Objective: The purpose of this study was to report the occurrence of intraoperative loss of metallic marking clips placed during image-guided biopsy and to hypothesize the likely mechanism of this clinical problem.
Materials and methods: From January 2003 through December 2004, patients presenting for preoperative mammographic localization and operative excision of biopsy site marking clips were identified. Age, method of image-guided biopsy, number of excised specimens, and tissue diagnosis were determined. Specimen radiographs were used to identify cases of suspected intraoperative clip loss. Clips absent on specimen radiographs and postoperative mammograms were defined as lost intraoperatively. Biopsy site marking clips, surgical clips, and suction device apertures were measured.
Results: In 78 surgical procedures performed during the study period, three (3.8%) of the patients experienced clip loss. Specimen radiographs confirmed the absence of clips in all submitted tissues. A median of four (range, three to five) separate biopsy specimens were excised among these three cases. A healing biopsy site from the stereotactic biopsy preceding the clip placement procedure was confirmed in all cases. Absence of the metallic clip was confirmed on postoperative mammograms. The apertures of two types of suction device were four and two times those of the biopsy clips.
Conclusion: Intraoperative loss of metallic clips placed at the conclusion of image-guided breast biopsy is unusual but can occur during subsequent surgical excision. Repeated inability to locate the clip on specimen radiographs after accurate preoperative localization should raise the suspicion that the target clip has been lost, not missed, during surgery, likely because of inadvertent removal of the clip with the suction device.