Effect of IOP-lowering treatment and Pentoxifylline on retrobulbar blood flow in normal tension glaucoma: a color doppler imaging study.

PURPOSE: To evaluate the effect of combining topical intraocular pressure (IOP)-lowering medications with oral pentoxifylline on ocular blood flow in patients with normal tension glaucoma (NTG), using Color Doppler Imaging (CDI). METHODS: In this pilot study, we retrospectively identified NTG patients who underwent IOP-lowering therapy followed by oral pentoxifylline administration. Three study visits were considered: baseline (V1) without therapy, after IOP-lowering therapy (V2), and following the addition of oral pentoxifylline (V3). Each visit included: IOP and blood pressure measurements, CDI of central retinal artery (CRA), and short posterior ciliary arteries (SPCAs). CDI parameters analyzed included peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive index (RI). The healthy control group with CDI of ocular vessels was used to establish a threshold for “impaired” versus “normal” flow based on the 5th percentile of CDI parameters. RESULTS: Nine NTG patients (18 eyes) were considered. Following topical IOP-lowering therapy (V2), IOP decreased significantly (16.50 ± 2.96 mmHg at V1 to 12.33 ± 1.80 mmHg at V2; p < 0.0001), PSV in impaired CRA showed a notable increase (p < 0.0079), though blood flow changes in SPCAs were minimal. With the addition of pentoxifylline at V3, PSV and EDV significantly improved across impaired SPCAs. No changes were noted in CDI parameters in the normal SPCAs. CONCLUSIONS: Combined therapy with topical IOP-lowering medications and oral pentoxifylline in NTG patients enhanced CDI parameters in vessels with initially impaired flow. This approach may provide a beneficial, vascular-targeted treatment for NTG management.