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Updated: Jul 17, 2026
In vivo Structural Assessments of Ocular Disease in Rodent Models using Optical Coherence Tomography
Published on: July 24, 2020
Tear clearance rate in dogs: Measurement using anterior segment optical coherence tomography
Hyun-Jeong Yoon1, Sangshin Park2,3, Joon-Young Kim1,4
1Department of Veterinary Ophthalmology, College of Veterinary Medicine, Konkuk University, Gwangjin-Gu, Seoul, Republic of Korea.
Objective:
The tear clearance rate (TCR), determined using anterior segment optical coherence tomography (AS-OCT) images, and its correlation with ocular surface parameters, including blink rate, Schirmer tear test-1 (STT-1) and tear film breakup time (TFBUT), were evaluated.
Animals Studied:
Left eyes of 20 client-owned dogs with no ocular disease symptoms.
Procedures:
The tear meniscus height (TMH) was evaluated using AS-OCT images before the instillation of 5 μL saline (TMHbase ), immediately post-instillation (TMH0 ), 30-s post-instillation (TMH0.5 ) and at 1 min intervals for 5 min post-instillation (TMH1 , TMH2 , TMH3 , TMH4 and TMH5 ). The TCR was calculated using the formula [(TMH0 - TMH0.5 )/TMH0 ]×100 (%). The eyes were classified into two groups with the median: 'High TMHbase ' (n = 10) and 'Low TMHbase ' (n = 10). Eyes with STT-1 values ≥15 mm/min and TFBUT ≥ 12 s were assigned to the 'Satisfied' subgroup, whereas eyes not satisfying these criteria were assigned to the 'Not satisfied' subgroup.
Results:
TMH0 was higher than TMH0.5 (p = 0.02), wherein TMH0.5 to TMH5 did not differ significantly. The TCR and blink rate were negatively correlated (p = 0.02). The 'Not satisfied' subgroup in the low TMHbase group had a lower TCR (p = 0.02) and higher blink rate (p = 0.04) than the 'Satisfied' subgroup.
Conclusions:
TCR can be evaluated using AS-OCT in dogs. Eyes with a lower TCR blink more frequently. TMH merits studying to understand ocular surface health.
