Extramedullary Hematopoiesis: A Forgotten Diagnosis and a Great Mimicker of Malignancy.

ABSTRACT: Radiology errors have been reported in up to 30% of cases when patients have abnormal imaging findings. Although more than half of errors are failures to detect critical findings, over 40% of errors are when findings are recognized but the correct diagnosis or interpretation is not made. One common source of error is when imaging findings from one process simulate imaging findings from another process but the correct diagnosis is not made. This can result in additional imaging studies, unnecessary biopsies, or surgery. Extramedullary hematopoiesis is one of those uncommon disease processes that can produce many imaging findings that may lead to misdiagnosis. The objective of this article is to review the common and uncommon imaging features of extramedullary hematopoiesis while presenting a series of interesting relevant illustrative cases with emphasis on CT.

Baseline 3D-ADC outperforms 2D-ADC in predicting response to treatment in patients with colorectal liver metastases.

OBJECTIVES: To examine the value of baseline 3D-ADC and to predict short-term response to treatment in patients with hepatic colorectal metastases (CLMs). METHODS: Liver MR images of 546 patients with CLMs (2008-2015) were reviewed retrospectively and 68 patients fulfilled inclusion criteria. Patients had received systemic chemotherapy (n = 17), hepatic trans-arterial chemoembolization or TACE (n = 34), and 90Y radioembolization (n = 17). Baseline (pre-treatment) 3D-ADC (volumetric) of metastatic lesions was calculated employing prototype software. RECIST 1.1 was used to assess short-term response to treatment. Prediction of response to treatment by baseline 3D-ADC and 2D-ADC (ROI-based) was also compared in all patients. RESULTS: Partial response to treatment (minimum 30% decrease in tumor largest transverse diameter) was seen in 35.3% of patients; 41.2% with systemic chemotherapy, 32.4% with TACE, and 35.3% with 90Y radioembolization (p = 0.82). Median baseline 3D-ADC was significantly lower in responding than in nonresponding lesions. Area under the curve (AUC) of 3D-ADC was 0.90 in 90Y radioembolization patients, 0.88 in TACE patients, and 0.77 in systemic chemotherapy patients (p < 0.01). Optimal prediction was observed with the 10th percentile of ADC (1006 × 10-6 mm2/s), yielding sensitivity and specificity of 77.4% and 91.3%, respectively. 3D-ADC outperformed 2D-ADC in predicting response to treatment (AUC; 0.86 vs. 0.71; p < 0.001). CONCLUSION: Baseline 3D-ADC is a highly specific biomarker in predicting partial short-term response to treatment in hepatic CLMs. KEY POINTS: • Baseline 3D-ADC is a highly specific biomarker in predicting response to different treatments in hepatic CLMs. • The prediction level of baseline ADC is better for90Y radioembolization than for systemic chemotherapy/TACE in hepatic CLMs. • 3D-ADC outperforms 2D-ADC in predicting short-term response to treatment in hepatic CLMs.

Invasive Intraductal Papillary Mucinous Neoplasms: CT Features of Colloid Carcinoma Versus Tubular Adenocarcinoma of the Pancreas.

