Retrospective case-control study to predict a potential underlying appendiceal tumor in an acute appendicitis context based on a CT-scoring system.

OBJECTIVES: To assess CT signs to discriminate an appendiceal tumor versus a non-tumoral appendix in an acute appendicitis context. METHODS: A 10-year bicentric retrospective case-control study was performed in adults. Patients with a histopathological appendiceal tumor and appendicitis were paired for age and sex with patients with non-tumorous appendicitis (1/3 ratio, respectively). Two senior radiologists blindly analyzed numerous CT findings with final consensus to perform univariate and multivariate statistical analyses. A diagnostic CT scan score was calculated with a bootstrap internal validation. Reproducibility was assessed based on the kappa statistic. RESULTS: A total of 208 patients (51 +/- 21 years; 114 males) were included (52 patients in the tumor group and 156 in the non-tumor group). In the multivariate analysis, an appendicolith and fat stranding were protective factors with OR = 0.2 (p = 0.01) and OR = 0.3 (p = 0.02), respectively, while mural calcifications (OR = 47, p = 0.0001), an appendix mass (OR = 7.1, p = 0.008), a focal asymmetric wall abnormality (OR = 4.9, p = 0, 001), or a ≥ 15 mm diameter (OR = 3.5, p = 0.009) were positive predictive factors of an underlying tumor. Using a ≥1 cut-off, our diagnostic score had an AUC = 0.87 (95 % CI, 0.82-0.93) and a positive likelihood ratio = 13.5 (95 % CI, 6.7-27.1). CONCLUSION: We developed a reliable scoring system based on CT findings, which is highly predictive of an underlying appendiceal neoplasm in an appendicitis context using a ≥1 cut-off.

Digestive diseases mimicking primary gynecological diseases or with secondary gynecological manifestations.

A wide range of gastrointestinal diseases may spread to and involve genital organs by different pathways. These pathways result in extension of the pathological process into the extraperitoneal spaces and between the extra- and intraperitoneal spaces. These communications occur either via mesenteries and ligaments or via the posterior parietal peritoneum. Thus, infectious, inflammatory or tumoral digestive diseases can extend into the pelvic organs and present with a misleading clinical picture and/or radiological features, showing the complexity of pelvic diseases in women. This article reviews, illustrates and discusses these different presentations and provides certain clues to help reach a definite diagnosis.

Imaging of mesothelioma of tunica vaginalis testis.

OBJECTIVES: To describe the imaging findings in a series of patients with mesothelioma of the tunica vaginalis testis. METHODS: We reviewed clinical data, imaging findings and follow-up information in a series of 10 pathology-proven cases of mesothelioma (all had US; 2 had MR) of the tunica vaginalis. RESULTS: A variety of patterns could be observed, the most common (5/10) being a hydrocele with parietal, solid and hypervascular vegetations; one patient had a septated hydrocele with hypervascular walls; one had multiple, solid nodules surrounded by a small, physiological quantity of fluid; one a cystic lesion with thick walls and vegetations compressing the testis; two had a solid paratesticular mass. MR showed multiple small nodules on the surface of the tunica vaginalis in one case and diffuse thickening and vegetations in the other one; lesions had low signal intensity on T2-w images and were hypervascular after contrast injection. CONCLUSIONS: A preoperative diagnosis of mesotheliomas presenting as solid paratesticular masses seems very difficult with imaging. On the contrary, the diagnosis must be considered in patients in whom a hydrocele with parietal vegetations is detected, especially if these show high vascularity. KEY POINTS: Mesotheliomas of the tunica vaginalis are rare, often challenging to diagnose preoperatively. Most common finding is a complex hydrocele with hypervascular parietal vegetations. Septated hydrocele, nodules without hydrocele, a thick-walled paratesticular cyst are less common. Preoperative diagnosis may allow aggressive surgical approach and, possibly, a better prognosis.

Radioanatomy of the retroperitoneal space.

