Quantitative evaluation for intravascular structures of vertebral artery dissection with a novel zoomed high-resolution black-blood MR imaging.

BACKGROUND: Although non-stroke vertebral artery dissection (VAD) is diagnosed using MRI, detecting the subtle intravascular structure remains challenging. This study aimed to evaluate the validity of quantitative intravascular scanning based on novel zoomed high-resolution black blood (Z-HB) MRI for distinguishing VAD from other vessel pathologies. METHODS: Twenty-one patients with non-stroke VAD and 18 with symptomatic atherosclerotic plaques in their vertebral artery underwent Z-HB MRI and subsequent profile curve processing. Axial Z-HB imaging was obtained from dissected and normal segments in patients with VAD and atherosclerotic plaque in patients with ischemia. We investigated the qualitative categorization of the scanning patterns of the intravascular signals. We also evaluated the quantitative ability of each profile curve to discriminate multiple vessel pathologies by analyzing the receiver operating characteristics curves. RESULTS: Profile curve processing of 140 Z-HB images categorized the intravascular signal patterns into luminal, asymmetrical, and omega types. The asymmetrical type included both dissecting and atherosclerotic vessels, and the omega type included dissecting and normal vessels. In the asymmetrical type, quantitative evaluation successfully distinguished intramural hematomas of VAD from atherosclerotic plaque with an area under the curve of 0.80. The intimal flap of the VAD was distinguished from the blood flow artifact of the normal vessel with an area under the curve of 0.93 in the omega type. CONCLUSIONS: A combination of novel Z-HB MRI and profile curve processing provided an ultra-high-resolution analysis of the intravascular structure of non-stroke VAD and successfully distinguished VAD from normal vessels or atherosclerotic plaques.

[Role of weighted maximum intensity projection with MDCT in the diagnosis of skull fractures].

The method of image processing has increased along with the workstation in recent years and developments in the software of each modality. Maximum intensity projection (MIP) and volume rendering (VR) are among the general processing methods used. However, MIP and VR have their respective limitations. MIP does not have in-depth information, and in VR the final image depends on threshold processing. In comparison with MIP/VR, Weighted MIP can obtain in-depth information. The processing method is also easy and is used in the pre-operative simulation of neurosurgical craniotomy. In this study, we examined the effect of Weighted MIP on a phantom and in 7 cases of skull fracture by using multi-detector-row computed tomography. In the phantom study, Weighted MIP provided three-dimensional imaging in all the processing methods for skull fractures. Weighted MIP depicted the entire fracture line in a clinical study, and it was effective in all of the 7 skull fracture cases. In conclusion, the present study demonstrated that Weighted MIP with depth information was effective in the fracture line detection of skull fracture.

[Usefulness of volume rendering stereo-movie in neurosurgical craniotomies].

In recent years, the advancements in MR technology combined with the development of the multi-channel coil have resulted in substantially shortened inspection times. In addition, rapid improvement in functional performance in the workstation has produced a more simplified imaging-making process. Consequently, graphical images of intra-cranial lesions can be easily created. For example, the use of three-dimensional spoiled gradient echo (3D-SPGR) volume rendering (VR) after injection of a contrast medium is applied clinically as a preoperative reference image. Recently, improvements in 3D-SPGR VR high-resolution have enabled accurate surface images of the brain to be obtained. We used stereo-imaging created by weighted maximum intensity projection (Weighted MIP) to determine the skin incision line. Furthermore, the stereo imaging technique utilizing 3D-SPGR VR was actually used in cases presented here. The techniques we report here seemed to be very useful in the pre-operative simulation of neurosurgical craniotomy.