Clinical and pathological findings in five dogs with nodular histiocytic iritis in the United Kingdom: A case series.

PURPOSE: The aim of this study was to describe the clinical presentation, histopathology, management, and outcome of nodular histiocytic iritis, an intraocular variant of nodular granulomatous episcleritis (NGE). METHODS: A retrospective review of the medical records of five dogs with intraocular NGE-type inflammation as diagnosed by histopathology. RESULTS: Four Border Collies and one crossbreed dog, aged 1.5-3.4 years (mean age 2.38 years). The clinical presentation was an extensive, raised, pale iris lesion of variable location. All cases were unilateral. The physical examination was normal. Complete blood count/serum biochemistry (n = 1) and thoracic radiography (n = 1) were normal. Ocular ultrasound (n = 2) was normal apart from increased iris thickness. Enucleation (n = 4) or excisional biopsy (iridectomy, n = 1) was performed because of suspected neoplasia. Following enucleation, the remaining, contralateral eye did not develop additional lesions (9 days-3.7 years follow-up). There was no recurrence following sector iridectomy with 5 months topical 1% prednisolone acetate (3.9 years follow-up). The histopathologic findings in all five cases indicated a focal histiocytic and lymphoplasmacytic anterior uveitis (iritis), similar to that seen in cases of NGE. CONCLUSION: Nodular histiocytic iritis presents as unilateral iris thickening in isolation and young Collies appear to be predisposed. The histopathological findings are similar to NGE. Although the clinical presentation resembles intraocular neoplasia, an inflammatory process should be considered, which may be amenable to medical management. Definitive diagnosis may be obtained by iris sampling.

Iris biopsy to investigate feline iris hyperpigmentation.

OBJECTIVE: To evaluate the benefit of iris biopsy in cats with iris hyperpigmentation to differentiate melanosis from early feline diffuse iris melanoma (FDIM). METHODS: The medical records of cats with unilateral iris hyperpigmentation that had undergone iris biopsy between February 2013 and September 2016 at Willows Veterinary Centre & Referral Service were reviewed. RESULTS: Seven cats with unilateral iris hyperpigmentation were included in this retrospective study. The biopsy procedure was performed under general anesthesia (n = 7) with neuromuscular blockade (n = 6) following pre-operative topical miotic therapy (n = 5). One to six biopsy samples per eye were harvested from areas of hyperpigmentation. The samples were partial thickness (n = 4 eyes) and full thickness (n = 3 eyes). Complications were minor: mild intra-operative hemorrhage (n = 4), fibrin clot (n = 2), corneal ulcer (n = 1), post-operative ocular hypertension (n = 1), dyscoria (n = 1), and pseudopolycoria (n = 2). The first biopsy was diagnostic in six cats; a repeat biopsy was necessary in one cat. Histopathology was consistent with melanosis in five cats and with early FDIM in two cats. Screening for signs of metastatic disease (thoracic computed tomography and abdominal ultrasonography) was negative in the two cats with a preliminary diagnosis of early FDIM. Subsequent enucleation and histopathology confirmed the initial diagnosis in both cases. CONCLUSIONS: Iris biopsy in cats with iris hyperpigmentation can be beneficial to differentiate melanosis from early FDIM and thereby help to justify the decision for early enucleation.

Bilateral third eyelid ectopic cilia in an adult horse.

A 15-year-old Cob mare presented with a 4-month history of chronic epiphora and intermittent blepharospasm in the right eye. On ophthalmic examination, two translucent aberrant hairs were identified at the third eyelid margin corresponding to an area of corneal fibrosis and neovascularization. Partial excision of the third eyelid was performed, and histopathology confirmed ectopic hair follicles. Two weeks later, clinical signs recurred in the same eye. Examination revealed another pair of aberrant hairs on the bulbar surface of the third eyelid near its leading edge. This portion of the third eyelid was also excised, and histopathology confirmed two additional ectopic hair follicles. Eight months later, the horse developed similar clinical signs in the left eye. Ophthalmic examination showed a single aberrant translucent hair at the third eyelid margin associated with focal fibrosis and neovascularization of the ventromedial cornea. Partial excision of the third eyelid was performed, and histopathology confirmed an ectopic hair follicle within the third eyelid conjunctiva. Excision was curative at 4 years postoperatively with no further recurrence in either eye.

Vernal-like conjunctivitis in a western lowland gorilla (Gorilla gorilla gorilla).

