A combination of BI-RADS MRI descriptors and clustered ring enhancement criteria is useful for the differential diagnosis of lesions showing non-masslike enhancement.

A sinonasal mass with a convoluted cerebriform pattern on T2- or enhanced T1-weighted images suggests inverted papilloma as a histologic diagnosis. Necrosis in a mass with such an appearance strongly suggests coexistent carcinoma.

Clustered ring enhancement is thought to be a useful sign to differentiate between benign and malignant lesions, in addition to the BI-RADS MRI descriptors.

Objective. To investigate whether fasciitis is histopathologically demonstrable in patients with dermatomyositis (DM), and to analyze the process of inflammatory progression in myopathy accompanying DM.Methods. STIR or fat-suppressed T2-weighted magnetic resonance imaging (MRI) and en bloc biopsy were performed in 14 patients with newly diagnosed adult-onset DM. The severity of inflammatory cell infiltration around the fascial and intramuscular small blood vessels was evaluated using the total vascular inflammation score (TVIS).Results. In all patients, MRI revealed abnormal hyperintensity in the fascia and in marginal sites of the muscle, predominantly over central sites. En bloc biopsy revealed the presence of fasciitis in most of the patients, as shown by inflammatory infiltrates around the fascial small blood vessels. In those patients who underwent en bloc biopsy earlier than 2 months after the appearance of muscle symptoms, the TVIS of the fascia was significantly higher than the TVIS of the muscle. In contrast, in those patients who underwent en bloc biopsy >2 months after muscle symptom onset, the TVIS of the fascia did not differ significantly from the TVIS of the muscle. Conclusion.Fasciitis was histopathologically demonstrated in patients with newly diagnosed adultonset DM as early as 2 months after the onset of muscle symptoms. These results indicate that fasciitis is a common lesion of DM and suggest that the fascial microvasculature is the primary site of inflammatory cell infiltration in DM. Fasciitis may contribute to muscle symptoms in patients with DM without myositis.

A combination of morphologic criteria, particularly lesion shape/margin and internal heterogeneity, and kinetic information is useful for differentiating benign and malignant lesions.

Purpose: The purpose of this study was to assess the potential role of diŠusion-weighted imaging (DWI) using low and high b-values to detect rectal cancer.Methods: The subjects were 15 patients diagnosed endoscopically with rectal cancer (m in 1 patient, sm in 0, mp in 3, ss in 7, se in 1, a in 3) and 20 patients diagnosed endoscopically with colon cancer and no other lesions (control group). Magnetic resonance imaging was performed using a 1.5T system. DWI was performed in the axial plane using echo planar imaging sequence (repetition time W echo time 1200 W 66,ˆeld of view 306×350 mm, reconstruction matrix 156×256, pixel size 2.0×1.4×8.0 mm) and acquired with 2 b-values (50 and 800 s W mm 2 ). Low and high b-value DW images were analyzed visually. A lesion was positive by detection of a focal area of high signal in the rectum in high b-value images. The apparent diŠusion coe‹cient (ADC) values of areas of high signal in high b-value images were calculated from the low and high b-value images.Results: High b-value images enabled visualization of all 15 rectal cancers. In the control group, 13 cases were classiˆed as negative and 7 cases as positive for rectal cancer. Sensitivity for detection of rectal cancer was 100z (15 W 15), and speciˆcity was 65z (13 W 20). The mean ADC values in 7 patients with false-positive lesions and in 15 patients with rectal cancer were 1.374×10 -3 mm 2 W s (standard deviation [SD]: 0.157) and 1.194×10 -3 mm 2 W s (SD: 0.152), respectively (P＝0.026).Conclusion: DWI with low and high b-values may be used to screen for rectal cancer.

Osteoid osteomas in younger patients tend to be associated with more extensive peritumoral edema.

Background: Although oxidative stress by accumulation of reactive oxygen species (ROS) in diabetes has become evident, it remains unclear what genes, involved in redox balance, would determine susceptibility for development of atherosclerosis in diabetes. This study evaluated the effect of genetic polymorphism of enzymes producing or responsible for reducing ROS on coronary artery calcification in type 2 diabetes (T2D).