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Local, regional lymph node involvement is an essential prognostic factor and an important determinant of treatment choices for patients with retroperitoneal and pelvic cancer. Current cross-sectional imaging modalities, including computed tomography and magnetic resonance (MR) imaging, use the nonspecific criterion of size and are limited in their ability to differentiate benign from malignant lymph nodes. MR lymphography is a promising imaging modality in differentiating benign from metastatic lymph nodes and provides information on lymph node morphology and function. Ultrasmall superparamagnetic iron oxide (USPIO) particles with a long plasma circulation time are suitable as an MR contrast agent for intravenous MR lymphography. They are taken up by macrophages in normally functioning nodes and reduce the signal intensity of tissue in which they accumulate because of T2 and susceptibility effects of iron oxide. In metastatic nodes, macrophages are replaced by cancer cells, which lack reticuloendothelial activity and cannot take up USPIO. The main mechanisms that might explain a heterogeneous node appearance after USPIO injection are discussed. In published reports, USPIO has shown high degrees of sensitivity and specificity for characterizing lymph nodes in cancer patients. We review the development of USPIO compounds, their imaging characteristics, and our clinical experience.

MRI can assess local and locoregional spread of a newly diagnosed prostate cancer by detecting extracapsular extension (ECE), seminal vesicle invasion (SVI) and lymph node invasion. Endorectal MRI remains the only accurate means to assess local extension. Pelvic MRI with surface coils and the use of superparamagnetic particules provide the sensitivity and the specificity which have never been obtained by the sole measurement of node size of the lymphatic chains draining the prostate gland. With the endorectal coil, only direct signs of extracapsular extension have been maintained and indirect signs have been discarded, giving their too low specificity. Early SVI can only be consistently detected if result of TRUS guided biopsies show involvement of the prostate base. With the pelvic phased array coil, superparamagnetic particules show that metastatic lymph nodes have a specific MR signal which can be detected in normal size nodes. Indications of imaging relies on results of parametrers available before MR imaging. More important than PSA level and Gleason score on biopsies is the so called quantitative histology, represented by the number of sextants involved by tumor and the amount of cancer (measured in mm of tumor) present on biopsies which determine a risk of extraprostatic spread. Of the risk of extraprostatic spread depends indication of MR, which is most probably unnecessary in patients at low risk (20%) of extraprostatic extension.

We report a case of subacute bowel obstruction due to a compression of the rectosigmoid junction by a chronically distended bladder, occurring in a 91-year-old male suffering from a long-standing diabetes mellitus and a prostatic adenoma. Radiographic, water-soluble contrast enema and pelvic CT features are reported.

PURPOSE: To evaluate treatment of osteoid osteoma with computed tomography (CT)-guided percutaneous excision and immediate follow-up scintigraphy. MATERIALS AND METHODS: Sixteen consecutive adolescent and adult patients underwent CT-guided percutaneous excision of a nidus with 14-gauge biopsy cutting needles, with local anesthesia. After the presence of nidus was confirmed at immediate follow-up scintigraphy, curettage of the bored cavity was performed to remove any residual fragments of the nidus. Scintigraphic and histologic findings were correlated. RESULTS: The nidus was removed successfully in 14 of the 16 patients, with no complications (mean follow-up, 15 months; range, 3-25 months). In five of the 14 patients, immediate follow-up scintigraphy showed incomplete resection of the nidus and immediate second resection was successful. Surgical resection was necessary in two of the 16 patients. CONCLUSION: CT-guided percutaneous excision with immediate follow-up scintigraphy was safe and effective for lo...

The purpose of this paper is to describe the general principle of MRI, emphasising the practical conduct of the examination which consists of three main phases. The authors define the concepts of relaxation time and T1 and T2, essential parameters for the understanding of MRI. They simply explain how to recognise a predominance of T1- or T2-weighting on MRI images. They review the principal artefacts which must be recognised in order to avoid erroneous interpretation of the images. Lastly, they define the value of MRI in clinical urology, renal pathology, especially neoplastic, and prostatic and bladder disease.

The effectiveness of renal transplantation has been considerably improved by the use of cyclosporine as an antirejection agent. However, because of those very same immunosuppressive properties, this substance may lead to several infectious or tumoral complications that raise complex therapeutic problems. This article reports about one case of immunoblastic lymphoma discovered in a patient who received renal transplantation and who had been treated with cyclosporine for two years.

