Development of microcalcification detection filter called “firefly” for breast ultrasound

Abstract

The morbidity and the mortality of breast cancer in Japan continue to increase year by year, making early detection very important. It is easy to detect microcalcifi cations on mammography, but they are more diffi cult to detect on breast ultrasound, which is said to be a limitation of breast ultrasound. Microcalcifi cations are found in ductal carcinoma in situ DCIS , which is the earliest stage of breast cancer. We have developed a new technology, the microcalcifi cation detection fi lter fi refl y , and examined diagnostic and clinical application. It is often diffi cult to identify the high intensity echogenic spots of microcalcifi cations on the monitor because the mammary gland has a very complicated structure on B mode ultrasound. Using the theory of CFAR Contrast False Alarm Rate , we have erased the echogenic breast tissue on screen and emphasized punctate high intensity microcalcifi cations. The micro calcifi cations can be identifi ed with this fi lter, like the glitter of fi refl ies on a dark night. Two hundred and eighteen cases were exam ined, in whom a clear increase in detectability was found. Intervention under stereo mammography guide is the mainstay of diag nosis of microcalcifi cations, but it can be performed only at a limited number of institution. The development of this fi lter will allow biopsy under guided ultrasound at any hospital, and it will also be possible to observe the microcalcifi cations on sampling. Furthermore, the extent of the surgical margin needs to be accurately evaluated before surgery. This fi lter will enable mapping of ma lignancy at the same position as the operation. Breast cancer screening with ultrasound may become widespread with use of the "fi refl y" microcalcifi cation detection fi lter. The signifi cance and utility of "fi refl y" are great.