Computed tomography findings of intersigmoid hernia

Purpose: To evaluate the computed tomography findings of intersigmoid hernias. Material and methods: Between April 2010 and March 2018, 7 patients who were surgically diagnosed with intersigmoid hernia in 3 institutions were enrolled in this study. Two radiologists evaluated imaging findings for the herniated small bowel, the distance between the occlusion point and bifurcation of the left common iliac artery, and the anatomic relationship with adjacent organs. Results: All patients were male, and their mean age (standard deviation, range) was 61.0 (13.5, 36-85) years. The mean size of the bowel loops was 5.2 (1.3, 4.0-8.3) cm in the caudal direction, 3.6 (0.8, 2.5-5.1) cm in the lateral, and 3.4 (0.6, 2.5-4.7) cm in the anterior-posterior direction. The volume was 37.9 (27.8, 15.6-103.0) cm3 approximated by an ellipse, and 24.0 (17.7, 9.9-65.6) cm3 approximated by a truncated cone. The obstruction point was located 3.6 (0.6, 2.8-4.7) cm inferior to the bifurcation of the left common iliac artery. In all cases, the small bowel ran under the point at which the inferior mesenteric vessels bifurcated to the superior rectal vessels and the sigmoid vessels and formed a sac-like appearance between the left psoas muscle and the sigmoid colon. The ureter ran dorsal to the point of the bowel stenosis, and the left gonadal vein ran outside the small bowel loops. Conclusions: All cases showed common imaging findings, which may be characteristic of men's intersigmoid hernia. In addition, the fossa's position was lower, and the size was larger than in the previous study, which may be a risk factor

Clinical Outcomes and Prognostic Factors Associated with Survival after Balloon-occluded Retrograde Transvenous Obliteration of Gastric Varices

We evaluated clinical outcomes and prognostic factors associated with survival after balloon-occluded retrograde transvenous obliteration (B-RTO) of gastric varices in patients with portal hypertension. Of 50 patients with gastric varices who underwent B-RTO, 46 (94.0%) patients in whom B-RTO was technically successful were reviewed retrospectively. Gastric and esophageal varices after B-RTO were evaluated by contrast-enhanced computer tomography and endoscopy, respectively. Liver function parameters and Child-Pugh scores were estimated before and at 1 year after B-RTO. The cumulative survival rate was calculated, and univariate and multivariate analyses were used to assess the prognostic factors. No major complications occurred in any of the patients following B-RTO and no recurrence or bleeding of gastric varices was noted. Of the 42 patients who were followed up for the progression of esophageal varices, 13 (31.0%) had worsened varices and of these, 6 (14.3%) showed bleeding. Prothrombin activity had significantly improved at 1 year after B-RTO, although there were no changes in other liver function parameters. The overall cumulative survival rates at 1, 3, and 5 years after B-RTO were 91.6%, 70.9%, and 53.6%, respectively. Multivariate analysis identified the occurrence of advanced hepatocellular carcinoma (HCC) during the observation period as a prognostic factor for survival (hazard ratio = 4.1497, 95% CI = 1.32314-13.0319, P = 0.0148). B-RTO of gastric varices is an effective treatment ensuring lower recurrence and bleeding rates; however, these patients require careful observation for progression of esophageal varices. The management of HCC is crucial for achieving long-term survival after B-RTO

Diagnostic Ability of Diffusion-weighted Magnetic Resonance Imaging to Discriminate Ampullary eoplasms: A Preliminary Study of 15 Cases

We assessed the diagnostic capability of diffusion-weighted magnetic resonance imaging (DWI) to predict the histological diagnosis of ampullary lesions to resolve the diagnostic uncertainty of endoscopic biopsy for ampullary neoplasms. From January 2009 to August 2011, we performed DWI using b values of 0 and 1000s/mm2 for 15 patients with a histological diagnosis of ampullary lesion (adenocarcinoma, n = 8; adenoma, n = 4; hyperplasia, n = 3). We compared the signal intensities (determined by comparing signal intensities of ampullary lesions and rating them as markedly hyperintense, hyperintense, or hypo-to-isointense relative to the duodenal wall) and the apparent diffusion coefficient (ADC, × 10-3 mm2/s) values of the ampullary lesions on DWI among the three groups based on the histological diagnosis. Values are expressed as median (range). The cancer-group lesions showed a significantly higher signal intensity than either adenoma or hyperplasia (markedly hyperintense/hyperintense/hypo-to-isointense; adenocarcinoma, 7/1/0; adenoma, 0/4/0; hyperplasia, 0/0/3; P < 0.005). The ADC values were significantly lower in adenocarcinoma at 1.46 (0.83-1.63) than in either adenoma at 2.14 (1.92-2.37) or hyperplasia at 2.06 (1.88-2.53) (P < 0.005). In addition, the ADC values in the malignant group (adenocarcinoma) were significantly lower than those in the benign groups (adenoma and hyperplasia) (P < 0.001). The findings suggested that DWI could contribute significantly to accurate preprocedural diagnosis of ampullary lesions

