Radionuclide small intestine imaging

Small Bowel Imaging: Computed Tomography Enterography, Magnetic Resonance Enterography, Angiography, and Nuclear Medicine

Radiology examinations play a major role in the diagnosis, management, and surveillance of small bowel diseases and are complementary to endoscopic techniques. Computed tomography enterography and magnetic resonance enterography are the cross-sectional imaging studies of choice for many small bowel diseases. Angiography still plays an important role for catheter-directed therapies. With the emergence of hybrid imaging techniques, radionuclide imaging has shown promise for the evaluation of small bowel bleeding and Crohn disease and may play a larger role in the future. This article reviews recent advances in technology, diagnosis, and therapeutic options for selected small bowel disorders.

Enteroscopy and radiology for the management of celiac disease complications: Time for a pragmatic roadmap

Celiac disease is the most common autoimmune enteropathy in Western countries, and is usually associated with a good response to the gluten free diet and an excellent prognosis. However, a minority of patients develop complications of the disease, such as refractory celiac disease, ulcerative jejunoileitis and neoplastic complications such as adenocarcinoma of the small bowel and enteropathy associated T cell lymphoma. Neoplastic complications described in association with celiac disease have a high mortality rate, due to their aggressive behavior and to the usual advanced stage at the time of diagnosis. In recent years, the detection of small bowel lesions has dramatically improved thank to the availability of highly performing radiologic and endoscopic techniques. The diagnostic delay of malignant complications in patients with celiac disease may be improved by establishing a pragmatic flowchart for the identification and follow up of "at risk" patients. We performed a comprehensive review of the articles published on this issue in order to promote a roadmap to be applied when facing with celiac patients with suspected small bowel complications.

Imaging the small bowel

PURPOSE OF REVIEW

Radiologic investigations continue to play a pivotal role in the diagnosis of pathologic conditions of the small intestine despite enhancement of capsule endoscopy and double-balloon endoscopy. Imaging techniques continue to evolve and new techniques in MRI in particular, are being developed.

RECENT FINDINGS

Continued advances in computed tomography (CT) and MRI techniques have reinforced the importance of these imaging modalities in small bowel assessment. The more invasive enteroclysis technique yields better small bowel distension for both CT and MRI when compared with peroral enterography, but no clinically significant difference is seen in terms of diagnostic accuracy. Recent concern regarding radiation exposure means that MRI is gaining in popularity. Fluoroscopic studies such as barium follow through and small bowel enteroclysis are being replaced by the cross-sectional alternatives. Contrast-enhanced ultrasound is showing results comparable with CT and MRI, but concern remains regarding reproducibility, especially outside centres that specialize in advanced sonographic techniques.

SUMMARY

CT and MRI enterography are comparable first-line modalities for patients with suspected small bowel disease, but magnetic resonance enterography is favoured given the absence of ionizing radiation. Capsule endoscopy is a reasonable alternative investigation in exploration of chronic gastrointestinal blood loss, but is best kept as a second-line test in patients with other symptoms.