Contrast-enhanced Abdominal CT Research Articles

Spinal fistulas documented by contrast enhanced computed tomography during myelopathy workup: a lost opportunity.

Low-flow spinal arteriovenous fistulas (SAVFs) with intradural venous drainage typically manifest with a progressive venous hypertensive myelopathy (VHM) in older patients. VHM is difficult to identify. MRI is often nonspecific, and many cases are initially misdiagnosed, most often as transverse myelitis. The workup of myelopathic patients frequently includes thoracic and/or abdominal contrast-enhanced CT (CECT) that are generally not reviewed by neuroradiologists. The purpose of this work was to investigate how often abnormal enhancing intracanalar structures corresponding to the draining veins of a low-flow SAVF were documented by CECT. We evaluated 92 consecutive patients with low-flow SAVFs and VHM treated at our institution between 2009 and 2018. The study group included 22 of these patients with at least one thoracoabdominal CECT available for review. The control group consisted of 20 consecutive myelopathy patients with negative angiography and at least one thoracoabdominal CECT. Intracanalar enhancing structures were classified either as (i) conspicuous or (ii) equivocal or absent. One CECT in the study group was technically inadequate. Conspicuous intracanalar enhancing structures were observed in 20 of the remaining 21 patients with SAVFs (95.2%) and in 2 of 20 control patients (10%). None of the enhancing intracanalar structures was mentioned in official study reports. The presence of enhancing vascular structures within the spinal canal on thoracoabdominal CECT obtained during the workup of myelopathies appears to represent a powerful but currently underappreciated tool for the detection of low-flow SAVFs.

Clinical implications of perivascular fat stranding surrounding spontaneous isolated superior mesenteric artery dissection on computed tomography.

Patients with spontaneous isolated superior mesenteric artery (SMA) dissection (SISMAD) usually present with acute or chronic abdominal pain and are admitted to the emergency or digestive diseases department to undergo auxiliary examinations, typically abdominal plain CT or contrast-enhanced CT (CECT). Plain CT is the most crucial examination in emergency radiology. An enlarged SMA diameter and perivascular fat stranding (PFS) on plain CT, though non-specific, may be the only indications for SISMAD. These results may be easily overlooked and the diagnosis of SISMAD may be missed. However, PFS around the SMA on CT may be the only indicator of the possible presence of SISMAD, particularly during the early stage when there are no massive changes in the vascular wall. The present study aimed to determine whether PFS surrounding the SMA on CT may help with the diagnosis of SISMAD by indicating the requirement for further examination. The data of 161 consecutive patients with SMA dissection who underwent abdominal CECT or underwent SMA CT angiography (CTA) after abdominal plain CT between February 2015 and February 2018 were retrospectively reviewed. SMA diameter, classification, PFS, complications, comorbidities and treatments were analyzed. The results demonstrated that SISMAD with PFS was significantly associated with admission type (emergency), clinical manifestations (abdominal pain), diagnostic modality and dissection subtype. On plain CT, PFS surrounding the SMA may be a marker for SISMAD, particularly in the emergency setting, and indicates the requirement for CTA examination.

Decreasing the radiation dose for contrast-enhanced abdominal spectral CT with a half contrast dose: a matched-pair comparison with a 120 kVp protocol.

Objectives:To compare the estimated radiation dose of 50% reduced iodine contrast medium (halfCM) for virtual monochromatic images (VMIs) with that of standard CM (stdCM) with a 120 kVp imaging protocol for contrast-enhanced CT (CECT).Methods:We enrolled 30 adults with renal dysfunction who underwent abdominal CT with halfCM for spectral CT. As controls, 30 matched patients without renal dysfunction using stdCM were also enrolled. CT images were reconstructed with the VMIs at 55 keV with halfCM and 120 kVp images with stdCM and halfCM. The Monte-Carlo simulation tool was used to simulate the radiation dose. The organ doses were normalized to CTDIvol for the liver, pancreas, spleen, and kidneys and measured between halfCM and stdCM protocols.Results:For the arterial phase, the mean organ doses normalized to CTDIvol for stdCM and halfCM were 1.22 and 1.29 for the liver, 1.50 and 1.35 for the spleen, 1.75 and 1.51 for the pancreas, and 1.89 and 1.53 for the kidneys. As compared with non-enhanced CT, the average increase in the organ dose was significantly lower for halfCM (13.8% ± 14.3 and 26.7% ± 16.7) than for stdCM (31.0% ± 14.3 and 38.5% ± 14.8) during the hepatic arterial and portal venous phases (p < 0.01).Conclusion:As compared with stdCM with the 120 kVp imaging protocol, a 50% reduction in CM with VMIs with the 55 keV protocol allowed for a substantial reduction of the average organ dose of iodine CM while maintaining the iodine CT number for CECT.Advances in knowledge:This study provides that the halfCM protocol for abdominal CT with a dual-layer-dual-energy CT can significantly reduce the increase in the average organ dose for non-enhanced CT as compared with the standard CM protocol.