OBJECTIVE. The purpose of this study is to compare the CT features of colloid carcinoma and tubular adenocarcinoma of the pancreas arising in association with intraductal papillary mucinous neoplasms (IPMNs). MATERIALS AND METHODS. The preoperative CT images of 85 patients with histopathologically proven IPMNs and associated invasive adenocarcinoma located next to each other were retrospectively reviewed. Twenty-nine patients (34.1%; 19 men and 10 women; mean [± SD] age, 68.0 ± 9.5 years) had invasive colloid carcinoma, and 56 patients (65.9%; 31 men and 25 women; mean age, 70.8 ± 10.6 years) had invasive tubular adenocarcinoma. We compared the following CT features between the two groups: IPMN type, main pancreatic duct (MPD) and common bile duct diameters, diameter and characteristics of the largest cystic lesion for branch duct and mixed-type IPMNs, presence of an extracystic or extraductal solid mass next to the cystic lesion or MPD, morphologic features of the upstream MPD in relation to the cystic lesion or solid mass, and presence of a fistula to the adjacent organs. RESULTS. An MPD size of 9.5 mm or greater, a largest cystic lesion diameter of 28 mm or greater, location in the head or neck, septation, calcification, presence of a mural nodule(s) within a cystic lesion or MPD, and presence of a fistula were all more commonly associated with colloid carcinoma. In contrast, presence of an extracystic or extraductal solid mass and an abrupt change in the caliber of the dilated MPD were associated with tubular adenocarcinoma. The best CT feature for differentiating between the two groups was the morphologic features of the upstream MPD in relation to the cystic lesion or solid mass (sensitivity, 81.3%; specificity, 92.3%). CONCLUSION. Preoperative CT is helpful in differentiating two types of invasive carcinoma arising in association with IPMNs. These findings are clinically important because prognosis is better for colloid carcinoma than for tubular adenocarcinoma.

Diagnostic performance of 64-MDCT in detecting ERCP-proven periampullary duodenal diverticula.

AIM: To determine the diagnostic performance of 64-slice multidetector computed tomography (64-MDCT) in detecting periampullary duodenal diverticula. MATERIALS AND METHODS: Medical profiles of 120 endoscopic retrograde cholangiopancreatography (ERCP)-proven patients with (n = 100) and without (n = 20) periampullary duodenal diverticula who had undergone 64-MDCT were retrospectively reviewed. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 64-MDCT in detecting periampullary duodenal diverticula were calculated. Potential factors that might influence the diagnostic performance of 64-MDCT in such patients were also examined. RESULTS: Patients were 60 males and 60 females with the mean age of 68.8 ± 12.7 (27-93) years. Indications of ERCP were common bile duct stricture (n = 62) or stone (n = 41), biliary cholestasis (n = 16) and acute cholangitis (n = 1). The sensitivity, specificity, PPV, and NPV of 64-MDCT in detecting periampullary duodenal diverticula were 76%, 100%, 100%, and 45.5%, respectively. The size of diverticula was the only predictor of 64-MDCT performance, with better results observed in larger (> 20 mm) diverticula. CONCLUSION: 64-MDCT is a highly specific imaging modality in detecting periampullary duodenal diverticula. The diagnostic performance of 64-MDCT increases for larger diverticula.

Clinical and histopathological outcome of cervical and chest MRI involving non-MRI-conditional cardiac pacemakers: a study using sheep models.

AIM: To examine the clinical and histopathological consequences of MRI in sheep implanted with non-MRI-conditional cardiac pacemakers. MATERIALS AND METHODS: Under general anesthesia, active fixation leads of two dual-chamber, non-MRI-conditional cardiac pacemakers (St. Jude Medical and Medtronic) were implanted either at the right ventricular apex or at the right atrium of two male sheep and connected to the V and A channels of the pacemakers, respectively. The generators were placed in cervical subcutaneous pockets. On day 5, both sheep underwent 1.5 T cervical and chest MRI with continuous electrocardiogram monitoring. Obtained sequences were T1-weighted (T1W), T2-weighted (T2W), T2-gradient echo and diffusion weighted (DW). The employed modes were OVO, VOO and VVI for one sheep and OAO, AOO and AAI for the other (unipolar and bipolar configuration of pacing and sensing for both). Battery impedance, pacing lead impedance, intrinsic amplitude and capture thresholds were checked at baseline and after each sequence, as well as 48 h after imaging. Histopathological examination of the cardiac tissue around the lead tip was performed 4 weeks post-imaging. RESULTS: No significant changes in device position or configuration were observed during or after MRI. Clinical outcome was uneventful in both sheep. Minor inflammatory and necrotic changes were reported after histopathological examination of the cardiac tissue around the lead tip. CONCLUSION: 1.5 T MRI of two implanted non-MRI-conditional pacemakers was found safe in terms of device configuration and stability, clinical outcome and cardiac tissue histopathological findings.

