It is an X-ray technique which provides 3 dimensional image of the breast. this is a very modern technique and available at select facilities. It is an approved breast cancer screening tool by the FDA, US. A mammogram is also an X-ray of the breast but the basic difference between a digital tomosynthesis and a mammogram is that while a mammogram image is one dimensional flat image, tomosynthesis gives a two dimensional image of the breast.
Digital tomosynthesis provides a counter advantage to the drawbacks of a mammogram. Mammogram is a very good screening but with a few limitations. A mammogram is done by pulling away the breasts from the body and compressing the mass between two metal plates to take an image with whole breast view. The image x-rays are taken from two views: top to bottom and right to left (side to side). This compression can be very discomforting for some women and may deter the patient from taking a repeat test.
In mammogram the images are recorded in a film and in a digital mammogram, the images are seen on the computer. Now during mammography there is overlapping of the breasts and as such the images may hide cancerous growth in tissue underlying the top breast mass. These image are one sided images which makes it sometime difficult to assess the tumor growth.
Digital tomosynthesis takes images from various angles and multiple pictures, to cover the entire breast mass across for any abnormality. Also the pressure applied is minimal as compared to a mammogram. This pressure is primary to station the breast in a stable position during the test. The machine has an X-ray tube which moves in an arc shaped movement across the breast capturing 11 images in a duration of 7 second evaluation. Then these images from the X-ray tube are sent to the computer to be collated into a two dimensional image of the internal breast tissue. This advancement in breast cancer screening technique holds promising for the patients as well as the doctors.