Multivariate analysis of CT imaging, laboratory, and demographical features for prediction of acute kidney injury in COVID-19 patients: a Bi-centric analysis.

PurposeTo develop and externally validate a multivariate prediction model for the prediction of acute kidney injury (AKI) in COVID-19, based on baseline renal perfusion from contrast-enhanced CT together with clinical and laboratory parameters.MethodsIn this retrospective IRB-approved study, we identified COVID-19 patients who had a standard-of-care contrast-enhanced abdominal CT scan within 5 days of their COVID-19 diagnosis at our institution (training set; n = 45, mean age 65 years, M/F 23/22) and at a second institution (validation set; n = 41, mean age 61 years, M/F 22/19). The CT renal perfusion parameter, cortex-to-aorta enhancement index (CAEI), was measured in both sets. A multivariate logistic regression model for predicting AKI was constructed from the training set with stepwise feature selection with CAEI together with demographical and baseline laboratory/clinical data used as input variables. Model performance in the training and validation set was evaluated with ROC analysis.ResultsAKI developed in 16 patients (35.6%) of the training set and in 6 patients (14.6%) of the validation set. Baseline CAEI was significantly lower in the patients that ultimately developed AKI (P = 0.003). Logistic regression identified a model combining baseline CAEI, blood urea nitrogen, and gender as most significant predictor of AKI. This model showed excellent diagnostic performance for prediction of AKI in the training set (AUC = 0.89, P < 0.001) and good performance in the validation set (AUC 0.78, P = 0.030).ConclusionOur results show diminished renal perfusion preceding AKI and a promising role of CAEI, combined with laboratory and demographic markers, for prediction of AKI in COVID-19.

Synchronous hepatocellular carcinoma and gallbladder adenocarcinoma with neuroendocrine differentiation: a case report and literature review

BackgroundDouble primary cancers have a low incidence rate, and synchronous hepatocellular carcinoma and gallbladder adenocarcinoma are rarely reported. Here, we report such a case— the 12th case of synchronous double primary cancers featuring HCC and GC, but the first case of neuroendocrine differentiation in the gallbladder.Case presentationA 77-year-old female was admitted to the hospital complaining of weakness and inappetence for six months. Contrast-enhanced computed tomography (CT) of the abdomen indicated an 11 cm space-occupying lesion in the right lobe of the liver. Later, magnetic resonance imaging showed a high possibility of a massive hepatoma, and multiple gallstones were also seen. After transhepatic arterial chemoembolization, a repeat abdominal CT showed obvious local nodular thickening in the gallbladder wall. Finally, resection of the right lobe of the liver and cholecystectomy were performed. During an approximately 2-year follow-up, the patient recovered uneventfully without recurrence or metastasis.ConclusionThe disease in this case is rare and lacked typical radiological features. More precise and advanced diagnostic techniques are needed to obtain a clear diagnosis and refine treatment strategies. The management strategy should always be curative, even in the presence of multiple malignancies.

Improving the slice interaction of 2.5D CNN for automatic pancreas segmentation.

Volumetric pancreas segmentation can be used in the diagnosis of pancreatic diseases, the research about diabetes and surgical planning. Since manual delineation is time-consuming and laborious, we develop a deep learning-based framework for automatic pancreas segmentation in three dimensional (3D) medical images. A two-stage framework is designed for automatic pancreas delineation. In the localization stage, a Square Root Dice loss is developed to handle the trade-off between sensitivity and specificity. In refinement stage, a novel 2.5D slice interaction network with slice correlation module is proposed to capture the non-local cross-slice information at multiple feature levels. Also a self-supervised learning-based pre-training method, slice shuffle, is designed to encourage the inter-slice communication. To further improve the accuracy and robustness, ensemble learning and a recurrent refinement process are adopted in the segmentation flow. The segmentation technique is validated in a public dataset (NIH Pancreas-CT) with 82 abdominal contrast-enhanced 3D CT scans. Fourfold cross-validation is performed to assess the capability and robustness of our method. The dice similarity coefficient, sensitivity, and specificity of our results are 86.21±4.37%, 87.49±6.38% and 85.11±6.49% respectively, which is the state-of-the-art performance in this dataset. We proposed an automatic pancreas segmentation framework and validate in an open dataset. It is found that 2.5D network benefits from multi-level slice interaction and suitable self-supervised learning method for pre-training can boost the performance of neural network. This technique could provide new image findings for the routine diagnosis of pancreatic disease.

