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Updated: Aug 25, 2026
Full-Circle Cauterization of Limbal Vascular Plexus for Surgically Induced Glaucoma in Rodents
Published on: February 15, 2022
Sustained perimacular vascular and visual response to topical beta blockers in normal human eyes
1South Texas Ocular Imaging Center, University of Texas Health Science Center, San Antonio, TX, USA. Sponsel@uthscsa.edu
Purpose:
To assess visual and circulatory responses to treatment with topical beta adrenergic antagonists.
Design:
Institutional prospective randomized clinical trial in normal adults.
Methods:
Twenty adults (36 (mean) +/- 8 (S.D.) years) underwent repeated baseline perimetry (Humphrey 30-2), contrast sensitivity (Vector Vision), perimacular microcirculatory studies (Oculix blue-field entoptic simulator), intraocular pressure (IOP), heart rate (HR), and blood pressure (BP) testing. Subjects commenced either timolol 0.5% or betaxolol 0.5% twice daily on day 1, were retested on days 3 and 35, discontinued treatment for 21 days, whereupon repeated tests were performed. Treatment responses were compared by paired t-test.
Results:
Timolol-treated eyes showed improvement in contrast sensitivity (P=0.03) and pericentral perimetric thresholds (P=0.01), but corresponding increases among betaxolol-treated eyes were significantly higher (P=0.03 and 0.04, respectively, relative to timolol-treated eyes). Leukocyte velocity increased with both drugs, each with post-withdrawal carryover (P< or =0.03). Significant IOP reduction (approximately 2.5 mmHg) occurred in both groups, BP fell 2.8 mmHg among betaxolol-treated subjects (P=0.02), and HR was 2 bpm slower among timolol-treated subjects (P=0.03), but all reverted to baseline values after washout.
Conclusions:
Both treatment groups demonstrated significant changes in visual function and perimacular hemodynamics, sustained after the terminal 3-week washout period.
