Changes in intraocular pressure and horizontal pupil diameter during use of topical mydriatics in the canine eye
Journal Title: Open Veterinary Journal - Year 2017, Vol 7, Issue 1
Abstract
The objective of this study was to determine the effects of topical 0.5% tropicamide, 1% atropine sulphate and 10% phenylephrine hydrochloride ophthalmic solutions on intraocular pressure (IOP) and horizontal pupil diameter (HPD) in the dog during the first hour after treatment. Forty clinically and ophthalmologically normal canine patients (between the ages of 2 and 6 years) of varying breed and sex were used in this study. Animals were randomly divided into four groups of ten and given one drop of tropicamide, atropine, phenylephrine or saline into one eye. IOP and HPD were measured in both eyes every 5 minutes for 60 minutes. Tropicamide increased IOP by 8.8±4.0 mmHg 35 minutes post-treatment compared to pre-treatment (P<0.01) only in treated eye. IOP in the contralateral eye did not increase. With atropine the maximum increase in IOP was 2.6±2.8 mmHg at 20 minutes post treatment in the treated eye (P<0.01). IOP in the contralateral eye did not increase. Phenylephrine increased IOP by 2.3±2.1 mmHg (P<0.05) 10 minutes after treatment. Also in the untreated eye IOP increased by 2.3±2.1 mmHg, 20 minutes post-treatment. Maximum HPD in eyes treated with tropicamide occurred at 55 minutes and with atropine at 60 minutes. There were no HPD changes in the contralateral, untreated eye. Topical 10% phenylephrine showed maximal pupil dilation 60 minutes after treatment, but the HPD of the – untreated eye slightly decreased at 15 minutes, but this change only reached statistical significance at 40 min post- treatment (P<0.05). Normal saline showed no influence on IOP or HPD. The drugs investigated here show a significant increase in IOP after mydriatics.
Authors and Affiliations
Liga Kovalcuka| Latvia University of Agriculture, Faculty of Veterinary Medicine, Clinical Institute, K. Helmaņa iela 8, Jelgava, LV-3004, Latvia, Agris Ilgazs| Latvia University of Agriculture, Faculty of Veterinary Medicine, Clinical Institute, K. Helmaņa iela 8, Jelgava, LV-3004, Latvia, Dace Bandere| Riga Stradiņš University, Faculty of Pharmacy, Department of Pharmaceutical Chemistry, Dzirciema iela 16, Rīga, LV-1007, Latvia, David L. Williams| University of Cambridge, Department of Veterinary medicine, United Kingdom
Effects of xylazine-ketamine anesthesia on plasma levels of cortisol and vital signs during laparotomy in dogs
This study was designed to evaluate effects of xylazine-ketamine anesthesia on plasma levels of cortisol and vital signs during and after laparotomy in dogs. Eight clinically healthy, adult male dogs, weighing 20 kg wer...
Calcitonin-negative primary neuroendocrine tumor of the thyroid (nonmedullary) in a dog
The Calcitonin-negative neuroendocrine tumor of the thyroid (CNNET) or "nonmedullary" in humans is a rare tumor that arises primarily in the thyroid gland and may be mistaken for medullary thyroid carcinoma; it is chara...
Raw cow’s milk relatively inhibits quorum sensing activity of Cromobacterium violaceum in comparison to raw she-camel’s milk
Milk from different animal species has variable levels of antimicrobial factors against some of spoilage bacteria. For example, they are significantly present in higher concentration in she-camel’s milk than in cattle...
Cellular and molecular etiology of hepatocyte injury in a murine model of environmentally induced liver abnormality
Exposures to a wide variety of environmental substances are negatively associated with many biological cell systems both in humans and rodents. Trichloroethane (TCE), a ubiquitous environmental toxicant, is used in larg...
Metastatic intraocular hemangiopericytoma in a dog
A 10-year-old Labrador Retriever who had been undergoing therapy for a recurrent hemangiopericytoma of the right flank presented to the Kansas State University Ophthalmology service for evaluation of a painful left eye....