Splenic abscess caused by Streptococcus anginosus bacteremia secondary to urinary tract infection: a case report and literature review

Organ abscesses caused by Streptococcus anginosus are relatively rare. We report the case of an elderly woman with splenic abscess caused by S. anginosus bacteremia after urinary tract infection. An 82-year-old woman had a history of frequency of urination, urgency, and fever with chills for over 10 days prior to admission. An abdominal computed tomography (CT) scan performed in the emergency room revealed a low-density lesion in the spleen, kidney cysts, some exudation around the kidney, and cystitis should be valued. She was treated with ceftriaxone and imipenem/cilastatin. After admission, the blood culture yielded positive results for S. anginosus. A contrast-enhanced abdominal CT scan showed that the low-density lesion previously found in the spleen was smaller than before. After percutaneous drainage of the splenic abscess and treatment with piperacillin/tazobactam based on the antibiotic sensitivity pattern, repeated abdominal CT scan revealed a significant reduction in the low-density lesion. The patient was discharged without recurrence or complications. A systematic review of organ abscess caused by S. anginosus bacteremia was performed. To our knowledge, there has been no report of splenic abscess caused by S. anginosus bacteremia secondary to urinary system tract infection, although urinary tract infections are also an important source.

MANAGEMENT OF PNEUMATOSIS INTESTINALIS IN LUNG TRANSPLANT RECIPIENTS: A SINGLE-CENTER EXPERIENCE

SESSION TITLE: Transplantation Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: October 18-21, 2020 PURPOSE: Pneumatosis intestinalis (PI) is an uncommon, and often times incidental, clinical finding characterized by submucosal or subserosal gas-filled cysts within the bowel wall. PI may be encountered in a wide array of clinical settings, but it is scarcely reported after lung transplantation (LTx). METHODS: We constructed a retrospective review of LTx recipients with post-transplant, benign PI at our institution in 2019. RESULTS: Four LTx recipients developed post-transplant, benign PI at our institution during the study period. Two cases of benign PI were discovered incidentally on routine surveillance chest radiographs during clinic visits. Both patients had uneventful post-transplant recovery and were asymptomatic at presentation. A third case with otherwise uneventful post-transplant course presented to the emergency department with mild symptoms of vague abdominal discomfort, with chest radiograph revealing PI. A fourth case who underwent bilateral LTx with left atrial appendage clipping from cardiopulmonary bypass had a complicated post-transplant course, requiring tracheostomy and a gastric feeding tube; PI was identified in the ascending colon on ischemic stroke workup. All four patients were admitted for further observation, and contrast-enhanced abdominal CT scans confirmed the initial imaging findings. Clinical signs and imaging features in these situations may mimic true bowel perforation, so colorectal surgery was routinely consulted for discussion of appropriate management. A conservative approach consisting of bowel rest, intravenous hydration, nasogastric decompression, and gastric tube feedings was chosen for all four cases. All patients received empiric antibiotic treatment with Zosyn for bacterial decontamination. Antibiotic treatment and nasogastric decompression relieved symptoms, and surgical intervention remained unnecessary. Food was slowly reintroduced, as tolerated, when serial kidney, ureter, and bladder scans improved. There were no complications from PI. All patients were safely discharged when deemed stable after unremarkable abdominal scans. CONCLUSIONS: PI is a rare post-transplant condition that may be identified incidentally in an asymptomatic patient. Greater awareness of this entity, especially amongst transplant clinicians, may improve management of these patients. CLINICAL IMPLICATIONS: Herein, we detail the appropriate management in four patients with a post-transplant condition rarely reported after LTx. DISCLOSURES: No relevant relationships by ASHWINI ARJUNA, source=Web Response no disclosure on file for Bhuvin Buddhev; No relevant relationships by Hesham Mohamed, source=Web Response No relevant relationships by Michael Olson, source=Web Response Speaker/Speaker's Bureau relationship with Genentech Please note: $5001 - $20000 by Rajat Walia, source=Admin input, value=Honoraria Speaker/Speaker's Bureau relationship with Boehringer Ingelheim Please note: $5001 - $20000 by Rajat Walia, source=Admin input, value=Honoraria Speaker/Speaker's Bureau relationship with Grifols Please note: $5001 - $20000 by Rajat Walia, source=Admin input, value=Honoraria Speaker/Speaker's Bureau relationship with Shire Please note: $1001 - $5000 by Rajat Walia, source=Admin input, value=Honoraria Speaker/Speaker's Bureau relationship with Astellas Please note: $5001 - $20000 by Rajat Walia, source=Admin input, value=Honoraria

