Simple and complex renal cysts in adults: Classification system for renal cystic masses.

Ultrasound and slice imaging are currently the key modalities for diagnosing simple renal cysts. Benign simple renal cysts are defined by a set of strict criteria. Any cystic lesions that do not meet these criteria should be classified as "atypical" or "complex" and considered as suspicious. For over three decades, the Bosniak classification has been the central tool for diagnosing renal cystic masses larger than 1 cm. The Bosniak classification is based upon the results of a well-established pre- and post-contrast computed tomography (CT) protocol. Lesions that are difficult to classify or that remain indeterminate after CT can benefit from a multimodal diagnostic approach combining CT, non-contrast-enhanced and contrast-enhanced ultrasound, and magnetic resonance imaging.

Renal papillary carcinoma: CT and MRI features.

PURPOSE: To describe the CT and MRI appearances of papillary renal cell carcinoma. MATERIALS AND METHODS: Retrospective study of 102 papillary carcinomas in 79 patients, 81 tumors examined by CT and 56 by MRI. Tumor size, homogeneity and contrast enhancement were recorded. RESULTS: The most common presentation of papillary renal cell carcinoma was a small homogeneous hypovascular tumor both on CT and MRI. Eighty-nine percent of lesions were hypointense on T2 weighted images compared to the renal parenchyma. Seventeen percent of the lesions did not significantly enhance with contrast on CT. All of the lesions examined on MRI had a significant enhancement percentage. Calcifications were rare and only seen in 7% of cases (CT). The second most common presentation was a bulky necrotic tumor. In addition, atypical types of disease were found which were difficult to diagnose, including infiltrating tumors and tumors with a fatty component. CONCLUSION: A homogeneous hypovascular renal tumor which is hypointense on T2 weighted images should suggest a diagnosis of papillary carcinoma. Some papillary carcinomas do not enhance significantly on CT. MRI is then required to diagnose the renal tumor.

How to characterise a solid renal mass: a new classification proposal for a simplified approach.

The reference method for characterising a solid renal mass is computed tomography. MRI and ultrasound can provide useful diagnostic information for characterising masses the cystic or solid nature of which it is not possible to determine from data from the CT scan. For characterising a solid mass, only MRI can replace the CT scan in most cases. Once a mass has been shown to be solid and vascularised and not occurring in a context suggesting an inflammatory pseudotumour, it can be put, using CT, into one of the four categories of the classification that we propose: pseudotumoral dysmorphisms (type 1); typical high-fat angiomyolipomas (type 2); suspect indeterminate tumours (type 3); typically malignant tumours (type 4).

[MR imaging of large and rare pelvic masses from non-gynecological etiology]. / IRM des masses pelviennes volumineuses et rares d'origine non gynécologique.

The diagnosis and characterization of pelvic masses may be problematic, especially when they are larger than 5 cm in diameter. The majority of large pelvic masses in women originate from gynecological structures. However, they may also originate from the GI tract, urinary tract, retroperitoneum, pelvic soft tissue structures, peritoneum and bones. MRI is the imaging modality of choice because it provides excellent contrast resolution and allows direct multiplanar imaging capabilities. Diagnosis is usually suggested after careful evaluation of the tumor location, anatomical relationships, morphology and signal characteristics. In this article, we will discuss the MR imaging features of large rare pelvic masses of non-gynecological origin, along with associated clinical and histological findings.

[CT anatomy of the normal spleen: variants and pitfalls]. / Scanographie de la rate: anatomie normale, variantes et pièges.

Normally, the spleen is located in the left hypochondrium. It is attached by the gastrosplenic and splenorenal ligaments. Its tissue composition made up of red pulp and white pulp explains the heterogenous aspect when contrast medium is injected in the arterial phase. This can make it difficult to detect intrasplenic masses. The adult spleen has no lobulations or incisures; however, the persistence of fissures separating the fetal spleen's lobules can indicate splenic lacerations in a trauma context. The ectopic spleen is a migration of the spleen from its normal anatomic location because its ligaments have not developed properly. The spleen can migrate anywhere in the abdomen or pelvis. The accessory spleen can be found in 10% of the population; it is usually located near the hilum of the main spleen or the pacreatic tail. It can be located in many other places and be confused with a mass. Polysplenia is a complex congenital syndrome associating visceral heterotaxis and concomitant bilateral left-sidedness. The spleen is divided into several splenules of the same size. Splenosis is defined by the implantation of splenic tissues in the peritoneum following traumatic rupture of the spleen.

