Vaginal natural orifice transluminal endoscopic surgery (vNOTES) in myomectomy: a novel minimally invasive technique review.

First, for patients scheduled to undergo vNOTES myomectomy, iodophor vaginal scrubbing is conducted twice a day. Prophylactic antibiotics, commonly intravenous prophylaxis with 2 g of cefazolin or 0.9 g of clindamycin, are recommended half an hour before the procedure [ 18 ]. Preoperative bowel preparation generally involves an enema. However, patients with posterior uterine myoma do not need to undergo intestinal preparation. The patients receive general anesthesia with muscular relaxation and endotracheal intubation. Then, a Foley catheter is indwelled. The patients are positioned in the Trendelenburg position combined with the lithotomy position or the prone position. When in the prone position, a team of 2–4 additional nurses facilitate an 180-degree rotation of the patient, while an anesthesiologist turns the head to one side to ensure the endotracheal tube remains unobstructed [ 17 ]. It should be noted that it is critical to place a gel pad on the operating table to reduce abdominal pressure before fixing the position [ 16 ]. The skin of the vagina and perineal area is disinfected with iodophors. In addition, the assistant generally sits on the surgeon’s left side, unless otherwise decided by the surgeon in exceptional case (Fig. 1 ). Fig. 1 This depicts the lateral view and top view of the prone position This depicts the lateral view and top view of the prone position The surgical equipment required for vNOTES myomectomy is listed in Table 1 . Table 1 The surgical equipment required for vNOTES myomectomy Preoperative instruments A gel pad (for the prone position) Vaginal surgical instruments • Vaginal retractor × 2 (long and short) • Cervical claws • Tissue scissors • Forceps × 2 (traumatic and atraumatic) • Long needle holder • Cold blade long handled scalpel • Laparoscopic puncture needle (standby) • Specimen bag Conventional laparoscopic instruments • A 10-mm 30° rigid laparoscope • Laparoscopic unipolar hook • Laparoscopic bipolar device • Endoscopic scissors • Endoscopic graspers • Toothed endoscopic graspers • Suction device Specific for vNOTES • vNOTES-port Sutures • 0# absorbable barbed suture • 2–0 absorbable suture The surgical equipment required for vNOTES myomectomy • Vaginal retractor × 2 (long and short) • Cervical claws • Tissue scissors • Forceps × 2 (traumatic and atraumatic) • Long needle holder • Cold blade long handled scalpel • Laparoscopic puncture needle (standby) • Specimen bag • A 10-mm 30° rigid laparoscope • Laparoscopic unipolar hook • Laparoscopic bipolar device • Endoscopic scissors • Endoscopic graspers • Toothed endoscopic graspers • Suction device • 0# absorbable barbed suture • 2–0 absorbable suture For anterior uterine leiomyoma, the anterior vagina wall is exposed using a short vaginal retractor while clamps draw the cervix downward. Once the vesicouterine peritoneal fold is clearly visualized, scissors are used to incise the tissue. During dissection, a wet gauze is used for blunt dissection as close to the cervix as possible, with the incision length approximately 2 cm. For posterior uterine leiomyoma, pull the posterior of cervix up and put the long retractor to expose the Douglas pouch. After that, tissue scissors are used for opening the fornix. The length of incision is also 2 cm. To reduce the incidence of adjacent organ injury, it is recommended that the incision be made with a minimum distance of 1 cm from the cervix, and the dissection process should proceed in the direction toward the uterus [ 19 , 20 ]. If you are not sure for steps of opening fornix, you can use a puncture needle with inflation to assess whether entering the abdominal cavity. Never perform a violent action to damage the adjacent organs, such as bladder and bowel. If the adjacent organs, such as intestines and bladder, are accidentally damaged, it is not essential to convert to the trans-abdominal approach [ 20 ]. Surgeons can also continue to repair the injury via vNOTES approach when safety can be ensured [ 14 , 20 ]. However, in the event of life-threatening vascular trauma or other situations rendering repair unfeasible, immediate conversion to trans-abdominal surgery and