Unresectable Intrahepatic Cholangiocarcinoma: Multiparametric MR Imaging to Predict Patient Survival.

Purpose To determine the performance of magnetic resonance (MR) imaging-based tumor metrics for evaluation of response to transarterial chemoembolization (TACE) in patients with unresectable intrahepatic cholangiocarcinoma (ICCA). Materials and Methods Ninety-four patients with unresectable ICCA underwent baseline and follow-up MR imaging after TACE and were followed up until death or end of study duration. Lesions were analyzed for anatomic (Response Evaluation Criteria in Solid Tumors [RECIST] and tumor volume) and functional (viable tumor volume, viable tumor burden, and apparent diffusion coefficient [ADC]) volumetric MR parameters by using semiautomatic software. Response was assessed by using changes in viable tumor volume by using modified RECIST (mRECIST)-derived thresholds (three-dimensional mRECIST), viable tumor burden, and ADC. Overall survival was the primary endpoint. Cox-regression and Kaplan-Meier survival analysis were used. Results Tumor volume did not change after TACE (P = .07) whereas RECIST diameter showed a small change (-2.6%; P = .02). There was an increase in ADC (20.7%) and a decrease in viable tumor volume (-29.3%) and viable tumor burden (-29.1%; P < .001 for all). Higher overall survival was noted among responders by using thresholds of 25% increase in ADC, 66% decrease in viable tumor volume, and 50% decrease in viable tumor burden (log-rank test, P < .05). Hazard ratio for nonresponders by using ADC, three-dimensional mRECIST, and viable tumor burden at multivariable analysis was 2.9 (P = .004), 4.1 (P = .009), and 4.0 (P = .002), respectively. Survival differences were noted for patients who showed response by using all three parameters (ADC, three-dimensional mRECIST, and viable tumor burden) versus those who showed response by using either one or two of these parameters versus those who showed no response (P < .001). Conclusion Changes in volumetric ADC, viable tumor volume, and viable tumor burden at MR imaging provide prognostic information among patients with unresectable ICCA who undergo TACE. © RSNA, 2018 Online supplemental material is available for this article.

Accuracy of apparent diffusion coefficient in differentiating pancreatic neuroendocrine tumour from intrapancreatic accessory spleen.

OBJECTIVES: To evaluate and compare the accuracy of absolute apparent diffusion coefficient (ADC) and normalised ADC (lesion-to-spleen ADC ratio) in differentiating pancreatic neuroendocrine tumour (NET) from intrapancreatic accessory spleen (IPAS). METHODS: Study included 62 patients with the diagnosis of pancreatic NET (n=51) or IPAS (n=11). Two independent reviewers measured ADC on all lesions and spleen. Receiver operating characteristics (ROC) analysis to differentiate NET from IPAS was performed and compared for absolute and normalised ADC. Inter-reader reliability for the two methods was assessed. RESULTS: Pancreatic NET had significantly higher absolute ADC (1.431x10-3 vs 0.967x10-3 mm2/s; P<0.0001) and normalised ADC (1.59 vs 1.09; P<0.0001) compared to IPAS. An ADC value of ≥1.206x10-3 mm2/s was 70.6% sensitive and 90.9% specific for the diagnosis of NET vs. IPAS. Lesion to spleen ADC ratio of ≥1.25 was 80.4% sensitive, and 81.8% specific while ratio of ≥1.29 was 74.5% sensitive and 100% specific in the differentiation. The area under the curve (AUCs) for two methods were similar (88.2% vs. 88.8%; P=0.899). Both methods demonstrated excellent inter-reader reliability with ICCs for absolute ADC and ADC ratio being 0.957 and 0.927, respectively. CONCLUSION: Both absolute and normalised ADC allow clinically relevant differentiation of pancreatic NET and IPAS. KEY POINTS: • Imaging overlaps between IPASs and pancreatic-NETs lead to unnecessary procedures including pancreatectomy. • Uniquely low ADC of spleen allows differentiating IPASs from pancreatic NETs. • Both absolute-ADC and normalised-ADC (lesion-to-spleen ADC-ratio) demonstrate high accuracy in differentiating IPASs from NETs. • Both methods demonstrate excellent inter-reader reliability.

