[Impact of PACS implementation in a university center on radiology practice profile]. / Changements des pratiques radiologiques induites par l'implantation d'un réseau images en milieu hospitalo-universitaire.

PURPOSE: To determine the impact of a joint PACS implementation at a university medical center and cancer center on the radiology practice profile. Materials and methods. In 5 radiology sections, patients, selected based on identifiable acute or chronic diseases, underwent US, CT or MRI. Data were collected on datasheets from each provider with regards to clinical history, availability of prior examinations, description of patient management during the different phases of the examination, duration of examinations, and satisfaction. Data obtained prior to PACS implementation and 6-12 months and 30-36 months after implementation were compared. RESULTS: A total of 1098 datasheets were collected. Hard copy readings rapidly decreased. Comparison with prior examinations improved (+20.6% to 25.6%) as well as frequency of post-processing (+29%). The time required for image management was much more reduced for technologists (-75%) than for physicians (-23%). PACS implementation only temporarily improved the availability of radiology reports and the distribution of work between senior and junior radiologists. User satisfaction, initially high, progressively decreased due to saturation of the archival capabilities. CONCLUSION: PACS implementation in a large university center improves the efficiency of image acquisition but does not solve some of the inefficiencies of hospital organization.

[Digital mammography: performance evaluation parameters and available systems in France]. / La mammographie numérique: paramètres utiles à l'évaluation des systèmes et offre industrielle en France.

The purpose of this article is to review the features of digital mammography systems available in France. This article includes three parts: definition of the different components of a digital mammography system, description of different performance evaluation parameters, and review of systems currently available in France. Data from the literature as well as questionnaires from different manufacturers were used. The following vendors agreed to participate: Agfa, Fujifilm, GE Healthcare, Hologic-Lorad, IMS, Kodak, Konica Minolta, Philips, Planmed, Sectra, Siemens. For each vendor, the type of detector, type of available mammographic units and workstation, optional features (CAD), archival and printing possibilities (when vendors specifically offer dedicated solutions).

[Matching of mammary microcalcifications on images from different views]. / Mise en correspondance de microcalcifications mammaires radiographiées sous différents angles.

PURPOSE: In order to increase sensitivity and specificity in the diagnosis of breast cancer, more than one - generally two or three - mammograms of the same breast are obtained. In order to be able to carry out 3D reconstruction of microcalcification clusters on one hand, and efficiently fuse the information they carry on the other hand, one needs to match corresponding regions of microcalcifications from the different views. Unfortunately, this may be difficult at times. To help the situation, we have developed in this paper, a technique to automatically match microcalcifications found on pairs of mammograms from the same breast. MATERIALS AND METHODS: We used the computed morphological characteristics of individual microcalcifications to build a likeness function to match the microcalcifications. The geometrical constraint suitable for the system used was then applied to reduce the possibilities. From the remaining possibilities, the one with the highest likeness was selected as pair of corresponding microcalcifications. RESULTS: This technique was tested on a number of real cases and yielded 77.14% of good matches. CONCLUSION: This technique provides good results and could therefore be used either directly or for 3D-reconstruction of clustered microcalcifications.

The normal breast and its variations in mammography.

The mammographic appearance of the breast varies along the lifetime due to physiological modifications or use of hormonal therapies. Density of the glandular tissue is due to amount of cellular elements of the gland and to hydratation of the tissues. Normal variations are encountered as for example breast asymmetry. The currently breast composition should be described with the BI-RADS lexicon classification. Mammary asymmetry is frequent and has to be differentiated from pathologic changes. A good mammographic technique is mandatory for an adequate visualisation of the breast tissues.

Biliary lesions during radiofrequency ablation in liver. Study on the pig.