[Renal oncocytoma: CT diagnostic criteria revisited]. / Adénome oncocytaire du rein: redéfinition des critères diagnostiques en tomodensitométrie.

PURPOSE: To redefine and evaluate the computed tomographic criteria for the diagnosis of renal oncocytoma (RO) for which renal sparing surgery should be preferred. MATERIAL AND METHOD: Retrospective study of 57 patients with 69 RO. Macroscopic and histological correlation was obtained in all cases. A double blinded comparative study was made of 60 renal tumors (containing adenocarcinomas and oncocytomas) larger than 3 cm in diameter in order to evaluate the redefined CT diagnostic criteria. RESULTS: Among RO larger than 3 cm in diameter, 55% presented a sharply defined low attenuation scar on post-contrast scans at the tubular nephrographic phase, central or eccentric, with homogeneous attenuation throughout the remainder of the hypervascular tumor which was classified in 3 different groups. The use of our CT diagnostic criteria gave a statistically significant (p < 0.05) Kappa index of inter-observer concordance of 0.71 and a specificity of 96% for the diagnosis of RO. CONCLUSION: Our redefined computed tomographic criteria for the diagnosis of renal oncocytoma, eventually associated with renal biopsy, should increase the indications for renal sparing surgery for RO larger than 3 cm in diameter.

Renal angiomyolipoma with calcification: CT-pathology correlation.

Fat containing renal tumours are usually considered as angiomyolipomas on imaging modalities. Some cases of renal cell carcinoma have been reported. Although it has been previously reported, angiomyolipomas containing calcifications are very rare. We report a case of a fatty renal tumour with calcification which was an angiomyolipoma. The calcification within the tumour was secondary to osseous metaplasia.

[Incisional subcutaneous endometrioma of the abdominal wall: report of two cases]. / Endométriose sous cutanée sur cicatrice de la paroi abdominale antérieure: à propos de deux observations.

Endometriosis occurs in up to 15% of menstruating women. Abdominal wall involvement is rare and always secondary to an invasive procedure. The authors report the imaging and clinical findings of two patients with subcutaneous endometrioma following cesarean section.

[Diagnostic imaging of peripheral renal vascular disorders]. / Imagerie diagnostique de la pathologie vasculaire rénale périphérique.

Peripheral vascular disorders of the kidney involve the intrarenal branches of the renal vascular tree. It include occlusive (infarction and cortical necrosis) and non-occlusive vascular lesions (acquired arteriovenous fistulas, arteriovenous malformation, false aneurysms and microaneurysms). Initial diagnosis relies on color Doppler US and CT angiography. Angiography plays a therapeutic role. MR imaging provides useful diagnostic information on perfusion disorders especially in patients with renal insufficiency.

[Primary retroperitoneal tumors in adults]. / Tumeurs rétropéritonéales primitives de l'adulte.

Primary retroperitoneal tumors are rare and most of the time malignant. Because of the large space in which they grow, they are often discovered lately as they are large. CT and MR are the imaging techniques of choice for the primary diagnosis and the follow up of these tumors. Multiplanar reconstructions , signal and density resolution help for the nature diagnosis. The examinations allowed to find associated signs that helps also for the right diagnosis. The purpose of this paper is to answer a serie of questions: Is the mass in the retroperitoneal space? Are they imaging signs that helps for the diagnosis of nature? Are they associated signs that helps for the diagnosis of nature? What are the most common diagnosis? Is there any place for percutaneous biopsies? What is the role of imaging in the follow up? Are there any other processes that can mimic retroperitoneal tumors?