# A Metal Detector for Clip Location Tracking of Stomach and Colon Cancer during Laparoscopic Surgery
###### Abstract
In addition, laparoscopic surgery generally causes less pain and scarring and requires a shorter hospital stay than thoracotomy or laparotomy [2]. It is difficult to detect the benign and malignant tumors in the visceral layer, cardiac orifice, pylorus, circular folds, inferior part (horizontal 3 rd), and ascending (#4 th) colon (more specifically, in the parietal peritoneum, eccum, middle circular muscle layer, pyloric zone, submuc, and serosa of the stomach and colon) through laparoscopic surgery. Thus, the prehension of mucosa incision range is difficult for tumor removal; the faulty prehension of mucosa incision range causes errors [2]. In laparoscopic surgery for tumor removal of colon and stomach cancers, the detection of tumor location using marker methods such as ink tattooing, the method using indocyanine green dye and autologous blood labeling, is extremely important. These aforementioned methods have side effects and are disadvantageous [4; 5; 6; 7; 8]. In kattooing causes the ink outflow (smudge) phenomenon within the abdominal cavity. Thus, the incision range prehension for tumor removal is difficult [4; 5]. In addition, the side effect of the ink tattooing method is the formation of peritonitis and granuloma (incarnative), and this method additionally necessitates high proficiency and is extremely expensive. The ICG fluorescein dye marking leads to intraperitoneallyally bleeding (intraperitoneal) or smudge, an iodine allergic reaction in neighboring tissue, and the ICG marking is also expensive and necessitates high proficiency [5]. In addition, ICG marking has lower visibility than the ink tattooing method. The autologous blood labeling generates hemorrhage and hepatocirrhosis, and it demands high proficiency and is expensive. Clip detection using the radio frequency identification (RFID) technique is essentially the marking of colon tumor by RFID tag [9; 10]. Some authors have suggested the development of an RFID-based system that includes a clip location determination algorithm, and the feasibility of this is demonstrated in a previous study [9]. Furthermore, this technology can detect the location of tumors in the stomach and colon simultaneously, and the time required to detect the tumor in the stomach and colon is 40.5 s and 38.4 s, respectively. The success rate of clipping (endoscopic clipping of the RFID clip) in a previous study was not high per se at 69.4% (stomach, 66.7%, n = 14/21; colon, 73.3%, n = 11/15), with the detection time and accuracy showing similar results [10]. Nonetheless, this technology detects the location of the tumor in the stomach, and the time required for detection is 25.0 s. Thus, further improvements of this developed system, including clip design, are necessary. We must overcome the dissatisfaction of medical needs. Generally, a ring-shaped permanent magnet is connected to the end of the clip using a wire. If a clip is connected around a tumor, the position of the permanent magnet connected to the clip may be different from that of the tumor due to the length of the wire. Therefore, tumor extraction may fail due to incorrect location determination [11; 12; 13; 14]. [PERSON] et al. and [PERSON] and [PERSON] proposed a technique of detection of the position of the clip on the tumor in the colon and stomach, and the time required for detection was 8.0 and 5.7 min, respectively [11; 12]. The proposal of [PERSON] et al. [13] is similar to the technology proposed by [PERSON] et al. [9] that can detect both stomach and colon tumor positions by the open-close clip closure method; the time required to detect the tumor location was found to be 24.9 s and 18.7 s, respectively. Similar to that proposed by [PERSON] et al., [PERSON] et al. [14] proposed a technology that detects the clip position of a tumor only for the colon, and the time required to detect the tumor position is 15-90 s.  
An important element of the clip-detector is a method that can speedily detect clips based on clinical experience.