Objective To explore the risk factors of early hypocalcemia after endoscopic thyroidectomy by breast approach(ETBA)and establish a predictive model to evaluate its occurrence risk.Methods A total of 155 patients with thyroid nodules who underwent ETBA were selected.Patients were divided into the low calcium group(＜2 mmol/L,n=41)and the normal group(≥2 mmol/L,n=114)according to the serum calcium level 24 hours after the operation.Before the operation,thyroid function and parathyroid hormone(PTH)were detected,and ultrasound was performed to evaluate cervical lymph node enlargement.Meanwhile,nodule location,maximum tumor diameter,nodule adhesion to the capsule,calcification and the edge of the nodule were also detected.The surgical conditions such as gland resection(unilateral or bilateral),operation time and misresection of parathyroid glands were recorded.PTH and serum calcium were detected 24 hours after the operation.Pathological assessment was used to evaluate benign and malignant conditions,Hashimoto's thyroiditis,multifocal lesions,thyroid capsule invasion and lymph node metastasis.Results Compared with the normal group,the cervical lymph node metastasis,malignant nodules,multifocal lesions,cervical lymph node enlargement,bilateral gland resection,parathyroid gland resection by mistake,combined Hashimoto's thyroiditis,maximum tumor diameter and operation time were increased in the hypocalcemia group,but PTH at 24 hours after the operation was decreased(P＜0.05).Multivariate Logistic regression analysis showed that cervical lymph node metastasis,long operation time,parathyroid resection by mistake,combined Hashimoto's thyroiditis and maximum tumor diameter were independent risk factors for early hypocalcemia in ETBA.Based on this,a visual nomogram model was constructed,with excellent discrimination[the area under the receiver operating characteristic(ROC)curve was 0.920(95%CI:0.834-0.971)],and the calibration curve showed that the predicted values were highly consistent with the measured values(Hosmer-Lemeshow χ2=0.007,P=0.087).Conclusion The nomogram model constructed based on multivariate Logistic regression can effectively predict the risk of early hypocalcemia after ETBA.

Objective To explore the risk factors of early hypocalcemia after endoscopic thyroidectomy by breast approach(ETBA)and establish a predictive model to evaluate its occurrence risk.Methods A total of 155 patients with thyroid nodules who underwent ETBA were selected.Patients were divided into the low calcium group(＜2 mmol/L,n=41)and the normal group(≥2 mmol/L,n=114)according to the serum calcium level 24 hours after the operation.Before the operation,thyroid function and parathyroid hormone(PTH)were detected,and ultrasound was performed to evaluate cervical lymph node enlargement.Meanwhile,nodule location,maximum tumor diameter,nodule adhesion to the capsule,calcification and the edge of the nodule were also detected.The surgical conditions such as gland resection(unilateral or bilateral),operation time and misresection of parathyroid glands were recorded.PTH and serum calcium were detected 24 hours after the operation.Pathological assessment was used to evaluate benign and malignant conditions,Hashimoto's thyroiditis,multifocal lesions,thyroid capsule invasion and lymph node metastasis.Results Compared with the normal group,the cervical lymph node metastasis,malignant nodules,multifocal lesions,cervical lymph node enlargement,bilateral gland resection,parathyroid gland resection by mistake,combined Hashimoto's thyroiditis,maximum tumor diameter and operation time were increased in the hypocalcemia group,but PTH at 24 hours after the operation was decreased(P＜0.05).Multivariate Logistic regression analysis showed that cervical lymph node metastasis,long operation time,parathyroid resection by mistake,combined Hashimoto's thyroiditis and maximum tumor diameter were independent risk factors for early hypocalcemia in ETBA.Based on this,a visual nomogram model was constructed,with excellent discrimination[the area under the receiver operating characteristic(ROC)curve was 0.920(95%CI:0.834-0.971)],and the calibration curve showed that the predicted values were highly consistent with the measured values(Hosmer-Lemeshow χ2=0.007,P=0.087).Conclusion The nomogram model constructed based on multivariate Logistic regression can effectively predict the risk of early hypocalcemia after ETBA.

Objective To verify the feasibility and safety of stomach tumor marker localization based on magnetic tracer technique in dogs.Methods Six male Beagle dogs were examined by gastroscopy.Then tracer magnets were sent to the "tumor" locations assumed in advance and fixed near the "tumors" by endoscopic soft tissue clamp.Laparoscopic gastric tumor localization was performed under general anesthesia 24 hours later.The tracer magnet was placed near the tumor on the surface of the stomach through the operating hole after the conventional establishment of laparoscope puncture parallel mirror to explore the tracer magnet.After the two magnets were attracted,the location of the tracer magnet seen under the laparoscope was the location of the gastric tumor,so as to complete the labeling and positioning of the lesion.Results All the 6 Beagle dogs were successfully implanted with tracer magnets under gastroscopy.Twenty-four hours after the gastroscopy,the pursuit magnet was successfully implanted during laparoscopic surgery.The two magnets automatically attracted each other and formed a sandwich structure of "tracer magnet-gastric wall-pursuit magnet ",which completed the location and identification of gastric tumor under the laparoscopy.Conclusion Gastroscopy combined with laparoscopy based on magnetic tracer technique is simple,accurate,safe and feasible.

Objective:To design magnets to locate colorectal neoplasms based on magnetic tracer technology, and to test its feasibility and safety by animal experiments.Methods:The magnets used for endoscopic localization of colorectal tumors consist of a tracer magnet and a pursuit magnet, both of which are ring-shaped Nd-Fe-B magnets. Eight healthy Beagle dogs were used as animal models. Tumor locations were assumed in the different parts of the colon and rectum under colonoscopy. The tracer magnet was sent to the hypothetical tumors by endoscopic soft tissue clamp and fixed near the tumors. After 24 hours, laparoscopic surgery was performed under general anesthesia. The pursuit magnet was inserted near the resected colon or rectum through the main operating hole. The tracer magnet was absorbed to the pursuit magnet to identify the location of tumors.Results:The tracer magnet and pursuit magnet were successfully designed and processed. The suction force between the tracer magnet and the pursuit magnet at zero distance was 16 N. All the 8 Beagle dogs successfully received indwelling of magnets under colonoscopy, and no magnets fell off after 24 hours. After the placement of pursuit magnet under laparoscopy, the two magnets attracted each other rapidly and accurately, and successfully completed localization of tumor site without any damage during the operation.Conclusion:Colonoscopy combined with laparoscopy for colorectal neoplasms localization based on magnetic tracer technique is simple, accurate, safe and feasible.