Faculty Bibliography

This study aimed to conduct a systematic literature review of small bowel adenocarcinoma (SBA) associated with small bowel Crohn's disease (CD). A systematic literature review was conducted using MEDLINE, PubMed, Embase, CINAHL, Cochrane and Google Scholar databases. Data regarding demographics, presentation, diagnosis, treatment and survival were extracted. The review included articles that reported the location of SBA in the setting of CD and excluded articles that did not state the CD location and/or cancer type. We identified 218 patients diagnosed with SBA in the setting of small bowel Crohn's disease. SBA should be in the differential diagnosis in patients with long-standing ileal CD presenting with small bowel obstruction, anaemia and perforation. SBA in the setting of CD presents diagnostic and treatment challenges; however, a high clinical index of suspicion may lead to early diagnosis and increased survival.
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PURPOSE/OBJECTIVE:For more than half of Crohn's disease patients, strictures will cause bowel obstructions that require surgery within 10 years of their initial diagnosis. This study utilizes computed tomography imaging and clinical data obtained at the initial emergency room visit to create a prediction model for progression to surgery in Crohn's disease patients with acute small bowel obstructions. METHODS:A retrospective chart review was performed for patients who presented to the emergency room with an ICD-10 diagnosis for Crohn's disease and visit diagnosis of small bowel obstruction. Two expert abdominal radiologists evaluated the CT scans for bowel wall thickness, maximal and minimal luminal diameters, length of diseased segment, passage of oral contrast, evidence of penetrating disease, bowel wall hyperenhancement or stratification, presence of a comb sign, fat hypertrophy, and small bowel feces sign. The primary outcome was progression to surgery within 6 months of presentation. The secondary outcome was time to readmission. RESULTS:Forty patients met the inclusion criteria, with 78% receiving medical treatment alone and 22% undergoing surgery within 6 months of presentation to the emergency room. Multivariable analysis produced a model with an AUC of 92% (95% CI 0.82-1.00), 78% sensitivity, and 97% specificity, using gender, body mass index, and the radiographic features of segment length, penetrating disease, and bowel wall hyperenhancement. CONCLUSIONS:The model demonstrates that routine clinical and radiographic data from an emergency room visit can predict progression to surgery, and has the potential to risk stratify patients, guide management in the acute setting, and predict readmission.

OBJECTIVE:To create a map of iodine densities within affected segments of small-bowel Crohn disease (CD) derived from contrast-enhanced dual-energy computed tomography enterography (DECTE) studies. METHODS:Twenty CD patients imaged with intravenous contrast-enhanced DECTE between June 2016 and December 2017 were retrospectively identified. Ten patients without clinical evidence of CD and 8 normal-appearing jejunal segments in CD patients were controls. Using prototype software, 8 manual contours were drawn along the mucosa of affected segments. Relatively normal-appearing bowel was included at the edges. These contours served as a basis for iodine density calculation and 3-dimensional iodine density map rendering. Color-coded iodine densities allowed detection and quantification of the most and least dense portion of each segment and also permitted relative comparison between segments. RESULTS:The average iodine density per CD involved segment ranged 1.0 to 3.3 mg/mL, which differed significantly from normal ileum (P < 0.0001) and normal-appearing jejunum in patients with CD (P = 0.0009). Standard deviations ranged from 0.8 to 1.7 mg/mL, which differed significantly from normal ileum (P = 0.0039) and normal-appearing jejunum in patients with CD (P = 0.0056). The amplitude of the power spectrum ranged from 0.66 to 3.3 demonstrating patches of iodine rather than uniform distribution. This differed significantly from normal ileum (P = 0.0005) and normal-appearing jejunum in patients with CD (P = 0.0004). CONCLUSIONS:Heterogeneous CD activity and distribution can be displayed as iodine density maps created from DECTE.

Gender-affirming surgery is becoming more accessible, and radiologists must be familiar with both terminology and anatomy following gender-affirming surgical procedures. This essay will review the most common gender-affirming genital surgeries, their post-operative anatomy, and common complications by providing intraoperative photographs, illustrations, and cross-sectional images. Routine radiologic imaging recommendations for transgender patients will also be reviewed.