The retroperitoneum is a space situated behind the parietal peritoneum and in front of the transversalis fascia. It contains further spaces that are separated by the fasciae, between which communication is possible with both the peritoneal cavity and the pelvis, according to the theory of interfascial spread. The perirenal space has the shape of an inverted cone and contains the kidneys, adrenal glands, and related vasculature. It is delineated by the anterior and posterior renal fasciae, which surround the ureter and allow communication towards the pelvis. At the upper right pole, the perirenal space connects to the retrohepatic space at the bare area of the liver. There is communication between these two spaces through the Kneeland channel. The anterior pararenal space contains the duodenum, pancreas, and the ascending and descending colon. There is free communication within this space, and towards the mesenteries along the vessels. The posterior pararenal space, which contains fat, communicates with the preperitoneal space at the anterior surface of the abdomen between the peritoneum and the transversalis fascia, and allows communication with the contralateral posterior pararenal space. This space follows the length of the ureter to the pelvis, which explains the communication between these areas and the length of the pelvic fasciae.

Central element in liver masses, helpful, or pitfall?

A central element was first described in focal nodular hyperplasia (FNH) as a so-called "central scar," and is normally associated with this entity. However, many other liver masses may present with a central element. Depending on its appearance, and the lesion itself, central elements can be essential, helpful, or confusing for diagnosis. Indeed, nodules that develop on liver vascular disorders, fibrolamellar hepatocellular carcinoma, large hemangioma, peripheral cholangiocarcinoma, or epithelioid hemangioenthelioma often present with a central element, thus increasing the level of diagnostic confidence when present. On the other hand, central elements are rare or atypical in liver metastases, hepatocellular adenoma, or hepatocellular carcinoma. In this setting, the presence of a central element can lead to a misdiagnosis. The description and details of the imaging features of these different central elements, especially on MRI, as well as a thorough evaluation of the entire lesion, can improve the diagnostic performance in these cases.

Appendicitis and diverticulitis of the colon: misleading forms.

Appendicitis and diverticulitis of the colon are the two main causes of febrile acute abdomen in adults. Diagnosis from imaging (ultrasound and CT) is usually easy. However, an imaging procedure which is not suitable for the clinical situation and an examination performed with the wrong protocol are sources of error and must be avoided. Anatomical variants, inflammatory cancers, complicated forms (perforation, secondary occlusion of the small intestine, peripheral abscesses, fistulae, pylephlebitis, liver abscesses) and associated signs related to a peritoneal inflammatory reaction (reflex ileus, reactive ileitis or salpingitis) can also lead to a wrong diagnosis.

Diagnosis of colonic volvulus: findings on multidetector CT with three-dimensional reconstructions.

Large bowel volvulus is a rare condition that can occur in patients who present with acute abdominal pain. Radiologists should be able to recognise its appearance on multidetector CT (MDCT) images so that the correct diagnosis can be made and catastrophic consequences can be avoided. In this article, we discuss and illustrate the MDCT and three-dimensional appearance of the various forms of large bowel volvulus. As MDCT allows the precise diagnosis of topography, mechanism and severity, this technique can provide an accurate assessment of large bowel volvulus.

[Postoperative imaging of the pancreas and duodenum]. / Imagerie post-opératoire du pancréas et du duodénum.

Pancreatic surgery is a frequent therapeutic approach for benign and malignant conditions. CT has become the imaging method of reference to detect early postoperative complications and to detect recurrent disease during long-term follow-up. Knowledge of the normal postoperative anatomy is essential for accurate interpretation of CT scans. The purpose of this paper is to illustrate the normal and abnormal CT appearances of common surgical procedures involving the pancreas.

[Imaging of a thickened-wall gallbladder]. / Imagerie des épaississements de la paroi vésiculaire.

Thickening of the gallbladder wall may result from a large spectrum of pathological conditions, intrinsic as well as extrinsic to the biliary tract, and may have different appearances. Accurate diagnosis is usually established after a correlation of imaging findings, laboratory data and clinical history. US remains the initial imaging modality for the evaluation of acute right upper quadrant pain. CT and MRI are complementary to US and have an increasing role in assessing a thickened-wall gallbladder.

[Torsion of an epiploic appendage inside a Spigelian hernia: a first imaging case report]. / Torsion d'un appendice épiploïque au sein d'une hernie de Spigel: premier cas rapporté en imagerie.

We present the first case illustred in imaging of an epiploic appendage torsion inside a Spigelian hernia.

[Imaging of pancreatic adenocarcinoma]. / Imagerie de l'adénocarcinome du pancréas.

Pancreatic cancer remains the fourth most common cause of cancer death. Surgery remains the only option for cure. Accurate diagnosis and staging are essential for appropriate management of patients with pancreatic cancer. This paper reviews the state of the art for imaging modalities in the diagnosis and staging of pancreatic adenocarcinoma. The crucial role of CT has increased with the new generation of multidetector CT.