Comprendre et utiliser le CAD (Aide informatisée au diagnostic) en mammographie

[Breast cancer screening imaging: what do we do]

The purpose of this review is to evaluate the value of different breast imaging technics and their place for individual and mass screening of breast cancer according to the randomized studies on digital mammography and ultrasound screening. Analogic and numerical mammograms are validated for screening of women aged from 50 and 74 years. The additional value of ultrasound is therefore proven when the increased risk is moderate. When risk is higher (genetic or familial), MRI is the method of choice associated with conventional imaging. Individual screening is recommended before 50 for women aged from 45 and 50 and for those over 74 using the same procedures as organized screening.

[Computer-aided detection of lung nodules on thin collimation MDCT: impact on radiologists' performance]

OBJECTIVES

Evaluate the improvement in detecting lung nodules when using multidetector CT (MDCT) computer-assisted diagnosis (CAD).

MATERIAL AND METHODS

Three radiologists (R1, R2, R3) with different levels of experience independently interpreted 30 MDCT examinations of the thorax taken for screening purposes, first without and then with CAD. The diagnosis was established by two of the three radiologists interpreting the images together, assisted by the CAD.

RESULTS

The consensus reading identified 133 nodules, 61 (46%) of which were 4 mm or larger. The sensitivity values in the detection of nodules before and after using the CAD were 54% and 80% (R1), 38% and 71% (R2), and 70% and 88% (R3), respectively. When considering only the nodules that were 4 mm or larger, the sensitivity values varied before and after using the CAD, from 62% to 95% (R1), from 41% to 84% (R2), and from 74% to 92% (R3). By combining two by two the three radiologists' results obtained without the CAD, the sensitivity values were 65%, 83%, and 77%, respectively, for all the nodules, and 70%, 85%, and 77% for the nodules that were 4 mm or larger. The CAD induced a total of 105 false-positive results, with a mean of 3.5 per examination.

CONCLUSION

The lung nodules missed by the radiologist can be detected if the CAD is used as a second reader. The CAD can be at least as beneficial as the use of a second independent reader.

[Digital mammography: performance evaluation parameters and available systems in 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).