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 12 mm (range, 5-24 mm). 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.