CASE DESCRIPTION: A 17-year-old female western lowland gorilla presented with bilateral ocular discharge, conjunctivitis, and rhinitis that was investigated and treated over a 34-month period. Clinical findings, diagnostic results, treatment, and follow-up are described. CLINICAL FINDING: A mild intermittent mucoid ocular discharge was initially noted. 10 months later, conjunctival hyperemia and thickening developed and progressed rapidly to a mass-like lesion covering the right eye. Hematology revealed eosinophilia. Conjunctival cytology revealed eosinophils and neutrophils, and histopathology revealed a chronic proliferative eosinophilic conjunctivitis. 21 months after, the ocular lesions were investigated the gorilla developed masses within both external nares. Histopathology of the nasal lesions revealed chronic-active eosinophilic rhinitis. TREATMENT AND OUTCOME: Treatment of the gorilla was based on protocols recommended for human patients. Protocols for mild, moderate, and finally severe disease were used, involving topical and oral combinations of treatments. The gorilla eventually responded to systemic immunosuppressant therapy recommended for severe refractory disease. CLINICAL SIGNIFICANCE: To the authors' knowledge, this is the first reported case of vernal-like conjunctivitis in a western lowland gorilla.

Ocular biometry by computed tomography in different dog breeds.

OBJECTIVE: To (i) correlate B-mode ocular ultrasound (US) and computed tomography (CT) (prospective pilot study), (ii) establish a reliable method to measure the normal canine eye using CT, (iii) establish a reference guide for some dog breeds, (iv) compare eye size between different breeds and breed groups, and (v) investigate the correlation between eye dimensions and body weight, gender, and skull type (retrospective study). PROCEDURE: B-mode US and CT were performed on ten sheep cadaveric eyes. CT biometry involved 100 adult pure-bred dogs with nonocular and nonorbital disease, representing eleven breeds. Eye length, width, and height were each measured in two of three planes (horizontal, sagittal, and equatorial). RESULTS: B-mode US and CT measurements of sheep cadaveric eyes correlated well (0.70-0.71). The shape of the canine eye was found to be akin to an oblate spheroid (a flattened sphere). A reference guide was established for eleven breeds. Eyes of large breed dogs were significantly larger than those of medium and small breed dogs (P < 0.01), and eyes of medium breed dogs were significantly larger than those of small breed dogs (P < 0.01). Eye size correlated with body weight (0.74-0.82) but not gender or skull type. CONCLUSIONS: Computed tomography is a suitable method for biometry of the canine eye, and a reference guide was established for eleven breeds. Eye size correlated with breed size and body weight. Because correlation between B-mode US and CT was shown, the obtained values can be applied in the clinical setting, for example, for the diagnosis of microphthalmos and buphthalmos.

Outcome of phacoemulsification following corneal and lens laceration in cats and dogs (2000-2010).

OBJECTIVE: To investigate the success rate of phacoemulsification following corneal and lens laceration in dogs and cats. PROCEDURE: Retrospective review of cats and dogs presenting with corneal and lens laceration and treated with phacoemulsification. RESULTS: The records of 33 patients (33 eyes: six feline, 27 canine) presenting to a private referral center were reviewed. Affected dogs were younger (median 18 months) than affected cats (median 30 months). The lacerations were caused by cat scratch trauma (9/33), thorn injury (6/33), and glass shards (1/33); the cause was unknown in 17/33 cases. All cats and 85.2% of all dogs were visual at the last examination. The median follow-up was 4 and 8 months for cats and dogs, respectively. In all canine cases that developed vision loss, this occurred within the first 14 weeks postoperatively. The ultimate cause for vision loss in dogs was secondary glaucoma (4/4) and retinal detachment (1/4). CONCLUSION: Cats have an excellent outcome and dogs a very good outcome following surgery for corneal and lens laceration. The cause of the trauma, the size of the lesion, the time interval between the ocular trauma and surgery, and the type of surgery were not found to have an influence on the outcome of patients in this study. We postulate that vision loss might develop more often in cases with complications associated with the initial corneal laceration wound.

Equine conjunctival haemangiosarcoma: Clinical presentation, management, and outcome of seven cases in the United Kingdom.

