Medications as causes of intraluminal hyperdensities: What radiologists need to know

Gallstone Ileus—Lessons from a Missed Diagnosis

Gallstone ileus is an uncommon presentation in patients with acute abdomen. Its diagnosis and treatment are often delayed due to its nonspecific clinical presentation. Presence of gallstone in ileum can be difficult to detect on computed tomography (CT) as mostly they are lucent. We report the case of a 66-year-old man with a 1-day history of vomiting and abdominal bloating. Initial CT could not identify the obstructing gall stone. On the follow-up CT, there was a distal shift of obstruction site in the intestine raising suspicion of a gallstone. We discuss the imaging findings on CT and the clues to diagnosing gallstone ileus.

CT of acute abdominopelvic hemorrhage: protocols, pearls, and pitfalls

Abdominal and pelvic hemorrhage may be secondary to a number of causes and is often a medical emergency. Patient presentation ranges from obvious trauma with evidence of hemodynamic instability to vague symptoms. CT has become the imaging modality of choice for identifying abdominopelvic hemorrhage. Recognizing acute hemorrhage as well as identifying its location and severity are key to expediting management. In the Emergency Department, ultrasound often used in the initial evaluation of trauma patients, but is not sensitive for subtle bleeds or injuries. CT is the best first-line imaging tool to identify abdominal hemorrhage and, compared with angiography, has been shown to be superior in detecting intra-abdominal bleeding, especially when the bleeding rate is low. Depending on location and etiology, abdominopelvic hemorrhage may have a characteristic appearance, such as the "sentinel clot" sign associated with blunt trauma to the solid organs or the "triangle sign" of a mesenteric bleed. The following pictorial essay reviews CT technique, study interpretation, and interpretative pearls and pitfalls in the recognition of acute abdominopelvic hemorrhage.

Dietary modifications achieved successful resolution of symptoms of gastroparesis diagnosed by demonstrating gastric food retention after overnight fasting in diabetic dialysis patients: two case reports with literature review

Background

Gastroparesis is frequently overlooked and difficult to treat. The diagnosis of gastroparesis requires standard upper gastrointestinal endoscopy to exclude gastric outlet obstruction and objective evidence demonstrating delayed gastric emptying. However, none of the internationally recommended methods for measuring gastric emptying including scintigraphy are covered by the Japanese health insurance system. Limitations in the diagnosis might be related to the disease being overlooked in Japan. Meanwhile, presence of retained food in the stomach after overnight fasting without obstruction is classically known to be suggestive of gastroparesis. Some recent reports have considered gastric food retention after an overnight fasting equivalent to delayed gastric emptying.

Case presentation

Two diabetic dialysis patients presented with nausea, vomiting, and oral feeding intolerance in the absence of mechanical obstruction. Abdominal computed tomography, upper gastrointestinal endoscopy, and ultrasonography demonstrated gastric food retention after overnight fasting. The findings led to the diagnosis of gastroparesis. Appropriate dietary modifications alone successfully relieved the symptoms despite persistent delayed gastric emptying.

Conclusions

Demonstrating retained food residue after fasting for sufficient duration might be a diagnostic alternative. Dietary modifications alone provided significant clinical benefits. Possible approaches for the diagnosis and treatment of gastroparesis in Japan should be investigated.

Intraluminal hyperdense appearance of the small bowel on high resolution computed tomography of the abdomen and pelvis secondary to use of Calcium Carbonate tablets (Tums) mimicking a small bowel fistula

Hyperdensity within the small bowel is most commonly seen with positive oral contrast agents, intraluminal hemorrhage and less likely an abnormal fistulous connection with the colon containing rectally administered contrast. We present the case of a 57-year-old female with a complex history of breast cancer and multiple abdominal surgeries presenting with intraluminal hyperdense small bowel on computed tomography (CT) performed with rectal contrast. Postsurgical CT with rectal contrast, and no oral contrast, showed multifocal regions of intraluminal hyperdensity with the small bowel anterior to and close to the surgical anastomosis. This raised concerns for a fistula between the colon and small bowel; however, surgical exploration demonstrated an intact anastomosis without a coloenteric fistula. Additional history notes that the patient consumed an increased dose of calcium carbonate tablets for a few days prior to obtaining the scan and this intraluminal hyperdense appearance of the small bowel was then attributed to this. We conclude that ingested over the counter medications can pose an imaging dilemma for radiologists as their appearance on CT could falsely mimic pathology. It is imperative to obtain a thorough clinical history in such cases to provide accurate diagnoses and decrease unwanted imaging and clinical intervention. It is also important for radiologists to be aware of the appearances of commonly consumed over the counter medications that can mimic pathology as demonstrated by this case.

Role of dual energy CT to improve diagnosis of non-traumatic abdominal vascular emergencies

Computed tomography angiography (CTA) is the modality of choice to evaluate abdominal vascular emergencies (AVE). CTA protocols are often complex and require acquisition of multiple phases to enable a variety of diagnosis such as acute bleeding, pseudoaneurysms, bowel ischemia, and dissection. With single energy CT (SECT), differentiating between calcium, coagulated blood, and contrast agents can be challenging based on their attenuation, especially when in small quantity or present as a mixture. With dual-energy CT (DECT), virtual monoenergetic (VM) and material decomposition (MD) image reconstructions enable more robust tissue characterization, improve contrast-enhancement, and reduce beam hardening artifacts. This article will demonstrate how radiologists can utilize DECT for various clinical scenarios in assessment of non-traumatic AVE.

Missed appendicitis: did unexpected intraluminal densities play a role?

A healthy 19-year-old boy presented to our emergency department with abdominal pain. His history, examination and laboratory evaluation raised concern for appendicitis. A CT study of the abdomen and pelvis was carried out by the radiologist and emergency physician and was notable only for a large amount of unexpected high-attenuation intraluminal material. With further history, this was thought to be most likely retained bismuth from over-the-counter medicine ingestion. The patient was discharged home without a diagnosis. Further review of the CT scan by a second radiologist revealed a concern for appendiceal enlargement and associated free fluid. The patient was called back for further evaluation and treatment and ultimately an appendectomy was performed. Physicians should be aware of the causes and impact of unexpected radiopaque intraluminal contents on radiological studies. Most commonly from ingested medicine, such findings can obscure mucosal details, mimic active bleeding or create a distraction from other abnormalities.