OBJECTIVE:The objective of this study was to assess if bowel wall iodine density obtained from dual-source, dual-energy computed tomography enterography (DECTE) could be a biomarker of Crohn's disease activity. METHODS:Twenty-two patients with Crohn's disease imaged with DECTE from February 2016 to May 2018 were retrospectively identified by departmental report search. Iodine maps were created with commercial software (Syngovia). Iodine content was normalized to the aorta, and then manual dual-energy region-of-interest cursors were placed over the visibly assessed maximal and minimal iodine density within segments of involved as well as unaffected small bowel. The mixed Hounsfield unit value, maximum iodine density (Imax), and minimum iodine density (Imin) were recorded. The length of affected bowel demonstrating maximum disease activity as a percentage of overall involvement was subjectively assessed. A weighted iodine density (Iweighted) was calculated. The clinical assessment of disease activity using erythrocyte sedimentation rate, C-reactive protein, fecal calprotectin, colonoscopy/endoscopy, and surgery, if available, served as the reference standard. The Crohn's disease activity index was also used as a separate additional reference standard. RESULTS:Significant heterogeneity within the affected segments was present. The average Imax and Imin of affected bowel was 4.27 ± 1.11 (2.4-7.4) mg/mL and 2.71 ± 0.51 (2.2-3.9) mg/mL, respectively. Iodine density of normal-appearing small bowel was 1.40 ± 0.26 (0.9-1.9) mg/mL. The Imax and Imin of affected bowel differed significantly from normal bowel (P < 0.0001). Mixed Hounsfield unit (101.82 ± 27.5) also statistically differed (46.33 ± 19.62) (P < 0.0001). Using overall clinical assessment as the reference standard, all patients with Imin of greater than 2.6 mg/mL, Iweighted of greater than 3.3 mg/mL, or Imax of greater than 4.7 mg/mL had clinically active disease. Sixteen of 17 patients with Imin of greater than 2.2 mg/mL and 14/15 with Iweighted of greater than 3 mg/mL had clinically active disease. Using Crohn's disease activity index as the reference standard, all patients with Imin of greater than 2.7 mg/mL, Iweighted of greater than 3.6 mg/mL, or Imax of greater than 5.4 mg/mL had clinically active disease. The median effective dose was 4.64 ± 1.68 mSv (range, 2.03-8.12 mSv). CONCLUSIONS:Iodine density obtained from DECTE highlights regions of maximal activity within affected bowel segments. An iodine density of 2 mg/mL appears to be a threshold between normal bowel segments and those with active Crohn's disease. Iodine density measurement thresholds Imin of greater than 2.6 mg/mL, Iweighted of greater than 3.3 mg/mL, and Imax of greater than 4.7 mg/mL correlate with established clinical markers of disease activity, with Imin seemingly most useful in daily clinical practice.

PURPOSE/OBJECTIVE:To evaluate whole-lesion 3D-histogram apparent diffusion coefficient (ADC) metrics for assessment of pancreatic malignancy. METHODS:Forty-two pancreatic malignancies (36 pancreatic adenocarcinoma [PDAC], 6 pancreatic neuroendocrine [PanNET]) underwent abdominal magnetic resonance imaging (MRI) with diffusion-weighted imaging before endoscopic ultrasound biopsy or surgical resection. Two radiologists independently placed 3D volumes of interest to derive whole-lesion histogram ADC metrics. Mann-Whitney tests and receiver operating characteristic analyses were used to assess metrics' diagnostic performance for lesion histology, T-stage, N-stage, and grade. RESULTS:), for reader 1 a threshold <1.17 achieved sensitivity 87% and specificity 67%, and for reader 2 a threshold <1.04 achieved sensitivity 87% and specificity 83%. No metric was associated with T-stage (P > .195) or grade (P > .215). CONCLUSION/CONCLUSIONS:outperformed standard mean for lesion histology and nodal status, supporting the role of histogram analysis.

Background/Purpose : Prevalence of sacroiliitis (SI) in Crohn's disease (CD) varies widely (range 4% -39%), depending on criteria utilized to define the disease (e.g. inflammatory back pain, plain radiographs or MRI). Sacroiliitis may remain underdiagnosed in CD patients given lack of association with clinical symptoms of back pain and CD activity. However, patients with CD often undergo magnetic resonance enterography (MRE) to assess extent, severity of small bowel CD and radiographic healing, affording clinicians the opportunity to evaluate for the presence of active and/or chronic SI. We sought to identify the prevalence of sacroiliitis in CD patients utilizing MRE and determine its relationship with CD activity, especially with concurrent biologic therapy. Methods : All CD subjects undergoing MRE between years 2014-2018 at a large IBD referral center were identified. A musculoskeletal radiologist, blinded to clinical data, reviewed all MRE exams for the presence of acute bone marrow edema (BME) lesions and chronic lesions suggestive of acute and chronic SI, respectively. A second radiologist, also blinded, assessed MRE for mucosal CD activity using validated measures. Charts were reviewed for demographics, IBD characteristics, presence of back pain, clinical and endoscopic activity of CD, and Crohn's therapies within 3 months of MRE. Comparisons were made between CD subjects with and without SI using chi-square test. Univariate and multivariate logistic regression were used to determine risk factors of SI. Results : 258 subjects with CD underwent MRE during the study period with a mean age of 35 years old, 53% (n=138) were male, and mean duration of CD at the time of MRE was 9 years. Few reported back pain (8%) and 14% had previously seen a rheumatologist. Overall, 17% (n=45) of patients had MR evidence of sacroiliitis (Table 1). Female gender, presence of back pain, and later age of CD diagnosis were associated with signs of sacroiliitis (p=0.05, p< 0.001, p=0.04 respectively; Table 2). Stricturing phenotype was associated with a lower rate of SI (7% vs. 24%; p=0.018), but inflammatory or penetrating phenotypes were not. CD location, activity as noted by clinical scores, endoscopic disease activity, or radiographic disease activity on MRE, were not associated with sacroiliitis (Table 2). On multivariable analysis, back pain was associated with the presence of sacroiliitis on MRE (OR 3.0, 95% CI 1.1-5.6; p=0.04). Concurrent CD therapy with biologics did not lower the risk of sacroiliitis. Conclusion : Although often underdiagnosed, SI is a common comorbid condition in CD. While recent history of back pain was associated with the presence of sacroiliitis visualized on MRE, no correlations were found with other clinical and endoscopic markers of CD activity. Moreover, concurrent CD therapy, especially biologics, was not associated with a lower risk of sacroiliitis on MRE. With limited clinical clues and CD characteristics to suggest sacroiliitis, gastroenterologists can utilize MRE as a screening tool to detect SI and refer CD patients to rheumatologists. Presence of SI on MRE in CD patients with back pain may help identify a subset of individuals likely to benefit from switching to therapies with proven efficacy in axial SpA