Fully automated CT imaging biomarkers of bone, muscle, and fat: correcting for the effect of intravenous contrast.

Fully automated CT-based algorithms for quantifying bone, muscle, and fat have been validated for unenhanced abdominal scans. The purpose of this study was to determine and correct for the effect of intravenous (IV) contrast on these automated body composition measures. Initial study cohort consisted of 1211 healthy adults (mean age, 45.2years; 733 women) undergoing abdominal CT for potential renal donation. Multiphasic CT protocol consisted of pre-contrast, arterial, and parenchymal phases. Fully automated CT-based algorithms for quantifying bone mineral density (BMD, L1 trabecular HU), muscle area and density (L3-level MA and M-HU), and fat (visceral/subcutaneous (V/S) fat ratio) were applied to pre-contrast and parenchymal phases. Effect of IV contrast upon these body composition measures was analyzed. Square of the Pearson correlation coefficient (r2) was generated for each comparison. Mean changes (± SD) in L1 BMD, L3-level MA and M-HU, and V/S fat ratio were 26.7 ± 27.2 HU, 2.9 ± 10.2 cm2, 18.8 ± 6.0 HU, - 0.1 ± 0.2, respectively. Good linear correlation between pre- and post-contrast values was observed for all automated measures: BMD (pre = 0.87 × post; r2 = 0.72), MA (pre = 0.98 × post; r2 = 0.92), M-HU (pre = 0.75 × post + 5.7; r2 = 0.75), and V/S (pre = 1.11 × post; r2 = 0.94); p < 0.001 for all r2 values. There were no significant trends according to patient age or gender that required further correction. Fully automated quantitative tissue measures of bone, muscle, and fat at contrast-enhanced abdominal CT can be correlated with non-contrast equivalents using simple, linear relationships. These findings will facilitate evaluation of mixed CT cohorts involving larger patient populations and could greatly expand the potential for opportunistic screening.

Cascaded U-net for Kidney and Tumor Segmentation from CT volumes

Contrast-enhanced Computed Tomography (CT) imaging is most useful tool in diagnosing and locating the kidney lesions. An automated kidney and tumor segmentation are very helpful because it can provide the precise information about the location and size of lesions which can be used in quantitative analysis of the tumor. Semantic segmentation of kidney is very challenging as it requires large dataset for training and its morphological heterogeneity makes it a difficult problem. The 2019 Kidney and Kidney Tumor Segmentation challenge (KiTS19) was a competition held in conjunction with the 2019 International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI) has publicly released a 210 cross sectional CT images with kidney tumors along with corresponding semantic segmentation masks. In this work we proposed a novel two stage 2D segmentation method to automatically segment kidney and tumor using the combination of Unet++ and squeeze and excite approach. The proposed network is trained in keras framework. Our method achieves a dice score of 0.98 and 0.965 with kidney and tumor respectively on training data and the results demonstrates the accuracy of our proposed method. Proposed method was able to segment kidney and tumor from abdominal CT images which can provide the exact location and size of the tumor. This information can also be used to analyze treatment response.

Features of extrahepatic metastasis after radiofrequency ablation for hepatocellular carcinoma.

