CT findings in idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) and comparison to other colitides

PURPOSE

The purpose of this study is to determine computed tomography (CT) findings that aid in differentiating idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) from other colitides.

METHODS

Retrospective review of histiologic proven cases of IMHMV (n = 12) with contrast enhanced CT (n = 11) and/or computed tomography angiography (CTA) (n = 9) exams. Control groups comprised of CT of infectious colitis (n = 13), CT of inflammatory bowel disease (IBD) (n = 12), and CTA of other colitides (n = 13). CT exams reviewed by 2 blinded gastrointestinal radiologists for maximum bowel wall thickness, enhancement pattern, decreased bowel wall enhancement, submucosal attenuation value, presence and location of IMV occlusion, peripheral mesenteric venous occlusion, dilated pericolonic veins, subjective IMA dilation, maximum IMA diameter, maximum peripheral IMA branch diameter, ascites, and mesenteric edema. Presence of early filling veins was an additional finding evaluated on CTA exams.

RESULTS

Statistically significant CT findings of IMHMV compared to control groups included greater maximum bowel wall thickness, decreased bowel enhancement, IMV occlusion, and peripheral mesenteric venous occlusion (p < 0.05). Dilated pericolonic veins were seen more frequently in IMHMV compared to the infectious colitis group (64% versus 15%, p = 0.02). Additional statistically significant finding on CTA included early filling veins in IMHMV compared to the CTA control group (100% versus 46%, p = 0.008).

CONCLUSION

IMHMV is a rare chronic non-thrombotic ischemia predominantly involving the rectosigmoid colon. CT features that may aid in differentiating IMHMV from other causes of left-sided colitis include marked bowel wall thickening with decreased enhancement, IMV and peripheral mesenteric venous occlusion or tapering, and early filling of dilated veins on CTA.

Beyond squamous cell carcinoma: MRI appearance of uncommon anal neoplasms and mimickers

Anal cancer is an uncommon malignancy. In addition to squamous cell carcinoma, there are a variety of other less common malignancies and benign pathologies that may afflict the anal canal, with which abdominal radiologists should be familiar. Abdominal radiologists should be familiar with the imaging features that can help distinguish different rare anal tumors beyond squamous cell carcinoma and that can aid in diagnosis therefore help steer management. This review discusses these uncommon pathologies with a focus on their imaging appearance, management, and prognosis.

Imaging of Anal Squamous Cell Carcinoma: Survey Results and Expert Opinion from the Rectal and Anal Cancer Disease-Focused Panel of the Society of Abdominal Radiology

The role and method of image-based staging of anal cancer has evolved with the rapid development of newer imaging modalities and the need to address the rising incidence of this rare cancer. In 2014, the European Society of Medical Oncology mandated pelvic magnetic resonance imaging (MRI) for anal cancer and subsequently other societies such as the National Comprehensive Cancer Network followed suit with similar recommendations. Nevertheless, great variability exists from center to center and even within individual centers. Notably, this is in stark contrast to the imaging of the anatomically nearby rectal cancer. As participating team members for this malignancy, we embarked on a comprehensive literature review of anal cancer imaging to understand the relative merits of these new technologies which developed after computed tomography (CT), e.g., MRI and positron emission tomography/computed tomography (PET/CT). The results of this literature review helped to inform our next stage: questionnaire development regarding the imaging of anal cancer. Next, we distributed the questionnaire to members of the Society of Abdominal Radiology (SAR) Rectal and Anal Disease-Focused Panel, a group of abdominal radiologists with special interest, experience, and expertise in rectal and anal cancer, to provide expert radiologist opinion on the appropriate anal cancer imaging strategy. In our expert opinion survey, experts advocated the use of MRI in general (65% overall and 91-100% for primary staging clinical scenarios) and acknowledged the superiority of PET/CT for nodal assessment (52-56% agreement for using PET/CT in primary staging clinical scenarios compared to 30% for using MRI). We therefore support the use of MRI and PET and suggest further exploration of PET/MRI as an optimal combined evaluation. Our questionnaire responses emphasized the heterogeneity in imaging practice as performed at numerous academic cancer centers across the United States and underscore the need for further reconciliation and establishment of best imaging practice guidelines for optimized patient care in anal cancer.

Follow-up imaging of anal cancer after treatment

Anal cancer treatment response assessment can be challenging with both magnetic resonance imaging (MRI) and clinical evaluation considered essential. MRI, in particular, has shown to be useful for the assessment of treatment response, the detection of recurrent disease in follow up and surveillance, and the evaluation of possible post-treatment complications as well as complications from the tumor itself. In this review, we focus on the role of imaging, mainly MRI, in anal cancer treatment response assessment. We also describe the treatment complications that can occur, and the imaging findings associated with those complications.

Imaging of Small-Bowel Neuroendocrine Neoplasms: AJR Expert Panel Narrative Review

Neuroendocrine neoplasms (NENs) of the small bowel are typically slow-growing lesions that remain asymptomatic until reaching an advanced stage. Imaging modalities for lesion detection, staging, and follow-up in patients with known or suspected NEN include CT enterography, MR enterography, and PET/CT using a somatostatin receptor analog. FDG PET/CT may have a role in the evaluation of poorly differentiated NENs. Liver MRI, ideally with a hepatocyte-specific contrast agent, should be used in the evaluation of hepatic metastases. Imaging informs decisions regarding both surgical approaches and systematic therapy (specifically, peptide receptor radionuclide therapy). This AJR Expert Panel Narrative Review describes the multimodality imaging features of small-bowel NENs; explores the optimal imaging modalities for their diagnosis, staging, and follow-up; and discusses how imaging may be used to guide therapy.

Rectal cancer pelvic recurrence: imaging patterns and key concepts to guide treatment planning

For rectal cancer, MRI plays an important role in assessing extramural tumor spread and informs surgical planning. The contemporary standardized management of rectal cancer with total mesorectal excision guided by imaging-based risk stratification has dramatically improved patient outcomes. Colonoscopy and CT are utilized in surveillance after surgery to detect intraluminal and extramural recurrence, respectively; however, local recurrence of rectal cancer remains a challenge because postoperative changes such as fat necrosis and fibrosis can resemble tumor recurrence; additionally, mucinous adenocarcinoma recurrence may mimic fluid collection or abscess on CT. MRI and ¹⁸F-FDG PET are problem-resolving modalities for equivocal imaging findings on CT. Treatment options for recurrent rectal cancer include pelvic exenteration to achieve radical (R0 resection) resection and intraoperative radiation therapy. After pathologic diagnosis of recurrence, imaging plays an essential role for evaluating the feasibility and approach of salvage surgery. Patterns of recurrence can be divided into axial/central, anterior, lateral, and posterior. Some lateral and posterior recurrence patterns especially in patients with neurogenic pain are associated with perineural invasion. Cross-sectional imaging, especially MRI and ¹⁸F-FDG PET, permit direct visualization of perineural spread, and contribute to determining the extent of resection. Multidisciplinary discussion is essential for treatment planning of locally recurrent rectal cancer. This review article illustrates surveillance strategy after initial surgery, imaging patterns of rectal cancer recurrence based on anatomic classification, highlights imaging findings of perineural spread on each modality, and discusses how resectability and contemporary surgical approaches are determined based on imaging findings.

