometry, tear meniscus height measurement and meibography (quantifying meibomian gland loss as a percentage). The resulting median (95% central range) values were 10.0 (5.0-17.3) mm/min for the Schirmer tear test-1, 345.0 (280.5-376.1) mOsm/L for tear osmolarity, grade 2 (1-4) of interferometry, 0.28 (0.20-0.47) mm for tear meniscus height and 0.0 (0.0-67.6) % meibomian gland loss. A significant association was found between tear osmolarity and age, with an estimated decrease of - 4.0 mOsm/L with each additional year of age (p < 0.001). The distributions of interferometry grades were significantly different between males and females (p < 0.001), with grade 1 and grade 2 being the most frequent in females and males, respectively. A weak negative correlation was also observed between interferometry grade and the percentage of meibomian gland loss (r = - 0.22, p = 0.006). CONCLUSIONS: This is an original study that documents extensive tear film parameters in healthy Holland Lop rabbits. The results can be used as normative data for the examination of the tear film in this lagomorph breed.

Conjunctival Extramedullary Plasmacytoma in Dogs and a Cat: Clinical Characteristics and Histopathological Findings.

BACKGROUND: Extramedullary plasmacytoma (EMP) is a plasma cell tumor that is very rarely reported in ocular and adnexal tissue and is usually solitary and benign. METHODS: This study evaluated seven cases from different ophthalmology referrals submitted for histopathological analysis between 2013 and 2022. RESULTS: EMPs were diagnosed in a 9-year-old domestic short-haired cat and in six dogs (median age, 10 years): three English Cocker Spaniels, a Golden Retriever, a Maltese, and a Pinscher. EMPs affected the third eyelid conjunctiva in five cases (5/7), followed by the superior bulbar (1/7) and palpebral conjunctivae (1/7), respectively, and were presented mostly as well-defined, salmon-colored nodules. Histopathologically, the masses were composed of sheets and packets of round cells morphologically consistent with mature plasma cells with mild anisocytosis and anisokaryosis; mitosis and binucleated giant cells were rarely observed. Follow up for 6/7 cases ranged from 6 months to 2 years. No signs of recurrence or systemic involvement (multiple myeloma) were observed. CONCLUSIONS: EMP should be included in the differential diagnoses of canine and feline conjunctival masses. Staging recommendations should include multiple myeloma diagnostic evaluation. Our results suggest that primary conjunctival EMP does not appear to be locally aggressive and has low systemic involvement behavior. The local surgical excision alone or combined with cryotherapy should be curative.

A Case of Sebaceous Adenitis and Concurrent Meibomian Gland Dysfunction in a Dog.

Sebaceous adenitis and concurrent meibomian gland dysfunction (MGD) were diagnosed in a two-year-old mongrel dog presenting with hypotrichosis, exfoliative dermatitis and blepharitis. Diagnosis of sebaceous adenitis was based on history, clinical signs, the histological demonstration of multifocal lymphohistiocytic and neutrophilic inflammation targeting the sebaceous glands and sebaceous glands loss. MGD was diagnosed by non-contact infrared meibography followed by tear film lipid layer interferometric evaluation. Ciclosporin and sebolytic shampoos controlled the dermatological condition, while doxycycline, warm compresses, palpebral massages and tobramycin/dexamethasone ointment controlled the blepharitis. This case report should stimulate clinicians to investigate MGD in dogs suffering from sebaceous adenitis, because the meibomian and sebaceous glands share similar anatomy and physiology.

Meibomian gland dysfunction (MGD), as diagnosed by non-contact infrared Meibography, in dogs with ocular surface disorders (OSD): a retrospective study.

BACKGROUND: Meibomian gland dysfunction (MGD) is one of the possible conditions underlying ocular surface disorders (OSD). Prevalence of MGD in dogs affected by OSD has not yet been reported. We aimed to evaluate the prevalence of MGD among OSD canine patients, which had been assessed by non-contact infrared meibography and interferometry, and to identify MGD associated factors that might guide its diagnosis. Medical records of canine patients examined for OSD between 2016 and 2019 were reviewed. The frequency of MGD was evaluated within different categories (skull conformation, gender, eye and STT-1). The putative MGD risk factors and frequency of MGD within grades of interferometry were evaluated in a regression analysis model and reported as odd ratios (ORs). RESULTS: One hundred fifty eyes from 81 dogs with OSD were included with median age 75 months (range 3-192) and female representation with 52%. MGD was present in 70% of the examined eyes. MGD risk was higher in males ORadj = 3.015 (95% CI: 1.395-6.514) (P = 0.005) and older patients ORadj = 1.207 (95% CI: 1.081-1.348) (P = 0.001). No significant differences were found between left and right eyes (P = 0.66) or between the two types of skull conformation (P = 0.477) and MGD presence. MGD was associated to the lowest lipid layer (LL) thickness, as assessed by interferometry (grade 0) OR = 16.00 (95% CI: 2.104-121.68) (P < 0.001). STT values were not significantly associated with the presence of MGD (P > 0.05). CONCLUSIONS: MGD is a common underlying pathology in OSD. Being male and higher age are risk factors for MGD. An interferometry grade 0 may guide OSD diagnosis towards MGD.

Epidemiology of ocular disorders presumed to be inherited in three large Italian dog breeds in Italy.

