Preliminary study on the advantages of hysteroscopic myomectomy with cold knife

At present, hysteroscopic submucosal fibroids resection is mostly performed by hysteroscopic electric resection (hereinafter referred to as electric knife). During the operation, the electrothermal effect could not only damage the endometrial tissues covered by the surface of the fibroid, but also easily damage the endometrial tissues around the fibroid, which is very unfavorable for patients with fertility requirements. In addition, for some special fibroids (located at horn and fundus) or Type II and multiple submucosal fibroids, the traditional electric resection is still very difficult. With the opening of the second-child policy and the urgent desire of patients for fertility, more and more attention is paid to the concept of fertility protection in China. Therefore, hysteroscopic cold knife technology (hereinafter referred to as cold knife) has gradually entered the vision. The cold knife has the advantages of simple operation, such as little trauma and quick postoperative recovery. In this study, the advantages of cold knife in the surgical resection of submucosal fibroids are discussed by comparing the safety and effectiveness between the hysteroscopic cold knife resection (hereinafter referred to as cold knife) and the electric knife resection in the submucosal fibroids.

The clinical data of 112 patients with submucosal fibroids diagnosed and treated by hysteroscopic surgery at the Third Xiangya Hospital of Central South University from January 2017 to October 2021 were retrospectively analyzed, including preoperative general information (such as age, gravidity, abortion times, the size, location, type and number of submucosal fibroids, preoperative hemoglobin value) and intraoperative conditions [such as intraoperative bleeding, the operation time, residual rates and intraoperative complications (massive bleeding, perforation, water poisoning)]. The patients were divided into a cold knife group and an electric knife group, and there were 40 cases in the cold knife group and 72 cases in the electric knife group. The postoperative complications and the pregnancy outcomes in the 2 groups were followed up by telephone, the follow-up data included postoperative recurrence rate, pregnancy rate, pregnancy mode, and pregnancy outcome.

Compared with the electric knife group, the cold knife group had more submucous myomas located in the horn or fundus of the uterus (9.7% vs 25.0%), and more Type II myomas or combined with Type II myomas (26.4% vs 70.0%). However, there were no significant difference in intraoperative bleeding, the operation time, intraoperative complications and the residual rates between the 2 groups (all P>0.05). A total of 98 patients were followed up, including 32 patients in the cold knife group and 66 patients in the electric knife group. Compared with the electric knife group, there were lower postoperative complications in the cold knife group (12.5% vs 37.9%) (P<0.05). Among the 7 patients with multiple submucosal fibroids (the number of fibroids ≥5), there were 4 patients in the electric knife group and 3 patients in the cold knife group. In the electric knife group, the postoperative menstrual volume in the 4 patients was significantly reduced and 3 patients had postoperative fertility requirements, which were all diagnosed as intrauterine adhesion by hysteroscopy and performed further surgery. Later, 2 patients had successful pregnancy, 1 had miscarriage, and 1 had full-term spontaneous labor. However, the menstrual volume of the 3 patients in the cold knife group was not significantly reduced compared with normal menstrual volume, and 2 of them had fertility requirements, and they had natural pregnancy and full term vaginal delivery. There were no significant differences in postoperative recurrence rate, pregnancy rate, pregnancy mode and pregnancy outcome between the 2 groups (all P>0.05).

Both the electric knife and cold knife resection are safe and effective methods for the treatment of submucosal fibroids. Compared with electric knife resection, the cold knife resection has fewer postoperative complications and perhaps more advantages in endometrial protection, especially for the patients with fertility requirements, submucosal fibroids located at the fundus or horn of the uterus, Type II submucosal fibroids, and multiple submucosal fibroids.