Changes in retinal blood flow after application of topical dipivefrine 0.1%

Purpose: Most of the antiglaucomatous drugs affect ocular blood flow. Blood flow of the anterior uvea under the effect of glaucoma medication has been described in the literature, but measurement of microcirculation at the po sterior pole correlated to glaucoma medication is rarely found. We present a placebo-controlled study in which we focused on the short and long-term e ffects of topical dipivefrine 0.1 % on the microcirculation of the retina a nd optic nerve head. Patients and methods: In a randomized, placebo-controlled double-masked stu dy we examined 40 healthy persons (21 male and 19 female) with a mean age o f 35 +/- 4.6 years. Two groups of volunteers (n = 20) were treated either w ith placebo or dipivefrine 0.1 % for 5 days twice a day. Measurement of mic rocirculation was done at baseline, 30 min after the first application and on days 3 and 5. Microcirculation was evaluated by scanning-laser Doppler f lowmetry (SLDF, Heidelberg Engineering; Heidelberg, Germany) [retinal and o ptic nerve head capillary blood flow (ONH)]. Systemic parameters were check ed at all times of blood flow measurement (blood pressure, pulse); intraocu lar pressure (IOP) was also measured at baseline, 30 min after and on days 3 and 5. Results: Systemic parameters: None of serum medications affected blood pres sure or pulse. Dipivefrine 0.1 % lowered the IOP significantly (P = 0.01). Microcirculation: dipivefrine 0.1 % leads to a significant reduction of ret inal capillary blood flow (P = 0.01). ONH blood flow was not significantly affected by dipivefrine 0.1 %. Conclusion: Retinal capillary perfusion is affected by dipivefrine 0.1 % me dication. In neuroprotection, it is of interest that glaucoma medication di d not alter the microcirculation in a way that leads to an increase of hypo xemia. Therefore, we consider dipivefrine 0.1 % not to be useful for long-t erm glaucoma treatment.