Yoshihiro Odawara

Visceral obesity in Japanese patients with metabolic syndrome: reappraisal of diagnostic criteria by CT scan.

To reappraise the cutoff level of abdominal circumference (AC) for diagnosis of visceral obesity in Japanese, we examined the association of visceral fat deposition with other constituents of metabolic syndrome and atherosclerotic cardiovascular disease (ASCD). CT was used for determination of visceral-fat area (VFA), subcutaneous-fat area (SFA) and AC on CT (ACCT) in 420 Japanese patients with (n=180) or without ASCD (n=240). VFA cutoff levels were calculated by receiver operating characteristic (ROC) analysis. ACCT correlated with VFA (r=0.828), SFA (r=0.795), and AC measured with an anthropometric tape (ACM, r=0.96). The VFA cutoff levels yielding the maximum sensitivity and specificity to predict two or more components of metabolic syndrome were 92 cm2 in males and 63 cm2 in females, which correspond to ACM values of 83 cm and 78 cm, respectively. The male ACM cutoff level was similar to the AC in current Japanese criteria (85 cm), but the female ACM cutoff level was considerably smaller than the criteria, and this change in cutoff level increased the prevalence of metabolic syndrome in females three-fold. The cutoff levels of VFA for predicting presence of ASCD were 98 cm2 in males and 75 cm2 in females, corresponding to ACM values of 84 cm and 80 cm, respectively. The present results obtained by CT support the validity of the current Japanese criteria for visceral obesity in males but not in females. ACM of 78 cm appears to be a cutoff level suitable for diagnosing visceral obesity in Japanese females, though further confirmation is needed.

Three-Dimensional Imaging of the Temporal Bone Using a Helical CT Scan and Its Application in Patients with Cochlear Implantation

Recent advanced techniques for the reconstruction of three-dimensional (3D) images allow further visual recognition of the fine structures of the temporal bone. We demonstrate the advantages of reconstruction 3D imaging in helical CT scans of the normal temporal bone and in patients who have received cochlear implants. After the temporal bone was scanned in the axial plane in the helical scan mode, the data were transferred to a workstation and 3D reconstruction was performed. The normal temporal bone structures were well recognized on these 3D images. The spatial relationship between the lymphatic space of the inner ear and the electrode array is visible. This method provides a detailed anatomy of the insertion of the electrodes into the cochlea and provides precise images of electrode routes by means of varying the angles of view on the computer display. Individual electrodes could not be distinguished. The information from 3D images may be useful not only for pre-but also postoperative investigations in cochlear implantation.