Doppler ultrasonographic measurement of short‐term effects of valsalva maneuver on retrobulbar blood flow

ABSTRACTBackgroundTo investigate the effects of Valsalva maneuver (VM) on retrobulbar blood flow parameters in healthy subjects.MethodsParticipants without any ophthalmologic or systemic pathology were examined in supine position with color and pulsed Doppler imaging for blood flow measurement, via a paraocular approach, in the ophthalmic artery (OA), central retinal artery (CRA), central retinal vein (CRV), nasal posterior ciliary artery (NPCA), and temporal posterior ciliary artery (TPCA), 10 seconds after a 35‐ to 40‐mm Hg expiratory pressure was reached. Peak systolic velocity (PSV), end‐diastolic velocity (EDV), pulsatility index (PI), and resistivity index (RI) values were recorded for each artery. PSV and EDV values were recorded for CRV.ResultsThere were significant differences between resting and VM values of PSV and EDV of CRA, RI of NPCA, and PI, RI, and EDV of TPCA. Resting CRA‐EDV, CRV‐PSV, and CRV‐EDV were positively correlated whereas resting OA‐PSV and CRA‐PI, and OA‐PSV, CRA‐PSV, and CRA‐EDV during VM, were negatively correlated with age.ConclusionsVM induces a short‐term increase in CRA blood flow and a decrease in NPCA and TPCA RI. Additional studies with a longer Doppler recording during VM, in a larger population sample, are required to allow definitive interpretation. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:551–555, 2017