Prebiopsy biparametric MRI: differences of PI-RADS version 2 in patients with different PSA levels.

AIM: To validate the diagnostic accuracy of Prostate Imaging-Reporting and Data System (PI-RADS) version 2 in detecting clinically significant prostate cancer (csPCa, Gleason score ≥7) on prebiopsy biparametric MRI (bpMRI) in patients with different prostate-specific antigen (PSA) levels. MATERIALS AND METHODS: This retrospective study included 184 patients who underwent prebiopsy bpMRI followed by transrectal ultrasonography-guided biopsy between June 2015 and February 2017. Reader 1 performed a combination of systematic and targeted biopsy with cognitive fusion after reviewing bpMRI and reader 2 reviewed the bpMRIs retrospectively. PI-RADS categories 4 and 5 were considered positive, and the results of the biopsy were considered the reference standard. Diagnostic performance of PI-RADS of bpMRI was evaluated in two PSA groups with a PSA cut-off level of 10 ng/ml and compared to PSA and the PSA density using receiver operating characteristics (ROC) curve analysis. RESULTS: csPCa was diagnosed in 24 of 123 patients (19.5%) and 26 of 61 patients (42.6%) in the low and high PSA groups, respectively. A PI-RADS v2 category by either readers 1 or 2 had a significantly better performance to detect csPCa than PSA in both PSA groups. In the high PSA group, only one csPCa was missed by reader 2, but none by reader 1. In the low PSA group, readers 1 and 2 were unable to detect seven and five of the 24 csPCas, respectively. CONCLUSION: Prebiopsy bpMRI has good performance for detecting csPCa in the high PSA group but may miss small-volume csPCa in the low PSA group.

Uterine cervical carcinoma: a comparison of two- and three-dimensional T2-weighted turbo spin-echo MR imaging at 3.0 T for image quality and local-regional staging.

OBJECTIVE: To compare three-dimensional (3D) T2-weighted turbo spin-echo (TSE) with multiplanar two-dimensional (2D) T2-weighted TSE for the evaluation of invasive cervical carcinoma. METHODS: Seventy-five patients with cervical carcinoma underwent MRI of the pelvis at 3.0 T, using both 5-mm-thick multiplanar 2D (total acquisition time = 12 min 25 s) and 1-mm-thick coronal 3D T2-weighted TSE sequences (7 min 20 s). Quantitative analysis of signal-to-noise ratio (SNR) and qualitative analysis of image quality were performed. Local-regional staging was performed in 45 patients who underwent radical hysterectomy. RESULTS: The estimated SNR of cervical carcinoma and the relative tumour contrast were significantly higher on 3D imaging (P < 0.0001). Tumour conspicuity was better with the 3D sequence, but the sharpness of tumour margin was better with the 2D sequence. No significant difference in overall image quality was noted between the two sequences (P = 0.38). There were no significant differences in terms of the diagnostic accuracy, sensitivity, and specificity of parametrial invasion, vaginal invasion, and lymph node metastases. CONCLUSION: Multiplanar reconstruction 3D T2-weighted imaging is largely equivalent to 2D T2-weighted imaging for overall image quality and staging accuracy of cervical carcinoma with a shorter MR data acquisition, but has limitations with regard to the sharpness of the tumour margin.

Fraudulent retouching of digital radiographic images--a potential risk.

AIM: To determine whether radiologists can recognize images retouched to include sham lesions. MATERIALS AND METHODS: Ten representative key images were selected of aortic dissection, hepatocellular carcinoma, renal cell carcinoma, colon cancer, liver metastasis, hepatic cyst, gallbladder stones, splenic artery aneurysm, adrenal adenoma, and stomach cancer from abdominal computed tomography (CT) imaging performed in 2008. Five of the key images were replaced with retouched images using image-editing software. The time to complete retouching was recorded for each image. Radiologists were requested to make a diagnosis for the 10 images, and were then asked to identify possible retouched images. The time taken to reach a decision in each case was recorded. Thirty radiologists (13 residents and 17 attending radiologists) participated as reviewers. RESULTS: The time to complete retouching was 15.2±3.15 min. None of the reviewers recognized that some images were retouched during diagnosis. The rate of correct diagnosis was 90% (range 71.7-100%). After reviewers were informed of possible image retouching, the detection rate of retouched images was 50% (40-58.3%). This rate was statistically the same as random choice (p=0.876). There was no significant difference between residents and attending radiologists in the detection rate of retouched images (p=0.786). The time to diagnosis and the time to detection of the retouched images were 15 (14-17) and 6 (5-7) min, respectively. CONCLUSION: Digital images can be easily retouched, and radiologists have difficulty in identifying retouched images. Radiologists should be aware of the potential fraudulent use of retouched images.