Background: Only 27 cases of equine conjunctival haemangiosarcoma have been reported in the literature over the past 37 years. Out of these, 22% of cases were lost to follow-up, 52% were euthanized, and 26% survived. A scarcity of cases and information is available for this rarely seen conjunctival tumour. Aim: To describe the clinical features, management, and outcome of conjunctival hemangiosarcoma in seven horses in the UK. Methods: Optivet medical records were reviewed for equine cases seen or advised on with a histopathological diagnosis of conjunctival haemangiosarcoma between January 2013 and March 2023. Medical records were accessed for details of signalment, history, management, and follow-up. Histopathology was used to confirm the diagnosis of haemangiosarcoma and assess the surgical margins. Immunohistochemistry was performed in a minority of cases with poorly differentiated solid tumours to support vascular lineage. Results: Seven eyes from seven horses (five geldings and two mares) with a mean age of 16 years and median of 18 years (range 10-21 years) met the criteria. Serosanguinous discharge was seen in six eyes. All eyes were managed surgically; 4 by exenteration and 3 by conjunctivectomy/keratectomy. Adjunctive cryotherapy was performed in two eyes. Metastatic disease in the ipsilateral parotid salivary gland, confirmed with histopathology, was seen in one horse. Surgical margins were clear in all but one eye. Solar elastosis was noted in five eyes. All horses were healthy at the last follow-up (0.2-5 years, mean 2.9 years, and median 2 years). Conclusion: Equine conjunctival haemangiosarcoma is rare. Serosanguinous ocular discharge is a common clinical sign. Early surgical excision is highly effective. Solar elastosis is a common histopathological feature, suggesting a role for UV-light in the pathogenesis.

Parotid duct transposition in dogs: a retrospective review of 92 eyes from 1999 to 2009.

OBJECTIVE: The aim of this study was to perform a retrospective review of parotid duct transposition (PDT) in the dog to determine the rate and nature of complications, the success and failure rates and to evaluate owner satisfaction. METHODS: Medical records of 56 dogs (92 eyes) that underwent PDT and subsequent follow-up by a veterinary ophthalmologist were reviewed. Forty owners (40 dogs/66 eyes) were contacted by telephone and 37 owners (37 dogs/60 eyes) also completed a visual analog scale questionnaire. Statistical evaluation included Wilcoxon Signed Rank tests, one-way analysis of variance and Kaplan-Meier survival analysis with Wilcoxon and Log-rank tests. RESULTS: The mean follow-up was 38.7 months (range 1-109 months). The surgical success rate was 92% (85/92 eyes). Total failures (8%, 7/92 eyes) were because of severe saliva intolerance (n = 5 eyes) and PDT failure (n = 2 eyes). The complication rate was 50% (46/92 eyes) of which 61% (28/46 eyes) were managed medically and 39% (18/46 eyes) required further surgery. Ninety percent (36/40) of owners indicated that they would proceed with surgery again. Statistically significant improvements in owner perception of ocular comfort, number of daily topical treatments, ocular wetness, and postoperative vision were identified. CONCLUSIONS: This study shows that PDT is a successful procedure based on clinical findings and in terms of owner perception. It has also demonstrated that PDT improves ocular comfort and vision in medically refractive cases of keratoconjunctivitis sicca, and that a low level of on-going management is required in 33% of cases.

Cataracts are not associated with retinal detachment in the Bichon Frise in the UK--a retrospective study of preoperative findings and outcomes in 40 eyes.

OBJECTIVE: The aim of this study was to evaluate whether the Bichon Frise population in the UK is at the same risk of developing retinal detachment in association with cataract formation and following phacoemulsification as described in reports from the USA. PROCEDURES: The medical records of Bichon Frises which were presented for cataract assessment and of those which were treated with phacoemulsification at Willows Referral Service between 1997 and 2009 were reviewed. RESULTS: Forty eyes (26 dogs) with unilateral or bilateral cataracts were included in the study. There was no evidence of retinal detachment associated with the cataracts at initial presentation. Phacoemulsification was performed on 34 eyes (20 dogs). Clinically evident lens-induced uveitis was treated preoperatively in 17/34 eyes. Artificial lens implantation was carried out in 30/34 eyes; automated anterior vitrectomy was performed in 7/34 eyes. The mean follow-up time was 16.6 months (range 1.5-73 months). At the last re-examination, 31/34 eyes (91.2%) were visual. Three eyes (8.8%) were blind--two (in the same dog) because of presumptive bilateral optic nerve disease and one because of uveitis and secondary glaucoma. There was no evidence of retinal detachment following phacoemulsification in any of the 34 eyes. CONCLUSION: This study suggests that the Bichon Frise population in the UK does not appear to have a predisposition for retinal detachment in association with cataract formation or following cataract surgery. Prophylactic random transscleral laser retinopexy or transscleral cryopexy cannot therefore be routinely recommended for Bichon Frises with cataracts in the UK.

