Pararenal pseudotumors of the diaphragm: computed tomographic features.

Two cases of diaphragmatic pseudotumors in the right posterolateral pararenal space are reported to highlight their unusual location and their confusing computed tomographic pattern.

CT features of perirectal fascia thickening after transurethral resection of prostatic adenoma.

Thickening of the perirectal fascia (PRF) has been described as a CT sign of local extension of pelvic cancers. It has been observed also after radiation therapy and various pelvic surgical procedures. To demonstrate prospectively its nonspecificity, we systematically looked for such thickening before and after consecutive uneventful transurethral prostatic resections in 17 patients presenting with benign adenomas and in one patient with an unexpected prostatic carcinoma.

[How to analyze a nuclear magnetic resonance image. Application to the study of the pelvis].

Nuclear magnetic resonance (NMR) is based on the behaviour of some atomic nuclei when they are placed in a magnetic field and subjected to radiofrequency waves of a specific length. The resonance signals they emit under such conditions are collected as localized digital data which are used to construct an image. The signals vary according to multiple tissue characteristics, notably proton density, relaxation times T1 and T2 and, where applicable, blood flow direction and velocity.

[Magnetic resonance imaging of pelvic tumors in men. Preliminary results in a series of 28 patients].

The authors conducted a retrospective evaluation of the diagnostic value of nuclear magnetic resonance in comparison with other imaging techniques in a series of 28 pelvic tumours, with the exclusion of gastrointestinal tumours. The positive diagnosis of the lesion was obtained in every case. The variation of the signal provided information concerning the tissues, while the sections in three planes, the spontaneous visibility of the vessels and the very good natural contrast related to the presence of fat which gives a high signal, facilitated staging of the tumour.

Cystic renal cancers: CT characteristics.

The preoperative distinction between renal cyst and tumor has long been a dilemma. A cystic renal adenocarcinoma may appear similar to a largely necrotic tumor or a cancer incorporated into a cyst or arising from a cyst wall. Overall, these cystic cancers present the same preoperative features.

Local recurrence after nephrectomy for primary renal cancer: computerized tomography recognition.

We diagnosed by computerized tomography 15 local recurrences in 88 patients who had undergone nephrectomy for renal cancer, with no false positives and 1 false negative. This over-all low rate (17 per cent) probably is owing to the fact that computerized tomography scans were done in patients in good clinical condition. Local recurrence was noted in 3 of 59 asymptomatic patients and in 12 of 19 patients with local symptoms.

Pseudotumoral ureteral kinking: a computed tomography pitfall.

On computed tomography, the kinking of a large ureter may falsely suggest an ureteral tumor. This pitfall likely correlates with the intraluminal protrusion of the ureteral wall folds.

Transformation of a pericardial cyst observed on long-term follow-up.

An atypical pattern of pericardial cyst was observed on a routine chest radiograph of a healthy 25-year-old woman. It appeared as an important elevation of the right diaphragm. The cystic nature of the mass was easily disclosed by ultrasonography and computed tomography, but its location--thoracic, diaphragmatic, or subphrenic--remained questionable.

Radiological evaluation of the peri- and pararenal spaces by computed tomography.

Computed tomography (CT) gives an excellent opportunity to revisit normal anatomy and to understand pathological aspects. Renal fascia alterations, on CT scans, are a sensitive sign of local lesion. While a thin renal fascia has no pathological significance, any thickening may be considered abnormal although nonspecific.

Computed tomography versus aortography in diagnosis of aortic dissection.

The use of computed tomography (CT) versus aortography is evaluated in a limited study of 17 cases of aortic dissection (AD). With the constraints of the present state of the technology and lack of availability of CT scanners at some centers, aortography remains the premier and often the only diagnostic test to choose in an emergency. CT, however, may be an asset in the diagnosis of AD when: (1) atypical or misleading clinical presentations are evident that do not require aortography; (2) aortography is contraindicated in a weakened patient, when there is no emergency; (3) aortography is a risk while there is a strong suggestion of AD; (4) patency of a false channel must be confirmed.

Computed tomography of multilocular cystic nephroma.

Three cases of multilocular cystic nephroma (MNC) tht were demonstrated by computed tomography (CT) are described. In two cases a correct preoperative diagnosis was made. In the third case, however, the mass did not fit exactly the histologic criteria for MCN.

Visibility and thickening of the renal fascia on computed tomograms.

The renal fascia can be seen on CT scans (using appropriate window settings) in most patients except those with very little fat. CT confirms current anatomical concepts; however, contrary to the illustrations shown in the literature, it clearly demonstrates that the anterior pararenal space normally exists only at the level of the retroperitoneal organs. A lesion would distend the space.