Multimodality imaging features of small bowel cancers complicating Crohn's disease: a pictorial review.

Patients with Crohn's disease (CD) are at increased risk of developing small bowel cancer, since chronic inflammation may trigger the histopathological sequence that begins from low-grade dysplasia of the intestinal epithelium and may eventually lead to malignant transformation. Owing to their location in a portion of the gastrointestinal tract which is not easily accessible to conventional endoscopic techniques, the detection of CD-related small bowel cancers is still a clinical challenge. The radiological features of CD-related small bowel adenocarcinoma (SBA) in patients with CD have been described in some previous studies, including its appearance in both CT and MRI examinations. Radiological signs of active or fibrostenotic CD may be intermixed with those suggesting the presence of CD-related SBA. In CT studies, the most relevant findings consistent with malignant transformation are the presence of a stricture with irregular asymmetric thickening of small bowel walls, loss of mural stratification, and moderate enhancement after intravenous administration of iodinated contrast media, in association with enlarged adjacent mesenteric lymph nodes. Many of the CD-related SBA features that can be observed on CT imaging are similar to those detectable by MRI. This latter modality provides the additional value of the functional characterization of small bowel strictures, thereby helping to distinguish between inflammatory, fibrotic, and malignant stenosis in the setting of active CD. Positron Emission Tomography (PET)/CT enables the metabolic assessment of enlarged mesenteric lymph nodes, and PET/MRI fusion imaging can incorporate morphological, functional and metabolic information into a single set of imaging data, thus overcoming the limitations of the separate assessment of each individual modality. Owing to the low incidence and prevalence of this long-term complication of CD, we believe that a detailed multimodality pictorial essay on this topic, also including the PET-CT and fusion imaging documentation of some cases, would be useful to the medical literature.

Real-time elastography in the assessment of liver fibrosis: a review of qualitative and semi-quantitative methods for elastogram analysis.

Despite its invasiveness, liver biopsy is still considered the gold standard for the assessment of hepatic fibrosis. Non-invasive ultrasound-based techniques are increasingly employed to assess parenchymal stiffness and the progression of chronic diffuse liver diseases. Real-time elastography is a rapidly evolving technique that can reveal the elastic properties of tissues. This review examines qualitative and semi-quantitative methods developed for analysis of real-time liver elastograms, to estimate parenchymal stiffness and, indirectly, the stage of fibrosis. Qualitative analysis is the most immediate approach for elastogram analysis, but this method increases intra- and inter-observer variability, which is seen as a major limitation of real-time elastography. Semi-quantitative methods include analysis of the histogram derived from color-coded maps, as well as calculation of the elastic ratio and fibrosis index.

US in peroneal tendon tear.

Peroneal tendon injuries are common also due to the recent increase in sports participants involved in amateur activities. Clinical evaluation generally provides a diagnosis, but diagnostic imaging is often required to confirm a clinical suspicion and make correct management decisions. Ultrasound (US) imaging is the method of choice in the study of peroneal tendon injuries due to the high resolution of the images and the possibility of performing dynamic studies. US is furthermore non-invasive and inexpensive and provides the possibility of performing US-guided steroid infiltration of the tendon sheath or the surrounding tissues. The present paper will address the normal anatomy of the peroneal tendons and related structures, US imaging techniques and the various conditions and injuries which may affect this anatomic region. Also more expensive imaging techniques, such as computed tomography and magnetic resonance imaging, will be mentioned as well as their indications; however, they are required only in rare cases in which diagnosis remains uncertain or for pre-operative assessment.

Isolated tear of the plantaris tendon: ultrasound and MRI appearance.

We report a retrospective analysis of the ultrasound and magnetic resonance imaging appearance of five patients with isolated plantaris tendon tears. Both imaging techniques allowed detection of the tear, assessment of its severity and of its location. Compared with magnetic resonance imaging, ultrasound resulted in a less expensive and time-consuming evaluation. Isolated plantaris tendon tears can clinically mimic Achilles tendon tears or thrombophlebitis. Unlike these conditions, plantaris tear has a benign outcome and does not need surgical treatment or anticoagulation.

Ultrasound of peroneal tendons.

Disorders of the peroneal tendon (PeT) complex are common and affect patients of many different ages. They can be traumatic, inflammatory, infective, or degenerative. Clinical assessment orients the diagnosis, but an imaging modality is almost always performed to confirm the clinical impression and to obtain additional information that is essential in choosing among different treatments. Due to its peculiar characteristics of high resolution, cost effectiveness, noninvasiveness, and dynamism, ultrasound (US) is now widely considered the first-line imaging modality to assess superficial tendons. US not only allows an optimal evaluation of the PeT complex but can also accurately assess its synovial sheath, retinacula, and adjacent tissues. This article describes the normal anatomy, technique of examination, and normal US anatomy of the PeT complex as well as illustrating the US appearance of its main disorders.