Surveying veterinary ophthalmologists to assess the advice given to owners of pets with irreversible blindness.

BACKGROUND: The primary purpose of this survey was to determine how veterinary ophthalmologists manage cases of irreversible blindness and to report the most common causes of blindness. METHODS: Respondents completed a questionnaire sent by email with the cooperation of the American College of Veterinary Ophthalmologists, the European College of Veterinary Ophthalmologists and the Latin American College of Veterinary Ophthalmologists. The questionnaire was developed containing 12 questions with both open and closed multiple-choice response options. RESULTS: One hundred and eight veterinary ophthalmologists answered the questionnaire. Of the respondents, 83 per cent had graduated for more than 10 years. Glaucoma (63.56 per cent) was the main cited cause of blindness, followed by progressive retinal atrophy (PRA) (17.80 per cent) and retinal detachment (6.78 per cent). The major concerns of owners refer to the impact of blindness on quality-of-life, (39.31 per cent), followed by depression and anxiety (20 per cent), and environment adaptation (11.72 per cent). General recommendations include avoidance of changes in the domestic environment (18.45 per cent), use of auditory stimulation (14.09 per cent) and avoidance of dangerous areas (12.75 per cent). Almost 31 per cent of professionals do not recommend the use of literature on how to deal with blind pets. CONCLUSIONS: The survey determined glaucoma and PRA as the most common causes of irreversible blindness in pets. Several recommendations that are frequently given to owners of blind pets are presented.

Efficacy of lamellar resection, cryotherapy, and adjunctive grafting for the treatment of canine limbal melanoma.

OBJECTIVE: To evaluate the efficacy and complication rate of partial lamellar resection followed by cryotherapy for the management of canine limbal melanoma. ANIMALS STUDIED: Fourteen dogs with unilateral canine limbal melanoma which were managed surgically by partial lamellar resection, cryotherapy (1,1,1,2-tetrafluoroethane) and an adjunctive graft procedure. METHODS: The clinical records of dogs treated between June 1998 and June 2008 were reviewed. The signalment, approximate size and location of the melanoma, variation in surgical technique, recurrence rate, short-term (< three months) and long-term (> three months) complications were assessed. Follow-up information was collected by patient re-examination or telephone interview. RESULTS: The mean age at diagnosis was 6.3 years, with a range from 3.2 to 12 years. Seven breeds were affected, including five cross-breed dogs and four Golden Retrievers. The tumour involved the dorsal arc (from the dorsomedial to the ventrolateral quadrant) in 12 eyes and the ventral arc in two eyes. The size of the tumour ranged from 30 to 180 degrees of the limbal circumference. A double freeze-thaw cycle of cryotherapy was performed in 7/14 eyes and a triple freeze-thaw cycle in 7/14 eyes. An adjunctive conjunctival graft was performed in 13/14 eyes (free graft n = 3, posterior nictitans conjunctiva/cartilage n = 4, advancement graft n = 5, small intestinal submucosa/advancement graft n = 1) and a frozen homologous graft in 1/14 eyes. The duration of follow-up ranged from 6 months to 8.5 years with a median of 2.1 years. Recurrence was not clinically detected in any of the 14 eyes. Early complications occurred in 8/14 eyes and included anterior uveitis (7/14), corneal ulceration (5/14), marked corneal granulation tissue at the graft margin (2/14), dyscoria (2/14), corneal lipidosis (1/14) and corneal oedema (1/14). Intra-operative globe perforation had occurred in 5/7 eyes with anterior uveitis and 2/2 eyes with transient dyscoria. Late complications occurred in 3/14 eyes and included corneal lipidosis which was either mild (< 2mm in diameter, 1/14) or marked (>1cm in diameter, 2/14). Marked lipidosis only occurred following the treatment of extensive limbal melanomas which involved approximately 50% of the limbal circumference. CONCLUSIONS: Surgical management comprising partial lamellar resection, cryotherapy and adjunctive graft placement is technically straightforward, minimally invasive, well tolerated and highly effective. Marked corneal lipidosis is most likely to occur as a post-operative complication when the limbal melanoma is extensive.

Cataract in the UK Leonberger population.