BACKGROUND: Radiofrequency (RF) is a method of in situ destruction of liver tumor. Biliary complications are bile ducts stenosis or biliary abcess. The aim of this work was to study consequences of liver RF on bile ducts. METHODS: A porcine model of biliary lesions was created using radiofrequency ablation liver. Twenty-two pigs were used for the study. The RF RITA 1500 generator (RITA Medical Systems, Mountain View, Calif., USA) was used for all experiments. The needle was positioned under sonographic control in liver parenchyma beside bile ducts. Two lesions were performed in left liver. Four groups of 5 pigs were treated. The pigs were sacrificed 1 or 3 weeks after the procedure. Pringle maneuver was utilized in half of the RF procedures. An ex vivo cholangiogram was obtained by direct injection into the main bile duct. Samples of RF lesions of liver parenchyma near and at a distance from the RF lesions were taken for pathological studies. RESULTS: Radiological lesions were biliary stenosis, with or without upstream bile duct dilatation, or complete interruption of the bile duct, or extravasation of the radiological contrast agent. Histological lesions of bile ducts were observed near RF lesions and at distance of the RF lesions when a Pringle maneuver was used or when the liver was removed after 3 weeks. CONCLUSIONS: RF ablation in contact of the intrahepatic bile duct induced biliary lesions. Therefore, it is required to stay away from the bile duct or to protect it when performing RF ablation.

[Breast cancers: abnormalities visible on a single view]. / Les cancers du sein: les images visibles sur une seule incidence.

This article reviews abnormal mammographic findings that do not meet the BIRADS description of masses or clusters of microcalcifications: abnormalities visible on a single view, asymmetrical densities and unusual patterns (transparent appearances, ductal patterns and diffuse abnormalities). It is important for radiologists to become familiar with unusual mammographic manifestations of malignant lesions to avoid misdiagnosis. Correlation with clinical abnormalities, optimal mammographic technique and comparison with previous films are useful and important for accurate interpretation of these difficult and/or unusual cases. Ultrasound, MRI and percutaneous biopsy are also useful in selected cases.

[Psychological adjustment of short interval follow-up mammography: about 50 cases]. / Une étude exploratoire sur le vécu psychologique des femmes lors de la surveillance des anomalies mammographiques probablement bénignes: à propos de 50 cas.

The objective was to investigate women's perceptions and the perceived stress experience when undergoing surveillance mammography for benign lesions (ACR3, BI-RADS). A semi-prospective study was carried out on women with diagnosed "probably benign" breast abnormalities. It was a multicentric study from 1st March to 10th June 2002. The survey was performed at the first follow-up mammography and included questions about perceptions and perceived stress related to the follow-up experience. The response is analysed with chi-square test. Fifty women (35-75 years) answered the questionnaire. All women were satisfied with reception. The mammographies were painful (23 cases). Subsequent time seemed to be too long (seven cases) and they were anxious in 19 cases. Quality of life was spoiled (disturbed) (20 cases). Professional and social perturbations were not frequent (four cases). Speaking to a relative is frequent (39 cases), but patients were not satisfied with it (33 cases). Medical information was estimated (47 cases) but was not satisfactory (36 cases). The median of the stress scale is 4-5. There are two pickaxes, one at 2 (11 cases), the second at 5 (8 cases). "Low-stressed" women could have an avoidance coping. "High-stressed" women could use a helplessness- hopelessness coping strategy. Women reported a good and informative medical support and adequate comprehension of the short follow-up mammography. They were reassured by the medical care, but the evaluation of the stress level shows it to be high, probably due to the uncertainty of diagnosis.

[Epithelioid renal angiomyolipoma: benign or malignant tumor?]. / L'angiomyolipome rénal épithélioïde: tumeur bénigne ou maligne?

Angiomyolipoma is a well-known rare soft tissue tumor involving the kidneys, liver and other organs. Long believed to be a benign hamartoma, angiomyolipoma is now considered a neoplasm that arises from perivascular epithelioid cell. Epithelioid angiomyolipoma is a rare variant of angiomyolipoma characterized by epithelioid cells that mimic renal cell carcinoma and is potentially malignant. Immunoreactivity with HMB45 is helpful for its identification. We report the computed tomographic and histologic findings in a 36 years old woman with epithelioid angiomyolipoma and lymph node involvement.

[Lipomatous tumors of soft tissues in the extremities and the waist in adults]. / Tumeurs graisseuses des parties molles des membres et des ceintures de l'adulte.

Lipomatous tumors of the upper and lower extremities in adults are frequent and lipoma is the most common soft tissue tumor. Most have a typical appearance at imaging but presentation and management may vary based on the exact histological subtype. The purpose of this paper is to review the main clinical, radiological and histological features of the different benign and malignant lipomatous tumors.

