Progressive ulcerative keratitis in dogs in the United Kingdom: Microbial isolates, antimicrobial sensitivity, and resistance patterns.

OBJECTIVES: The objective of the study was to identify bacterial pathogens and their antimicrobial sensitivity profile associated with cases of canine progressive ulcerative keratitis. MATERIALS AND METHODS: Analysis of microbial culture and sensitivity results from dogs with progressive ulcerative keratitis presenting to a UK referral practice between December 2018 and August 2020. RESULTS: Positive bacterial cultures were obtained from 80/148 (54%) of the canine ulcers sampled with 99 bacterial isolates cultured. Streptococcus canis (n = 29), Pseudomonas aeruginosa (n = 19), and Staphylococcus pseudintermedius (n = 16) were the most common isolates. Pseudomonas aeruginosa was more likely to be isolated whether the ulcer was clinically malacic at the time of sampling (OR = 10.1, p < .001). Ulcers treated prior to culture with fusidic acid were 7.6 times more likely to be positive than those treated with any other antimicrobial(s). Bacterial isolates demonstrated resistance against neomycin (85%), fusidic acid (78%), and tetracycline (68%). Conversely, isolates were most likely to be sensitive to gentamicin (88%), ofloxacin (77%), ciprofloxacin (73%), and chloramphenicol (64%). Antimicrobial combinations of chloramphenicol or gentamicin with a fluoroquinolone (ofloxacin or ciprofloxacin) or chloramphenicol combined with gentamicin were the most effective on in vitro analysis (over 90% susceptibility of all isolates). CONCLUSION: The most common bacterial species associated with canine progressive ulcerative keratitis in a UK referral population were S. canis, P. aeruginosa, and S. pseudintermedius. Combination antimicrobial therapy is recommended pending culture and sensitivity results given the varied antimicrobial susceptibility profiles and significant bacterial in vitro resistance to antimicrobial monotherapy.

Estimation of the intraoperative blood loss in dogs undergoing enucleation.

PURPOSE: To quantify the surgical blood loss during canine enucleation and to investigate the relationship between this and any patient, surgical, and anesthetic factors. METHODS: A prospective observational analysis was conducted on 121 client-owned dogs (130 eyes) undergoing enucleation at a referral ophthalmology clinic. Blood loss was estimated by the gravimetric method (weight difference between dry and blood-containing surgical materials) to provide absolute blood loss (ABL) in milliliters, expressed as a percentage of circulating blood volume, to establish relative blood loss (RBL). RESULTS: Median ABL was 12 ml (1.6-116 ml), and median RBL was 1.3% (0.1%-6.7%). A higher RBL was associated with the following: use of a bupivacaine splash block versus retrobulbar nerve block (1.9 vs. 1%; p < .001), transpalpebral versus subconjunctival approach (2.2 vs. 1.3%; p = .003), and small versus large breed dogs (1.7% vs. 1.1%; p = .001). Both ABL and RBL differed significantly between surgeons. There was no significant difference in hemorrhage associated with the presence of ocular hypertension, systemic illness, surgical time, administration of meloxicam or choice of pre-medicant (acepromazine vs medetomidine). No dog required supportive intervention in response to surgical hemorrhage. CONCLUSIONS: This study has established a surgical blood loss estimate for dogs undergoing enucleation at an ophthalmology referral centre. Subconjunctival enucleation may be preferred for patients at greater risk of haemodynamic complications.

Incidence and risk factors for surgical glove perforation in small animal ophthalmic surgery.