BACKGROUNDExtrahepatic metastasis (EHM) of hepatocellular carcinoma (HCC) is associated with poor outcomes. However, the clinical features and risk factors of EHM of HCC after radiofrequency ablation (RFA) remain unclear.AIMTo elucidate the characteristics and risk factors of EHM after RFA for HCC.METHODSFrom January 2008 to December 2017, we retrospectively enrolled 661 patients who underwent RFA as first-line treatment for HCC at 2 tertiary hospitals. The inclusion criteria were age ≥ 18 years, a diagnosis of HCC, and treatment-naivety. Abdominal computed tomography (CT) or magnetic resonance imaging (MRI) and alpha-fetoprotein measurements were routinely performed at 1 mo after RFA and followed-up at intervals of 3-6 mo. Univariate analyses were performed using the chi-squared test or Student’s t-test, and univariate and multivariate analyses were performed via logistic regression, as appropriate.RESULTSEHM was diagnosed in 44 patients (6.7%) during a median follow-up period of 1204 days. The 10-year cumulative rate of HCC recurrence and EHM was 92.7% and 33.7%, respectively. Initial recurrence was most often intrahepatic, and the rate of extrahepatic recurrence at initial recurrence was only 1.2%. The median time to the diagnosis of EHM was 2.68 years, and 68.2% of patients developed EHM within 2 years of the first recurrence, regardless of recurrence-free survival and 75.0% of patients developed EHM within 5 years after first recurrence. EHM was mostly diagnosed via abdominal CT/MRI in 33 (75.0%) and 38 of 44 patients (86.4%) with EHM had either positive abdominal CT scan results or serum AFP level elevation. In multivariate analysis, recurrence-free survival < 2 years, ablation zone/tumor size < 2, and alpha-fetoprotein level > 400 IU/mL were associated with a high EHM risk.CONCLUSIONEHM occurs following multiple intrahepatic recurrences after RFA and combined contrast-enhanced abdominal CT and serum AFP were useful for surveillance. Patients especially with high-risk factors require close follow-up for EHM.

Texture Analysis as a Radiomic Marker for Differentiating Benign From Malignant Adrenal Tumors.

The aim of this study was to evaluate the use of texture analysis for differentiation between benign from malignant adrenal lesions on contrast-enhanced abdominal computed tomography (CT). After institutional review board approval, a retrospective analysis was performed, including an electronic search of pathology records for all biopsied adrenal lesions. Patients were included if they also had a contrast-enhanced abdominal CT in the portal venous phase. Computed tomographic images were manually segmented, and texture analysis of the segmented tumors was performed. Texture analysis results of benign and malignant tumors were compared, and areas under the curve (AUCs) were calculated. One hundred twenty-five patients were included in the analysis. Excellent discriminators of benign from malignant lesions were identified, including entropy and standard deviation. These texture features demonstrated lower values for benign lesions compared with malignant lesions. Entropy values of benign lesions averaged 3.95 using a spatial scaling factor of 4 compared with an average of 5.08 for malignant lesions (P < .0001). Standard deviation values of benign lesions averaged 19.94 on the unfiltered image compared with an average of 34.32 for malignant lesions (P < .0001). Entropy demonstrated AUCs ranging from 0.95 to 0.97 for discriminating tumors, with sensitivities and specificities ranging from 81% to 95% and 88% to 100%, respectively. Standard deviation demonstrated AUCs ranging from 0.91 to 0.94 for discriminating tumors, with sensitivities and specificities ranging from 73% to 93% and 86% to 95%, respectively. Texture analysis offers a noninvasive tool for differentiating benign from malignant adrenal tumors on contrast-enhanced CT images. These results support the further development of texture analysis as a quantitative biomarker for characterizing adrenal tumors.

Feasibility of near-infrared fluorescence imaging in assisting with the determination of the resection range of radiation intestinal injury