Imaging Review of Gastrointestinal Motility Disorders

The motor function of the gastrointestinal tract relies on the enteric nervous system, which includes neurons spanning from the esophagus to the internal anal sphincter. Disorders of gastrointestinal motility arise as a result of disease within the affected portion of the enteric nervous system and may be caused by a wide array of underlying diseases. The etiology of motility disorders may be primary or due to secondary causes related to infection or inflammation, congenital abnormalities, metabolic disturbances, systemic illness, or medication-related side effects. The symptoms of gastrointestinal dysmotility tend to be nonspecific and may cause diagnostic difficulty. Therefore, evaluation of motility disorders requires a combination of clinical, radiologic, and endoscopic or manometric testing. Radiologic studies including fluoroscopy, CT, MRI, and nuclear scintigraphy allow exclusion of alternative pathologic conditions and serve as adjuncts to endoscopy and manometry to determine the appropriate diagnosis. Additionally, radiologist understanding of clinical evaluation of motility disorders is necessary for guiding referring clinicians and appropriately imaging patients. New developments and advances in imaging techniques have allowed improved assessment and diagnosis of motility disorders, which will continue to improve patient treatment options. Online supplemental material is available for this article. ^©RSNA, 2022.

Adaptive and Robust Vessel Quantification in Contrast-Free Ultrafast Ultrasound Microvessel Imaging

The morphological features of vasculature in diseased tissue differ significantly from those in normal tissue. Therefore, vasculature quantification is crucial for disease diagnosis and staging. Ultrasound microvessel imaging (UMI) with ultrafast ultrasound acquisitions has been determined to have potential in clinical applications given its superior sensitivity in blood flow detection. However, the presence of spatial-dependent noise caused by a low imaging signal-to-noise ratio and incoherent clutter artifacts caused by moving hyperechoic scatterers degrades the performance of UMI and the reliability of vascular quantification. To tackle these issues, we proposed an improved UMI technique along with an adaptive vessel segmentation workflow for robust vessel identification and vascular feature quantification. A previously proposed sub-aperture cross-correlation technique and a normalized cross-correlation technique were applied to equalize the spatially dependent noise level and suppress the incoherent clutter artifact. A square operator and non-local means filter were then used to better separate the blood flow signal from residual background noise. On the de-noised ultrasound microvessel image, an automatic and adaptive vessel segmentation method was developed based on the different spatial patterns of blood flow signal and background noise. The proposed workflow was applied to a CIRS phantom, to a Doppler flow phantom and to an inflammatory bowel, kidney and liver, to validate its feasibility. Results revealed that automatic adaptive, and robust vessel identification performance can be achieved using the proposed method without the subjectivity caused by radiologists/operators.

Into the future: A pilot study combining imaging with molecular profiling to predict resectability in ovarian cancer

OBJECTIVE

We sought to determine the predictive value of combining tumor molecular subtype and computerized tomography (CT) imaging for surgical outcomes after primary cytoreductive surgery in advanced stage high-grade serous ovarian cancer (HGSOC) patients.

METHODS

We identified 129 HGSOC patients who underwent pre-operative CT imaging and post-operative tumor mRNA profiling. A continuous CT-score indicative of overall disease burden was defined based on six imaging measurements of anatomic involvement. Molecular subtypes were derived from mRNA profiling of chemo-naïve tumors and classified as mesenchymal (MES) subtype (36%) or non-MES subtype (64%). Fischer exact tests and multivariate logistic regression examined residual disease and surgical complexity.

RESULTS

Women with higher CT-scores were more likely to have MES subtype tumors (p = 0.014). MES subtypes and a high CT-score were independently predictive of macroscopic disease and high surgical complexity. In multivariate models adjusting for age, stage and American Society of Anesthesiologists (ASA) score, patients with a MES subtype and high CT-score had significantly elevated risk of macroscopic disease (OR = 26.7, 95% CI = [6.42, 187]) and were more likely to undergo high complexity surgery (OR = 9.53, 95% CI = [2.76, 40.6], compared to patients with non-MES tumor and low CT-score.

CONCLUSION

Preoperative CT imaging combined with tumor molecular subtyping can identify a subset of women unlikely to have resectable disease and likely to require high complexity surgery. Along with other clinical factors, these may refine predictive scores for resection and assist treatment planning. Investigating methods for pre-surgical molecular subtyping is an important next step.

Eosinophilic Disorders of the Gastrointestinal Tract and Associated Abdominal Viscera: Imaging Findings and Diagnosis

Eosinophilic gastrointestinal disorders (EGIDs) are inflammatory conditions of the gastrointestinal tract that are characterized by tissue eosinophilia and end-organ dysfunction or damage. Primary EGIDs are associated with atopy and other allergic conditions, whereas secondary EGIDs are associated with underlying systemic diseases or hypereosinophilic syndrome. Within the spectrum of EGIDs, eosinophilic esophagitis is the most prevalent. Eosinophilic gastroenteritis and eosinophilic colitis are relatively uncommon. Eosinophilic infiltration of the liver, biliary tree, and/or pancreas also can occur and mimic other inflammatory and malignant conditions. Although endoscopic evaluation is the method of choice for eosinophilic esophagitis, radiologic evaluation of the esophagus plays an important role in the assessment of disease severity. CT and MR enterography are the modalities of choice for demonstrating specific forms of eosinophilic gastroenteritis. CT and MRI are important in the detection of abdominal visceral involvement in EGIDs. Diagnosis is often challenging and relies on symptoms, imaging findings, histologic confirmation of tissue eosinophilia, and correlation with peripheral eosinophilia. Imaging is crucial for identifying characteristic organ-specific findings, although imaging findings are not specific. When promptly treated, EGIDs usually have a benign clinical course. However, a delayed diagnosis and associated surgical interventions have been associated with morbidity. Therefore, a radiologist's knowledge of the imaging findings of EGIDs in the appropriate clinical settings may aid in early diagnosis and thereby improve patient care. An overview of the clinical features and imaging findings of EGIDs and the eosinophilic disorders of associated abdominal viscera is provided. Online supplemental material is available for this article. ^©RSNA, 2022.

Defining normal pouch function in patients with ileal pouch-anal anastomosis: a pilot study

BACKGROUND

Most patients experience good functional outcomes following ileal pouch-anal anastomosis (IPAA) for ulcerative colitis.