Correlation of portal venous velocity and portal venous flow with short-term graft regeneration in recipients of living donor liver transplants.

BACKGROUND: To evaluate the correlation of postoperative portal venous velocity (PVV) and portal venous flow (PVF) with the degree of short-term graft regeneration in recipients of living donor liver transplantation (LDLT). MATERIALS AND METHODS: Between August 2005 and April 2006, we performed 44 adult-to-adult LDLTs with right-lobe grafts, of whom 31 recipients were included in this study. Doppler ultrasonography was used to measure PVV (cm/s) and PVF (mL/min) on postoperative days (POD) 1, 3, and 5 or 6. Portal venous velocity index (PVI) was defined as the ratio of PVV to graft weight (GW), and portal flow volume index (PFI) as the ratio of PVF to GW. Graft regeneration rate (GRR), defined as the ratio of the volume of regenerated graft to GW, was estimated by dividing computed tomography volumetry at POD 7 by GW measured after retrieval of the graft. We analyzed the relationship between GRR and PVV, PVF, PVI, and PFI. RESULTS: GW ranged between 528 g and 1040 g (mean = 735 g) and GRR ranged between 118% and 278% (mean = 172%). Although neither PVV nor PVF correlated with GRR, PVI and PFI at POD 1 (P = .009) and PFI at POD 5 or 6 (P = .012) significantly correlated with GRR at POD 7. CONCLUSION: PVI and PFI at POD 1 are useful indicators to predict short-term graft regeneration in recipients of LDLT.

Ten-Year Experience With Bowel Transplantation at Seoul St. Mary's Hospital.

A retrospective review of intestinal transplantation (ITx) at Seoul St. Mary's Hospital was made by collecting clinical data over the past 10 years. Fifteen consecutive cases from 2004 were analyzed. Five children and 10 adults (6 months to 69 years of age) were included. Primary diseases in adults included 4 mesenteric vessel thromboses, 2 strangulations, and 1 each of visceral myopathy, malignant gastrointestinal stromal tumor (GIST), mesenteric lymphangiectasis, and injury. Pediatric cases involved 2 Hirschsprung disease, 2 visceral myopathy, and 1 necrotizing enterocolitis. Three of 7 stomas were closed using a serial transverse enteroplasty procedure before transplantation. The ITx were performed using 3 living-donor Itx, 12 deceased-donor ITx, 14 isolated Itx, and 1 modified multivisceral transplantation. Daclizumab, basiliximab, alemtusumab, or basiliximab with rabbit antithymocyte globulin (rATG) was used for the induction; tacrolimus monotherapy was used as the basic maintenance immunosuppressant; and m-TOR inhibitor was used for renal dysfunction patients. Seven cases of acute cellular rejection were treated with rATG. Three cases of antibody-mediated rejection were treated with rituximab alone or with rituximab and bortezomib combination. There were 4 cases of early mortality within 6 months after Itx. Causes of death were declamping shock, cardiac tamponade with acute cellular rejection, dysmotility, and sepsis. Surgical complications consisted of 1 feeding jejunostomy displacement, and a minor leakage at a colo-colostomy site. One-year survival of the patient and graft was 73.33% (Kaplan-Meier survival curve). Although the total number of ITx is small, its social impact has been remarkable in changing the related laws and reimbursement policy in Korea.

Kaposi's sarcoma involving a transplanted kidney, ureter and urinary bladder: ultrasound and CT findings.