Objective: To investigate the feasibility of near-infrared fluorescence imaging (NIRFI) to assist in determining the resection range of radiation intestinal injury (RII). Methods: A descriptive cohort study was conducted. Clinical data of 10 RII patients who presented intestinal obstruction and received operation with more than 100 cm of small intestine had been resected atGeneral Department of Jinling Hospital from October 2014 to January 2015 were retrospectively analyzed. The Novadaq SPY Intra-operative Imaging System was used in capturing and viewing fluorescent images. Firstly, the dense adhesion was mobilized and the obstructive intestine was fully freed under laparoscopy, then entering into abdomen from the corresponding incision. The surgeon determined the resection range according to the color of the intestinal serous layer of the diseased intestinal wall, the thickness of the intestinal wall, and the degree of swelling of the mesentery. Afterwards, intra-operative NIRFI was performed by intravenous injection of 2 ml indocyanine green (ICG) and the imaging results of the diseased intestinal arteriovenous phase were observed and recorded. The evaluation criteria for the final resection range were mainly based on the changes in mesenteric arterial phase imaging. In RII lesions, mesenteric vessels in mesenteric artery phase were disordered, and the comb-like distribution of normal mesenteric vessels completely disappeared. Only the clouded appearance in the intestinal wall was observed. Imaging results of the diseased intestinal tissue during the development phase and mesenteric vein phase were not significantly different from normal intestinal tissue. Intraoperative and postoperative conditions under NIRFI-assisted positioning, including the resection range, anastomosis site, operation-related complications, hospitalization time and cost were recorded. Data of abdominal contrast-enhanced CT and gastrointestinal angiography during 5 years of follow-up were collected to evaluate whether there was anastomotic stenosis or insufficient resection of diseased bowel. Results: Based on the imaging of mesenteric arterial phase of NIRFI, the median resection length of the small intestine was 185 (120-260) cm. After NIRFI imaging, only local lesion of ileum was excised in 6 patients, and jejunum-ileum anastomosis was performed to preserve ileocecal flap. No serious complications such as anastomotic leakage and anastomotic hemorrhage, or chronic intestinal failure such as short bowel syndrome occurred. The median hospitalization time was 32 (22-51) days, and the median hospitalization cost was 142 000 (90 000-175 000) RMB. The hospitalization time and cost were mainly used for the enteral and parenteral nutrition support treatment during the perioperative period. All the patients had normal oral diet and/or oral enteral nutrient. After 5 years of follow-up, no recurrence was found. Abdominal contrast-enhanced CT and gastrointestinal angiography showed no thickening of the intestinal wall or stenosis of the lumen. Conclusion: Mesenteric arterial phase imagingof NIRFI can help surgeons to determine the site and range of resection of RII lesions.

Evaluation of intrahepatic manifestation and distant extrahepatic disease in alveolar echinococcosis.

BACKGROUNDThe main endemic areas of alveolar echinococcosis (AE) are in Central Europe and Western China. Both the infiltration of intrahepatic vascular and bile duct structures as well as extrahepatic disease can lead to further complications and may increase morbidity in patients with AE.AIMTo evaluate vascular/biliary involvement in hepatic AE and its distant extrahepatic disease manifestations in an international collective was the aim.METHODSConsecutively, five experienced examiners evaluated contrast-enhanced abdominal computed tomography (CT) scans for 200 patients with hepatic AE of each of four locations (n = 50) in Germany, France and China. Therefore, we retrospectively included the 50 most recent abdominal contrast-enhanced CT examinations at each center, performed because of hepatic AE from September 21, 2007 to March 21, 2018. AE liver lesions were classified according to the echinococcosis multilocularis Ulm classification for CT (EMUC-CT). Distant extrahepatic manifestations were documented either by whole body positron emission tomography–CT or with the addition of thoracic CT and cranial magnetic resonance imaging. Vascular/biliary involvement of the hepatic disease as well as the presence of distant extrahepatic manifestations were correlated with the EMUC-CT types of liver lesion. Statistical analysis was performed using SAS Version 9.4 (SAS Institute Inc., Cary, NC, United States).RESULTSDistant extrahepatic AE manifestations were significantly more frequent in China than in Europe (P = 0.0091). A significant relationship was found between the presence of distant extrahepatic disease and AE liver lesion size (P = 0.0075). Vascular/biliary structures were involved by the liver lesions significantly more frequently in China than in Europe (P < 0.0001), and vascular/biliary involvement depended on lesion size. Different morphological types of AE liver lesions led to varying frequencies of vascular/biliary involvement and were associated with different frequencies of distant extrahepatic manifestations: Vascular/biliary involvement as a function of lesions primary morphology ranged from 5.88% of type IV liver lesions to 100% among type III lesions. Type IV differed significantly in these associations from types I, II, and III (P < 0.0001). With respect to extrahepatic disease, the primary morphology types IV and V of liver lesions were not associated with any case of distant extrahepatic disease. In contrast, distant extrahepatic manifestations in types I–III were found to varying degrees, with a maximum of 22% for type III.CONCLUSIONDifferent CT morphological patterns of hepatic AE lesions influence vascular/biliary involvement and the occurrence of distant extrahepatic manifestations. There are intercontinental differences regarding the characteristics of AE manifestation.

Diagnosis of oligometastasis.