OBJECTIVE: To determine the incidence of perforation of surgical gloves and identify associated risk factors that contribute to glove perforation in small animal ophthalmic surgery. STUDY DESIGN: Observational cohort study. SAMPLE POPULATION: Surgical gloves (n = 2000) collected following 765 small animal ophthalmic procedures. METHODS: All the gloves were tested for perforation at the end of the procedure using a water leak test. The potential risk factors for glove perforation were recorded, and associations between these risk factors and perforation were explored using univariable (Fisher's exact test) and mixed effect logistic regression analysis. Results were considered significant if P < .05. RESULTS: Glove perforation was detected in 6% of procedures. Glove perforation was 1.97 (95% CI: 0.98-4.22) times more likely in extraocular than in intraocular surgeries (7.3% vs 3.9%; P = .0462). The incidence of perforations was not statistically different between main and assistant surgeon (P = .86). No significant association was found between the risk of glove perforation and duration of the procedure (P = .13). Perforation of the nondominant hand was 2.6 (95% CI: 1.38-4.98) times more likely than the dominant hand (74% vs 26%; P = .0028). Only 22% of the perforations were detected intraoperatively. Multivariable analysis identified only extraocular surgery as a risk factor for perforations. CONCLUSIONS: There is a low incidence of glove perforation in small animal ophthalmic surgery, but extra care of the nondominant hand is required, especially during extraocular procedures.

An investigation into the bacterial contamination of goniolenses in use in clinical practice.

Objectives To report the incidence and evaluate the clinical significance of goniolens bacterial contamination in clinical use in dogs with three different usage protocols and one with an added cleaning protocol. Animals Studied and Methods Three groups of twenty dogs undergoing gonioscopy at a private practice in the UK had the goniolenses swabbed for bacteriology culture and identification prior to placement on the cornea. Three protocols of lens use, with 2 different types of goniolens, were studied. One protocol was then repeated with 21 dogs with a lens cleaning protocol prior to storage. Results Low levels of bacterial contamination were found in all 3 initial groups (10-15%). No correlation was found between usage protocol used and rate of contamination and no correlation was found between length of storage between use and contamination. All bacteria cultured were considered naturally occurring commensals for the canine eye and environment. The group with a cleaning protocol had a 4.7% contamination rate. This was not statistically different from the non-cleaning groups. Conclusions The rate of bacterial contamination of goniolenses in clinical practice is low and the bacterial contaminants consist of commensal bacteria, unlikely to be of detriment to the eye. Minimal contamination of the goniolenses was found and this did not appear to be of clinical significance. The introduction of a simple cleaning protocol did not produce a statistically significant reduction in bacterial contamination.

Uveal cysts in domestic cats: a retrospective evaluation of thirty-six cases.

OBJECTIVE: The aim of this retrospective study was to investigate uveal cysts in domestic cats by identifying prevalence, predispositions, location, presumed etiologies, and sequelae. ANIMALS STUDIED: The clinical databases of two referral hospitals (The Animal Health Trust in the UK and Animal Eye Care in Australia) were searched to identify cats that had been diagnosed with uveal cysts, either as an incidental finding or as the reason for referral. Thirty-six cases were found. PROCEDURES: The signalment of the patients was recorded, along with any relevant previous clinical history, treatment, follow-up, and sequela. The data were compared with the unaffected feline populations examined by ophthalmologists in the two hospitals over the same 10-year time period. RESULTS: Thirty-six cats were affected, from a total examined population of 5017 (prevalence 0.72%). Twenty-one of the 36 cats were Burmese. The two centers examined 516 Burmese cats in the same time period, giving an incidence in Burmese cats of 4.1%. The mean age of affected cats at presentation was 10.25 years (SD = 4.12 years), and female cats accounted for 23 of 36 of the cases. Only 2 of 36 cats had concurrent intraocular disease. CONCLUSIONS: Uveal cysts in domestic cats are rare ophthalmic findings, and in most cases, they do not cause any clinical problems The Burmese breed is overrepresented in the data, with a relatively high prevalence of uveal cysts.

IMAGING DIAGNOSIS - UNILATERAL TRIGEMINAL NEURITIS MIMICKING PERIPHERAL NERVE SHEATH TUMOR IN A HORSE.

