What’s New in Gastrointestinal Imaging – November 2021
Gastrointestinal Tract Dilatations: Why and How They Happen—A Simplified Imaging Classification. Carbo et al.
Dilatation is an enlargement of a tubular structure beyond its normal dimensions. This article and its accompanying slide show describe the mechanisms, causes and imaging patterns associated with several pathophysiologic classifications of gastrointestinal tract dilatations. The broad classifications, as outlined in the article are atony, simple obstructions, closed-loop obstructions and localized obstructions. Various pathological entities fall within each class and are elucidated in the online slide show which accompanies the article. Ultimately, imaging helps to localize the level of the obstruction or transitional point, differentiate open loop from closed-loop obstructions, estimate the severity of obstruction (partial vs. Complete) and aid in establishing a cause for the obstruction.
Can Patient Triaging with Clinical Scoring Systems Reduce CT Use in Adolescents and Young Adults Suspected of Having Appendicitis? Song et al.
This article introduces the idea of a clinical scoring system for suspected appendicitis to see which patients should receive a CT versus other clinical management. This retrospective study evaluated 2888 patients over five years with suspected appendicitis. Almost 1100 of these patients would ultimately be diagnosed with appendicitis. Prior to the study, the authors found CT for suspected appendicitis to have sensitivity of 98%, specificity of 95%, this was the target for their clinical scoring model. The article presents the different scoring systems tested and, when using the target sensitivity and specificity, found each had CT reduction rates of 0%. CT was found to be superior to all scoring systems, and the authors conclude that using clinical scoring systems to triage patients for selective CT use led to a considerable loss of diagnostic accuracy.
Foreign bodies of body orifices: A pictorial review
Bamashmos et al.
This interesting article looks at the many ways retained foreign bodies can present to an emergency department, including ingestion, inhalation, and insertion. The authors present typical clinical presentations, imaging features and management. The authors mention the age discrepancy with foreign body retention, for example stating 80% of oral ingestions happen in children up to age 3, with the most common objects being coins, toys, and button batteries. In contrast, most anorectal foreign bodies occur in men in their third to fourth decades. The article also discusses complications of insertion, which can include obstruction, ulceration, fistula formation, and perforation. Clinically, diagnosis can be challenging, especially in children and psychiatric patients due to barriers in communication, and imaging plays a key role in directing appropriate and timely management.
Imaging findings of diseases affecting the gastrohepatic ligament: not as acquiescent as it seems – Karaosmangolu et al.
This article describes the gastrohepatic ligament (GHL), one of the major portions of the lesser omentum, along with the gastroduodenal ligament. The authors state that while it may be relatively small, it can be affected by a large variety of disease processes, both neoplastic and non-neoplastic. The article begins with an overview of the anatomy and surrounding structures before discussing gastrohepatic ligament pathology. The authors give imaging characteristics of GHL abnormalities, including gastric cancer, GIST, mesenchymal neoplasms, lymphoma, metastatic disease, and infiltrating adjacent tumors such as those of hepatic origin. The authors also discuss GHL associated vascular anomalies, lymphatic anomalies, neural origin processes (I.e. neuofibromas), hematomas (I.e trauma), and infectious abnormalities.
Conventional-Dose CT Versus 2-mSv CT for Right Colonic Diverticulitis as an Alternate Diagnosis of Appendicitis: Secondary Analysis of Large Pragmatic Randomized Trial Data – Kim et al.
Right colonic diverticulitis (RCD) is an important alternative diagnosis to appendicitis as their presentation may be similar but are managed differently, as RCD is rarely treated surgically. Previous studies have shown that CT radiation dose can be reduced to as low as 2 mSv for the detection of appendicitis, however, adoption of this dose has been slow partly because of concern about missing alternative diagnoses, including RCD. This study is a post hoc retrospective analysis which uses data and images from the Korean “Low dose CT for appendicitis trial” (LOCAT). Ultimately, 400 images from patients (200 from the 2 mSv group and 200 from the conventional dose CT (CDCT) group) were selected. Roughly half of these images were from patients with a final diagnosis of RCD, while the remainder were patients with either acute appendicitis, “unspecified abdominal pain” or “other alternative diagnosis”. These images were reviewed by 4 radiologists (2 experienced radiologists and 2 residents) who were blinded to the patient selection scheme, the prospective radiology reports, patient history and the prevalence of RCD in the data set. The readers then rated the likelihood of RCD as present, absent or indeterminate. In this study, the authors found that 2 mSv CT was comparable to CDCT for the diagnosis of RCD.
References