OBJECTIVE: To survey the Leonberger, a numerically small breed in the UK, for the presence of cataract and find statistical support for the possible presence of inherited forms of cataract. METHODS: Ocular examinations were carried out by the first author between September 1996 and September 1998 on 211 Leonbergers; results of the ocular examination of further 228 Leonbergers examined between January 1990 and September 1998 by members of the British Veterinary Association/KC/ISDS eye scheme (BVA/KC/ISDS eye scheme) panel were analyzed. Data from all dogs examined were pooled in a composite database of 365 Leonbergers and the relationships between offspring and parents for the identified forms of cataract were examined with appropriate statistical methods. RESULTS: Cataracts were diagnosed in 90 Leonbergers, the majority being nuclear (40) or posterior polar subcapsular (31). A subgroup of nuclear cataracts, diagnosed in 11 dogs, is described and named as 'posterior nuclear cataract.' For posterior polar cataract, a positive association between offspring and parents was made in the logistic regression model, supporting the suggestion of inheritance. CONCLUSIONS: The presence of several types of cataract in the UK Leonberger population is described. Statistical support for the inheritance of posterior polar subcapsular cataract is given.

Feline corneal sequestra: a review of 64 cases (80 eyes) from 1993 to 2000.

Feline corneal sequestrum is a common condition of the feline cornea. The purpose of this study was to provide a detailed description of the clinical features of the condition including the response to different management options and to assess the rate of recurrence. The medical records of 64 cases (80 eyes) of feline corneal sequestra that presented to the Animal Health Trust from 1993 to 2000 were reviewed. Fifty-two cases were reviewed retrospectively; 12 cases were assessed prospectively between April and September 2000 as part of a separate study. The Persian was the most frequently encountered breed and the mean age of affected cats was 5.6 years. At initial presentation, sequestra were unilateral in 58 cats and bilateral in 6 cats, 5 of which were Persians. Ocular discomfort and ocular discharge were common presenting signs, occurring in 42 and 36 eyes, respectively. Seventy-four eyes were managed surgically with keratectomy only (n = 44) or keratectomy followed by a graft procedure (n = 30). Sequestra recurred in 16 eyes in the study. There was no significant difference in the rate of recurrence between eyes that received a graft procedure (n = 5) and eyes that did not (n = 11) (P = 0.56). Complications following transection of conjunctival pedicle grafts were observed. Brown to black discoloration of noncorneal tissue and therapeutic biomaterials was observed, including discoloration of both viable and apparently nonviable grafted conjunctival tissue, small intestinal submucosa graft material and bandage contact lenses.

Feline corneal sequestrum: laboratory analysis of ocular samples from 12 cats.

Feline corneal sequestrum is a common ocular condition typified by brown to black discoloration of the cornea. The nature of the discoloration has not been identified. The purpose of this study was to perform a laboratory investigation of ocular samples from 12 clinical cases of feline corneal sequestrum in an attempt to characterize the nature of the discoloration. The 12 cases were referred to the Ophthalmology Unit at the Animal Health Trust between April and September 2000, and were also part of a clinical review of 64 cases of feline corneal sequestrum described separately. Five laboratory techniques that are routinely performed at the Biomaterials Unit, Aston University were employed for analysis of the ocular samples. Ocular material included corneal sequestrum, tear samples, meibomian gland secretions, and bandage contact lenses from the 12 clinical cases. High-performance liquid chromatography data showed that total tear lipid in affected eyes was significantly lower than in control eyes (P = 0.016); total tear lipid in affected eyes was lower than in the unaffected, contralateral eyes of the same cat but the difference was not significant (P = 0.29). The presence of an unknown lipid class was observed in tears and meibomian secretions of affected, contralateral and control eyes. Scanning electron microscopy showed that the discoloration in affected corneas was not due to the presence of iron. Fluorescence spectroscopic analysis of sequestra, unaffected corneas and contact lenses (from affected and contralateral/unaffected eyes) showed that lipid and protein were present but did not play an important role in sequestra. Ultraviolet-visible light absorbance spectroscopy revealed a peak at 385 nm in unaffected corneas that was absent in sequestra and the difference was significant (P < 0.0001); this peak may be a characteristic feature of the normal feline cornea. The absorbance spectra displayed a peak at 280 nm in two sequestra suggesting that chromophore groups (e.g. melanin) were present. Optical microscopy performed on 10 sequestra revealed the presence of particles, which were consistent with the appearance of melanin particles, providing laboratory evidence that characterized the nature of the discoloration as melanin for the first time.