AIM

We aimed to determine if asymptomatic patients with an IPAA had findings consistent with normal defecation on standard objective anorectal tests.

METHODS

Patients 18-65 years old with IPAA and self-reported healthy pouch function were recruited. Patients with chronic pouchitis, Crohn's disease, anastomotic stricture, or indication for IPAA other than ulcerative or indeterminate colitis were excluded. Patients underwent an interview with an abbreviated Rome Questionnaire followed by high-resolution ano-pouch manometry, balloon expulsion test, pouch barostat, and magnetic resonance (MR) defecography.

RESULTS

Twenty patients completed all testing. Six patients were excluded from the final analysis due to symptoms suggestive of pouch evacuation disorder on the abbreviated Rome Questionnaire (n = 2), structural abnormality on MR imaging (n = 3), or both (n = 1). Of the remaining 14 patients, mean anal resting pressure during high-resolution manometry was 72 ± 16 mmHg, mean anal squeeze pressure was 247 ± 69 mmHg, and mean pouch-anal gradient during the simulated evacuation was -27 ± 37 mmHg. The meantime to balloon expulsion was 54 seconds. During dynamic MR defecography, the mean descent of ano-pouch junction was 2.6 cm, and mean pouch evacuation was 44.5% and 74.2% pre- and posttoilet phase, respectively.

CONCLUSIONS

A substantial proportion of patients with IPAA and self-reported healthy pouch function have anatomic and/or functional abnormalities of the pouch. In asymptomatic IPAA patients with an anatomically normal pouch, we have proposed normal parameters for high-resolution ano-pouch manometry, time to balloon expulsion, pouch barostat, and MR defecography.

Modest agreement between magnetic resonance and pathological tumor regression after neoadjuvant therapy for rectal cancer in the real world

Magnetic Resonance Imaging (MRI) is routinely used for preoperative tumor staging and to assess response to therapy in rectal cancer patients. The aim of this study was to evaluate the accuracy of MRI based restaging after neoadjuvant CRT in predicting pathologic response. This multicenter cohort study included adult patients with histologically confirmed locally advanced rectal adenocarcinoma treated with neoadjuvant CRT followed by curative intent elective surgery between January 2014 and December 2019 at four academic high-volume institutions. Magnetic resonance tumor regression grade (mrTRG) and pathologic tumor regression grade (pTRG) were reviewed and compared for all the patients. The agreement between radiologist and pathologist was assessed with the weighted k test. Risk factors for poor agreement were investigated using logistic regression. A total of 309 patients were included. Modest agreement was found between mrTRG and pTRG when regression was classified according to standard five-tier systems (k=0.386). When only two categories were considered for each regression system, (pTRG 0-3 vs. pTRG 4; mrTRG 2-5 vs. mrTRG 1) an accuracy of 78% (IC 95% 0.73-0.83) was found between radiologic and pathologic assessment with a k value of 0.185.The logistic regression model revealed that "T3 greater than 5mm extent" was the only variable significantly impacting on disagreement (OR 0.33, 95% CI 0.15-0.68, p=0.0034). Modest agreement exhists between mrTRG and pTRG. The chances of appropriate assessment of the regression grade after neoadjuvant CRT appear to be higher in case of a T3 tumor with at least 5mm extension in the mesorectal fat at the pre-treatment MRI. This article is protected by copyright. All rights reserved.

Predicting Risk of Surgery in Patients With Small Bowel Crohn's Disease Strictures Using Computed Tomography and Magnetic Resonance Enterography

BACKGROUND

We aimed to determine if patient symptoms and computed tomography enterography (CTE) and magnetic resonance enterography (MRE) imaging findings can be used to predict near-term risk of surgery in patients with small bowel Crohn's disease (CD).

METHODS

CD patients with small bowel strictures undergoing serial CTE or MRE were retrospectively identified. Strictures were defined by luminal narrowing, bowel wall thickening, and unequivocal proximal small bowel dilation. Harvey-Bradshaw index (HBI) was recorded. Stricture observations and measurements were performed on baseline CTE or MRE and compared to with prior and subsequent scans. Patients were divided into those who underwent surgery within 2 years and those who did not. LASSO (least absolute shrinkage and selection operator) regression models were trained and validated using 5-fold cross-validation.

RESULTS

Eighty-five patients (43.7 ± 15.3 years of age at baseline scan, majority male [57.6%]) had 137 small bowel strictures. Surgery was performed in 26 patients within 2 years from baseline CTE or MRE. In univariate analysis of patients with prior exams, development of stricture on the baseline exam was associated with near-term surgery (P = .006). A mathematical model using baseline features predicting surgery within 2 years included an HBI of 5 to 7 (odds ratio [OR], 1.7 × 105; P = .057), an HBI of 8 to 16 (OR, 3.1 × 105; P = .054), anastomotic stricture (OR, 0.002; P = .091), bowel wall thickness (OR, 4.7; P = .064), penetrating behavior (OR, 3.1 × 103; P = .096), and newly developed stricture (OR: 7.2 × 107; P = .062). This model demonstrated sensitivity of 67% and specificity of 73% (area under the curve, 0.62).

CONCLUSIONS

CTE or MRE imaging findings in combination with HBI can potentially predict which patients will require surgery within 2 years.

Dual contrast liver MRI: a pictorial illustration

Liver magnetic resonance imaging (MRI) is a commonly performed imaging technique with multiple indications and applications. There are two general groups of contrast agents used when imaging the liver, extracellular contrast agents (ECA) and hepatobiliary agents (HBA), each of which has its own advantages and limitations. Liver MRI with ECA provides excellent information on abdominal vasculature and better quality multi-phasic studies for characterization of focal liver lesions. HBA improves lesion detection, provides information regarding liver function and can be helpful for evaluating biliary tree anatomy, excretion, anastomotic stenoses, or leaks. Most liver MRI studies are usually performed with one agent, however in some cases, a second study is performed with another agent to obtain additional information or confirm the findings in the first study. Administering both agents in a single exam can potentially eliminate the need for additional imaging in certain situations. In this pictorial review, the techniques and indications for dual contrast MRI will be detailed with multiple demonstrative examples.

