[Accuracy Verification for Slice Sensitivity Profile Measurement Method by Averaging the Multiple Tilted Wires in Computed Tomography Image].

Purpose: Several studies present the unsuitability of the tilted-wire method for slice sensitivity profile (SSP) in helical scan. We compared the accuracy for SSP by the tilted-wire averaging method using multiple wire profiles and by the conventional micro-coin method.

Methods: A micro-coin phantom positioned at the center or the off-center was scanned using a 64-detector row CT scanner in different positions where an X-ray tube starts scanning.

[Evaluation of low-contrast resolution for liver image in digital phantom and clinical image].

The high performance of multi detector-row computed tomography (MDCT), enables a flow dynamic study of the liver that can be carried out within 10 seconds per one phase. In addition, it has been possible to obtain a stable image quality by utilizing the auto exposure control system. However, no clear standard of minimal CT value differences and minimal tumor sizes for detecting liver tumors has ever been shown.

3D-CT arteriography and 3D-CT venography: the separate demonstration of arterial-phase and venous-phase on 3D-CT angiography in a single procedure.

Although 3D-CT angiography provides valuable anatomic information regarding lesion and their surrounding vessels and bony structures, it cannot demonstrate lesions, arteries, and veins, separately. The separate demonstration of arterial-phase 3D-CT angiography (3D-CT arteriography) and venous-phase 3D-CT angiography (3D-CT venography) will facilitate the understanding of the vascular anatomy within lesions, thus, allowing improvement of diagnostic accuracy and potentially a safer surgical approach. We describe 3D-CT arteriography and 3D-CT venography by using a multidetector row helical CT.

Acute aneurysm surgery using three-dimensional CT angiogrphy without conventional catheter angiography.

The object of this study is to assess whether aneurysm surgery can be performed in patients with ruptured cerebral aneurysms by using three-dimensional computerized tomography angiography (3D-CTA) alone, without conventional catheter angiography (CCA). Between May 1994 and November 1996, a consecutive series of 60 cases of ruptured cerebral aneurysms was evaluated by both 3D-CTA and CCA prospectively and compared the detectability of cerebral aneurysms. Both 3D-CTA and CCA demonstrated a 100% diagnostic accuracy of ruptured cerebral aneurysms.