subsequent repair is imperative. First, insert a disposable multi-instrument access port into the pelvic cavity via the incision. Subsequently, establish a pneumoperitoneum by insufflating CO 2 to a pressure of 14 mmHg. Next, position the patients in the Trendelenburg position, which makes the bowel away from the surgical field. Our institution typically utilizes the port manufactured by Beijing Aerospace Kadi Technology Development Institute, arranging the four trocars in a rhombus shape. In cases where medical resources are restricted, a self-constructed glove-port can serve as an alternative [ 21 ]. First, a 30°10-mm rigid laparoscope was inserted into the abdomino-pelvic cavity for exploration (Fig. 2 ). Once the position of the myoma was identified, the 6 units of pituitrin were injected into the junction of the myometrium and the fibroid. Then, a unipolar hook or ultrasonic knife incised the protruding envelope (Fig. 3 ). Myoma enucleation was conducted following the same protocol as conventional laparoscopy [ 22 ]. After the enucleation was completed, the fibroid was placed into a specimen bag to avoid intra-abdominal spillage during hand-morcellation. Finally, the uterine defect was closed in double layers using 0# absorbable barbed suture. Fig. 2 Pelvic cavity exploration in prone position. A This image shows the left pelvic anatomy of a prone patient, including the anatomical relationships between posterior myoma, left ureter and intestine. B This image shows the right pelvic anatomy of a prone patient, including posterior myoma, left ureter and intestine Fig. 3 Enucleation of the posterior uterine myoma Pelvic cavity exploration in prone position. A This image shows the left pelvic anatomy of a prone patient, including the anatomical relationships between posterior myoma, left ureter and intestine. B This image shows the right pelvic anatomy of a prone patient, including posterior myoma, left ureter and intestine Enucleation of the posterior uterine myoma Before releasing the pneumoperitoneum and removing the cap of port, the specimen bag was pulled down to the fornix preventing it from falling into the abdominal cavity. Due to the flexible ring of Gel port and the elastic vaginal wall, the small size myoma could be easily removed. For large size fibroid, the “apple-cutting” method was used to reduce the bulk until the specimen was extracted. During the removal process, the first assistant was required to expose the visual field to avoid scratching the vaginal wall and nearby organs. The pneumoperitoneum was built once again. After confirming that there was no active bleeding at the surgical interface, the blood is drained thoroughly. The vaginal retractors were used to expose the anterior or posterior wall. A cervical claw was applied to clamp the cervix at 12 or 6 o’clock, and then four ALIS clips were used to clamp the incision, with 2 clips at the lateral sides and 2 clips at the midpoints. The vaginal incision was closed with 2–0 absorbable suture in a double continuous locked pattern. Finally, the suture was tied off and cut. Neither gauze nor the drainage tube was placed routinely. Antibiotics should be continued for 48 h postoperatively to prevent infection [ 12 , 20 ]. Sexual intercourse and tub bathing are prohibited for 4–6 weeks postoperatively. A follow-up visit at the outpatient clinic and an ultrasound examination of the pelvic cavity should be completed 1 month after operation.

vNOTES has been proven to be a feasible and effective approach in myomectomy. This review outlines the standard surgical steps, aiming to facilitate its integration into routine clinical practice, especially for patients seeking faster recovery and superior cosmetic outcomes. However, several challenges need to be addressed, including infection prevention protocols, surgical conversion and the technical application difficulties. Further randomized controlled studies and specialized technical training are needed to address these obstacles and assess long-term outcomes. Such research and training will not only help refine the vNOTES technique but also deepen our understanding of its potential, ultimately ensuring better patient care and facilitating the wider adoption of this innovative surgical approach in myomectomy procedures.