A 16-year old Warmblood gelding presented with a nonhealing corneal ulcer and absent corneal sensation in the left eye. A lesion affecting the maxillary and ophthalmic branches of the left trigeminal nerve was suspected. Magnetic resonance (MR) imaging identified marked thickening of the ophthalmic and maxillary branches of the left trigeminal nerve. The nerve was iso- to hypointense on T1-weighted and T2-weighted images with heterogeneous enhancement. A peripheral nerve sheath tumor was suspected, however granulomatous neuritis was histopathologically confirmed. These inflammatory changes can result in severe nerve enlargement and should be considered with MR findings suggestive of peripheral nerve sheath tumor.

Surgical management and outcome of lower eyelid entropion in 124 cats.

OBJECTIVES: To evaluate the success rate of various surgical techniques for the management of lower eyelid entropion in cats. DESIGN: Retrospective study. Animals studied One hundred and twenty-four cats with surgical correction of lower eyelid entropion of 200 eyes over a 13 year period. METHODS: Records of 124 cats were reviewed for signalment, type of entropion, surgical procedure performed and post-operative result. RESULTS: Combinations of the Hotz-Celsus (HC), lateral canthal closure and full thickness wedge resection techniques were used to treat 64 bilateral and 60 unilateral cases of lower lid entropion. Twenty-three cats were under a year of age, 52 cats were aged between 2 and 8 years and 49 were over 8 years old. The overall success rate for a single surgical procedure (which may consist of multiple techniques) to correct lower eyelid entropion was 96.0% per eye. The remaining 4.0% had the entropion resolved with a second surgery. A combined HC and lateral canthal closure had a 99.21% success rate of resolving lower lid entropion. Geriatric cats were the most likely age group to develop corneal sequestra; 37% of cats in this group presented with entropion and corneal sequestra concurrently. Seventeen percent of cats that presented with unilateral entropion and did not have prophylactic surgery on the fellow eye went on to develop entropion in the fellow eye. CONCLUSIONS: A combined HC and lateral canthal closure was the most effective surgical technique in managing lower eyelid entropion of cats in our study. Prophylactic lateral canthal closure in the unaffected eye is recommended.

Lower lid entropion in dogs: A modified technique of the combined Hotz-Celsus and wedge resection procedure.

BACKGROUND: This study aimed to describe a modification of the combined Hotz-Celsus and wedge resection technique for the treatment of lower lid entropion in dogs and evaluate its success rate. METHODS: To reduce tissue trauma, facilitate tissue handling and shorten the surgical time, shortening of the eyelid was performed by excising a rectangular piece of the eyelid margin only, in the central section, extending to but not below the first Hotz-Celsus incision. The eyelid margin surgical wound was then sutured before excision of the Hotz-Celsus crescent which had been surgically scored at the start of surgery. Records of 31 dogs were reviewed for signalment, outcome, need for further surgery, and follow up from 6 to 48 months after surgery. RESULTS: Sixty-one eyes with lower lid entropion were treated. The most common breeds were English bulldog and English cocker spaniel and the median age was 16 months. The success rate for a single entropion correction surgery was 98.4%. One eyelid required a second surgical correction and four eyelids of three large breed dogs had wound breakdown. CONCLUSIONS: This modified technique is successful at correcting lower eyelid entropion associated with overlong eyelid length in dogs while being technically easier to perform.

Repair of a scleral defect with an autogenous fascia lata graft in a dog.

A case of a traumatic scleral rupture with uveal herniation in a dog was treated with an autogenous fascia lata graft. Placement of the graft resolved the uveal prolapse and resulted in return of strength and a more normal structure. Fascia lata appears to be an effective scaffolding graft for the repair of scleral defects. It is cheap, easily harvested and large grafts may be obtained. Healing was rapid and the end result was a cosmetic, comfortable, fully functional eye.

Schirmer tear tests and intraocular pressures in conscious and anesthetized koalas (Phascolarctus cinereus).

