Hematocrit and Serum Hemoglobin Do Not Influence Values in Computed Tomography Perfusion of Patients With Acute Ischemic Stroke.

OBJECTIVE: There is a correlation between both serum hemoglobin (HGB) and hematocrit (HCT) and attenuation values of vessels in noncontrast-enhanced computed tomography (NECT), which could influence calculated perfusion maps in CT perfusion.

METHODS: We retrospectively included 45 patients, who presented with acute new neurological symptoms and underwent NECT and CT perfusion (128-row multi detector scanner, coverage: 6.9 cm craniocaudally; 80 kV; 200 mAs; temporal resolution: 2 seconds using 40 mL Ultravist 370 at a flow rate of 5 mL/s) on admission and a follow-up MRI within 1 week of admission.

RESULTS: Hematocrit, HGB, and attenuation values did not differ between patients with stroke and controls. A statistically significant correlation was found between HCT and HGB and attenuation values in the internal carotid artery or middle cerebral artery on NECT (P < 0.05). No statistically significant correlation was observed between HCT and HGB and perfusion maps.

CONCLUSIONS: Hematocrit and HGB do not influence calculated perfusion maps. There is no need for HCT/HGB-adjusted cerebral blood volume thresholds in stroke patients.