Metastatic breast cancer (MBC) is generally considered incurable. However, MBC which has limited number and sites of metastasis: oligometastatic breast cancer (OMBC) may have definitive remission with individualized, metastasis-directed ablative therapies and multidisciplinary management, such as surgery and radiotherapy. Earlier detection of primary metastatic breast cancer using accurate imaging technologies may allow the initiation of therapy for OMBC. In breast cancer, the lymph nodes, liver, bone, lung, and brain are common sites of metastasis. Additional studies are recommended if signs or symptoms indicate metastasis. The imaging modality should be selected for suspicious locations or original metastatic regions. The standard staging studies are ultrasonography for lymph node metastasis, abdominal and/or pelvic contrast-enhanced CT for liver metastasis, chest CT for pulmonary metastasis, and bone scan for bone metastasis. FDG-PET/CT may be helpful for bone or liver metastasis. MRI may be considered for liver, soft tissue, or brain metastasis.

Multisystem Assessment of the Imaging Manifestations of Coagulopathy in Hospitalized Patients With Coronavirus Disease (COVID-19).

BACKGROUND. Coronavirus disease (COVID-19) is known to be associated with a distinct form of coagulopathy. OBJECTIVE. The purpose of this study was to describe the imaging manifestations of COVID-19-associated coagulopathy across anatomic sites and modalities in hospitalized patients and to identify clinical variables associated with positive imaging findings. METHODS. We conducted a retrospective review of consecutive adult patients with COVID-19 admitted to our hospital over a 3-week period. Data on patient demographics, hematologic values, cross-sectional imaging examinations, and clinical outcomes (death and intubation) were collected. Imaging was reviewed for manifestations of coagulopathy. Multivariable logistic regression analyses were performed to assess associations of patient demographics, hematologic markers, and outcomes with the need for imaging and imaging manifestations of coagulopathy. RESULTS. Of 308 hospitalized patients with COVID-19, 142 (46%) underwent 332 cross-sectional imaging examinations. Of these, 37 (26%) had imaging results positive for coagulopathy. The most common imaging manifestations of coagulopathy were pulmonary embolus (n = 21) on contrast-enhanced CT or CTA, thrombus in the upper- or lower-extremity veins (n = 13) on Doppler ultrasound, end-organ infarction in the bowel (n = 4) and kidney (n = 4) on contrast-enhanced CT, and thrombus or parenchymal infarction in the brain (n = 2) on contrast-enhanced CTA or MRI with MRA. Among patients with imaging results positive for coagulopathy, eight (22%) had multisite involvement. Thrombi were multifocal in four of five patients with positive upper-extremity and three of eight patients with positive lower-extremity examination results and involved superficial veins, deep veins, or both. In multivariable analysis, intubation (p < .001) and prolonged prothrombin time (p = .04) were significantly associated with undergoing imaging. No patient variable was significantly associated with imaging results positive for coagulopathy (p > .05). CONCLUSION. Imaging commonly shows manifestations of coagulopathy in hospitalized patients with COVID-19. Over one-fifth of patients with such manifestations show multisite involvement. Clinical variables poorly predict which patients have positive imaging results, indicating a complementary role of imaging in detecting COVID-19-associated coagulopathy. CLINICAL IMPACT. In patients with COVID-19 with suspected systemic coagulopathy, pulmonary CTA, extremity Doppler ultrasound, contrast-enhanced abdominal CT, and contrast-enhanced brain MRI and MRA may all be appropriate in the absence of imaging contraindications.

Cerebellar Hemangioblastoma: Diagnostic Yield of Contrast-Enhanced Abdominal CT and Whole-Spine MRI as Initial Screening Imaging.

OBJECTIVE. The existing literature lacks research into the benefits of initial screening imaging for patients with cerebellar hemangioblastoma. We aimed to evaluate the diagnostic yield of initial screening imaging using abdominal CT and whole-spine MRI in patients with cerebellar hemangioblastoma. MATERIALS AND METHODS. This retrospective study included 117 consecutive patients with histopathologically confirmed, newly diagnosed cerebellar hemangioblastomas at a single tertiary hospital between January 2006 and October 2018. Patients underwent contrast-enhanced abdominal CT, whole-spine MRI, or both to detect abdominal and spinal lesions of von Hippel-Lindau disease. Diagnostic yields and false referral rates for initial screening imaging were determined. RESULTS. After exclusion of six patients who forewent any initial imaging, 111 patients were included (53 men [mean age ± SD, 51 ± 13 years] and 58 women [mean age, 43 ± 16 years]). The diagnostic yield of abdominal CT was 3.8% (4 of 105; 95% CI, 1.1-9.3%), whereas the false referral rate was 1.0% (1 of 105; 95% CI, 0.0-5.2%). For whole-spine MRI, the corresponding values were 5.6% (4 of 71; 95% CI, 1.6-13.8%) and 2.8% (2 of 71; 95% CI, 0.3-9.8%), respectively. The respective diagnostic yields in patients with a single cerebellar hemangioblastoma were both 0% (0 of 98 and 66, respectively). CONCLUSION. For patients with a single cerebellar hemangioblastoma, screening examinations with abdominal CT and whole-spine MRI are unnecessary before the results of genetic testing are available.

