[First experiments for the detection of simulated mammographic lesions: digital full field mammography with a new detector with a double plate of pure selenium]

Abstract

Purpose: The article describes an experimental phantom study of a system for digital full field mammography with a new digital detector with a double plate of pure selenium.

Materials and methods: The experiments were carried out with the new full field digital mammography system Amulet from FujiFilm. This system has a new detector (18×24 cm(2)) on the basis of highly purified amorphous selenium (a-Se) with a pixel size of 50 µm. The x-rays are converted into electric signals in the first plate which are read into the second plate with the help of an optical switch and demonstrated in the form of an image. In this way a better pixel size/volume and signal-to-noise ratio should be achieved. The object of the investigation was the Wisconsin Mammographic Random Phantom, Model 152 A (Technical Performance Mo/Mo, 28 kV, 100 mAs). Five investigators with different experiences in mammography each received three images on a monitor with different random positions of the simulated lesions in the phantom for assessment. The detection rates were compared under the same conditions with the results of two other full field digital mammography systems.

Results: The median detection rate for all images and investigators for the new doubled plated a-Se detector with optical switch was 98.7%. For both other systems with a-Si or and a-Se detectors the detection rate was 89.8% or 97.3%, respectively. There were no significant differences in the detection rate of the simulated breast lesions for all three systems considering the interobserver and intraobserver variation.

Conclusion: The first phantom study for the detection of simulated breast lesions with the new full field digital mammography system Amulet demonstrates equivalent results with the other systems used in the clinical routine. The trend towards superiority of the new system has to be confirmed in further clinical studies.