Myomectomy pose challenges in terms of the vaginal approach. Nevertheless, vNOTES technique facilitates exploration of deeper anatomical areas and visualizes intra-abdominal structures better [ 23 ]. In 2014, Lee et al. reported the first case series of 3 vNOTES procedures for vNOTES myomectomy [ 24 ]. However, medical researchers rarely carried out the vNOTES myomectomy since its challenge of suture and restricted operative space. The good news is that it has become a conventional surgical approach with the improvement of surgical design, especially for women with single uterine fibroid [ 25 ]. There has been an increasing number of studies focusing on vNOTES myomectomy, including 5 case reports [ 26 – 30 ], 2 case series [ 24 , 26 ], 2 prospective cohort studies [ 25 , 31 ], 2 retrospective cohort studies [ 14 , 16 ], 1 prospective comparative study [ 32 ], and 3 retrospective comparative studies[ 9 , 17 , 33 ]. Among these studies, vNOTES myomectomy has been considered a feasible and safe approach, even for uterine malformation and special fibroid location [ 28 , 29 ]. vNOTES myomectomy significantly leads to intraoperative outcomes that are not inferior to those of other surgical approaches. This advantage in terms of safe and fast specimen removal is primarily attributed to the vaginal wall, which is more elastic than the abdominal tissue [ 27 , 34 ]. Meanwhile, this approach allows surgeons to avoid prolonged standing positions and reduces their fatigue during the procedure [ 9 ]. Clinical researches revealed that the vNOTES approach was not associated with intraoperative bleeding (P>0.05) [ 9 , 32 , 33 ]. Regarding surgical duration, studies demonstrated no statistically significant difference between LESS and vNOTES (P>0.05) [ 9 , 32 , 33 ]. In terms of postoperative outcome, vNOTES myomectomy was associated with attributed to a shorter hospital stay, earlier time to exhaust and a lower rate of pain medication use (P<0.05) [ 9 , 32 , 33 ]. The reason for above-mentioned better surgical outcomes could be as follows. First, vNOTES approach was mainly performed in the pelvic cavity, causing less impact on the upper abdominal organs. Second, intestines are pushed upward closely to the abdominal cavity to minimize mechanical irritation during the surgery. Third, to avoid affecting the surgical field of view, the blood was immediately suctioned, thereby reducing the chemical stimulation from fluid and release of inflammatory factors. Finally, the vNOTES incision is made at the anterior/posterior fornix, which is less sensitive to pain due to visceral nerves, allowing patients to get earlier activities [ 33 ]. This promotes gastrointestinal peristalsis, accelerates postoperative recovery, and shortens the hospital stay [ 33 ]. Nine articles (n = 282) reported the maximum diameter of myomas [ 9 , 24 – 26 , 28 – 30 , 32 , 33 ]. The mean diameter was 6.9 cm (3.0–10.8 cm), and the maximum diameter of myomas reported so far is 10.8 cm. In addition, data revealed that for each 1 cm in tumor size, the duration of surgery was significantly prolonged (p = 0.01) [ 9 , 33 ]. In addition, tumor size was significantly associated with operative bleeding (P500 ml in the vNOTES group were associated with myoma diameter exceeding 8 cm [ 33 ]. However, none of the patients were converted to other surgical approaches due to excessive bleeding. Based on this, the large single myoma is not an absolute contraindication in vNOTES myomectomy. Experienced medical institution proposed that the maximum diameter of the myoma preferably be less than 10 cm, considering the limited operating space for giant myoma [ 32 ]. One concern raised is about higher infection rate associated with vNOTES [ 9 , 32 , 33 ]. Postoperative infection mainly was associated with the vaginal entry route, which turned the class I clean wound into a class II contaminated wound [ 24 ]. The overall infection rate for vNOTES myomectomy is 6.3% (n=14), which is obviously higher than that reported in other studies [ 31 , 35 ]. A retrospective study in gynecological vNOTES found that the majority of infections occurred in the myomectomy group compared with other surgical subgroup [ 20 ]. Among 14 complications (8.38%), excepting 7 cases of anemia and 1 case of rectal injury, the remaining cases were related with infection, including 2 cases of febrile, 3 cases of pelvic abscess and 1 cases of sepsis. The infection rate is obviously higher among the surgical subgroup analysis. The reasons may be associated with longer procedure time, incomplete suture and surgical position. Medical institution recommends active use of prophylactic antibiotics and strict vaginal disinfection during the perioperative period [ 20 , 33 ]. The conversion rate also serves as a critical metric for assessing the safety and feasibility of unconventional procedure. In the vNOTES myomectomy group (n = 318), the overall conversion rate was 3.8% (n = 12) [ 9 , 14 , 16 , 24 – 33 ]. The reasons for conversion mentioned in the studies were mainly rectal injury related to pelvic adhesions, large myoma size, and the difficulty in suture related to the incision being close to the fundus of the uterus [ 25 , 33 ]. The conversion rate is higher than that of other types of gynecological disease [ 20 , 35 , 36 ]. In reported literatures, there are indeed cases where patients undergoing TU-LESS approach did not require conversion to the conventional approach [ 9 , 37 ]. Increased operational difficulty and more precise suturing may have caused the difference. Our research group is planning a multicenter prospective comparative trial to compare vNOTES myomectomy with TU-LESS myomectomy. Surgeons should undergo physical examinations and personally review imaging examinations to minimize the surgical conversion rate before performing surgery [ 33 ]. Notably, Tekin et al. reported that 2 cases with bladder injury did not require for conversion and were repaired trans-vaginally [ 14 ]. Hou et al. reported that 5 cases with intestinal injury were repaired via vNOTES and achieved good postoperative healing [ 20 ]. These findings suggest that if injury to adjacent organs occurs, such as the intestine and bladder, conversion to an alternative surgical approach is not necessary. Nevertheless, when a life-threatening injury occurs, prompt conversion to trans-abdominal surgery and subsequent repair are absolutely essential [ 33 ]. Whether by conventional laparoscopy, TU-LESS or vNOTES, treating posterior uterine myoma has always posed several challenges, such as suture and exposure. Although previous studies have demonstrate several methods, such as posterior pituitary injection, barbed suture closure and transforming perioperative care models to optimize surgical outcome [ 38 , 39 ], difficulty in backhand suturing technique and restricted exposure still have not been effectively resolved. Enhanced recovery after surgery (EARS) guidelines referred that changes in surgical approach are crucial strategy to accelerate postoperative recovery [ 39 ]. Previous studies find that posterior myoma resection in the prone position is a feasible and effective method [ 9 ]. The change happened in prone position, which enables a forehand suturing technique and a larger manipulation space, for suturing posterior fibroid. It makes the surgical field wider, the exposure more sufficient, and the suturing more ergonomic, largely avoiding insufficient suture depth and reducing the risk of postoperative complications [ 17 , 25 ]. Meanwhile, for single posterior myoma, the prone position group undergoing vNOTES myomectomy demonstrated significantly shorter operative duration, less intraoperative blood loss, and earlier exhaust time compared with the lithotomy position group (P < 0.05) [ 9 , 25 ]. However, a retrospective study, about vNOTES gynecological subgroup analysis, found that the majority of infections (3.6%) occurred in the myomectomy group [ 20 ]. The reasons may be associated with longer surgical time, incomplete suture and repeated friction in the anal area. Besides the above-stated measures to prevent infection, sterile cloth sheet need to adequately cover the perianal and other contaminated sites [ 20 ]. vNOTES approach still has several limitations in myomectomy. One limitation is that operation becomes challenging due to constraints in instrument range and viewing angle when the tumor is located at the uterine fundus, lateral side, broad ligament or close to the upper abdominal cavity [ 16 ]. Besides, vNOTES approach is more suitable for removing a single uterine myoma on the unilateral lateral wall. If a patient has multiple myoma concurrently located in the anterior and posterior uterine walls, the approach would need to make two incisions, which seriously go against the concept of minimally invasive surgery. The gynecological vNOTES has evolved from laparoscopic to robotic approach [ 40 ]. Robotic surgery can use wristed instruments and three-dimensional visualization, which makes it possible to dissect poorly accessible tissues and suture more precisely [ 30 ]. The vNOTES approach combines the advantages of robotic surgeries, making it possible to address these limitations. Another surgical challenge occurs when the uterine myoma is located near to the pelvic floor, making it difficulty in placing the port steadily. To resolve this limitation, surgeons can flexibly take out the vNOTES-port, convert to conventional vaginal surgery to remove myoma, and then suture the wound under vNOTES view. In addition, vNOTES approach is not indicated for patients with FIGO types 0−II myomas, who require hysteroscopic procedures for treatment [ 41 ]. Moreover, vNOTES consensus statement has proposed several condition as contraindications, such as rectovaginal endometriosis, pelvic radiation, and prior severe pelvic inflammatory disease [ 12 ]. Notably, high BMI (>30 kg/m 2 ) and previous history of pelvic surgery are not contraindications for this approach [ 12 , 33 ]. Since any surgical approach has limitations, surgeons need to take detailed history, conduct thorough physical examinations and review careful imaging review before performing procedure, selecting optimum approach for patients. However, the sample size in previously reported studies was relatively small. Further large-sample multicenter studies are imperative to obtain perioperative outcomes and follow-up data. The prone position provides multiple advantages, including improved surgical views, a more streamlined procedural process, reduced reliance on surgical assistants, and enhanced ergonomics [ 17 , 42 ]. However, one key consideration is the surgical management when placing patients in the prone position. The heightened pressure on anterior structures in prone position may give rise to a range of complication, including postoperative visual loss, cardiovascular