Postmortem abdominal CT: assessing normal cadaveric modifications and pathological processes.

PURPOSE: To investigate the interest of postmortem non-enhanced computer tomography (CT) for abdominal lesions in a forensic context of suspicions death and to list the different radiological cadaveric modifications occurring normally at abdominal stage, which must be known by non forensic radiologists in case of any postmortem exam. MATERIALS AND METHODS: 30 cadavers have been submitted to a body CT-scan without injection of contrast material. CT exams were reviewed by two independent radiologists and radiological findings were compared with forensic autopsy data. RESULTS: False positive CT findings included physiological postmortem transudates misdiagnosed with intra-abdominal bleedings, and putrefaction gas misdiagnosed with gas embolism, aeroporty, aerobily, digestive parietal pneumatosis. Incidentalomas without any role in death process were also reported. False negative CT findings included small contusions, vascular thromboses, acute infarcts foci, non radio-opaque foreign bodies. Normal cadaveric modifications were due to livor mortis and putrefaction, and are seen quickly (some hours) after death. CONCLUSION: The non forensic radiologist should be familiar with the normal abdominal postmortem features in order to avoid misdiagnoses, and detect informative lesions which can help and guide the forensic practitioner or the clinical physician.

[Imaging of gastrointestinal stromal tumors]. / Imagerie des tumeurs stromales digestives.

Gastrointestinal stromal tumors (GIST) arising from interstitial cells of Cajal, represent the first type of solid tumor, which is very sensitive to a specific molecularly targeted tyrosine kinase receptor blocker (i. e., imatinib). On CT, which is considered as the reference technique, GISTs typically present as large, well-delineated, heterogeneous and sometimes exophytic masses. In contrast with the absence of lymph node involvement, hepatic metastasis as well as mesenteric involvement can be observed. MR-enteroclysis is indicated to investigate the local extent of the disease in specific cases whereas MR imaging is used to detect hepatic metastasis. Because of a specific treatment, contrast-enhanced imaging is needed for the follow-up of treated tumors. Evaluation of tumor response to treatment is best assessed with CT which still remains the reference imaging technique whereas FDG-PET imaging is used in specific cases.

[Linear or bubbly: a pictorial review of CT features of intestinal pneumatosis in adults]. / Linéaire ou kystique: une revue iconographique des aspects tomodensitométriques de la pneumatose intestinale de l'adulte.

Pneumatosis intestinalis is a rare condition, which is defined by the presence of gas within the bowel wall. In adult patients, pneumatosis intestinalis can be depicted in various circumstances. Owing to the routine use of CT to investigate patients with abdominal pain, pneumatosis intestinalis can be seen as an incidental finding or can be observed in association with a life-threatening disease such as bowel infarction. On CT images, pneumatosis intestinalis can display two different appearances; one that has a cystic or bubbly appearance can be considered as a chronic pneumatosis and is suggestive for a benign cause while the other, which has a linear appearance can be considered as a symptom and is more frequently secondary to a life-threatening cause. However, none of these two CT characteristics can be considered pathognomonic for any of these two categories of causes. In such situations, the analysis of the location, extent and, if any, associated findings may help to differentiate between benign and life-threatening causes. In these patients who present with abdominal signs that mimic symptoms that would warrant surgical exploration, the analysis of associated findings is critical to rule out a life-threatening cause of pneumatosis intestinalis and to obviate the need for unnecessary laparotomy. In adult patients with a known specific disease such as celiac disease, chronic pseudointestinal obstruction or other chronic diseases, even with accompanying pneumoperitoneum, pneumatosis intestinalis does not uniformly mandate surgical exploration. This pictorial review presents the more and the less common pneumatosis intestinalis CT features in adult patients, with the aim of making the reader more familiar with this potentially misleading sign.