Infrarenal aortic diameter, aortoiliac bifurcation level and lumbar disc degenerative changes: a cross-sectional MR study.

PURPOSE: To examine a possible correlation of infrarenal aortic diameter and aortoiliac bifurcation level with lumbar disc degenerative changes. METHODS: This was a cross-sectional, single-center retrospective study on lumbar magnetic resonance images of patients with low back pain (n = 496). Lumbar disc degenerative changes were reported on the basis of the Pfirrmann grading system and accordingly, patients were grouped as with grade I-II findings (n = 192), with grade III findings (n = 64) and with grade IV-V findings (n = 240). The groups were matched for sex, body mass index and the history of diabetes mellitus, hypertension, hyperlipidemia and smoking. Infrarenal aortic diameter and aortoiliac bifurcation level were compared between the three groups. RESULTS: Pairwise comparisons between the three groups of patients with Pfirrmann grades of I-II, III and IV-V revealed significant differences (p < 0.05) in terms of the median infrarenal aortic diameter (17 mm [interquartile range 4], 18 mm [4] and 19 mm [4], respectively) and the median aortoiliac bifurcation level (3 [2], 4 [2] and 5 [3], respectively; the higher the value, the more the caudal displacement). These associations were independent of conventional risk factors of atherosclerosis (including age) and from each other. CONCLUSIONS: This study showed a significant, direct correlation of the infrarenal aortic diameter and the level of aortoiliac bifurcation with lumbar intervertebral degenerative changes according to the Pfirrmann grading system. The associations were independent of well-known risk factors of atherosclerosis and from each other.

The inability of an early post-transplantation intrarenal resistive index to predict renal allograft function at 12 weeks after engraftment in young adults.

Background The intrarenal resistive index (RI) is a promising tool for predicting renal graft outcomes. Due to the complexity of graft function and the presence of diverse contributing factors, however, the available data are inconclusive. Purpose To examine the performance of the RI 1 week after transplant in predicting allograft function at week 12, with an emphasis on the type of intrarenal artery used in the examination. Material and Methods A total of 58 first-time living-donor kidney-allograft-transplantation patients aged less than 50 years underwent Doppler ultrasonography (US) of the intrarenal arteries 1 week after engraftment. The RI was calculated for both the segmental (RI-C) and interlobar-arcuate (RI-P) arteries. Serum creatinine level and the creatinine reduction ratio (CRR) were determined at weeks 1 and 12 post transplantation. Results While the RI did not correlate with serum creatinine level and CRR at week 1, significant correlations were present between the RI and serum creatinine level (r = 0.28, P = 0.03 for both RI-C and RI-P) and CRR (r = -0.25, P = 0.05 for both RI-C and RI-P) at week 12. The sensitivity, specificity, positive predictive value, and negative predictive value of using RI-C in predicting abnormal 12-week serum creatinine level were 51.2%, 52.9%, 72.4%, and 31.3%, respectively; and 53.7%, 47.1%, 70.9%, and 29.6% for RI-P, respectively ( P > 0.99 for all comparisons). Conclusion Early post-transplantation RI correlates significantly with both serum creatinine level and creatinine reduction ratio 12 weeks after engraftment with intermediate predictive accuracy.

Correlation between pelvic tilt and the sacro-femoral-pubic angle in patients with adolescent idiopathic scoliosis, patients with congenital scoliosis, and healthy individuals.