The effectiveness of renal transplantation has been considerably improved by the use of cyclosporine as an antirejection agent. However, because of those very same immunosuppressive properties, this substance may lead to several infectious or tumoral complications that raise complex therapeutic problems. This article reports about one case of immunoblastic lymphoma discovered in a patient who received renal transplantation and who had been treated with cyclosporine for two years.

Among all noninvasive techniques, high-resolution ultrasonography used alone has rarely been used for the diagnosis of thrombosis in the calf. Nineteen patients with suspected AVT were examined with ultrasonography and phlebography during 4 months. For each patient, a sonogram and a phlebogram were taken within less than 24 hours and interpreted independently. The sonographic exploration with a high-resolution (5 MHz) transducer covers all deep trunks and muscular veins (soleus or gastrocnemius muscles). The positivity criterion is the persistence of a hypoechogenic endoluminal image under moderate compression. According to the phlebographic data, 65% of the patients present with thrombosis. Ultrasonography has a sensitivity of 95% and a specificity of 99% for the study of the deep trunks. Ultrasonography screens more thromboses than phlebography (23 cases versus 17). On a whole, ultrasonography seems to be more sensitive than phlebography for the diagnosis of recent sural thrombosis.

The artificial urinary sphincters are implanted to treat some urinary incontinence. Abdominal plain films allow the checking of the function of the cuff; the diameter of the pressure regulating balloon can be appreciated by ultrasound or plain film. The main complications (bending of the tubules, leak, urethral erosion, rupture of the cuff) and their radiological diagnosis are described.

The protal system of 45 normal patients have been retrospectively studied on spin echo MRI sequences (interleaved cuts): multiple artifacts have been evaluated and 24% of them were visualized at the portal system level. Thus, partial volume effect responsible for almost 25% of the artifacts is not always easily seen on a single sequence. Respiratory and aortic artifacts can deteriorate the visualization of the vascular lumen but cannot be confused with a thrombosis. Well-known artifacts, as slice entry phenomenon and even echo rephasing, represent more than 60% of the artifacts: they are readily recognized when they are typical and indicate flowing blood. On the contrary, an other artifact, representing less than 5% of the total and seen at the level of the left portal vein, simulates a thrombus, on T2 weighed images. We conclude that the frequency and polymorphism of the artifacts are limiting factors of MRI value in the diagnosis of portal vein thrombosis.

This observation illustrates the use of CT in the diagnosis of rectosigmoid hemangiomas and the assessment of their extension. The CT appearance of hemangiomas is very specific and therefore allows confirming a diagnosis that is often difficult to make with other radiological techniques and with endoscopy: phleboliths within the thickened rectal wall are a characteristic sign. CT is primarily required when radical surgery is contemplated due to disabling repeated proctorrhagia: it provides a better delineation of trans- and extraparietal hemangioma extension, knowing that adhesion (...).

The assessment of the extent of kidney cancers with MRI and CT is compared in 40 patients. The appearance of the tumor with MRI is very variable but always heterogeneous. Specific MRI features (tumoral pseudocapsule) provide a higher overall reliability (OR) than with CT for the detection of expansion beyond the capsule and into the kidney: 80% for 60%. Although the overall reliability of MRI is similar to that of CT (92% for 86%), MRI has proved its superiority for the assessment of the limits of endovenous tumoral expansion because of natural flow/thrombus contrast and of the multiple incidences of exploration. There is no significant difference between MRI (OR = 91%) and CT (OR = 88%) or the detection of lymph node involvement. Invasion of neighboring organs is better assessed with multi-incidence MRI. According to Robson's classification, the OR of MRI (77%) is not significantly higher than that of CT (65%). MRI is still a time-consuming and expensive technique, which should be reserved for cases in which iodine is contraindicated and used as a second-intention technique after CT to confirm the invasion of the capsule if partial nephrectomy is indicated, or the better delineate venous or regional invasion which CT could not assess properly.

The use of the prone position in aortography improves the visualization of the anterior wall of the aorta. This is supported by observation of an obstructed aortobifemoral by-pass and seems interesting in the study of aneurysms. More often, it is useful in case of decreased blood flow or increased local turbulence.

