Epiploic appendagitis is self-limited and spontaneously resolves without surgery within 5-7 days. Therefore, it is imperative for radiologists to be familiar with this entity.

CT is a highly accurate, noninvasive test for appendicitis, but the optimal CT technique is controversial. Major complications of appendicitis (perforation, abscess formation, peritonitis, bowel obstruction, septic seeding of mesenteric vessels, gangrenous appendicitis) and their management are discussed. Abdominal CT is a well-established technique in the study of acute abdominal pain and has shown high sensitivity and specificity for diagnosing and differentiating appendicitis, providing an accurate diagnosis in the early stages of disease.

ObjectiveIn this article we present a simplified algorithm-based approach to the thickening of the small and large bowel wall detected on routine computed tomography (CT) of the abdomen.BackgroundThickening of the small or large bowel wall may be caused by neoplastic, inflammatory, infectious, or ischaemic conditions. First, distinction should be made between focal and segmental or diffuse wall thickening. In cases of focal thickening further analysis of the wall symmetry and perienteric anomalies allows distinguishing between neoplasms and inflammatory conditions. In cases of segmental or diffuse thickening, the pattern of attenuation in light of clinical findings helps narrowing the differential diagnosis.ConclusionFocal bowel wall thickening may be caused by tumours or inflammatory conditions. Bowel tumours may appear as either regular and symmetric or irregular or asymmetric thickening. When fat stranding is disproportionately more severe than the degree of wall thickening, inflammatory conditions are more likely. With the exception of lymphoma, segmental or diffuse wall thickening is usually caused by benign conditions, such as ischaemic, infectious and inflammatory diseases.Key points• Thickening of the bowel wall may be focal (<5 cm) and segmental or diffuse (6-40 cm or >40 cm) in extension.• Focal, irregular and asymmetrical thickening of the bowel wall suggests a malignancy.• Perienteric fat stranding disproportionally more severe than the degree of wall thickening suggests an inflammatory condition.• Regular, symmetric and homogeneous wall thickening is more frequently due to benign conditions, but can also be caused by neoplasms such as well-differentiated adenocarcinoma and lymphoma.• Segmental or diffuse bowel wall thickening is usually caused by ischaemic, inflammatory or infectious conditions and the attenuation pattern is helpful in narrowing the differential diagnosis.

Extranodal lymphoproliferative diseases are common, and their prevalence is increasing. Non-Hodgkin lymphomas and Hodgkin disease, in particular, frequently involve extranodal structures in the abdomen and pelvis, including both the solid organs (liver, spleen, kidneys, and pancreas) and the hollow organs of the gastrointestinal tract. Because virtually any abdominopelvic tissue may be involved, many different imaging manifestations are possible, and lymphoproliferative diseases may mimic other disorders. Familiarity with the imaging manifestations that are diagnostically specific for extranodal lymphoproliferative diseases is important because imaging plays an important role in the noninvasive management of disease. However, a definitive diagnosis requires a biopsy (of bone marrow, a lymph node, or a mass), a peripheral blood analysis, and other laboratory tests. In patients with known disease, the goals of imaging are staging, evaluation of response to therapy, and identification of new or recurrent disease or of complications of therapy. In patients without known disease, imaging permits a provisional diagnosis.