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Published on: July 4, 2018
Quantitative assessment of pupillary light reflex in normal and anesthetized dogs: a preliminary study
Jury Kim1, Jiseong Heo, Dongbeom Ji
1College of Veterinary Medicine, Chonbuk National University, 664-14 Duckjin-dong, Duckjin-ku, Jeonju 561-756; Ji dong Beom Animal Hospital, 266-10 Bugok-dong, Geumjeong-ku, Busan, 609-822, Republic of Korea.
Abstract:
The purpose of this study was to quantitatively assess the pupillary light reflex (PLR) in normal and anesthetized dogs using a pupillometer. Eleven dogs (20 eyes) of various breeds were included. PLRs were measured with a handheld pupillometer in dim light before and during anesthesia. Anesthesia was conducted with atropine, xylazine and ketamine. Parameters of pupillometry included neurological pupil index (NPi), pupil size, percent of change (%CH), latency (LAT), constriction velocity (CV), maximum constriction velocity (MCV) and dilation velocity (DV). NPi,%CH, CV and MCV were significantly decreased during anesthesia compared with the pre-anesthesia data. The results suggest that atropine-xylazine-ketamine combination anesthesia depresses the PLR. Additionally, this study demonstrates the feasibility of the use of a pupillometer in dogs.