MRI-detected extramural venous invasion of rectal cancer: Multimodality performance and implications at baseline imaging and after neoadjuvant therapy

MRI is routinely used for rectal cancer staging to evaluate tumor extent and to inform decision-making regarding surgical planning and the need for neoadjuvant and adjuvant therapy. Extramural venous invasion (EMVI), which is intravenous tumor extension beyond the rectal wall on histopathology, is a predictor for worse prognosis. T2-weighted images (T2WI) demonstrate EMVI as a nodular-, bead-, or worm-shaped structure of intermediate T2 signal with irregular margins that arises from the primary tumor. Correlative diffusion-weighted images demonstrate intermediate to high signal corresponding to EMVI, and contrast enhanced T1-weighted images demonstrate tumor signal intensity in or around vessels. Diffusion-weighted and post contrast images may increase diagnostic performance but decrease inter-observer agreement. CT may also demonstrate obvious EMVI and is potentially useful in patients with a contraindication for MRI. This article aims to review the spectrum of imaging findings of EMVI of rectal cancer on MRI and CT, to summarize the diagnostic accuracy and inter-observer agreement of imaging modalities for its presence, to review other rectal neoplasms that may cause EMVI, and to discuss the clinical significance and role of MRI-detected EMVI in staging and restaging clinical scenarios.

The utility of a dual-phase, dual-energy CT protocol in patients presenting with overt gastrointestinal bleeding

Background

Due to their easy accessibility, CT scans have been increasingly used for investigation of gastrointestinal (GI) bleeding.

Purpose

To estimate the performance of a dual-phase, dual-energy (DE) GI bleed CT protocol in patients with overt GI bleeding in clinical practice and examine the added value of portal phase and DE images.

Materials and Methods

Consecutive patients with GI bleeding underwent a two-phase DE GI bleed CT protocol. Two gastroenterologists established the reference standard. Performance was estimated using clinical CT reports. Three GI radiologists rated confidence in GI bleeding in a subset of 62 examinations, evaluating first mixed kV arterial images, then after examining additional portal venous phase images, and finally after additional DE images (virtual non-contrast and virtual monoenergetic 50 keV images).

Results

52 of 176 patients (29.5%) had GI bleeding by the reference standard. The overall sensitivity, specificity, and positive and negative predictive values of the CT GI bleed protocol for detecting GI bleeding were 65.4%, 89.5%, 72.3%, and 86.0%, respectively. In patients with GI bleeding, diagnostic confidence of readers increased after adding portal phase images to arterial phase images (p = 0.002), without additional benefit from dual energy images. In patients without GI bleeding, confidence in luminal extravasation appropriately decreased after adding portal phase, and subsequently DE images (p = 0.006, p = 0.018).

Conclusion

A two-phase DE GI bleed CT protocol had high specificity and negative predictive value in clinical practice. Portal venous phase images improved diagnostic confidence in comparison to arterial phase images alone. Dual-energy images further improved radiologist confidence in the absence of bleeding.

Early Cholangiocarcinoma Detection With Magnetic Resonance Imaging Versus Ultrasound in Primary Sclerosing Cholangitis

BACKGROUND AND AIMS

Early detection of perihilar cholangiocarcinoma (CCA) among patients with primary sclerosing cholangitis (PSC) is important to identify more people eligible for curative therapy. While many recommend CCA screening, there are divergent opinions and limited data regarding the use of ultrasound or magnetic resonance imaging (MRI) for early CCA detection, and it is unknown whether there is benefit in testing asymptomatic individuals. Our aims were to assess the diagnostic performances and prognostic implications of ultrasound and MRI-based CCA detection.

APPROACH AND RESULTS

This is a multicenter review of 266 adults with PSC (CCA, n = 120) who underwent both an ultrasound and MRI within 3 months. Images were re-examined by radiologists who were blinded to the clinical information. Respectively, MRI had a higher area under the curve compared with ultrasound for CCA detection: 0.87 versus 0.70 for the entire cohort; 0.81 versus 0.59 for asymptomatic individuals; and 0.88 versus 0.71 for those listed for CCA transplant protocol. The absence of symptoms at CCA diagnosis was associated with improved 5-year outcomes including overall survival (82% vs. 46%, log-rank P < 0.01) and recurrence-free survival following liver transplant (89% vs. 65%, log-rank P = 0.04). Among those with asymptomatic CCA, MRI detection (compared with ultrasound) was associated with reduction in both mortality (hazard ratio, 0.10; 95% confidence interval, 0.01-0.96) and CCA progression after transplant listing (hazard ratio, 0.10; 95% confidence interval, 0.01-0.90). These benefits continued among patients who had annual monitoring and PSC for more than 1 year before CCA was diagnosed.

CONCLUSIONS

MRI is superior to ultrasound for the detection of early-stage CCA in patients with PSC. Identification of CCA before the onset of symptoms with MRI is associated with improved outcomes.

The diagnosis and outcome of Krukenberg tumors

Background

Accurate diagnostic tools are crucial to distinguish patients with Krukenberg tumors from those with ovarian cancers before decision on initial management. To address this unmet need, we aimed to evaluate the diagnostic utility of clinical, biochemical, and radiographic factors in this patient population.

Methods

Patients with Krukenberg tumors or primary ovarian cancers were retrospectively identified from institutional cancer registry. Kaplan-Meier method and Cox proportional hazards models were used for survival analysis. Logistic regression evaluated clinical, biochemical, and radiographic factors; residual deep neural network model evaluated features in computed tomography images as predictors to distinguish Krukenberg tumors from ovarian cancers. Model performance was summarized as accuracy and area under the receiver operating characteristic curve (AUC).

Results

This study included 214 patients with Krukenberg tumors with median age of 52 years. Among 104 (48.6%) patients with colorectal cancer, those who received palliative surgery had significantly higher median overall survival (48.1 versus 30.6 months, P=0.015) and progression-free survival (22.2 versus 6.7 months, P<0.001) than those with medical management only. The accuracy of radiology reports to make either diagnosis of Krukenberg tumors or primary ovarian cancers was 60.7%. In contrast, multivariable logistic regression model with age [odds ratio (OR) 2.98, P<0.001], carbohydrate antigen 125 (OR 1.57, P=0.004), and carcinoembryonic antigen (OR 0.03, P=0.031) had 87.5% [95% confidence interval (CI): 75.0-100.0%] accuracy with AUC 0.96 (95% CI: 0.87-1.00). The neural network model had 62.8% (95% CI: 51.8-74.5%) accuracy with AUC of 0.61 (95% CI: 0.53-0.72).

Conclusions

We developed a diagnostic model with clinical and biochemical features to distinguish Krukenberg tumors from primary ovarian cancers with promising accuracy.

Magnetic resonance imaging features of small-duct primary sclerosing cholangitis

PURPOSE

To evaluate the biliary tree and hepatic parenchymal findings on magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) in small-duct primary sclerosing cholangitis (SD-PSC).

METHODS

Thirty-nine patients with biopsy-proven primary sclerosing cholangitis (PSC) without any bile duct abnormality on MRCP (n = 15) or ERCP (n = 24) at the time of diagnosis were identified. Follow-up MRCP was available in 36/39 patients (12/15 Baseline MRCP group and 24 Baseline ERCP group). Two radiologists in consensus assessed the MRI/MRCP findings. The baseline MRI/MRCP of 15 SD-PSC patients was compared with MRI/MRCP of 15 normal healthy potential liver donors (Control group). Comparisons were made between SD-PSC patients and the Control group, and between baseline and follow-up MRI/MRCP findings in the SD-PSC patients.