Diagnostic accuracy of FDG-PET/MRI versus pelvic MRI and thoracic and abdominal CT for detecting synchronous distant metastases in rectal cancer patients.

We compared the diagnostic accuracy of detecting distant metastases for baseline rectal cancer staging between PET/MRI and conventional staging (CS). This prospective study from November 2016 to April 2018 included 101 rectal adenocarcinoma patients for primary staging. These patients underwent whole-body PET/MRI in addition to CS (pelvic MRI and thoracic and abdominal contrast-enhanced CT). Different readers analyzed CS and PET/MRI findings for primary tumor, nodal, and metastatic staging. The presence, number, and location of metastases were recorded according to the organ involved (non-regional lymph nodes (LNs), liver, lungs, or others). Lesions were defined as positive, negative, or indeterminate. The number of lesions per organ was limited to 10. The McNemar test was used to compare the accuracies. PET/MRI exhibited a higher accuracy in detecting metastatic disease than CS in all patients (88.4% vs. 82.6%, p = 0.003) and in patients with extramural vascular invasion (EMVI) (88.9% vs. 85.5%, p = 0.013). The detection rate of PET/MRI was superior to that of CS for all lesions [84.1% vs. 68.9%, p = 0.001], as well as those in the liver (89.2% vs. 84.2%), non-regional LNs (90.0% vs. 36.7%), and lungs (76.4% vs. 66.9%). PET/MRI correctly classified 19/33 (57.5%) patients with indeterminate lesions on CS. PET/MRI yields higher accuracy than CS for detecting distant synchronous metastases in the baseline staging of patients with rectal cancer and EMVI. PET/MRI exhibited a higher detection rate than CS for identifying non-regional LNs, hepatic lesions, and pulmonary lesions as well as correctly classifying patients with indeterminate lesions. NCT02537340.

Integrating tumor and nodal radiomics to predict lymph node metastasis in gastric cancer

BackgroundTo develop and validate a radiomics method via integrating tumor and lymph node radiomics for the preoperative prediction of lymph node (LN) status in gastric cancer (GC). Materials and methodsWe retrospectively collected 170 contrast-enhanced abdominal CT images from GC patients. Five times repeated random hold-out experiment was employed. Tumor and nodal radiomics features were extracted from each individual tumor and LN respectively, and then multi-step feature selection was performed. The optimal tumor and nodal features were selected using Pearson correlation analysis and sequential forward floating selection (SFFS) algorithm. After feature fusion, the SFFS algorithm was used to develop radiomics signatures. The performance of the radiomics signatures developed based on logistic regression classifier was further analyzed and compared using the area under the receiver operating characteristic curve (AUC). ResultsThe AUC values, reported as mean ± standard deviation, were 0.9319 ± 0.0129 and 0.8546 ± 0.0261 for the training and validation cohorts respectively. The radiomic signatures could predict LN status, especially in T2-stage, diffuse-type and moderately/well differentiated GC. After integrating clinicopathologic information, the radiomic-clinicopathologic model (training cohort, 0.9432 ± 0.0129; validation cohort, 0.8764 ± 0.0322) showed a better discrimination capability than other radiomics models and clinicopathologic model. The radiomic-clinicopathologic model also showed superior performance to the gastroenterologist’ decision in all experiments, and outperformed the radiologist in some experiments. ConclusionOur proposed method presented good predictive performance and great potential for predicting LNM in GC. As a noninvasive preoperative prediction tool, it can be helpful for guiding the prognosis and treatment decision-making in GC patients.

Emerging Phenotype of Severe Acute Respiratory Syndrome-Coronavirus 2–associated Pancreatitis

Emerging Phenotype of Severe Acute Respiratory Syndrome-Coronavirus 2–associated Pancreatitis