[Digital mammography and computer assisted diagnosis]. / La mammographie numérique: technique, applications et apport de l'aide informatisée au diagnostic.

Until recently, the film has remained the only medium of information in mammography. The film is used to record, to exploit, to store and to transmit the image. Computerization of images allows to dissociate and to optimize these different functions. Among classical factors of image quality (spatial resolution, contrast, noise), new factors should be added like the detective quantum efficiency and the conversion factor. Radioluminescent screens, then digital sensors for breast stereotactic imaging have been marketed. Manufacturers are now testing full field digital mammographs. Digital imaging allows many applications (computed-aided diagnostic, 3D imaging.) and permits the easy transfer of images for diagnosis and teaching. Three parts are presented in this chapter. The first one describes the different imaging modalities and gives a reminder of the different elements related to image quality. The second one is related to the practical aspects of full field mammography, the reading of mammograms on a review station, ergonomy in full field mammography and to possible changes for screening mammography. The third part is devoted to computed aided diagnosis and its possible application in screening.

[MR imaging findings of bone marrow reconversion induced by growth factors in 3 patients]. / Aspects IRM des reconversions médullaires sous l'effet des facteurs de croissance hématopoïétiques: à propos de 3 observations.

MRI is now the method of choice for bone marrow imaging. The MR appearance of bone marrow is influenced by the relative amounts of its fatty or hematopoietic components. In the following study, we report different patterns in changes consistent with reconversion into hematopoietic tissue of fatty marrow that were observed in 3 patients who received hematopoietic growth factors in combination with their chemotherapy for musculo-skeletal tumors of lower limbs.

[Prostate cancer]. / Cancers de la prostate.

Radiation therapy of prostate carcinoma with a curative intent implies to treat the whole prostate at high dose (at least 66 Gy). According to clinical stage, PSA level, Gleason's score, the clinical target volume may include seminal vesicles and less often pelvic lymph nodes. Microscopic extracapsular extension is found in 15 to 60% of T1-T2 operated on, specially in apex tumors. On contrary, cancers developing from the transitional zone may stay limited to the prostate even with a big volume and with a high PSA level. Zonal anatomy of the prostate identifies internal prostate, including the transitional zone (5% of the prostate in young people). External prostate includes central and peripheral zones. The inferior limit of the prostate is not lower than the inferior border of the pubic symphysis. Clinical and radiological examination: ultrasonography, nuclear magnetic resonance (NMR), CT-scan identify prognostic factors as tumor volume, capsule effraction, seminal vesicles invasion and lymph node extension. The identification of the clinical target volume is now done mainly by CT-Scan which identifies prostate and seminal vesicles. NMR could be helpful to identify more precisely prostate apex. The definition of margins around the clinical target volume has to take in account daily reproducibility and organ motion and of course the maximum tolerable dose for organs at risk.

[3D reconstruction of microcalcification clusters]. / Reconstruction 3D des foyers de microcalcifications.

PURPOSE: A characterization of the geometrical or morphological aspect of microcalcifications is not sufficient to confirm a diagnosis of cancer. On the other hand, it seems that the shape of the cluster is a pertinent and helpful criterion for diagnosis. The aim of our study is to work out a method for 3D reconstructions of clusters of microcalcifications. MATERIALS AND METHODS: After having tested different algorithms for extracting microcalcifications, we have developed a method of 3D reconstructions of the shape of the cluster from three radiographs. The technique, available using a standard mammography unit, consists of three principal steps RESULTS: The technique has been tested with two simple tridimensional phantoms and has given results with sufficient precision for possible clinical use. CONCLUSION: We plan now to apply the method in vivo with adaptation on a dedicated mammographic stereotactic unit with digital acquisition.

[CT and MR imaging of a solitary fibrous tumor of the thigh]. / Une tumeur fibreuse solitaire de la cuisse explorée par TDM et IRM.

Solitary fibrous tumor is a rare mesenchymal tumor usually involving the pleura. Extrapleural lesions may also occur. We report the CT and MRI appearance of a solitary fibrous tumor of the thigh. The imaging features as well as the histological and immunohistochemical characteristics are presented, especially its reactivity to the CD34 antigen. The tumor is most often benign, particularly in extra-pleural location, with good prognosis after total resection. Imaging is mainly useful to locate the tumor and assess its extension prior to surgery.