Israel Medical Association Journal

Background: Computed tomography (CT) is the main diagnostic modality for detecting pancreatic adenocarcinoma.

Objectives: To assess the frequency of missed pancreatic adenocarcinoma on CT scans according to different CT protocols.

Methods: The medical records of consecutive pancreatic adenocarcinoma patients were retrospectively collected (12/2011–12/2015). Patients with abdominal CT scans performed up to a year prior to cancer diagnosis were included. Two radiologists registered the presence of radiological signs of missed cancers. The frequency of missed cancers was compared between portal and pancreatic/triphasic CT protocols.

Results: Overall, 180 CT scans of pancreatic adenocarcinoma patients performed prior to cancer diagnosis were retrieved; 126/180 (70.0%) were conducted using pancreatic/triphasic protocols and 54/180 (30.0%) used portal protocols. The overall frequency of missed cancers was 6/180 (3.3%) in our study population. The frequency of missed cancers was higher with the portal CT protocols compared to the pancreatic/triphasic protocols: 5/54 (9.3%) vs. 1/126 (0.8%), P = 0.01. CT signs of missed cancers included small hypodense lesions, peri-pancreatic fat stranding, and dilated pancreatic duct with a cut-off sign.

Conclusions: The frequency of missed pancreatic adenocarcinoma is higher on portal CT protocols. Physicians should consider the cancer miss rate on different CT protocols.

Background: Perivascular cuffing as the sole imaging manifestation of pancreatic ductal adenocarcinoma (PDAC) is an under-recognized entity.

Objectives: To present this rare finding and differentiate it from retroperitoneal fibrosis and vasculitis.

Methods: Patients with abdominal vasculature cuffing were retrospectively collected (January 2011 to September 2017). We evaluated vessels involved, wall thickness, length of involvement and extra-vascular manifestations.

Results: Fourteen patients with perivascular cuffing were retrieved: three with celiac and superior mesenteric artery (SMA) perivascular cuffing as the only manifestation of surgically proven PDAC, seven with abdominal vasculitis, and four with retroperitoneal fibrosis. PDAC patients exhibited perivascular cuffing of either or both celiac and SMA (3/3). Vasculitis patients showed aortitis with or without iliac or SMA cuffing (3/7) or cuffing of either or both celiac and SMA (4/7). Retroperitoneal fibrosis involved the aorta (4/4), common iliac (4/4), and renal arteries (2/4). Hydronephrosis was present in 3/4 of retroperitoneal fibrosis patients. PDAC and vasculitis demonstrated reduced wall thickness in comparison to retroperitoneal fibrosis (PDAC: 1.0 ± 0.2 cm, vasculitis: 1.2 ± 0.5 cm, retroperitoneal fibrosis: 2.4 ± 0.4 cm; P = 0.002). There was no significant difference in length of vascular involvement (PDAC: 6.3 ± 2.1 cm, vasculitis: 7.1 ± 2.6 cm, retroperitoneal fibrosis: 8.7 ± 0.5 cm).

Conclusions: Celiac and SMA perivascular cuffing can be the sole finding in PDAC and may be indistinguishable from vasculitis. This entity may differ from retroperitoneal fibrosis as it spares the aorta, iliac, and renal arteries and demonstrates thinner walls and no hydronephrosis.

Background: Acute mesenteric ischemia (AMI) is a medical condition with high levels of morbidity and mortality. However, most patients suspected of AMI will eventually have a different diagnosis. Nevertheless, these patients have a high risk for co-morbidities.

Objectives: To analyze patients with suspected AMI with an alternative final diagnosis, and to evaluate a machine learning algorithm for prognosis prediction in this population.

Methods: In a retrospective search, we retrieved patient charts of those who underwent computed tomography angiography (CTA) for suspected AMI between January 2012 and December 2015. Non-AMI patients were defined as patients with negative CTA and a final clinical diagnosis other than AMI. Correlation of past medical history, laboratory values, and mortality rates were evaluated. We evaluated gradient boosting (XGBoost) model for mortality prediction.

Results: The non-AMI group comprised 325 patients. The two most common groups of diseases included gastrointestinal (33%) and biliary-pancreatic diseases (27%). Mortality rate was 24.6% for the entire cohort. Medical history of chronic kidney disease (CKD) had higher risk for mortality (odds ratio 2.2). Laboratory studies revealed that lactate dehydrogenase (LDH) had the highest diagnostic ability for predicting mortality in the entire cohort (AUC 0.70). The gradient boosting model showed an area under the curve of 0.82 for predicting mortality.

Conclusions: Patients with suspected AMI with an alternative final diagnosis showed a 25% mortality rate. A past medical history of CKD and elevated LDH were associated with increased mortality. Non-linear machine learning algorithms can augment single variable inputs for predicting mortality.

Background: Assessment of small intestinal disease remains a challenge for both clinicians and radiologists. Modern magnetic resonance enterography (MRE) is a non-radiation modality that can demonstrate both intestinal wall pathologies and extraluminal lesions.

Objectives: To analyze the results of 213 MRE scans performed since 2005.

Methods: Consecutive MRE[1] scans performed in our academic medical center between December 2005 and November 2009 were reviewed for patients' demographic data, indications for the examination, and main imaging findings. The imaging findings recorded were mural changes and intraluminal filling defects; there were also mesenteric findings and extraintestinal inflammatory findings.

Results: During the study period 213 MRE scans were performed; 70% of them for proven or suspected Crohn's disease (CD) of the small bowel. Another indication was small bowel neoplasm (6% of the scans). Bowel wall thickening and enhancement were seen in 60% and 53% of MRE scans, respectively. Mesenteric involvement was found in 52% of the patients. Incidental extraintestinal findings were detected in 17% of the scans. In 22% of the scans there was no pathological finding.

Conclusions: Our 4-year clinical experience with MRE shows that this non-invasive and non-radiating modality is a powerful technique for evaluation and long-term follow-up of small bowel pathologies. The most common clinical indication was the evaluation of Crohn’s disease. With physicians’ increased awareness, the future use of MRE in the evaluation of other small bowel pathologies such as neoplasm and celiac disease will increase.