RESULTS

In the 15 Baseline MRCP SD-PSC subjects, the biliary tree was normal with a trend of larger bile ducts compared to the Control group. Periductal enhancement (arterial phase: 70%, 7/10; delayed phase: 90%, 9/10), heterogeneous parenchymal signal on T2-weighted (53%, 8/15) and post contrast-enhanced images (70%, 7/10), and enlarged periportal lymph nodes (73%, 11/15) were frequently present in patients with SD-PSC. Eight (33%) of 24 SD-PSC patients who had normal MRCP at baseline MRCP or initial follow-up MRCP after normal baseline ERCP showed large-duct PSC (LD-PSC) features on follow-up and the 10-year cumulative incidence for progression to LD-PSC rate was 8.5%.

CONCLUSION

SD-PSC patients have a normal biliary tree but frequently have peribiliary enhancement, abnormal parenchymal signal intensity, and periportal lymphadenopathy. One-third shows progression to LD-PSC on follow-up.

Endometriosis in the postmenopausal female: clinical presentation, imaging features, and management

Postmenopausal endometriosis is an important clinical entity which is likely under-recognized and in which the Radiologist can play a valuable role. In this review, we describe the clinical presentation and management of postmenopausal endometriosis, appraising the literature and providing case examples. Persons with postmenopausal endometriosis may present with symptoms including pelvic pain or dyschezia, but endometriosis may also be an asymptomatic, incidental finding. Women may or may not have a prior history of endometriosis or a history of symptoms consistent with it. Therapies and conditions which increase exogenous or endogenous estrogen, respectively, increase the risk. Endometriosis can be found in different locations throughout the body, and the possibility of malignancy should be assessed, especially in the postmenopausal population, where age increases cancer risk. Treatment may involve surgery or medical interventions. Guidelines describing appropriate imaging surveillance in these patients are lacking. In the postmenopausal population, Radiologists need to consider endometriosis as a diagnosis, recommend appropriate exams such as MRI and US, and suggest endometriosis-associated malignancies when appropriate, based on classic morphologic features.

Imaging Findings of Ileal Inflammation at Computed Tomography and Magnetic Resonance Enterography: What do They Mean When Ileoscopy and Biopsy are Negative?

BACKGROUND AND AIMS

Our goal was to determine the importance of ileal inflammation at computed tomography or magnetic resonance enterography in Crohn's disease patients with normal ileoscopy.

METHODS

Patients with negative ileoscopy and biopsy within 30 days of CT or MR enterography showing ileal inflammation were included. The severity [0-3 scale] and length of inflammation within the distal 20 cm of the terminal ileum were assessed on enterography. Subsequent medical records were reviewed for ensuing surgery, ulceration at ileoscopy, histological inflammation, or new or worsening ileal inflammation or stricture on enterography. Imaging findings were classified as: Confirmed Progression [subsequent surgery or radiological worsening, new ulcers at ileoscopy or positive histology]; Radiologic Response [decreased inflammation with medical therapy]; or Unlikely/Unconfirmed Inflammation.

RESULTS

Of 1471 patients undergoing enterography and ileoscopy, 112 [8%] had imaging findings of inflammation with negative ileoscopy, and 88 [6%] had negative ileoscopy and ileal biopsy. Half [50%; 44/88] with negative biopsy had moderate/severe inflammation at enterography, with 45%, 32% and 11% having proximal small bowel inflammation, stricture or fistulas, respectively. Two-thirds with negative biopsy [67%; 59/88] had Confirmed Progression, with 68%, 70% and 61% having subsequent surgical resection, radiological worsening or ulcers at subsequent ileoscopy, respectively. Mean length and severity of ileal inflammation in these patients was 10 cm and 1.6. Thirteen [15%] patients had Radiologic Response, and 16 [18%] had Unlikely/Unconfirmed Inflammation.

CONCLUSION

Crohn's disease patients with unequivocal imaging findings of ileal inflammation at enterography despite negative ileoscopy and biopsy are likely to have active inflammatory Crohn's disease. Disease detected by imaging may worsen over time or respond to medical therapy.

Quantitative Inflammation Assessment for Crohn Disease Using Ultrasensitive Ultrasound Microvessel Imaging: A Pilot Study

OBJECTIVES

Crohn disease (CD) is a chronic inflammation in the digestive tract that affects millions of Americans. Bowel vascularity has important diagnostic information because inflammation is associated with blood flow changes. We recently developed an ultrasensitive ultrasound microvessel imaging (UMI) technique with high vessel sensitivity. This study aimed to evaluate the feasibility of UMI to assist CD detection and staging.

METHODS

Ultrasound microvessel imaging was performed on 76 bowel wall segments from 48 symptomatic patients with CD. Clinically indicated computed tomographic/magnetic resonance enterography was used as the reference standard. The vessel-length ratio (VLR, the number of vessel pixels in the bowel wall segment normalized to the segment length) was derived in both conventional color flow imaging (CFI) and UMI to quantitatively stage disease activity. Receiver operating characteristic curves were then analyzed between different disease groups.

RESULTS

The VLR-CFI and VLR-UMI detected similar correlations between vascularization and disease activity: severe inflammation had a higher VLR than normal/mildly inflamed bowels (P < .05). No significant difference was found between quiescent and mild CD due to the small sample size. The VLR-CFI had more difficulties in distinguishing quiescent versus mild CD compared to the VLR-UMI. After combining the VLR-UMI with thickness, in the receiver operating characteristic curve analysis, the areas under the curves (AUCs) improved to AUC₁ = 0.996 for active versus quiescent CD, AUC₂ = 0.978 for quiescent versus mild CD, and AUC₃ = 0.931 for mild versus severe CD, respectively, compared to those using thickness alone (AUC₁ = 0.968; P = .04; AUC₂ = 0.919; P = .16; AUC₃ = 0.857; P = .01).

CONCLUSIONS

Ultrasound microvessel imaging offers a safe and cost-effective tool for CD diagnosis and staging, which may potentially assist disease activity classification and therapy efficacy evaluation.

The evolving role of imaging for small bowel neuroendocrine neoplasms: estimated impact of imaging and disease-free survival in a retrospective observational study

PURPOSE

To determine how small bowel neuroendocrine neoplasms (SBNEN's) are diagnosed and examine the effect of CT enterography (CTE) on diagnosis and rates of disease-free survival.

METHODS

Histopathologically-confirmed SBNEN's diagnosed at our institution between 1996 and 2016 were identified. Clinical presentation, radiology, endoscopy, surgery, and pathology reports were reviewed and compared between consecutive 5-year periods.

