平井 都始子¹, 大石 元¹, 東泉 隆夫², 森田 大², 地挽 隆夫², 見山 広二², 打田 日出夫¹

Toshiko HIRAI¹, Hajime OHISHI¹, Takao HIGASHIIZUMI², Dai MORITA², Takao JIBIKI², Kouji MIYAMA², Hideo UCHIDA¹

¹奈良医科大学腫瘍放射線科・放射線科, ²横河メディカルシステム(株)

¹Departments of Oncoradiology and Radiology, Nara Medical University, ²Yokogawa Medical Systems Ltd.

キーワード : Phantom, Color flow mapping, Slice thickness

Color flow mapping (CFM) slice thickness was evaluated using a flow phantom. Using conditions similar to those in vivo, we set the flow phantom attenuation to 0.8 dB/cm/MHz, and acoustic velocity at 1,535 to 1,545 m/s. For the paravessels, silicon tubes with an inner diameter of 0.8 mm were used. The US device was a Yokogawa RT8000 with a 3.5 MHz convex probe. Parablood was passed through the silicon tubes at a rate of 0.1 ml/s. Under the initial setting conditions, when the velocity scale was set at 36 cm/s, slice thickness at depth of 2-6 cm was 5-6 mm. The 0.8 mm paravessels were displayed as color signals approximately 4 mm in size.
A tumor phantom was prepared by winding a paravessel around the pseudo-tumor, and the color Doppler flow images of the phantom were observed. When the pseudo-tumor and paravessel were on the same plane, the vessel was displayed in color around the margin of the tumor. When they were positioned in the direction of slice thickness, the vessel appeared in its color display as if it existed inside the tumor.
When diagnosing by CFM, this phenomenon should be kept in mind.