The effect of nilvadipine, a calcium-channel blocker, on the hemodynamics of retrobulbar vessels in normal-tension glaucoma

Purpose: To investigate the effect of nilvadipine, a calcium-channel blocker, on the hemodynamics of retrobulbar vessels in normal-tension glaucoma. Methods: Twenty-five patients who prospectively met the enrollment criteria underwent color Doppler imaging of the retrobulbar vessels before and after receiving 4 weeks of treatment with 2 mg oral nilvadipine twice daily. Results: Nilvadipine significantly increased the end-diastolic velocity in the central retinal artery and a short posterior ciliary artery. It significantly reduced the resistance index in the central retinal artery and posterior ciliary arteries, bur not in the ophthalmic artery. The calculated ocular perfusion pressure was not affected. Conclusion: Oral nilvadipine reduces vascular resistance in distal retrobulbar arteries in normal-tension glaucoma without affecting more proximal blood vessels. Therefore, nilvadipine may have a beneficial effect on the hemodynamics of retrobulbar vessels in normal-tension glaucoma.