C-arm Cone-beam CT-guided Needle Biopsies through the Erector Spinal Muscle for Posterior Thoracic Pulmonary Lesions

This study investigated retrospectively the diagnostic yield and complication rate of transthoracic needle biopsies for posterior thoracic pulmonary lesions using C-arm cone-beam computed tomography （CBCT）. The risk factors for pulmonary hemorrhage were evaluated. Our study included 113 patients with 113 posterior pulmonary lesions （mean longest diameter: 30.6mm, and mean depth: 4.7mm） through the erector spinal muscles using a 19/20-gauge coaxial system. The diagnostic performances of procedures for malignant lesions and the incidence of complications after biopsies were also assessed. The patient-related and procedure-related variables were investigated. Risk factors for pulmonary hemorrhage were analyzed with a multivariate logistic regression analysis. Findings revealed 99 malignant, 13 benign, and one intermediate lesion. Sensitivity, specificity, and diagnostic accuracy rates were 100％ （99/99）, 92.3％ （12/13）, and 99.1％ （111/112）, respectively. Air embolization, hemothorax, hemoptysis, pneumothorax, and pulmonary hemorrhage, occurred in 0, 2, 12, 48, and 70 procedures. The averaged spinous process-pleura depth and the traversed lung parenchyma depth achieved by the introducer needles were 54.2mm and 27.4mm, respectively. The needle position at the pleural puncture site within the intercostal space was in middle （31％） and inferior （69％） areas. The incidence of pulmonary hemorrhage was significantly higher in smaller lesions （p＝0.001）. Manual evacuation was performed in five procedures for patients with pneumothorax. The chest tube placement （trocar＞8 Fr） was performed in two procedures in patients with hemothorax and pneumothorax. In conclusion, the biopsy method with a posterior intercostal approach for posterior thoracic pulmonary lesions yielded high diagnostic accuracy and few major complications

Alternative Starting Position for CT Coronary Angiography

We examined whether the superior margin of the left main bronchus is the best landmark for the starting position of computed tomography coronary angiography（CTCA）. We retrospectively evaluated 693 consecutive CTCAs. From the scout scanogram, the superior margin of the left main bronchus was noted. The relationships among and distance between the superior margin of the left main bronchus and the left coronary system were analyzed. The superior margin of the left main bronchus extended caudally to the superior margin of the left coronary system in 13 patients（1.9％）. The addition of 1cm to the superior margin of the left main bronchus kept it caudal to the superior margin of the left coronary system in only one patient（0.1％）. On the scout scanogram, 1cm above the superior margin of the left main bronchus is the most appropriate starting position for CTCA

Assessment of Hepatocellular Carcinoma Ablation Margins Using Fused Pre-ablation Hepatobiliary Phase and Post-ablation Unenhanced T1-weighted Images

This study retrospectively investigated the value of fusing a pre-ablation hepatobiliary phase（HBP）series and post-ablation unenhanced T1-weighted images（T1WIs）to evaluate the treatment effectiveness of radiofrequency ablation for hepatocellular carcinoma（HCC）. Predictors of local tumor progression（LTP）were also identified. Our study comprised 47 patients with 88 HCCs（＞2 years follow up）who underwent pre-ablation gadoxetate disodium-enhanced magnetic resonance imaging and post-ablation T1-weighted imaging. For the new assessment, pre-ablation HBP series and post-ablation T1WIs were fused using a rigid registration and manual correlation, and the ablation margin appearance was classified as ablation margin（＋）, ablation margin zero, ablation margin（−）, or indeterminate（index tumor was invisible）based on the post-ablation T1WIs and fusion images. The minimal ablation margin was measured and clinical factors were investigated to identify other risk factors for LTP, which was observed in 14 tumors. The mean minimal ablation margin was 1.9mm, excluding 5 indeterminate nodules without LTP, and 8 ablation margin-zero HCCs with LTP, with multivariate logistic regression analysis showing that the likelihood of ablation margin＋was inversely proportional to tumor size. The independent risk factors for LTP were not identified, but the cumulative LTP rates（0％ at 1, 2, and 3 years）in 41 ablation margin＋ nodules were significantly lower（P＝0.005）than those（8.8％, 17.6％, and 17.6％ at 1, 2, and 3 years, respectively）in 34 ablation margin-zero nodules. In conclusion, fusion images might show an early therapeutic response of the ablated tumors in the majority of HCC cases