OBJECTIVE: To estimate mean Schirmer tear test (STT) and intraocular pressure (IOP) values in healthy koalas both conscious and anesthetized. METHODS: Data were gathered from koalas in Victoria, Australia. Conscious examinations were performed on captive koalas. Free-ranging (wild) koalas were examined under anesthesia. Anesthesia was induced using alfaxalone, and animals were maintained on oxygen and isoflurane if required. All animals were healthy and had no surface ocular pathology detectable during slit lamp biomicroscopy. STT I tests were performed using commercial STT test strips placed in the lower fornix for 1 min. IOP was measured using an applanation tonometer after topical anesthesia. The higher value of the two eyes for both STT and IOP was analyzed. STT was measured in 53 koalas (34 conscious, 19 anesthetized) and IOP was measured in 43 koalas (30 conscious, 13 anesthetized). A two-sample t-test was used to compare means. A P-value <0.05 was regarded as significant. Mean ± SD is presented. RESULTS: The mean higher STT in conscious koalas was 10.3 ± 3.6 mm wetting/min and in anesthetized koalas it decreased to 3.8 ± 4.0 mm wetting/min (P < 0.0001). The mean higher IOP in conscious koalas was 15.3 ± 5.1 mmHg, and in anesthetized koalas it was 13.8 ± 3.4 mmHg (P = 0.32). There was no effect of sex on either STT or IOP. CONCLUSIONS: The mean and SD of STT and IOP values for koalas both conscious and anesthetized were reported. The mean STT was significantly reduced by alfaxalone anesthesia.

Keratomycosis in a dog treated with topical 1% voriconazole solution.

A 2-year-old Jack Russell Terrier was presented for treatment of a worsening corneal ulcer and keratomalacia following removal of a vegetative foreign body. The keratomalacia responded to topical gentamicin therapy; however, the eye became suddenly painful and at examination two areas of increased opacity had developed. Fungal keratitis was demonstrated by corneal scrape showing branching, septate fungal hyphae. Treatment with 1% voriconazole was effective in resolving the keratomycosis.

The prevalence of uveitis in a population of donkeys in the UK.

BACKGROUND: Uveitis is reported to be a leading cause of blindness in horses. Little work has been undertaken to date to investigate whether donkeys are affected by a similar disease prevalence. OBJECTIVES: To investigate the disease prevalence of uveitis in a population of donkeys in the UK. STUDY DESIGN: Descriptive observational study. METHODS: An ophthalmic examination was performed on each donkey, in a darkened stable. Each donkey underwent slit lamp biomicroscopy, and direct and/or indirect ophthalmoscopy. Fluorescein staining, STT1 and IOPs were measured when deemed clinically necessary. Pharmacological pupillary dilation was achieved using 1% tropicamide. RESULTS: A total of 207 donkeys were examined: 139 males (67.1%) and 68 females (32.9%). Age range was 2-37 years (median: 17 years, interquartile range: 9-25 years). Three donkeys (1.5%) were blind in one eye, and one was monocular at the time of examination. Signs consistent with either previous or current uveitis were identified in eight eyes of six animals (2.9%). Clinical signs included are as follows: miosis (n = 1), corpora nigra atrophy (n = 6), anterior lens capsule pigment (n = 2), cataract (n = 8), posterior synechiae (n = 3), lens subluxation (n = 1), vitreal changes (n = 2), peripapillary scarring (n = 3) and phthisis bulbi (n = 1). Significant ocular pathology precluded fundic examination in three eyes. Three out of eight eyes (37.5%) were blinded by the pathology. The risk of uveitis was found to increase with age (OR 1.1, CI: 1.01-1.25) on univariable analysis (P = .046.). MAIN LIMITATIONS: Fluorescein staining, tonometry and Schirmer tear test measurements were not performed on all donkeys. CONCLUSIONS: The disease prevalence reported here is comparable to that reported for horses in the UK. Larger prospective studies are necessary to determine whether there is a similar trend in disease prevalence in the donkey population worldwide. In addition, further investigations should aim to establish whether uveitis in donkeys is similar to the ERU syndrome seen in horses.