OBJECTIVE: To describe the epidemiology and the types of eye disorders that are presumed to be inherited (PIED) in three large Italian dog breeds. ANIMALS: Three large Italian dog breeds: Neapolitan Mastiff (FCI code: 197), Maremma Sheepdog (FCI code: 201), and Italian Corso dog (FCI code: 343). PROCEDURES: All dogs that underwent a complete ophthalmic examination between 1992 and 2012 were included in this prospective observational study. The prevalence of eye disorders with 95% confidence intervals was reported for presumed healthy dogs and for dogs referred to a veterinary center for an ophthalmic consultation. Univariate and multivariate logistic regression techniques were used to generate odds ratios. RESULTS: Of 605 dogs examined during the study period, 351 dogs were affected by at least one PIED (58%; 95% CI: 54-62%). The prevalence of PIED was significantly lower in dogs presented for ophthalmic examination (53.8%) as compared to presumed healthy dogs (62.2%)(OR: 1.4; 95% CI: 1.02-1.9; P = 0.037). Also after multivariate adjustment for the period of observation, the odds of Neapolitan Mastiff (92.1%; OR: 21.4; 95% CI: 11.1-41.4) and of Cane Corso (57.7%; OR: 2.5; 95% CI: 1.7-3.6) suffering a PIED were greater than the Maremma Sheepdog (35.4%). The most common PIED in each breed were entropion (24.3% of all the PIED) in the Neapolitan Mastiff, ectropion (36.6%) in the Corso dog, and cataract (27.9%) in the Maremma Sheepdog. CONCLUSIONS: Clinicians should be aware that three large Italian dog breeds frequently suffer PIED. Breed standards should be reconsidered, and breeding programs should be directed at limiting such disorders.

Conjunctival dacryops in two golden retrievers.

Two 5-month-old golden retriever dogs were referred for the evaluation of a mass arising from the left ventrolateral conjunctiva of the lower eyelid. The masses were externally located, deemed to be cystic in nature, and were surgically removed, and in one case, 0.15 mL of clear fluid was collected. Cytological examination of the aspirated fluid revealed proteinaceous, basophilic amorphous material, and few epithelial cells with foamy cytoplasm and small nuclei. No micro-organisms were detected. Histological examination of the cysts showed a wall composed of single to double cell layers. The cells were cuboidal to flattened, nonciliated, lined with mild submucosal connective tissues and slight inflammation composed of lymphocytes, plasma cells, and rare macrophages. In some areas, lobules of acinar glandular tissue were observed. To the authors' knowledge, this is the first case report of conjunctival dacryops in dogs. The complete surgical removal of the cysts was curative in both cases.

Invasive mould infections of the naso-orbital region of cats: a case involving Aspergillus fumigatus and an aetiological review.

CASE AND CONTEXT: This report describes a cat diagnosed with sinonasal-orbital Aspergillus fumigatus infection using advanced imaging, histopathology and culture. Aetiology, clinical aspects and treatment of this rare and devastating infection are discussed with reference to a literature review of invasive mould (ie, filamentous fungal) infections involving tissues of the naso-orbital region of cats. PRESENTATIONS: Invasive fungal infections can present with different localisations (nasal passages, sinuses, orbits, subcutaneous space, palate, etc) depending on the species involved and its means of introduction into the tissues. Localised subcutaneous lesions (swellings, ulcerations, masses, nodules, etc), without concomitant signs of nasal/orbital disease, generally result from traumatic injuries and subsequent inoculation of fungal spores into the subcutaneous space. In contrast, naso-ocular involvement and concurrent signs of nasal disease (nasal discharge, sneezing, masses protruding from the nostrils) generally result from inhalation of spores, with subsequent spread of infection into the nasal planum or penetration of overlying bone and invasion of the subcutaneous space. Aspergillus species typically show such an invasion mechanism and frequently affect orbital tissues. Dematiaceous fungi (ie, filamentous fungi with brown/black hyphae) are reported to cause solitary, less invasive, slowly developing lesions, probably as a result of traumatic injuries with inoculation of fungal propagules. Accordingly, the subcutaneous space is more frequently primarily involved. TREATMENT AND OUTCOME: Whatever the mould species, reported treatment options include surgery and a series of antifungal drugs. The outcome is frequently poor, especially for Aspergillus infections, although various measures can be taken to maximise the chances of success, as discussed in this report.

Collie eye anomaly in a mixed-breed dog.

A 5-year-old, mixed-breed dog was presented for tetraparesis. Neurologic alterations included a decreased menace response in both eyes. Therefore, an ophthalmic examination was requested. The dog was visual, but menace response, dazzle and pupillary light reflexes were reduced bilaterally. Indirect ophthalmoscopy revealed bilateral optic nerve coloboma and severe choroidal hypoplasia. These lesions closely resembled the ophthalmoscopic features of Collie eye anomaly (CEA). In spite of treatment, the dog's condition worsened and the animal was therefore euthanized. Histology of the globes confirmed severe choroidal hypoplasia and optic disc coloboma in both eyes. The dog was diagnosed to have a lymphoma involving the spinal cord. The two entities were considered not related. As only moderate sight impairment was caused by the posterior segment anomalies, it is by chance that these lesions resembling CEA were found in this mixed-breed dog.