Anterior segment parameters in normal dogs using the Pentacam® HR Scheimpflug system.

Abstract

To describe and compare normative anterior segment parameters between canine age groups using the Pentacam® HR Scheimpflug camera (Pentacam). Thirty-six sedated dogs (60 eyes) of varying ages and breeds were imaged with the Pentacam; only nondiseased anterior segments were included. Dogs were divided into three age groups: Group 1 (1-5years), Group 2 (6-10years), and Group 3 (11-15years). Values assessed included central corneal thickness (CCT), anterior and posterior corneal elevation (ACE/PCE), anterior and posterior corneal curvature metrics, corneal volume (CV), anterior and posterior corneal astigmatism (AA/PA), anterior chamber depth (ACD), anterior chamber volume (ACV), and anterior chamber angle (ACA). Tukey-adjusted pairwise comparisons were performed. Overall CCT (mean±SD) was 631.07±59.91µm. Central corneal thickness was 608.60±48.63µm for Group 1, 648.57±51.06µm for Group 2, and 635.37±73.71µm for Group 3. Anterior corneal elevation (ACE) measured 9.08±0.58mm, PCE measured 8.04±0.50mm, and CV was 58.13±5.39mm3 . Astigmatism values were 1.34±0.94D for AA and 0.46±0.44D for PA. Anterior chamber values were 3.76±0.56mm for ACD, 383.68±66.24mm3 for ACV, and 23.62±29.33˚ for ACA. Significant differences were found between Groups 1 and 2 for CV (55.08±4.08mm3 and 60.32±4.19mm3 , respectively), (P=0.02). Corneal volume significantly increased between Group 1 and Group 2. Central corneal thickness increased from Group 1 to Group 3, but was not significant with the current sample size. There were no other differences between age groups.