Intro to SAH Normal MCA velocities are 30-80 cm/s. Only low (< 120 cm/s) or high (> 200 cm/s) absolute velocities consistently correlate with arterial narrowing [Neurosurgery 44: 1237, 1999] – since most patients fall in an intermediate range, invasive treatment should not be based on these values alone. Instead, TCDs should be used as […]