Shuhei Komatsu

Endometrial stromal sarcoma located in the myometrium with a low-intensity rim on T2-weighted images: report of three cases and literature review.

Endometrial stromal sarcoma (ESS) most commonly grows from the uterine endometrium into the endometrial cavity; it is rarely located in the myometrium alone, where it may resemble degenerated leiomyoma on magnetic resonance imaging (MRI). We present three cases of intramyometrial ESS mimicking degenerated leiomyoma, all of which have a characteristic low‐intensity rim on T2‐weighted images. Histopathological examination revealed the rim to consist of fibrous tissue layers and/or a decrease in free water caused by distortion of myometrial tissue following tumor expansion. ESS should be included in the differential diagnosis of intramyometrial mass with low‐intensity rim on T2‐weighted image, especially if the mass shows degeneration with no or mild intratumoral hemorrhage. J. Magn. Reson. Imaging 2010;31:975–979. ©2010 Wiley‐Liss, Inc.

Influence of hemodynamic parameters on coronary artery attenuation with 320-detector coronary CT angiography.

OBJECTIVES To investigate the relationship between cardiac output, end diastolic volume and the contrast enhancement in coronary CT angiography using 320-detector CT. MATERIALS AND METHODS A total of 38 patients underwent coronary CT angiography by using a 320-detector CT scanner (detector configuration, 320 × 0.5mm). The attenuation value of the ascending aorta at the level of the orifice of the left main trunk was measured. The cardiac output (CO), end diastolic volume (EDV) and stroke volume (SV) were measured by echocardiography. The EDV was normalized to the body surface area (BSA). The total blood volume injected from the left ventricle from the beginning of the contrast agent injection to the time of image acquisition was determined to be the total injected blood volume (TIV), which is a product of SV and the number of heart beats from the initiation of contrast agent injection to the scan. RESULTS There was a negative correlation between the attenuation of the ascending aorta and CO (r = -0.44, P = 0.0053). However, the negative correlation between the attenuation of the ascending aorta and TIV was stronger (r = -0.52, P = 0.0007). There was a negative correlation between the attenuation of the ascending aorta and EDV/BSA (r = -0.45, P = 0.0039). CONCLUSION In 320-detector CT, contrast enhancement in CCTA with a lesser amount of contrast medium decreases when cardiac output is high. Patients with larger EDV/BSA may also show decreased attenuation.

Postsurgical spinal magnetic resonance imaging with iterative decomposition of water and fat with echo asymmetry and least-squares estimation.

Objective: Magnetic resonance imaging (MRI) is the most popular follow-up study for patients who have undergone spinal surgery. However, the image quality often becomes poor because of artifacts from metal implants and/or from failed fat suppression, which obscure diagnosis. Iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) is a new fat suppression method that is less affected by inhomogeneity of the magnetic field. Here, we compared postsurgical spinal MRI with IDEAL versus chemical shift selective saturation (CHESS). Methods: For 35 patients who had spinal surgery, we examined T2-weighted fast spin-echo sagittal images of the spine with both IDEAL and CHESS. Two radiologists evaluated the degrees of fat suppression and spinal canal projection from 0 (least/worst) to 2 (most/best). Results: Fat suppression and spinal canal scores for IDEAL were statistically higher than those for CHESS (P < 0.05). Conclusions: Iterative decomposition of water and fat with echo asymmetry and least-squares estimation is clinically useful for postoperative spinal MRI.