Preoperative and Intraoperative Sonographic Visibility of Collagen-Based Breast Biopsy Marker Clips

Rationale and Objectives

The aim of this study was to determine the sonographic visibility of implanted collagen-based breast biopsy marker clips in the clinic and operating room.

Materials and Methods

Female patients aged ≥18 years who presented for preoperative surgical evaluation within 4 weeks of ultrasound-guided breast biopsy and collagen-based marker clip placement were eligible for this pilot study. The sonographic visibility of the marker clips was rated from 1 (not visible) to 5 (clearly visible) by surgeons at the preoperative appointment, by radiologists at wire localization, and by surgeons in the operating room. Visibility was considered inadequate for values of 1 or 2 and adequate for values of 3, 4, or 5. The data were compared using Wilcoxon's signed-rank test for paired differences across physician (radiologist vs surgeon), time (preoperative visit vs day of surgery), and target (lesion vs clip).

Results

Twenty-five patients with 26 lesions were enrolled, and 19 patients returned for all imaging procedures. The mean lesion size was 12mm (range, 5–24mm). Adequate marker clip visibility assessed by the surgeons decreased from 80% (20 of 25) at the preoperative appointment to 65% (11 of 17) in the operating room, but the difference was not significant (P=.27). Visibilities of the lesions and clips were similar at the preoperative appointment (P=.61), but the clips were significantly less visible on the day of operation (P=.03).

Conclusion

The sonographic visibility of collagen-based marker clips is variable and likely decreases over time but may be adequate to guide intraoperative surgical excision in many cases.

Key Words: Breast cancer, ultrasound, biopsy marker clips, wire localization