[ROC analysis of image quality in digital luminescence radiography in comparison with current film-screen systems in mammography].

AIM

To compare in mammography the image quality of digital luminescence radiography (DLR) to that of usual film screen mammography and xeromammography.

MATERIALS AND METHODS

Three single emulsion film-screen combinations, one double coated high resolution film and xeroradiography, were tested for this purpose. In our phantom study the detectability of microcalcifications, fibrils and low contrast details were first of all studied separately. Image processing techniques were, for example, contrast variation by grey scale level windowing, "unsharp mask" filtering and regulatable edge enhancement. Phantom images were made and then the image quality was evaluated by observer performance study using a receiver operating characteristic (ROC analysis).

RESULTS

Best results in respect of detection of microcalcifications and fibrils were found in xeroradiography, luminescent image plate and double-coated film-screen combination. These systems showed more favourable ROC curves than the single emulsion film-screen combinations.

CONCLUSIONS

Our results indicate that image quality of digital images in the field of image processing is equal to that of conventional mammographic techniques and partially superior to detection of low contrast details.