PURPOSE: To examine whether the sacro-femoral-pubic (SFP) angle could estimate pelvic tilt (PT) in scoliotic and normal subjects. METHODS: One hundred nine subjects including 38 patients with adolescent idiopathic scoliosis (AIS), 35 patients with congenital scoliosis (CS), and 36 healthy individuals were studied. PT, as the angle between the lines connecting the midpoint of the sacral plate to the centroid of one acetabulum and the vertical plane, and the SFP angle, as the angle between the midpoint of the upper sacral endplate, the centroid of one acetabulum, and the upper midpoint of the pubic symphysis, were calculated on full-length lateral and anteroposterior radiographs, respectively. Correlations between PT and the SFP angle were investigated in each group. RESULTS: The three groups were comparable in terms of age, sex, and the mean SFP angle. The mean PT, however, was significantly lower in healthy subjects compared to that in patients with AIS and CS. Significant and reverse correlations were present between PT and the SFP angle in all three groups (AIS: r = -0.32, p = 0.04, PT = 82.5 - average SFP angle; CS: r = -0.48, p = 0.003, PT = 95.41 - average SFP angle; healthy: r = -0.33, p = 0.04, PT = 88.95 - average SFP angle). CONCLUSIONS: Unlike two previous reports, the SFP angle correlated poorly to PT in this study, limiting its use as a suitable surrogate for PT in scoliotic and healthy subjects.

Orientation of the facet joints in degenerative rotatory lumbar scoliosis: an MR study on 52 patients.

BACKGROUND: Because of a degenerative component, degenerative rotatory scoliosis seems different from congenital and idiopathic subtypes of the disease. This study aims to examine the orientation of facet joints, as a known cause of degeneration, in patients with degenerative rotatory scoliosis. METHODS: Lumbar magnetic resonance (MR) images and plain radiographs of 52 symptomatic patients (mean age, 50.17 years) with degenerative rotatory lumbar scoliosis (mean curve, 19.22 degrees) and 50 healthy individuals were reviewed. Facet joint angles in rotated segments and the minimum neural foramen width at all lumbar levels were measured by three observers and the average was recorded. RESULTS: The maximum vertebral rotation was most frequent at L4-L5 (75 %), and the majority was of type I (84.6 %) according to the Nash-Moe classification. At all lumbar spinal levels the mean facet joint angles were significantly higher on the side of rotation (L2-L3, 57.92 degrees; L3-L4, 45.00 degrees; L4-L5, 43.88 degrees) compared to those on the contralateral side (L2-L3, 20.42 degrees; L3-L4, 15.48 degrees; L4-L5, 13.12 degrees) and in controls (L2-L3, 30.21 degrees; L3-L4, 40.81 degrees; L4-L5, 45.20 degrees) (p < 0.001 for all comparisons). The mean facet joint angle increased significantly from L4-L5 to L2-L3 in cases and reversely in controls. The mean minimum neural foramen width was 1.29 ± 0.85 mm on the side of rotation, 5.50 ± 1.09 mm on the contralateral side, and 6.78 ± 1.75 mm in controls (p < 0.001). CONCLUSIONS: Substantial asymmetries and abnormal orientations in facet joints were documented in patients with degenerative rotatory lumbar scoliosis. Such asymmetries may adversely affect neural foramen width.

Redundant nerve roots of the cauda equina in lumbar spinal canal stenosis, an MR study on 500 cases.