dysfunction, elevated abdominal pressure and increased hemorrhagic risk [ 43 ]. Numerous studies have proposed several critical interventions to mitigate surgical complications, including optimal patient positioning (such as the jackknife position, which reduce abdominal compression), the application of supportive padding materials applied to alleviate intra-abdominal pressure and close intraoperative vigilance [ 43 – 45 ]. That said, the prone position also has limitations. It requires an additional 1-2 personnel to position the patient appropriately. Furthermore, it may not be suitable for certain patient populations, such as those with obesity and severe spinal deformities. In addition, if intraoperative conversion is necessary, careful management of patient movement is essential to avoid additional potential risk during the turning process, particularly the potential of unintended extubation or accidental removal of vascular catheters. A retrospective observational cohort study has shown that there are no grade 3-4 perineal ruptures in a total of 20 cases of vaginal delivery, and has concluded that vNOTES surgery did not increase the risk of severe vaginal lacerations and is not an indication for cesarean [ 46 ]. The overall incidence of uterine rupture was 0.43% in patients receiving myomectomy [ 47 ]. In addition, among patients with a history of myomectomy who underwent a trial of labor, the risk of uterine rupture was 0.47%. Of note, some studies showed patients walked through vaginal delivery successfully after vNOTES myomectomy [ 46 , 48 ]. However, considering the unpredictable impacts on pregnancies and sexual dysfunction, nulliparas are more likely to select trans-abdominal approach rather than transvaginal approach [ 33 , 49 ]. More clinical data are needed to prove the impact of vNOTES myomectomy on later pregnancy and delivery. VNOTES myomectomy is rarely performed in medical institutes, primarily because it demands high surgical proficiency and specialized instruments. Even seasoned surgeons need formal, hands-on training to conduct vNOTES myomectomy safely and effectively. There are some suggestions on how to improve the utilization of this approach. First, experienced medical practitioners should provide specialized training programs. As a teaching hospital with rich experience in vNOTES, our institution offers quarterly vNOTES courses, featuring theoretical sessions, live surgical demonstrations, and practical workshops. Second, it is advisable to start with vNOTES hysterectomy as the first procedure, followed by and adnexal surgery—particularly posterior approaches ( 12 ). Generally, myomectomy requires more practice than other gynecological procedures due to its need for precise surgical techniques. Moreover, based on extensive accumulated experience, careful selection of the initial case is crucial. Suggested characteristics for a straightforward first case are: a single posterior myoma (maximum diameter 6 cm), multiparous patients without prior abdominal surgery, and a BMI below 28. Nevertheless, further research is needed to analyze the learning curve associated with vNOTES myomectomy.

Uterine leiomyoma, also known as myoma, is one of most commonly encountered gynecological benign disease. The incidence rate reaches up to 70% [ 1 ]. Generally, most women with uterine myoma are asymptomatic in the early stage and are diagnosed after a physical examination. However, approximately 30% of the patients will experience various severe symptoms, such as abnormal uterine bleeding (AUB), anemia, oppression symptoms (difficulty of urination and defecation), or infertility, which severely affect quality of life of the patients [ 2 , 3 ]. The treatment of uterine leiomyomas includes medication, high-intensity focused ultrasound ablation, interventional embolization and surgical intervention [ 4 – 6 ]. Regarding surgical interventions, myomectomy is the preferred way for patients with the desire of preserving reproductive function [ 7 ]. Over the past 2 decades, the main surgical approach has gradually changed from abdominal surgery to laparoscopic surgery [ 8 ]. Owing to the rapid advancement of minimally invasive surgery, myomectomy has reached the stage of transumbilical laparoendoscopic single-site surgery (TU-LESS) and vaginal natural orifice transluminal endoscopic surgery (vNOTES) [ 9 , 10 ]. The vNOTES technology, as a more minimally invasive procedure, has developed rapidly in various surgical field. It represents an emerging approach that combines the visualization and precision offered by endoscopy while avoiding the trans-abdominal wound-related complications [ 11 , 12 ]. It has been proved as a feasible and safe option for a range of gynecological surgeries, including hysterectomy, ovarian cystectomy, adnexectomy, myomectomy, and even early-stage cancer surgery [ 13 – 15 ]. Previously published literatures rarely report the application of vNOTES in myomectomy. The reason may be related to the relatively restricted surgical view and the narrow operative space, which impose higher requirements on surgeons and surgical instruments, hereby making vNOTES myomectomy more challenging than common gynecological surgeries [ 16 ]. In this review, we aim to illustrate a standard approach and clarify the application status of vNOTES myomectomy, drawing on the experience of our institution, which has performed over 3000 vNOTES gynecological surgeries [ 17 ].