Effect of Timolol on Human Retinal, Choroidal and Optic Nerve Head Circulation

Yoshida, Akitoshi; Feke, Gilbert T.; Ogasawara, Hironobu; Goger, Douglas G.; Murray, DC; McMeel, J. Wallace

doi:10.1159/000267116

Cited by 62 publications

(33 citation statements)

References 16 publications

(28 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Regarding choroidal blood flow, our results agree with those of other investigators who studied the effect of timolol [10][11][12][13]. In ani mal studies, Parver et al [10], using the hy drogen washout technique, found that an intracameral injection of 5% timolol produced a significant decrease in choroidal blood flow in cats.…”

Section: Discussionsupporting

confidence: 90%

Effect of Timolol and UF-021 (a Prostaglandin-Related Compound) on Pulsatile Ocular Blood Flow in Normal Volunteers

et al. 1997

Self Cite

View full text Add to dashboard Cite

The effects of topically applied timolol (a nonselective beta-blocker) and UF-021 (a prostaglandin-related compound) on pulsatile ocular blood flow (POBF) were investigated in 9 healthy volunteers. One drop of either UF-021 or timolol was instilled in one randomly selected eye and the fellow eye received physiologic saline. Before and 90 min after drop instillation, we measured intraocular pressure (IOP), POBF, heart rate (HR) and blood pressure (BP). After a washout interval of at least 1 week, the other drug was instilled in the previously treated eye. IOP, POBF, HR, and PB were measured following the same protocol. After timolol administration, IOP and POBF decreased significantly in the treated eye (26%, p = 0.01, and 13%, p = 0.02, respectively) and in the fellow eye (11%, p = 0.01, and 11%, p = 0.03, respectively). HR also decreased (10%, p = 0.03), but BP did not change significantly. After UF-021 administration, no significant changes were found in IOP, POBF, HR, or BP. Our results suggest that in normal subjects timolol decreases POBF in both the treated and the untreated eyes, whereas UF-021 has no action on either IOP or POBF.

show abstract

Section: Discussionsupporting

confidence: 90%

Effect of Timolol and UF-021 (a Prostaglandin-Related Compound) on Pulsatile Ocular Blood Flow in Normal Volunteers

et al. 1997

Self Cite

View full text Add to dashboard Cite

show abstract

“…Nonselective β-blocking agents were reported to reduce choroidal and optic nerve head blood flow velocities but not blood flow velocity in the CRA, while a selective β-blocking agent, betaxolol, had no effect on choroidal and optic nerve head blood flow velocities [2, 6]. Harris et al [7]found that betaxolol decreases retrobulbar vessel resistance, whereas nonselective β-blockers leave that same distal vascular resistance unchanged.…”

Section: Discussionmentioning

confidence: 99%

“…All of the previous studies measured acute vascular effects of β-blockers. Two of them were performed on healthy subjects [2, 6]and the other [7]was performed on patients with normal-tension glaucoma. Great caution should be exercised when transferring the vascular data obtained from normal subjects to POAG patients, because the latter have a deficient autoregulation of retrobulbar blood flow [8].…”

Section: Discussionmentioning

confidence: 99%

The One-Month Effects of Topical Betaxolol, Dorzolamide and Apraclonidine on Ocular Blood Flow Velocities in Patients with Newly Diagnosed Primary Open-Angle Glaucoma

et al. 2001

View full text Add to dashboard Cite

Purpose: This double-masked, prospective and randomized clinical trial was planned to investigate with color Doppler imaging the 1-month vascular effects of betaxolol, dorzolamide and apraclonidine treatment on patients with newly diagnosed primary open-angle glaucoma (POAG). Methods: 22 consecutive patients with newly diagnosed POAG between the ages of 46 and 72 years were enrolled in this study. All patients were newly diagnosed cases and had not received any antiglaucoma medication before. Patients who had a systemic vascular disease (including systemic hypertension) or were taking β-blockers, nitrates or calcium channel blockers were excluded from the study. The patients were randomly divided into three groups. Groups A and B contained 7 patients, group C contained 8 patients. Group A patients were treated with topical betaxolol, group B patients received topical dorzolamide eye drops, and group C patients were treated with topical apraclonidine eye drops. Peak systolic velocities (PSV), end-diastolic velocities (EDV) and resistive indices (RI) in the right ophthalmic arteries (OA), central retinal arteries (CRA) and posterior ciliary arteries (PCA) were measured at baseline by using color Doppler imaging on a masked basis. On days 15 and 30 of treatment, the same measurements were repeated. The inter- and intragroup results were compared statistically. Results: Compared to pretreatment measurements, topical betaxolol therapy significantly decreased PSV only in the PCA and only on day 30 of treatment (p = 0.011). On days 15 and 30, dorzolamide decreased RI measurements in the PCA compared to pretreatment measurement (p = 0.013 and p = 0.011, respectively). Apraclonidine also decreased PSV in the OA on days 15 and 30 of treatment when compared to pretreatment values (p = 0.013 and p = 0.012, respectively). When 15-day measurements were compared between the groups, PSV in the OA were significantly higher in dorzolamide-treated patients compared to other groups (p = 0.01 and p = 0.011). On day 30 of treatment, PSV in the OA was also higher in the dorzolamide-treated group than the other groups (p = 0.012 and p = 0.01). Additionally, apraclonidine-treated patients had a significantly lower EDV in the OA than the other groups (p = 0.013 and p = 0.01). The RI in the OA was also significantly lower in the apraclonidine-treated group compared to the other groups (p = 0.01 and p = 0.011). Conclusion: Our study suggests that dorzolamide has the most advantageous 1-month effects on blood flow velocity in the retrobulbar arterial circulation of POAG patients. Betaxolol seems superior to apraclonidine in this regard. Our data may help the clinician when treating patients with POAG medically. Further studies using a larger population size may clarify our results.

show abstract

“…There has been no report regarding the effects of travoprost, bimatoprost or tafluprost on ONH blood flow in humans as far as we know. It is reported that timolol either had no significant effect on or decreased ONH blood flow in humans (Yoshida et al, 1991;Tamaki et al, 1997aTamaki et al, , 1997bNetland et al, 1999;Haefliger et al, 1999;Lübeck et al, 2001). In contrast, carteolol, betaxolol and nipradilol reportedly increased ONH blood flow in humans (Tamaki et al, 1997a(Tamaki et al, , 1997bTamaki et al, 1999;Mizuno et al, 2002).…”

Section: Introductionmentioning

confidence: 99%