PURPOSE: The purpose of this study was to evaluate magnetic resonance (MR)-detected redundant nerve roots (RNRs) of the cauda equina in patients with lumbar spinal canal stenosis. METHODS: A total of 500 lumbar MR studies in patients with lumbar spinal canal stenosis were reviewed for the presence and characteristics of RNRs of the cauda equina. The length of the RNRs relative to the height of the upper vertebral body of the level of the stenosis was used as a prognostic indicator. RESULTS: RNRs were detected in 15% of the patients, the majority above the level of the stenosis (85%) and loop shaped (72%). Advanced age (i.e., ≥56 years old, odds ratio=1), a lumbar spinal canal stenosis at L2-4 (odds ratio=2.5), and the presence of an intracanal protuberance with sharp margin in the site of the stenosis (odds ratio=7.2) were independent risk factors for the development of RNRs. A direct, significant correlation was found between the relative length of the RNRs and patients' age (Pearson r=0.36, p=0.001). The mean relative length of the RNRs was significantly higher in patients with RNRs located above the level of the stenosis than those with RNRs located below the site of the block. The degree of stenosis was associated with neither the presence nor the relative length of the RNRs. CONCLUSIONS: With an occurrence rate of 15%, RNRs of the cauda equina are not uncommon in cases with lumbar spinal canal stenosis. Advanced age, a canal stenosis at L2-4, and the presence of a sharp intracanal protuberance in the site of the stenosis are the related risk factors. Patients' age and the location of RNRs may be of prognostic value.

Vertebral, rib, and intraspinal anomalies in congenital scoliosis: a study on 202 Caucasians.

PURPOSE: To investigate vertebral, rib and intraspinal anomalies in patients with congenital scoliosis and their association with each other METHODS: Clinical data and preoperative imaging studies of 202 Caucasians with congenital scoliosis operated on at an educational hospital within 6 years were reviewed for vertebral, rib, and intraspinal anomalies. RESULTS: Rib and intraspinal anomalies were present in 57.4 and 21.8 % of patients, respectively. Most vertebral anomalies were located in the middle-lower thorax. Being the most common vertebral defect (53.5 %), failure of segmentation was significantly more common in males, whereas mixed defects were more frequent in females. Formation and mixed defects were associated with rib changes. Vertebral anomalies were more extensive in males than in females. The presence of multiple hemivertebrae was associated with rib deformity and intraspinal anomaly. Location of the vertebral anomalies varied with gender and rib involvement. Majority of rib changes were of simple type (70.7 %), significantly more common in males. Conversely, females had significantly more fused and bifid ribs. Two most common intraspinal anomalies were diastematomyelia (36.4 %) and syringomyelia (18.2 %). Intraspinal anomalies were located most frequently in the upper and lower thoracic regions. Syringomyelia and low conus were associated with female gender, and patients with rib changes suffered from intraspinal anomalies more frequently. No significant association was found between vertebral and intraspinal anomalies. CONCLUSIONS: The incidences of rib and intraspinal anomalies were 57.4 and 21.8 % in surgical Caucasians with congenital scoliosis, respectively. Unlike vertebral and intraspinal anomalies, rib and intraspinal anomalies were significantly associated. Male gender and intraspinal anomaly were associated with some previously suggested risk factors of curve progression.

The utility of ultrasonographic bone age determination in detecting growth disturbances; a comparative study with the conventional radiographic technique.

OBJECTIVE: To test whether the conventional radiographic technique in determining bone age abnormalities can be replaced by ultrasonography. MATERIALS AND METHODS: A total of 54 Caucasian subjects up to 7 years of age with clinically suspected growth problems underwent left hand and wrist radiographic and ultrasonographic bone age estimations with the use of the Greulich-Pyle atlas. The ultrasonographic scans targeted the ossification centers in the radius and ulna distal epiphysis, carpal bones, epiphyses of the first and third metacarpals, and epiphysis of the middle phalanx, as described in previous reports. The degree of agreement between the two sets of data, as well as the accuracy of the ultrasonographic method in detecting radiographically suggested bone age abnormities, was examined. RESULTS: The mean chronological age, radiographic bone age, and ultrasonographic bone age (all in months) were 41.96 ± 22.25, 26.68 ± 14.08, and 26.71 ± 13.50 in 28 boys and 43.62 ± 24.63, 30.12 ± 17.69, and 31.27 ± 18.06 in 26 girls, respectively. According to the Bland-Altman plot there was high agreement between the results of the two methods with only three outliers. The deviations in bone age from the chronological age taken by the two techniques had the same sign in all patients. Supposing radiography to be the method of reference, the sensitivity, specificity, positive predictive value, and negative predictive value of sonography in detecting growth abnormalities were all 100% in males and 90.9, 100, 100, and 93.8%, respectively, in females. CONCLUSION: The conventional radiographic technique for determining bone age abnormalities could be replaced by ultrasonography.