Since diagnostic value of double contrast colon imaging is dependent on the colon preparation used, tolerance and efficacy of 4 colon preparations were evaluated by a simple-blind, comparative, randomized study in 185 outpatients. Colon preparation involves variable combinations of 3 means: residue-free diet, laxatives and wash-out enemas. Principal criteria were evaluated under blind conditions by the same investigator during all examinations, with quantitative rating by segment (left, transverse and right colon) of adherence and colon cleanliness, and global assessment of quality of preparation. The 4 groups were comparable: mean age 44.7 years, sex ratio (male/female) 51.3%. Tolerance and compliance were elevated without significant inter-group differences. The colon preparations studied did not allow a homogeneous preparation to be obtained throughout the colon, efficacy in left colon being superior to right colon, whatever the method used. Analysis of cleanliness and adherence by segment failed to show significant differences between procedures, probably related to weak differences in their effectiveness and the strict nature of the study. The use of a global criterion tended to show value of wash-out enemas as a routine procedure, whether in outpatients or in the Radiology department.

A case of encapsulating peritonitis complicating the course of familial Mediterranean fever is reported. This encapsulating peritonitis was responsible for abdominal pain and had a "pseudocystic" appearance on ultrasonography and computed tomography. Ultrasound guided aspiration produced a yellowish fluid rich in proteins and poor in cells. Surgical operation revealed a congested appearance of the peritoneum associated with a richly fibrinous appearance of the external wall of the mass. The differential diagnosis is discussed.

The authors provide a didactic analysis of the errors in perception that can lead to false-negative findings in the detection of advanced rectocolonic cancers with double-contrast enema. They consider 5 categories of images as typical, ie. transverse or horizontal linear opacities, abnormal lumen due to haustral folds on semiaxial views, "pool sign", amputation of the cecum and irregular hypertrophy of the ileocolic valve. These mistakes will become exceptional if the double-contrast images are studied thoroughly using precise rules, and the percentage of false-negative findings in the detection of rectocolonic cancers should thus be reduced to 1%.

Twelve cases of recurrences of Hodgkin's disease on the chest wall, associated with three breast lesions and three diaphragmatic lesions, were studied by computed tomography (CT). Although the chest radiographs of all the patients were abnormal, CT was more accurate than clinical and other radiological examinations in delineating the lesions of the chest wall and in studying the extension of the relapse. Muscle enlargement was present in all cases. In seven cases osseous lesions and in seven cases pleural effusion or subpleural plaques were found. Chest wall recurrences were associated with other thoracic or abdominal lesions in 75% of the cases. Recurrences to the chest wall occur late (mean 6.3 years) in the evolution of Hodgkin's disease. They developed during the first relapse in 67% of the cases and during the second to the fourth relapse in 33% of the cases. CT is useful for the screening of lesions for which the outcome is bad. Only in four cases patients were without any evidence of disease after treatment.

Fifty four computed (CT) examinations were performed on patients with bladder carcinoma. A pathological assessment was obtained in 24 cases and the accuracy of CT in local staging was 91%. The accuracy of CT in detecting lymph nodes invasion was also 91%. Moreover, CT is helpful in the follow-up of patients under treatment. As it provides a correct pre-therapeutic evaluation in 83% cases, CT appears as an effective examination to perform in the evaluation of bladder carcinoma.

Nineteen cases of focal infectious lesions of renal parenchyma studied included 10 cases of acute focal bacterial nephritis (AFBN) and 9 of abscess, cases of pyelonephritis without radiological signs being excluded from this report. Each patient had been investigated by intravenous urography (IVU), ultrasound and CT scan imaging. Comparison of value of the different radiological explorations showed that urographic signs were inconstant and only weakly specific, the most valuable examination being CT scan imaging. The latter images show hypodense zones, clearer with contrast, of a rather triangular form and either single or multiple in AFBN, and mainly nodular images in abscess cases. Ultrasound is of intermediate value, being of high performance in cases of abscess but failing to demonstrate AFBN in about half the cases. However, it should not be totally neglected because of its case of access.

This report studies the diagnostic problem raised by benign pedunculated gastric leiomyoma identified by CT scan imaging and associated with hepatic metastases. Evaluation of the angle of attachment to the wall, the conventional feature enabling distinction between malignant and benign submucous tumours is not always a reliable indicator.