RESULTS

Of the 178 SBNEN initially diagnosed at our institution, the incidence increased 12-fold from 9 (during 1996-2000) to 114 (during 2011-2016). Comparing the first 5 to the last 5 years, GI bleeding and abdominal pain increased significantly as indications (with both increasing from 0 to > 25%, p ≤ 0.023). Initial diagnosis by radiology increased 2-fold [from 33% (n = 3) to 66% (n = 75); p = 0.263]. Detection of a small bowel mass and the suggestion that SBNEN was present varied significantly between imaging modalities (p < 0.0001; CTE - 95% (52/55) and 91% (50/55) vs. abdominal CT 45% (37/85) and 35% (29/85), respectively). Recurrence rates increased with SBNEN size (p = 0.012; e.g., of SBNEN diagnosed by endoscopy, 18% of SBNEN measuring 0.6 ± 0.3 cm recurred vs. 75% measuring 3.7 ± 1.0 cm). Rates of disease-free survival, and the incidence of local and liver metastases were decreased when tumors were first identified by CTE rather than other CT/MR imaging modalities (p = 0.0034, 0.0475, and 0.0032, respectively).

CONCLUSION

There has been a dramatic increase in SBNENs detected by CTE and endoscopy over the last 20 years. SBNEN's detected by CTE and small tumors detected at endoscopy have longer disease-free survival after surgical resection.

Portal Hypertensive Cholangiopathy, Which Masquerades as an Acute Portal Vein Thrombosis

Portal hypertensive cholangiopathy is a rare complication of extrahepatic portal vein obstruction and portal cavernoma. It is usually asymptomatic but may be associated with jaundice, biliary colic, and fever. Abdominal sonography and Doppler are ideal initial diagnostic modalities, followed by magnetic resonance cholangiopancreatography or endoscopic retrograde cholangiopancreatography. These imaging modalities are important if an intervention is planned for the management of portal hypertension and for relieving biliary obstruction. If computed tomography (CT) is performed in isolation, it may be challenging to distinguish this entity from acute on chronic portal vein thrombosis. The diagnostic results should be interpreted cautiously. This case report of an abdomen CT performed on a patient with a history of portal vein thrombosis masqueraded as an acute on chronic portal vein thrombosis with cavernous collaterals. Doppler confirmed the diagnosis of portal hypertensive cholangiopathy. Correlation with clinical symptoms and Doppler may be necessary to distinguish portal hypertensive cholangiopathy from acute portal vein thrombus.

Malabsorption Syndromes, Vasculitis, and Other Uncommon Diseases

MR enterography is frequently ordered for patients with suspected small bowel disorders. In this article, disease-causing malabsorption, vasculitides, and some of the less common small bowel diseases are reviewed. The clinical presentations, diagnostic criteria, and imaging findings of these diseases are discussed. Because the imaging findings in several small bowel diseases are nonspecific and/or overlap, radiologists must correlate clinical data with imaging to develop a narrower differential diagnosis. The unique or characteristic findings in certain diseases are also emphasized.

Rectal cancer lexicon: consensus statement from the society of abdominal radiology rectal & anal cancer disease-focused panel

Standardized terminology is critical to providing consistent reports to referring clinicians. This lexicon aims to provide a reference for terminology frequently used in rectal cancer and reflects the consensus of the Society of Abdominal Radiology Disease Focused Panel in Rectal cancer. This lexicon divided the terms into the following categories: primary tumor staging, nodal staging, treatment response, anal canal anatomy, general anatomy, and treatments.

Impact of a Multidisciplinary eBoard on the Management of Patients With Complex Inflammatory Bowel Disease

Background

We aim to assess the impact of a multidisciplinary inflammatory bowel disease (IBD) conference on the management of patients with complex IBD.

Methods

Data were collected during each conference from February 2017 through October 2018 with chart review performed at 6 months to determine if conference recommendations were successfully implemented.

Results

Eighty-five patients were discussed. The presenting diagnosis was changed by 11.8%. Recommendations for further testing, medical therapy, and surgery were successfully implemented in 77.1%, 98.1%, and 88.4%, respectively.

Conclusions

This study supports the role of IBD multidisciplinary conferences in the management of patients with complex IBD.

Judging the J pouch: a pictorial review

Restorative total proctocolectomy with ileal pouch-anal anastomosis is the surgery of choice for patients with medically refractory ulcerative colitis, ulcerative colitis with high-grade dysplasia or multi-focal low-grade dysplasia, and for patients with familial adenomatous polyposis. The natural history of the surgery is favorable, and patients generally experience improved quality of life and acceptable long-term functional outcome. However, some patients experience significant long-term morbidity from early and/or late pouch-related complications. When complications arise, radiologists must understand the advantages and disadvantages of the various imaging modalities that can be used to assess the pouch. Radiologist familiarity with the surgical technique, pouch anatomy, and imaging appearance of the various potential early and late complications will help facilitate appropriate clinical and surgical decision-making. This review provides an anatomic-based imaging review of the pouch and pouch-related complications, including numerous illustrative fluoroscopic and cross-sectional imaging examples.

Non-alcoholic fatty liver disease-associated hepatocellular carcinoma: effect of hepatic steatosis on major hepatocellular carcinoma features at MRI

OBJECTIVE:

To evaluate the effect of hepatic steatosis on LI-RADS® major features at MRI in patients with non-alcoholic fatty liver disease (NAFLD)-associated hepatocellular carcinoma (HCC).

METHODS:

HCC and liver parenchyma features at MRI from 48 consecutive patients with NAFLD and histology proven HCC (mean ± SD; 4.5 ± 3.4 cm) were independently reviewed by three radiologists. Inter-rater agreement was determined by prevalence/bias-adjusted kappa. Hepatic fat signal fraction (FS%) was independently calculated. HCC features were compared by FS% at MRI using logistic regression analysis and histologic steatosis grade using Cochran-Armitage test for trend, stratified by cirrhotic liver morphology or histologic fibrosis stage. Receiver operating characteristic curves were generated to determine the sensitivity and specificity for major HCC features by FS%.

RESULTS:

Major HCC features included arterial phase hyperenhancement (APHE) in 45 (93%), portal venous phase washout (PVWO) in 30 (63%), delayed phase washout (DPWO) in 38 (79%) and enhancing "capsule" in 34 (71%). Cirrhotic morphology was present in 22 (46%). Inter-rater agreement was 0.75 for APHE, 0.42-0.58 for PVWO, 0.58-0.71 for DPWO and 0.38-0.67 for enhancing "capsule". There was an 18%, 14% and 22% increase in the odds of absent PVWO, DPWO and capsule appearance for every 1% increase in hepatic FS% in patients with non-cirrhotic liver morphology (p = 0.011, 0.040 and 0.029, respectively). Hepatic FS% ≥ 14.8% had a sensitivity and specificity of 64 and 100% for absent PVWO and 71 and 90% for absent DPWO in patients with non-cirrhotic liver morphology.