Vascular Doppler ultrasonographic indices in cirrhosis: a case-control study with emphasis on the common carotid arteries.

PURPOSE: To compare vascular Doppler waveform indices, particularly in the common carotid arteries, between cirrhotic and healthy subjects. MATERIALS AND METHODS: A total of 60 patients with Class-B cirrhosis and 60 healthy matched counterparts were enrolled in this prospective study. Vascular Doppler waveform parameters including resistance and/or pulsatility indices (RI and PI, respectively) were obtained from the common carotid, renal, celiac, superior mesenteric, femoral and brachial arteries. RESULTS: Compared to patients, healthy subjects had significantly higher mean PI and RI obtained from the common carotid (1.53 ± 0.20 vs. 1.43 ± 0.14, p = 0.03; 0.75 ± 0.02 vs. 0.72 ± 0.02, p < 0.001, respectively) and celiac arteries (2.00 ± 0.36 vs. 1.81 ± 0.34, p = 0.03; 0.80 ± 0.03 vs. 0.78 ± 0.02, p < 0.001, respectively). Both the mean PI and RI derived from the renal arteries, in contrast, were significantly higher in patients compared to that in controls (1.05 ± 0.13 vs. 1.11 ± 0.07, p = 0.03; 0.59 ± 0.03 vs. 0.63 ± 0.03, p < 0.001, respectively). The mean vascular impedance values obtained from the remaining arteries were comparable between the two groups. CONCLUSIONS: Blood flow increases in the common carotid and celiac arteries of Class-B cirrhotic patients with elevated renovascular impedance.

Deep neural network-based segmentation of normal and abnormal pancreas on abdominal CT: evaluation of global and local accuracies.

PURPOSE: Delay in diagnosis can contribute to poor outcomes in pancreatic ductal adenocarcinoma (PDAC), and new tools for early detection are required. Recent application of artificial intelligence to cancer imaging has demonstrated great potential in detecting subtle early lesions. The aim of the study was to evaluate global and local accuracies of deep neural network (DNN) segmentation of normal and abnormal pancreas with pancreatic mass. METHODS: Our previously developed and reported residual deep supervision network for segmentation of PDAC was applied to segment pancreas using CT images of potential renal donors (normal pancreas) and patients with suspected PDAC (abnormal pancreas). Accuracy of DNN pancreas segmentation was assessed using DICE simulation coefficient (DSC), average symmetric surface distance (ASSD), and Hausdorff distance 95% percentile (HD95) as compared to manual segmentation. Furthermore, two radiologists semi-quantitatively assessed local accuracies and estimated volume of correctly segmented pancreas. RESULTS: Forty-two normal and 49 abnormal CTs were assessed. Average DSC was 87.4 ± 3.1% and 85.5 ± 3.2%, ASSD 0.97 ± 0.30 and 1.34 ± 0.65, HD95 4.28 ± 2.36 and 6.31 ± 6.31 for normal and abnormal pancreas, respectively. Semi-quantitatively, ≥95% of pancreas volume was correctly segmented in 95.2% and 53.1% of normal and abnormal pancreas by both radiologists, and 97.6% and 75.5% by at least one radiologist. Most common segmentation errors were made on pancreatic and duodenal borders in both groups, and related to pancreatic tumor including duct dilatation, atrophy, tumor infiltration and collateral vessels. CONCLUSION: Pancreas DNN segmentation is accurate in a majority of cases, however, minor manual editing may be necessary; particularly in abnormal pancreas.

