New Compression Paddle for Wire Localization in Mammography

Rationale and Objectives

Current wire localization compression paddles provide a limited access window with no compression in this window. We describe a new compression paddle that addresses these issues and report on preliminary patient testing.

Materials and Methods

Four mechanical engineering students collaborated with a medical physicist, a radiographer, and two radiologists. Several concept designs were developed, one of which used a mesh surface. This went on to prototype development. After phantom testing, internal review board approval, US Food and Drug Administration waiver for nonsignificant risk device, and Medicare Part A exemption were obtained, the device was used in 10 patients going to wire localization for medical indications. Informed consent was obtained and a range of breast size was included. Wires were positioned from superior, lateral, and medial approach.

Results

A total of 10 wires were successfully positioned in nine patients. The one technical failure was due to inadequate access to the axillary region because of the single prototype size. The grid system provided accurate localization of suspicious findings. The mesh was not visible in digital mammograms so there was no interference.

Conclusion

The new paddle improves on currently available models. Advantages included lack of visual (on imaging) and technical interference from the compression mesh, and compression of the active window allowed localization of subtle findings. The large active area facilitated multiple wire placements within a single window. All localizations were easily performed on the initial image because of the large active window, obviating the need for acquisition of additional images and the associated additional radiation.

Key Words: Breast biopsy, wire localization, breast cancer, mammography