CONCLUSION:

Absent washout and capsule appearance are associated with increasing hepatic steatosis in patients with non-cirrhotic, NAFLD-associated HCC.

ADVANCES IN KNOWLEDGE:

In patients with non-cirrhotic, non-alcoholic fatty liver disease (NAFLD)-associated hepatocellular carcinoma (HCC), absent HCC washout and capsule appearance are associated with increasing hepatic steatosis, thereby potentially impacting the noninvasive imaging diagnosis of HCC in these patients. Lack of washout or capsule appearance in steatotic livers at MRI may require alternative criteria for the diagnosis of HCC in patients with non-cirrhotic NAFLD.

Computed Tomography Enterography

Computed tomography (CT) enterography is a noninvasive imaging modality with superb spatial and temporal resolution, specifically tailored to evaluate the small bowel. It has several advantages over other radiologic and optical imaging modalities, all of which serve as complementary investigations to one another. This article describes CTE technique, including dose reduction techniques, special considerations for the pediatric population, common technical and interpretive pitfalls, and reviews some of the more common small bowel entities seen with CTE.

Predictors of Durability of Radiological Response in Patients With Small Bowel Crohn's Disease

BACKGROUND

The long-term significance of radiological transmural response (TR) as a treatment goal at the first follow-up scan in small bowel Crohn's disease (CD) has been previously shown. We examined the durability of a long-term strategy of treating to a target of radiological TR and the influence of baseline predictors on the maintenance of TR.

METHODS

Small bowel CD patients between January 1, 2002, and December 31, 2014, were identified with serial computed tomography enterography (CTE)/magnetic resonance enterography (MRE) before and after initiation of therapy or on maintenance therapy. Overall TR (inflammatory lesions with/without strictures) w1as characterized by abdominal radiologists in up to 5 small bowel lesions per patient at each serial scan until last follow-up or small bowel resection, as response, partial response, or nonresponse. The rate of conversion between TR states and transition to surgery, including the effect of baseline patient/disease characteristics, was examined using a multistate model (mstate R-package).

RESULTS

CD patients (n = 150, 705 CTE/MRE) with a median of 4 CTE/MRE during 4.6 years of follow-up, 49% with ileal-only distribution, had 260 examined bowel segments. Conversion from response to partial response/nonresponse was 37.4% per year of follow-up with no transitions seen directly from response to surgery. Current smoking status (hazard ratio [HR], 2.2; 95% confidence interval [CI], 1.1-4.3) and internal penetrating disease at baseline scan (HR, 2.2; 95% CI, 1.2-4.1) were associated with a 2-fold increased risk of transition from partial response/nonresponse to surgery.

CONCLUSIONS

Achievement and maintenance of radiological response is associated with avoidance of small bowel surgery. Continued follow-up with CTE/MRE is recommended to identify loss of response, especially in current smokers and patients with internal penetrating disease at baseline CTE/MRE.

Clinical significance of enlarged cardiophrenic lymph nodes in advanced ovarian cancer: Implications for survival

OBJECTIVE

Advanced ovarian cancer (OC) commonly spreads to cardiophrenic lymph nodes (CPLNs), and is often visible on preoperative imaging. We investigated the prognostic significance of abnormal CPLNs in OC detected by preoperative CT scans using three different definitions.

METHODS

Patients undergoing primary debulking surgery for stage IIIC/IV with residual disease (RD) ≤1.0cm and a preoperative abdominopelvic CT scan available were included. Scans were reviewed by two blinded radiologists. We characterized abnormal CPLNs using three different definitions: i) qualitative assessment score (QAS); ii) nodes >7mm on the short axis; or, iii) nodes ≥10mm on the short axis. We compared overall survival (OS) using the log-rank test.

RESULTS

Of the 253 patients (mean age 64.0years), 136 had no gross residual disease (NGR) and 117 had RD. By the QAS definition, CPLNs were abnormal in 28 (11.1%) patients and removed in one case. Among patients with NGR, presence of abnormal CPLNs was associated with worse OS (median OS, 38.4 vs. 69.6months, p=0.08). We observed no association between abnormal CPLNs and OS among patients with RD (median OS, 37.5 vs. 28.5months, p=0.49). OS was significantly better in NGR group without abnormal CPLNs (median OS for NGR vs. RD, 69.6 vs. 28.5months, p<0.001); however, there was no difference in OS between patients with NGR versus RD when abnormal CPLNs were present (median OS, 38.4 vs. 37.5months, p=0.99). Lack of benefit from NGR when abnormal CPLNs were present was observed for all three definitions tested.

CONCLUSION

Abnormal CPLNs are an important predictor of survival in advanced stage OC. Management of abnormal CPLNs should be considered in treatment planning when the goal is NGR.

MR Imaging of Perianal Crohn Disease

Pelvic magnetic resonance (MR) imaging is currently the standard for imaging perianal Crohn disease. Perianal fistulas are a leading cause of patient morbidity because closure often requires multimodality treatments over a prolonged period of time. This review summarizes clinically relevant anal sphincter anatomy, imaging methods, classification systems, and treatment objectives. In addition, the MR appearance of healing perianal fistulas and fistula complications is described. Difficult imaging tasks including the assessment of rectovaginal fistulas and ileoanal anastomoses are highlighted, along with illustrative cases. Emerging innovative treatments for perianal Crohn disease are now available and have the promise to better control sepsis and maintain fecal continence. Different treatment modalities are selected based on fistula anatomy, patient factors, and management goals (closure versus sepsis control). Radiologists can help maximize patient care by being familiar with MR imaging features of perianal Crohn disease and knowledgeable about what features may influence therapy decisions. ^© RSNA, 2017 Online supplemental material is available for this article.

Impact of CT enterography on the diagnosis of small bowel gastrointestinal stromal tumors

OBJECTIVE

Our purpose is to determine the impact of CT enterography on small bowel gastrointestinal stromal tumor (GIST) detection and biologic aggressiveness, and to identify any imaging findings that correlate with biologic aggressiveness.

METHODS

Records of patients with histologically confirmed small bowel GISTs who underwent CT imaging were reviewed. Biologic aggressiveness was based on initial histologic grading (very low, low, intermediate, high grade; or malignant), with upgrade to malignant category if local or distant metastases developed during clinical follow-up. Imaging indications, findings, and type of CT exam were compared with the biologic aggressiveness.

