Abstrakt

Comparison Of Technical Quality And Average Glandular Dose Between Two Tomosynthesis Mammography Equipments

Renato Caron F, Thiago Buosi, Silvia Sabino SMP, Martin Eduardo Poletti & Adhemar Longatto-Filho

Introduction : The tomosynthesis technology, DBT (Digital Breast Tomosynthesis) arises to aggregate information to the exams of mammography and even replace the two dimensions’ mammography. Quality control of these equipments are mandatory, in order to aiming the radioprotection and the optimization of the image acquisitions.

Methods : The study was prospective, controlled, with the exhibition of only simulating objects for the analysis and comparison of two tomosynthesis equipment. In the Brazilian territory, for the best of our knowledge, there are two brands of breast tomosynthesis equipments: GE equipment, SenoClaire model with nine equipment in operation in Brazil, three of them in the Pio XII Foundation in Barretos, mentioned as Equipment A; and the equipment of Hologic, model Selenia DImensions, with 14 equipment installed and in operation, named Equipment B. Image quality evaluation was performed with a dedicated simulator object for 3D exams. The images were analyzed by 4 radiologists with exams experience in DBT mode. The visualization of the images followed a routine visualization protocol, being a blind, prospective and controlled study. Both, the outcome of the assessment of the structures and the mean glandular dose that each equipment employs in 3D and 2D images, were compared and correlated.

Results : The quality control tests showed that both devices are functioning according to the recommended by international guidelines. The DGM show that for 2D tests, the equipment B presents a DGM similar to the equipment A; however, then again for thicknesses greater than 3.0cm, we started to increase to a 54% greater difference in the B equipment. Nonetheless, even with this higher value, both equipments presented results below the reference values. For 3D mode, the average difference was 24% higher for equipment B in thicknesses from 1.0 up to 6.0cm. The clinical evaluation showed that the 3D technology is superior to 2D. There was no significant differences between the two devices we analyzed, except for the DG for one of the equipment that presented a lower value.

Conclusions : Both equipments confirmed to be accomplished of representing the same amount of structures necessary to be recognized in breast cancer screening.