BACKGROUND: Small bowel cancer (SBC) is a rare entity that can be associated with Crohn's Disease. The incidence of SBC in patients with CD is increased by 18.75-fold compared to normal population. The pathogenesis of SBC in the setting of CD is not fully understood, but the disease has a poor prognosis due to diagnostic challenges associated with the primary disease. The aim of this study is to present 2 cases treated within a year in a high volume IBD center and to conduct a systematic literature review of small bowel adenocarcinoma (SBA) associated with small bowel CD.
METHOD(S): Systematic literature review was done by using MEDLINE and EMBASE databases and data regarding demographics, presentation, diagnosis, treatment and survival were extracted. Articles that did not clearly state the location of the Crohn's disease and type of the cancer were excluded.
RESULT(S): We identified 216 patients diagnosed with small bowel adenocarcinoma in the setting of small bowel Crohn's disease from 117 studies. In this review obstruction was the most common initial symptom (n = 82, 59%; data are missing in 77 patients). Other common symptoms were abdominal pain (n = 12), anemia-bleeding (n = 11), diarrhea (n = 10), and fistulas (n = 5). there were 206 patients with one adenocarcinoma and 10 patients with 2 different adenocarcinomas. Among the patients with only one tumor, 154 patients (74.7%) were found to have ileal SBA. The median time to diagnosis of SBA from the diagnosis of CD was 18 months (1-300 months, data on 10 patients were missing). Out of 129, 64 patients (49.6%) were diagnosed with cancer after the surgical procedure whereas 46 patients (35.6%) were diagnosed intraoperatively and 15 (11.6%) were diagnosed preoperatively. Four patients (3.2%) were diagnosed at the autopsy without any surgical interventions and data were missing in 87 patients. 36.7% (18/49 patients) of the patients operated for obstruction were alive at one year, and 15.2% (7/46 patients) at 2-year. Although these percentages are lower than other studies reported in the literature, data was missing in 34 patients, so this might have affected the outcomes. CONCLUSION(S): Small bowel adenocarcinoma should be in the differential diagnosis in patients with longstanding ileal Crohn's disease presenting with small bowel obstruction, anemia, and perforation. Diagnosis and management of the small bowel adenocarcinoma in the setting of Crohn's disease is challenging and awareness and early diagnosis may avoid mortality

PURPOSE/OBJECTIVE:To compare 2D gradient-recalled echo (GRE) and 2D spin-echo (SE) echo-planar imaging (EPI) MR elastography (MRE) for measurement of hepatic stiffness in adult patients with known or suspected liver disease at 3 Tesla. MATERIALS AND METHODS/METHODS:Three hundred and eighty-seven consecutive patients underwent MRE of the liver at 3 Tesla with 2D-GRE and 2D-SE-EPI sequences. 'Mean liver stiffness (LS)' calculated by averaging 3 ROIs in the right lobe, 'Maximum LS' calculated by an ROI in the right lobe; and 'Freehand LS' calculated by an ROI in the entire liver were measured by two independent readers. Inter-observer and inter-class variability in stiffness measurements were assessed. Stiffness values were correlated with degree of liver fibrosis (METAVIR scores) in 97 patients who underwent biopsy. The diagnostic performance was compared by a receiver-operating characteristic analysis. RESULTS:indicating iron overload). There is high reproducibility for both GRE and SE-EPI variants (ICC = 0.84-0.94 for both GRE and SE-EPI MRE). The highest sensitivity, specificity, and accuracy of differentiating mild fibrosis (F0-F2) from advanced fibrosis (F3-F4) are 0.84 (GRE Freehand measurement), 0.92 (GRE Maximum stiffness measurement), and 0.88 (GRE Freehand measurement), respectively. CONCLUSIONS:High intra-class correlation and intra-reader correlation are seen on measured hepatic stiffness for both 2D-GRE and 2D-SE-EPI MRE. 2D-SE-EPI has lower failure rate. Diagnostic performance of both sequences is equivalent, with highest sensitivity for 2D-GRE Freehand stiffness measurement, and highest specificity 2D-GRE Maximum stiffness measurement.