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Objective The aim of this study was to determine the added value of high-resolution diffusion-weighted imaging (DWI) to T2-weighted imaging (T2WI) for evaluation of extramural tumor invasion (EMTI) in patients with primary rectal cancer. Methods Seventy-eight patients who had undergone 3.0-T magnetic resonance imaging including DWI (b = 0, 1000 s/mm2, 2 mm iso-voxel) and subsequent surgery were included. Two blinded radiologists independently read the T2WI first and then the combined DWI set. They recorded their confidence level using a 5-point scale. The diagnostic accuracy was calculated by receiver operating characteristic curve analysis based on the histopathological results as the reference. Results The study population consisted of EMTI positive (n = 44) and negative (n = 34). The area under the curve was not significantly increased after adding DWI to T2WI (reader 1, 0.868-0.856, P = 0.5618; reader 2, 0.848-0.865, P = 0.4539). Conclusion Adding DWI to T2WI showed no additional diagnostic value for the evaluation of EMTI in patients with primary rectal cancer.

Objective The aim of the study was to compare the diagnostic performance of model-based iterative reconstruction (MBIR), adaptive statistical iterative reconstruction (ASIR), and filtered back projection (FBP) on submillisievert low-dose computed tomography (LDCT) for detecting hepatic metastases. Methods Thirty-eight patients having hepatic metastases underwent abdomen CT. Computed tomography protocol consisted of routine standard-dose portal venous phase scan (120 kVp) and 90-second delayed low-dose scan (80 kVp). The LDCT images were reconstructed with FBP, ASIR, and MBIR, respectively. Two readers recorded the number of hepatic metastases on each image set. Results A total of 105 metastatic lesions were analyzed. For reader 1, sensitivity for detecting metastases was stationary between FBP (49%) and ASIR (52%, P = 0.0697); however, sensitivity increased in MBIR (66%, P = 0.0035). For reader 2, it was stationary for all the following sets: FBP (65%), ASIR (68%), and MBIR (67%, P > 0.05). Conclusions The MBIR and ASIR showed a limited sensitivity for detecting hepatic metastases in submillisievert LDCT.

The purpose of this study was to assess the usefulness of magnetic resonance (MR) arthrography of the glenohumeral joint in the diagnosis of adhesive capsulitis.MR arthrography of the glenohumeral joint was performed in 16 patients with arthroscopically proven adhesive capsulitis and 11 controls. Thickness of the joint capsule and synovium, filling ratio of the fluid-distended axillary recess to the posterior joint cavity, and a width of the rotator cuff interval were measured by 2 musculoskeletal radiologists. The measurements of those parameters for the patients with adhesive capsulitis and the controls were compared. Interobserver variability for the measurements of each parameter was calculated.The mean thickness of the joint capsule and synovium was 2.97 mm in patients with adhesive capsulitis and 1.86 mm in controls (P0.001). The mean filling ratio of the fluid-distended axillary to the posterior joint cavity was 0.51 in patients with adhesive capsulitis and 0.82 in controls (P = 0.004). The mean width of the rotator cuff interval was 7.45 mm in patients with adhesive capsulitis and 8.48 mm in controls (P0.05). Intraclass correlation coefficient for interobserver variability showed good agreement (95% CI; 0.72-0.95).On MR arthrography, thickening of the joint capsule and synovium and diminished filling ratio of the axillary recess to posterior joint cavity appeared to be useful diagnostic criteria for the diagnosis of adhesive capsulitis of the shoulder.

Objective To compare the diagnostic performance of adaptive statistical iterative reconstruction applied low-dose computed tomography (CT) (LDCT) with that of the standard-dose CT (SDCT) for local recurrence in patients with stomach cancer. Methods Seventy-nine consecutive patients who had undergone surgical resection for stomach cancer were enrolled. To monitor recurrence, SDCT (120 kilovolt peak [kVp], 200mAs) had been performed. The LDCT (120 kVp, 100 mA s) was taken, and images were reconstructed with 4 levels of adaptive statistical iterative reconstruction (ASIR) blending (0%, 30%, 50%, and 70%). Two blinded radiologists recorded the diagnostic confidence scores for local recurrence in each data set using a 5-point scale. Endoscopic biopsy results served as the reference standard. Receiver operating characteristic (ROC) curve analysis was used to calculate the diagnostic performance. Results The diagnostic performance of LDCT with variable ASIR blending ratios was comparable to that of SDCT (area under ROC curve, 0.727-0.734, 0.687, respectively, P > 0.05). Conclusions The diagnostic performance of ASIR applied LDCT is comparable to that of SDCT.

Objective The aim of this study was to compare the accuracy of transvaginal US (TVUS), CT, and MRI in detecting deep myometrial invasion in endometrial carcinoma. Materials and methods Twenty-six patients with endometrial carcinoma were evaluated with TVUS, CT, and MRI. The depth of myometrial invasion was estimated in each examination. The invasion depth was categorized into no/superficial and deep and was compared to surgical and pathologic findings. Results At pathologic examination, the depth of myometrial invasion was no/superficial in 16 patients and deep in 10. The accuracy/sensitivity/specificity of TVUS, CT, and MRI in detecting deep myometrial invasion were 69/50/81, 61/40/75, and 89%/90%/88%, respectively. The sensitivity and accuracy of MRI in detecting deep myometrial invasion were significantly higher than those of TVUS and CT (p = 0.049 for both sensitivity and accuracy). Conclusion We recommend MRI instead of CT or TVUS for the evaluation of the depth of myometrial invasion in endometrial carcinoma.

We report imaging findings of renal matrix stones in a patient with congenital ureteropelvic junction obstruction associated with urinary tract infection. The stones were composed of a calcified center and a non-calcified peripheral matrix that was slightly high attenuated on CT and nonshadowing on US.