The short-term effect of latanoprost on intraocular pressure and pulsatile ocular blood flow

Purpose: There is evidence that ocular blood flow plays a critical role in the clinical course of glaucoma. Any reduction in ocular blood flow due to topical antiglaucoma treatment should therefore be avoided. This study aimed to evaluate the short-term effect of local latanoprost application on ocular hemodynamics. Methods: Intraocular pressure (IOP), ocular pulse amplitude (OPA), ocular pulse volume (OPV), systemic blood pressure, heart rate and the pulsatile component of ocular blood flow (POBF) were recorded using a pneumotonometer linked to the Langham Ocular Blood Flow System in 24 patients in a prospective, open-label study before and after 1 week of topical latanoprost application in both eyes. Twenty of the subjects had primary open-angle glaucoma and four had ocular hypertension. Results: After 1 week of latanoprost treatment, IOP decreased significantly 6.2 +/- 2.9 mmHg in OD (P < 0.001) and 6.2 +/- 3.2 mmHg in OS (P < 0.001). Pulsatile OBF increased significantly by 201.2 +/- 167.4 muL/min in OD (P < 0.001) and 203.8 +/- 187.3 muL/min in OS (P<0.001). Ocular pulse amplitude and OPV showed statistically significant increases (P < 0.05 and P < 0.001 respectively). Blood pressure and heart rate did not change significantly. Conclusion: Our results indicate that 1 week after latanoprost application, POBF, OPA and OPV were significantly increased in the eyes treated. More information on the perfusion of the optic nerve head is needed before the relevance of these findings to optic nerve head blood flow can be interpreted correctly.