NeuroradiologyThe effect of Xenon Inhalation Speed on Cerebral Blood Flow Obtained Using the End-Tidal Method in Xenon-Enhanced CTSase, Shigeru Author Information From the Anzai Medical Corporation, 3-9-15 Nishi-Shinagawa, Shinagawa-ku, Tokyo 141-0033, Japan. Address correspondence and reprint requests to Dr. S. Sase. Journal of Computer Assisted Tomography: September 1998 - Volume 22 - Issue 5 - p 786-791 Buy Abstract Purpose: The purpose of this work is to show how variations in inhalation speed of xenon gas affect cerebral blood flow (CBF) values obtained using the end-tidal method on xenon-enhanced CT (Xe-CT). We tried to clarify whether arterial exon concentration could keep up with end-tidal xenon concentration by evaluating the effect of xenon inhalation speed on calculated CBF values. Method: The same subject underwent two or three consecutive Xe-CT examinations, varying xenon inhalation speed. The rate constants of applied inhalation speeds were 0.1-0.15 min-1 (low speed), 0.25-0.3 min-1 (middle speed), and 1-2 min-1 (high speed), respectively. Results: No significant difference was observed among the CBF values of the same subject obtained under different inhalation speeds. Conclusion: End-tidal xenon can closely reflect arterial xenon under the customary method of xenon supply. The end-tidal method can provide reliable absolute CBF values, assuming actual CBF values are substantially unchanged regardless of the inhalation speed variation applied in this work. © 1998 Lippincott Williams & Wilkins, Inc.