Presumed neuroprotective therapies prescribed by veterinary ophthalmologists for canine degenerative retinal and optic nerve diseases

Owners' experiences of administering meglumine antimoniate injections to dogs with leishmaniosis: An online questionnaire study

BACKGROUND

This study examined the experiences of owners of dogs with leishmaniosis who treated their dogs with daily subcutaneous meglumine antimoniate injections. The owners' perceived ease of administering the injections, the occurrence of problems and the effects on the owners and on the dog‒owner bond were evaluated.

METHODS

Dogs prescribed meglumine antimoniate as a treatment for leishmaniosis were identified using the database of the veterinary pharmacy of the Faculty of Veterinary Medicine, Utrecht University. An online questionnaire was sent to the owners of these dogs to evaluate the perceived ease of administering the injections, the occurrence of problems and the effects on the owner and the dog-owner bond.

RESULTS

Responses were received from 64 dog owners. Most respondents (78%) reported that administering the injections was not difficult. Pain or the development of nodules at the injection site was reported in 50% and 40% of the dogs, respectively. Polyuria was reported in 44% of the dogs. Some owners reported that administering the injections had a negative impact on their psychological wellbeing (20%), and some would have liked more veterinary support (11%).

LIMITATIONS

Some questions were answered by a limited number of people, and their responses may not be representative.

CONCLUSION

Dog owners remain highly motivated to persevere with meglumine antimoniate treatment and are willing to administer the injections themselves. The availability of active support when needed during the therapy cycle may further improve their acceptance of and confidence in giving the injections.

Micropulse transscleral cyclophotocoagulation in canine glaucoma: A retrospective study evaluating sweep velocity

OBJECTIVE

To report preliminary results of MP-TSCP in canine patients with glaucoma while evaluating sweep velocity, treatment efficacy, and safety utilizing standardized surgical parameters.

ANIMAL STUDIED

Client-owned dogs that underwent MP-TSCP at a veterinary referral hospital.

PROCEDURE

Medical records of 19 eyes (14 dogs) treated with MP-TSCP were reviewed. Eleven eyes were treated with a 10 s/sweep (s) velocity and 8 eyes with a 20 s/s. Laser duty cycle was set at 31.3%, mean laser energy was 2766 mW, and mean duration was 120 s per hemisphere. Minimum post-operative follow-up was 6 months. Outcomes of intraocular pressure (IOP), vision status, degree of antiglaucoma medications, and complications were evaluated.

RESULTS

There was a significantly lower median (IQR) IOP (<25 mmHg) at each timepoint postoperatively compared to IOP pre-operatively (p < 0.05). The overall success rate for IOP control at 6 months was 84%, 100% for the 10 s/s and 62.5% for the 20 s/s. Vision was preserved in 10/11 (90%) eyes from the 10 s/s group and 4/8 (50%) eyes from the 20 s/s group at 6 months. Average number of glaucoma medications in the 10 s/s group decreased from 4.4 to 1.5 and from 3.3 to 2.5 in the 20 s/s group. Post-operative complications were mild and resolved within 1 week.

CONCLUSIONS

MP-TSCP is a non-invasive treatment alternative for canine glaucoma. Employing higher energy levels rendered long-term IOP control while retaining a high safety profile with minimal postoperative complications. There was no statistical difference between a 10 s/s and 20 s/s surgical velocity, both leading to successful surgical outcomes up to 6 months post-operatively.

Manifestations of systemic disease in the retina and fundus of cats and dogs

The fundus is unique in that it is the only part of the body that allows for a noninvasive and uninterrupted view of vasculature and nervous tissue. Utilization of this can be a powerful tool in uncovering salient incidental findings which point to underlying systemic diseases, and for monitoring response to therapy. Retinal venules and arterioles allow the clinician to assess changes in vascular color, diameter, outline, and tortuosity. The retina and optic nerve may exhibit changes associated with increased or decreased thickness, inflammatory infiltrates, hemorrhages, and detachments. While some retinal manifestations of systemic disease may be nonspecific, others are pathognomonic, and may be the presenting sign for a systemic illness. The examination of the fundus is an essential part of the comprehensive physical examination. Systemic diseases which may present with retinal abnormalities include a variety of disease classifications, as represented by the DAMNIT-V acronym, for Degenerative/Developmental, Anomalous, Metabolic, Neoplastic, Nutritional, Inflammatory (Infectious/Immune-mediated/ischemic), Toxic, Traumatic and Vascular. This review details systemic illnesses or syndromes that have been reported to manifest in the fundus of companion animals and discusses key aspects in differentiating their underlying cause. Normal variations in retinal anatomy and morphology are also considered.

Role of Inflammation in Canine Primary Glaucoma

Primary glaucoma is a painful, progressive, and blinding disease reported in many canine breeds, characterized by intraocular pressure (IOP) elevation in the absence of antecedent intraocular disease. Clinical observations of dogs with primary glaucoma suggest that many affected eyes develop concurrent intraocular inflammation in addition to elevated IOP. In this work, we summarize the current knowledge that relates inflammation to primary glaucoma in dogs, reviewing studies focused on genetics, physiology, histopathology, bioanalysis of ocular fluids, therapeutics, and clinical outcomes of glaucomatous patients. Through disruption of the blood-aqueous and blood-retinal barriers, pigment dispersion, and biochemical changes to the aqueous humor and tear film, the pathogenesis of canine primary glaucoma appears to involve inflammatory changes to various extents and with various consequences from the front to the back of the eye. Among others, inflammation further impacts IOP by reducing aqueous humor outflow at the level of the iridocorneal angle and accelerates vision loss by promoting neuronal degeneration. As such, the vicious cycle of ocular inflammation and IOP elevation might warrant the use of anti-inflammatory medications as a core component of the treatment regime for dogs with primary glaucoma, either therapeutically (i.e., actively glaucomatous eye) or prophylactically in the yet unaffected contralateral eye.