We report the imaging findings in a case of Kaposi's sarcoma involving a transplanted kidney, ureter and urinary bladder. Ultrasound and CT demonstrated multiple nodular masses in the pelvis of the transplanted kidney, ureter and bladder. The masses enhanced well on CT following i.v. contrast medium.

CT and MR diagnoses of intestinal ischemia.

CT and MR imaging have an important role in establishing the diagnosis of mesenteric ischemia. However, without specific signs such as thromboembolism in the mesenteric vessel, intramural or portal venous gas, and the absence of bowel wall enhancement, mesenteric ischemia can be confused with inflammatory or neoplastic gastrointestinal diseases. Arterial or venous occlusion or low-flow state are the main direct causes of mesenteric ischemia. Delayed diagnosis in equivocal cases can be avoided through an understanding of the patholophysiological aspects of mesenteric ischemia as they occur in a variety of other conditions, including: thromboembolism, bowel obstruction, neoplasm, vasculitis, inflammatory diseases, trauma, and drug or radiation therapy.

Case report. Lipomatous haemangiopericytoma (fat-forming solitary fibrous tumour) involving the perineum: CT and MRI findings and pathological correlation.

Lipomatous haemangiopericytoma (a fat-forming solitary fibrous tumour) is a rare soft-tissue tumour histologically characterized by haemangiopericytomatous vasculature and the presence of mature adipocytes. We report the CT and MRI findings of a case of lipomatous haemangiopericytoma involving the perineum. CT showed a well-circumscribed soft-tissue density mass containing a small area of fat density and a punctuate calcification. On MR images, the mass was mostly isointense to the muscle on T(1) weighted images, with heterogeneous signal intensity on T(2) weighted images, and showed strong contrast enhancement except for the fatty and dense collagenous components. This is the first case report of imaging findings of a lipomatous haemangiopericytoma in the radiological literature. Although rare, lipomatous haemangiopericytoma should be considered as a differential diagnosis of fat-containing, hypervascular soft-tissue tumours with variable signal intensity on T(2) weighted images.

Case report: Ovarian cavernous haemangioma presenting as a heavily calcified adnexal mass.

Haemangioma is an extremely rare tumour of the ovary. We describe the CT and MRI findings of a heavily calcified ovarian haemangioma in a 69-year-old woman presenting with adnexal torsion. CT showed a well-circumscribed mass with extensive punctate calcifications, located posterior to the uterus. MR images showed dark signal intensities of the mass on both T(1) and T(2) weighted images, with poor enhancement of the mass on contrast-enhanced T(1) weighted images. MR images also demonstrated a beak-like protrusion from the adnexal mass, representing the adnexal torsion. This is the first case report of a heavily calcified ovarian haemangioma in the English literature. Although rare, ovarian haemangioma should be included in the differential diagnosis of a heavily calcified adnexal mass.

MRI features of ovarian fibromas: emphasis on their relationship to the ovary.

AIM: To evaluate the magnetic resonance (MR) imaging features of ovarian fibromas, emphasizing the presence and shape of the ovary on the same side of the fibroma. MATERIALS AND METHODS: MR images from 23 patients with 24 histologically proven ovarian fibromas were reviewed by two radiologists. Eleven were pre-menopausal and 12 were postmenopausal. The presence and shape of the ovarian tissue on the same side of the fibroma were evaluated on T2-weighted MR images. RESULTS: In 11 (46%) of the 24 ovarian fibromas, the ipsilateral ovary was detected on T2-weighted images. The ovary was crescent-shaped along the periphery of the fibroma in six (55%) of 11 fibromas and had a normal, oval shape in five (45%). Of these five tumours, the ovary was connected to the fibromas by a pedicle-like structure in three and was closely attached to the periphery of the fibromas in two. The ipsilateral ovary was detected in 10 (83%) of 12 fibromas in pre-menopausal patients, and in one (8%) of 12 fibromas in postmenopausal patients. There was a statistically significant difference (p=0.001) in the presence of detectable ipsilateral ovary between pre-menopausal and postmenopausal women. CONCLUSIONS: Detection of the remaining ovary on the same side as the fibroma is not unusual on MRI, especially in pre-menopausal women, and the shape of the ovary may be normal in cases of fibromas with exophytic growth from the periphery of the ovary.

