Misidentification of Medical Devices With Radiographic Contrast Functions As Retained Foreign Bodies on Postoperative Radiographs: A Report of Two Cases.

Retained foreign bodies (RFBs) during surgery are events that should be completely avoided. Herein, we report two cases where a medical device with a radiographic contrast function was mistakenly identified as RFB due to human error. Radiographs were taken for confirmation to prevent foreign body retention after surgery. Case 1 involved a 71-year-old woman who underwent a laparoscopic bilateral adnexectomy for a right ovarian tumor. Postoperative abdominal radiography revealed a 5-mm spindle-shaped shadow in the pelvic cavity. Retention of a surgical instrument was suspected; however, no abnormalities were detected in the instruments used during surgery. Based on the foreign body's location, the shadow was assumed to be a bladder catheter. After removing the catheter, a repeat radiograph was performed, and the shadow disappeared. This bladder catheter had an X-ray contrast function and was misidentified as RFB. Case 2 involved a 38-year-old woman who underwent laparoscopic resection for pedicle torsion of a right ovarian tumor. Postoperative abdominal radiography revealed a contrast thread in the abdomen. A retained surgical gauze sponge was suspected; however, the instrument count was correct. The position of the gauze sponge was checked using mobile digital radiography equipment, and the object was identified as a cotton ball with an X-ray contrast thread placed in the umbilical wound. Additionally, the appearance of the cotton ball on the radiograph was unknown, which contributed to its misidentification as RFB. Eliminating human errors, including lack of communication and unfamiliarity with medical devices, is essential to prevent the misidentification of RFBs on postoperative radiographs.