Thomson S.M.,Davies Veterinary Specialists |
Oliver J.A.,Unit of Comparative Ophthalmology |
Gould D.J.,Davies Veterinary Specialists |
Mendl M.,University of Bristol |
Leece E.A.,Dick White Referrals
Veterinary Anaesthesia and Analgesia | Year: 2013
Objective: To perform preliminary evaluations into the ocular analgesic effect of topical 1% morphine in a clinical setting and to determine onset, duration and complications. Study design: Prospective, randomised, blinded clinical study. Animals: Twenty six dogs and seventeen cats, all client-owned. Methods: Dogs and cats with corneal ulceration requiring medical treatment or corneal conditions requiring surgery were included and randomly assigned to receive one drop of topical morphine (group M) or base solution (group B). Recordings were made prior to application and at 5, 10, 20, 30, 40, 50 and 60 minutes, then 2, 3, 4, 5 and 6 hours. Corneal aesthesiometry, blink rates and scores for blepharospasm (BLEPH), conjunctival hyperaemia (CH) and lacrimation (LAC) were recorded. Statistical analyses used anova, t-tests and Mann-Whitney U tests as relevant. Results: No significant effect of treatment group on any recordings was found at any time point in either dogs or cats. Adverse effects of increased BLEPH, CH or blink rate were observed in six animals (three cats from group M and three dogs from group B), occurring within 5 minutes of drop application and lasting for between 10 minutes and 6 hours. Conclusions and clinical relevance: Topical ocular morphine showed no measurable analgesic effect against corneal pain in dogs and cats. © 2013 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.
Matas Riera M.,Lane College |
Donaldson D.,Unit of Comparative Ophthalmology |
Priestnall S.L.,Lane College
Veterinary ophthalmology | Year: 2015
The aim of this article was to describe Descemet's membrane detachment (DMD) following phacoemulsification in five equine eyes and to review the human literature on this topic. In the last decade, there has been increased reporting of DMD in the human literature, in particular following cataract surgery. The natural history of DMD remains unknown and although various medical and surgical treatments have been advocated there is no recognized 'gold standard' treatment for DMD. This case series reports the diagnosis of DMD in four horses (5 eyes) in association with phacoemulsification surgery. The diagnosis of DMD in these patients was made intra-operatively, postoperatively or on subsequent histopathological examination. The surgical reports, photographic or video recordings, and ultrasound data were evaluated and possible factors associated with the pathophysiology of DMD are discussed. This is the first description of DMD in the veterinary literature, and the authors believe that DMD might hitherto have been overlooked in veterinary ophthalmology due to a lack of awareness of the condition. The possible causes, clinical signs, and treatment of DMD as described in the human literature are also reviewed. © 2014 American College of Veterinary Ophthalmologists.
Donaldson D.,Unit of Comparative Ophthalmology |
Matas Riera M.,Unit of Comparative Ophthalmology |
Holloway A.,Animal Health Trust |
Beltran E.,Animal Health Trust |
Barnett K.C.,Unit of Comparative Ophthalmology
Veterinary Ophthalmology | Year: 2014
Purpose: To investigate contralateral optic neuropathy and retinopathy following enucleation in 6 cats. Methods: Retrospective study. The medical records of cats with contralateral visual and afferent pupillomotor dysfunction following enucleation presented to the Animal Health Trust (AHT), Newmarket, UK, between January 1994 and January 2010 were reviewed. Information recorded included history, signalment, ophthalmic findings, electroretinography (ERG) (2/6) and MRI (3/6) findings and long-term outcome. Pearson's chi-square tests were used to compare breed proportions (P < 0.05). Results: Six cats aged 1.5 to 11 (median 5.5) years presented with mydriasis and/or visual deficits noted immediately following enucleation. Enucleation involved optic nerve (ON) ligation in all of the four cases for which this information was available. Ophthalmic findings included mydriasis with absent pupillary light reflex (PLR) (4/6), incomplete PLRs (2/6), absence of dazzle reflex (4/6) and absence of menace response (4/6). Funduscopy initially revealed multifocal peripapillary retinal lesions, with subsequent progressive optic nerve head (ONH) and retinal atrophy. ERG recordings revealed normal outer retinal function at 6 and 22 weeks (2/2). On MRI, the optic chiasm (OC) ipsilateral to the enucleation could not be identified and the contralateral OC was atrophied (3/3). Conclusions: The acute afferent ON deficits following enucleation, progressive ONH atrophy, normal outer retinal function and MRI demonstrating OC pathology are consistent with chiasmal injury due to traction on the ON during enucleation. Rostral traction on the globe to facilitate ON ligation is contraindicated in cats. © 2014 American College of Veterinary Ophthalmologists.