Chilaiditi syndrome caused by Fitz-Hugh-Curtis syndrome: multidetector CT findings.

Chilaiditi syndrome is a condition in which the colon or small intestine is interposed temporarily or permanently between the liver and the diaphragm. Usually, it is an asymptomatic and incidental radiographic finding, but it may be a potential source of abdominal problems, ranging from intermittent mild abdominal pain to acute intestinal obstruction. We report multidetector computed tomographic findings of a case of Chilaiditi syndrome presenting as small bowel obstruction due to hepatodiaphragmatic interposition of the ileal loop, which was entrapped by adhesive bands caused by Fitz-Hugh-Curtis syndrome.

Gallbladder wall thickening: MR imaging and pathologic correlation with emphasis on layered pattern.

The aim of this study was to correlate MR findings of gallbladder wall thickening with pathologic findings on the basis of the layered pattern and to evaluate the diagnostic value of MR imaging in gallbladder disease. We retrospectively evaluated the source images of HASTE sequences for MR cholangiography in 144 patients with gallbladder wall thickening. The layered pattern of thickened wall was classified into four patterns. Type 1 shows two layers with a thin hypointense inner layer and thick hyperintense outer layer. Type 2 has two layers of ill-defined margin. Type 3 shows multiple hyperintense cystic spaces in the wall. Type 4 shows diffuse nodular thickening without layering. MR findings of a layered pattern of thickened gallbladder were well correlated with histopathology. Chronic cholecystitis matched to type 1, acute cholecystitis corresponded to type 2, adenomyomatosis showed type 3, and the gallbladder carcinomas showed type 4. All four layered patterns were associated with PPV of 73% or greater, sensitivity of 92% or greater and specificity of 95% or greater. Our results indicate that MR findings of gallbladder wall thickening are characteristic in each entity and correlate well with pathologic findings. The classification of the layered pattern may be valuable for interpreting thickened gallbladder wall.

Pedunculated exogastric leiomyoblastoma presenting as a wandering abdominal mass.

We report the imaging findings in a case of pedunculated exogastric leiomyoblastoma presenting as a wandering abdominal mass. Ultrasound and computed tomography showed a large, mixed solid and cystic mass in the peritoneal cavity. Computed tomography clearly showed that the mass was connected to the stomach by a narrow stalk. Small bowel follow-through showed subtle extrinsic indentation of the gastric body. The mass wandered from the right to the left side of the peritoneal cavity during various radiologic examinations.

Gastrointestinal leiomyoma and leiomyosarcoma: CT differentiation.

PURPOSE: Our goal was to evaluate CT efficacy in differentiating gastrointestinal leiomyoma and leiomyosarcoma. METHOD: We retrospectively reviewed CT scans of 45 patients (21 men, 24 women, mean age 55 years) with surgically proven gastrointestinal leiomyomas (n = 21) and leiomyosarcomas (n = 24) with respect to size, contour, enhancing pattern, mesenteric fat infiltration, calcification, ulceration, regional lymphadenopathy, direct invasion, distant metastasis, and growth pattern after visual inspection by two radiologists in agreement. On the basis of these CT features, subjective diagnosis was also categorized into three groups (Group I: probably benign, Group II: probably malignant, Group III: diagnostic malignant). The results were compared with the final histopathologic diagnosis. RESULTS: In addition to the features of direct invasion and distant metastasis suggesting diagnostic malignancy, the CT features favoring malignancy with statistical significance included larger size (> 5 cm), lobulated contour, heterogeneous enhancement, mesenteric fat infiltration, ulceration, regional lymphadenopathy, and exophytic growth pattern (p < 0.005). However, calcification was not significant in differentiating the two entities (p = 0.25163). A subjective analysis revealed 89% sensitivity, 85% specificity, and 87% accuracy for diagnosis of leiomyosarcoma. CONCLUSION: CT features are useful in differentiating leiomyoma and leiomyosarcoma in gastrointestinal tract.

