ABSTRACT
Objective:To explore the clinical application value of preoperative colonoscopic marking by Nd-Fe-B magnet ring to assist laparoscopy.Methods:A total of 51 patients with colorectal tumor who underwent radical laparoscopy from January 2020 to October 2021 at the Department of Gastrointestinal Surgery, Guizhou Provincial People's Hospital were recruited. The patients were marked by Nd-Fe-B magnet ring under endoscopy one day before the operation, another magnet ring was sent into the abdominal cavity during the radical laparoscopy through cannula. The two magnet rings were attracted and clung to each other to orient the lesions. The basic information of patients, location of preoperative marks under endoscopy and laparoscopy conditions were recorded.Results:All 51 Nd-Fe-B magnet rings were successfully located to the position of colorectal tumor and fixed. According to the location of the lesions, there were 15 cases of transverse colon, 12 cases of descending colon, 19 cases of sigmoid colon, and 5 cases of upper rectal segment. According to the lesion type, there were 21 cases of colon cancer, 25 cases of polyp carcinomatosis, and 5 cases of laterally spreading tumors with partial carcinomatosis. There were 5 cases with positive margins after endoscopic mucosal resection and 1 case with positive margin after endoscopic submucosal dissection. All lesions were accurately located during the operation. The marking time was 4.1±1.2 min (3-6 min) before the operation and the localization time was 1.5±1.1 min (0.9-5.3 min) during the operation. All magnet rings were removed from the body by laparoscope. The mean distances between the tumor and the cutting edge of the proximal and distal intestinal segments were 5.5 cm and 6.3 cm, respectively. No complications such as colon mucosal injury, bleeding, intestinal perforation or local inflammatory reactions occurred.Conclusion:Nd-Fe-B magnet ring tracer technique for laparoscopic orientation is simple, fast, accurate and safe with no need for additional equipment or apparatus, which is worthy of clinical application.
ABSTRACT
more efficient tooth movement. The purpose of this study was to evaluate the effect of different static magnetic fields of ND-Fe-B magnet on MC3T3-E1 cells by measuring the alkaline phosphatase activity and observing the amount of stained alkaline phosphatase. For measuring of alkaline phosphatase activity, MC3T3-E1 cells were seeded in first and third row of 12 well culture plate. And Nd-Fe-B magnets were positioned under the first column of first and third row to apply different static magnetic fields(first column:100mT ; second column:4.6mT ; third column:0.5mT ; forth column:0.0mT) to the cells for 7, 13, 19, and 25 days. For staining of alkaline phosphatase, MC3T3-E1 cells were seeded in 100mm culture plates. And Nd-Fe-B magnets were positioned under the corner of plates to apply different static magnetic fields(magnet side:100mT ; the opposite side:0.5mT) to the cells for 7, 13, 19 and 25 days. The results were as follows : 1. ALP activity was increased until day 19 in biochemical determination as well as in histochemical staining. 2. The application of higher magnetic field(100mT) suppressed ALP activity at day 13, 19, 25. On the contrary, the application of the lower magnetic field(4.6mT, 0.5mT) significantly enhanced the ALP activity. 3. Consistent with enzyme assay, histochemical staining of ALP also demonstrated that higher magnetic field(100mT) suppressed ALP activity, lower one(0.5mT) enhanced.