RESULTS

111 small bowel GISTs were identified, with suspected small bowel bleeding being the most common indication (45/111; 40.5%). While the number of malignant GISTs diagnosed by CT remained relatively constant (2-3 per year), the number of non-malignant GISTs increased substantially (mean 1.5/year, 1998-2005; 8.4/year, 2006-2013). In patients with suspected small bowel bleeding, CT enterography identified 33 GISTs (7/33, 21% malignant) compared to 12 GISTs by abdominopelvic CT (6/12, 50% malignant; p < 0.03). Tumor size (p < 0.0001), internal necrosis (p = 0.005), internal air or enteric contrast (p ≤ 0.021), and ulceration (p ≤ 0.021) were significantly associated with high-grade and malignant tumors, and irregular or invasive tumor borders (p < 0.01) was associated with malignant tumors.

CONCLUSION

The detection of small bowel GISTs can increase due to the use of CT enterography in patients with suspected small bowel bleeding. The large majority of small bowel GISTs detected by CT enterography are not malignant.

Validation of a Projection-domain Insertion of Liver Lesions into CT Images

RATIONALE AND OBJECTIVES

The aim of this study was to validate a projection-domain lesion-insertion method with observer studies.

MATERIALS AND METHODS

A total of 51 proven liver lesions were segmented from computed tomography images, forward projected, and inserted into patient projection data. The images containing inserted and real lesions were then reconstructed and examined in consensus by two radiologists. First, 102 lesions (51 original, 51 inserted) were viewed in a randomized, blinded fashion and scored from 1 (absolutely inserted) to 10 (absolutely real). Statistical tests were performed to compare the scores for inserted and real lesions. Subsequently, a two-alternative-forced-choice test was conducted, with lesions viewed in pairs (real vs. inserted) in a blinded fashion. The radiologists selected the inserted lesion and provided a confidence level of 1 (no confidence) to 5 (completely certain). The number of lesion pairs that were incorrectly classified was calculated.

RESULTS

The scores for inserted and proven lesions had the same median (8) and similar interquartile ranges (inserted, 5.5-8; real, 6.5-8). The mean scores were not significantly different between real and inserted lesions (P value = 0.17). The receiver operating characteristic curve was nearly diagonal, with an area under the curve of 0.58 ± 0.06. For the two-alternative-forced-choice study, the inserted lesions were incorrectly identified in 49% (25 out of 51) of pairs; radiologists were incorrect in 38% (3 out of 8) of pairs even when they felt very confident in identifying the inserted lesion (confidence level ≥4).

CONCLUSIONS

Radiologists could not distinguish between inserted and real lesions, thereby validating the lesion-insertion technique, which may be useful for conducting virtual clinical trials to optimize image quality and radiation dose.

Performance of 2-Dimensional Ultrasound Shear Wave Elastography in Liver Fibrosis Detection Using Magnetic Resonance Elastography as the Reference Standard: A Pilot Study

OBJECTIVES

To investigate the correlation between 2-dimensional (2D) ultrasound shear wave elastography (SWE) and magnetic resonance elastography (MRE) in liver stiffness measurement and the diagnostic performance of 2D SWE for liver fibrosis when imaging from different intercostal spaces and using MRE as the reference standard.

METHODS

Two-dimensional SWE was performed on 47 patients. One patient was excluded from the study. Each of the remaining 46 patients underwent same-day MRE for clinical purposes. The study was compliant with the Health Insurance Portability and Accountability Act and approved by the Institutional Review Board. Informed consent was obtained from each patient. Two-dimensional SWE measurements were acquired from the ninth, eighth, and seventh intercostal spaces. The correlation with MRE was calculated at each intercostal space and multiple intercostal spaces combined. The performance of 2D SWE in diagnosing liver fibrosis was evaluated by receiver operating characteristic curve analysis using MRE as the standard.

RESULTS

The 47 patients who initially underwent 2D SWE included 22 female and 25 male patients (age range, 19-77 years). The highest correlation between 2D SWE and MRE was from the eighth and seventh intercostal spaces (r = 0.68-0.76). The ranges of the areas under the receiver operating characteristic curves for separating normal or inflamed livers from fibrotic livers using MRE as the clinical reference were 0.84 to 0.92 when using the eighth and seventh intercostal spaces individually and 0.89 to 0.90 when combined.

CONCLUSIONS

The results suggest that 2D SWE and MRE are well correlated when SWE is performed at the eighth and seventh intercostal spaces. The ninth intercostal space is less reliable for diagnosing fibrosis with 2D SWE. Combining measurements from multiple intercostal spaces does not significantly improve the performance of 2D SWE for detection of fibrosis.

CT of small-bowel ischemia associated with obstruction in emergency department patients: diagnostic performance evaluation

PURPOSE

To retrospectively evaluate the diagnostic performance of computed tomography (CT) for detection of small-bowel ischemia in emergency department patients with abdominal pain and to compare the prospective interpretation with a retrospective interpretation by using surgical or pathologic findings as the reference standard.

MATERIALS AND METHODS

The HIPAA-compliant study was approved by the institutional review board, and patients consented to research authorization. Sixty patients (61 examinations) (25 male, 35 female patients; median age, 67 years; range, 0.9-89.7 years) with acute abdominal pain underwent immediate abdominal and pelvic CT and subsequent surgery of the small bowel within 7 days of CT. Prospective radiologic reports were reviewed for diagnosis of small-bowel obstruction and ischemia. Two gastrointestinal radiologists performed blinded, independent, retrospective review of the CT studies with no clinical data other than presence of acute abdominal pain. The reviewers categorized CT signs of obstruction and ischemia and estimated diagnostic certainty. Discordant findings were resolved by consensus review by a third gastrointestinal radiologist. CT interpretations were compared with prospective interpretations and surgical or pathologic findings. Sensitivity and specificity estimates with confidence intervals were calculated. Fisher exact and chi2 tests were used to assess associations between CT signs and the diagnosis of ischemia; kappa statistics were used to estimate agreement between readers.

RESULTS

In 27 (44%) of 61 CT studies, small-bowel ischemia was surgically or pathologically confirmed. Sensitivity and specificity for the diagnosis of ischemia were, respectively, 14.8% and 94.1% for prospective interpretations, 29.6% and 91.2% for reader 1, 40.7% and 85.3% for reader 2, and 51.9% and 88.2% for the consensus review. Decreased segmental enhancement was the most specific sign for small-bowel ischemia (P = .001), and its recognition would have improved the diagnostic performance of all readers. There was a significant association of the small-bowel feces sign with the presence of small-bowel ischemia (P = .046).

CONCLUSION

Diagnostic performance assessment of CT for the diagnosis of small-bowel ischemia revealed poor prospective interpretation sensitivity.

CNS metastases of carcinoma ex pleomorphic adenoma of the parotid gland

Pleomorphic adenomas (PAs), also known as benign mixed tumors, are common tumors of the parotid gland. These tumors occasionally undergo malignant transformation, with potentially devastating consequences. This case report presents the clinical and radiographic features of a rare case of biopsy proved brain and spinal cord metastases arising from carcinoma ex PA of the parotid gland.