Nodular regenerative hyperplasia of the liver in Budd-Chiari syndrome: CT and MR features.

We report the imaging findings of spiral computed tomography (CT), magnetic resonance (MR) imaging, and MR angiography in a patient with nodular regenerative hyperplasia of the liver associated with Budd-Chiari syndrome. Spiral CT showed multiple enhancing nodules during the hepatic arterial and portal venous phases. MR images showed multiple hyperintense nodules on T1-weighted images and hypointense or isointense nodules on T2-weighted images. MR angiography showed thrombotic occlusion of three hepatic veins, suggesting Budd-Chiari syndrome.

Modified small-bowel follow-through: use of methylcellulose to improve bowel transradiance and prepare barium suspension.

PURPOSE: To evaluate the efficacy of barium suspension prepared in methylcellulose (MC) in modified small-bowel follow-through (SBFT). MATERIALS AND METHODS: The authors evaluated 155 patients who underwent modified SBFT with oral administration of MC after ingesting barium suspension. Of these patients, 52 received 40% suspension in MC, 46 received 40% suspension in water, and 57 received 70% suspension in water. Patients were divided into normal (n = 74) and abnormal (n = 81) groups according to the final results. The image quality, transit time to the cecum, and time to and frequency of flocculation were compared for both groups. RESULTS: In the normal group, the quality of the images in patients receiving 40% suspension in MC or 70% suspension in water was superior to that of images in patients receiving 40% suspension in water. In the abnormal group, the best image quality was achieved for the patients who received 40% suspension in MC. In the normal group, the difference in transit time between the three preparations was not substantial. In the abnormal group, however, the 40% suspension in MC showed the fastest transit time. Use of the 40% suspension in MC helped lower the frequency of flocculation in the normal group. CONCLUSION: Use of 40% barium suspension in MC is effective for improving the image quality in modified SBFT.

CT features of metastatic linitis plastica to the rectum in patients with peritoneal carcinomatosis.

OBJECTIVE: We examined the CT features of 22 patients with metastatic linitis plastica to the rectum. CONCLUSION: Metastatic linitis plastica to the rectum should be considered when CT shows a long segment of circumferential rectal wall thickening, especially in patients with peritoneal carcinomatosis from gastric cancer. In such patients, CT helps avoid unnecessary extensive surgery.

Usefulness of CT in patients with intestinal obstruction who have undergone abdominal surgery for malignancy.

OBJECTIVE: The purpose of this study was to evaluate the usefulness of CT in determining the causes of intestinal obstruction in patients who have undergone abdominal surgery for malignancy. MATERIALS AND METHODS: We analyzed the CT scans of 55 patients with benign (n = 26) or malignant (n = 29) intestinal obstruction that developed after abdominal surgery for malignancy. After calculating the diagnostic accuracy of interpretations by three radiologists, we compared CT findings for benign and malignant intestinal obstructions with respect to peritoneal involvement patterns and other ancillary findings. Multivariate logistic regression analysis was used to determine the diagnostic performance of CT in revealing causes of obstruction. RESULTS: Diagnostic accuracies of the three radiologists were 67%, 75%, and 78%. CT findings indicating malignant obstruction were a mass at the site of obstruction or prior surgery, lymphadenopathy, or an abrupt transition zone and irregular bowel wall thickening at obstructed sites (p < .05). Conversely, the chance for benign obstruction increased when CT revealed mesenteric vascular changes, a large amount of ascites, or a smooth transition zone and smooth bowel wall thickening at the obstructed site (p < .05). With multivariate logistic regression analysis using two variables (a mass at the site of obstruction or prior surgery and lymphadenopathy), we calculated the overall accuracy of CT as 84% (46/55 patients). CONCLUSION: CT is useful in differentiating benign from malignant intestinal obstructions in patients who have undergone abdominal surgery for malignancy. However, CT has limitations in patients not having a demonstrable peritoneal mass.