Effect of dorzolamide timolol combination versus timolol 0.5% on ocular bloodflow in patients with primary open-angle glaucoma.
OBJECTIVE
Addition of dorzolamide to timolol in primary open-angle glaucoma shows augmented reduction of intraocular pressure. It is unknown as yet if addition of dorzolamide will alter hemodynamics.


METHODS
Fifteen patients with primary open-angle glaucoma were placed on a medication-dependent 1-week to 4-week washout that included maintenance on timolol. After washout, baseline measurements were taken (timolol). They were studied after a month on timolol or dorzolamide-timolol (Cosopt; Merck, Inc, Whitehouse Station, New Jersey), with the second drug preceded by another month of timolol maintenance and second baseline measurements. At each visit, visual function, intraocular pressure, and ocular hemodynamics were monitored, including indocyanine green and fluorescein angiography and color Doppler imaging.


RESULTS
Cosopt significantly reduced intraocular pressure (14.7 to 13.4 mm Hg, P <.05) and increased arteriovenous passage time (superior temporal artery) of fluorescein dye (2.13 to 1.76 seconds, P =.01) but had no effect on visual function.


CONCLUSIONS
When compared with timolol in primary open-angle glaucoma, Cosopt augments ocular tension reduction and reduces the amount of time required for blood to pass through the superior retinal vasculature.
Harris
A
A
Department of Ophthalmology, Indiana University School of Medicine, 702 Rotary Circle, Indianapolis, IN 46202, USA. alharris@indiana.edu
Jonescu-Cuypers
C P
CP
Kagemann
L
L
Nowacki
E A
EA
Garzozi
H
H
Cole
C
C
Martin
B
B
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001783:Blood Flow Velocity; D019842:Ciliary Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005123:Eye / Q000098:blood supply*; D005451:Fluorescein Angiography; D005902:Glaucoma, Open-Angle / Q000188:drug therapy / Q000503:physiopathology*; D006801:Humans; D007208:Indocyanine Green; D007429:Intraocular Pressure / Q000187:drug effects*; D017078:Laser-Doppler Flowmetry; D009880:Ophthalmic Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D009883:Ophthalmic Solutions; D009887:Ophthalmoscopy; D012039:Regional Blood Flow; D012161:Retinal Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D013449:Sulfonamides / Q000008:administration & dosage / Q000627:therapeutic use*; D013876:Thiophenes / Q000008:administration & dosage / Q000627:therapeutic use*; D013999:Timolol / Q000008:administration & dosage / Q000627:therapeutic use*; D014065:Tonometry, Ocular; D014463:Ultrasonography; D014792:Visual Acuity
D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents; D009883:Ophthalmic Solutions; D013449:Sulfonamides; D013876:Thiophenes; D013999:Timolol; C062765:dorzolamide; D007208:Indocyanine Green