Hepatic angiosarcoma in an adult who had Wilms tumor treated in childhood: A case report.

Hepatic angiosarcoma is a rare, highly aggressive mesenchymal liver malignancy with poor prognosis that stems from the endothelial cells that line the walls of blood or lymphatic vessels. It is the third most common primary liver malignancy and is most prevalent among older males. It is difficult to diagnose due to various clinical presentations from asymptomatic to abdominal pain, pleural effusion, and liver failure. The diagnosis of liver angiosarcoma is suspected on imaging features and confirmed by histopathological assessment. Primary management is determined based on the stage of tumor from surgery to palliative care such as chemotherapy or tumor transarterial embolization. We report a 51-year-old female who presented with stage 4 liver angiosarcoma and a history of childhood Wilms tumor. We focus on tumor management using radiological modalities and pathological analysis and discuss secondary liver tumors in survivors of childhood Wilms tumor.

Intra-abdominal lymphangioma: A case report.

Lymphangioma is a rare, benign congenital malformation of the lymphatic system that usually affects the neck and head in children. Intra-abdominal lymphangioma accounts for less than 5 percent of all cases of lymphangioma. The clinical presentation of intra-abdominal lymphangioma can vary from asymptomatic to nausea, vomiting, and abdominal pain. The diagnosis of intra-abdominal lymphangioma is based on imaging modalities and histopathological examination. The definitive treatment is surgical resection. Here we describe the interesting and rare case of a 29-year-old woman with lymphangioma of the retroperitoneum extending to the root of the mesentery. We focus on the diagnosis and management of this rare tumor by the application of radiological modalities and pathological analysis.

Accuracy of ultrasonography in detecting gastrointestinal tract obstructions in children; a prospective study in a tertiary referral hospital.

AIMS: To examine the diagnostic accuracy of plain radiography, abdominal ultrasonography (US), and their combination in pediatric patients with suspected gastrointestinal (GI) tract obstruction. MATERIAL AND METHODS: A cohort of 48 patients (age, 0-14 years, 27 boys) with clinical manifestations of GI tract obstruction underwent plain radiography and abdominal US examination. The final diagnoses were based on intraoperative findings, rectal biopsies (in Hirschsprung's disease), or adequate follow-ups. RESULTS: The GI tract obstruction was diagnosed in 40 patients. The sensitivity, specificity, positive predictive value and negative predictive value of plain radiography in diagnosing GI tract obstruction were 87.5%, 75.0%, 94.6%, and 54.6%, respectively. The corresponding values were 95%, 100%, 100%, and 80%, respectively when US was used alone; and 97.5%, 100%, 100% and 88.9%, respectively when radiography and US were used together. Except for two patients (one with Hirschsprung's disease and the other with massive peritonitis), US detected the underlying causes of obstruction correctly in all patients. CONCLUSIONS: US is a highly sensitive and specific modality in diagnosing pediatric GI tract obstructions, as well as their causes. The combination of plain radiography and US further increase the diagnostic sensitivity and negative predictive value.

Ectopic Cushing syndrome caused by a pancreatic neuroendocrine tumor: A case report.

Cushing syndrome is a disorder that occurs when the body is exposed to a higher than normal level of the hormone cortisol. It is most commonly caused by exogenous glucocorticoids, and less commonly due to endogenous sources. Ectopic adrenocorticotropic hormone (ACTH) syndrome is one of the rare causes of endogenous Cushing syndrome engendered by oversecretion of ACTH from a tumor outside of the pituitary or adrenal glands. We present a case of a 74-year-old male with uncontrolled type 2 diabetes mellitus who was suspected of having Cushing syndrome on chest CT due to increasing mediastinal lipomatosis and enlarging bilateral adrenal glands. Cushing syndrome was confirmed based on clinical features and biochemical tests. Further investigation revealed an ACTH-producing functional neuroendocrine tumor of the pancreas causing ectopic Cushing syndrome.