Clinical efficacy and safety of transvaginal natural orifice transluminal endoscopic surgery for benign adnexal disease: a prospective trial

In this prospective clinical study, the authors have successfully demonstrated the feasibility and safety of Vnotes in the management of gynecological adnexal diseases, as evidenced by follow-up observations. A total of 196 patients were enrolled in the study, all of whom underwent the designated procedures. The obtained results align with the findings reported by Baekelandt J et al., who introduced a novel approach for conducting ovarian cystectomy [16]. The pivotal aspect contributing to the efficacy of vNOTES lies in the precise opening of the posterior fornix of the vagina to gain access to the abdominal cavity, with two crucial factors influencing the execution of this technique. Prior to surgery, it is imperative to conduct a thorough assessment of the posterior vaginal fornix through bimanual and trimanual examination, as well as transvaginal ultrasound. This examination should encompass evaluating the presence of sufficient vaginal access, the existence of tender nodes in the posterior vaginal fornix and posterior uterine wall, and the potential adhesion or closure of the uterorectal socket. Additionally, it is crucial to make an informed decision regarding the appropriate positioning of the incision in the posterior vaginal fornix. The proximity of the side adjacent to the cervix may result in an indistinct anatomical structure and hinder access to the abdominal cavity, whereas the side in close proximity to the rectum poses a risk of damaging the intestinal tract [17]. Consequently, certain scholars have introduced the notion of performing a “safety triangle” procedure as a potential solution.

Fortunately, no instances of rectal injury were observed among the patients in the vNOTES group during our study. Within this group, three participants with uncomplicated chocolate cysts successfully underwent the procedure. It is noteworthy that the recto-uterine pit, being the lowest point within the pelvic cavity, can serve as a site for the accumulation of ruptured bleeding and fluid originating from benign ovarian tumors. Additionally, a history of pelvic and abdominal surgeries may result in the development of severe pelvic adhesions [18]. These factors can potentially impede the entry of the posterior fornix into the abdominal cavity. Hence, it is imperative to conduct a thorough and extensive assessment of the patient’s posterior fornix prior to surgical intervention. Closure of the uterorectal fossa may occur as a result of prior pelvic surgery, documented pelvic adhesions, endometriosis lesions, pelvic inflammatory disease, or any other etiology. Consequently, individuals with a medical history of pelvic-abdominal surgery and posterior fornix adhesions were deliberately omitted from the research study. This exclusionary criterion may contribute to the observed 100% surgical success rate within the vNOTES group.

No statistically significant differences were observed in the duration of surgery and intraoperative blood loss between the vNOTES and CL groups in the adnexectomy cohorts. However, in the ovarian cystectomy cohorts, the mean duration of vNOTES was significantly shorter compared to CL. These findings align with the results reported by Lee CL et al. [19], but differ from those reported by Kaya C et al. [20]. Based on our study’s clinical practice experience and expertise in vaginal surgery, we observed a significant reduction in operation time after independently performing approximately 40 vNOTES cases. In their study on the learning curve of vNOTES for adnexal surgery, Huang YT et al. demonstrated that a gynecologist with appropriate training could achieve proficiency in surgical procedures after completing 36 vNOTES cases [21].

In comparison to the CL group, patients in the vNOTES group exhibited prompt anal exhaust following surgery, aligning with the observations made by Zhang J et al. [22]. This correlation may be attributed to the fact that the vNOTES procedure is performed in the lower pelvic region, allowing for operation under low intra-abdominal pressure or without pneumoperitoneum. Pneumoperitoneum exerts minimal impact on intestinal function, enabling certain patients to engage in bedside activities merely 6 h post-operation, thereby facilitating the restoration of intestinal function. In order to establish a secure surgical operating space and prevent harm to surrounding organs and tissues, it is necessary for CL to maintain an optimal level of CO₂ to create an ideal pneumoperitoneum environment. It has been theorized that postoperative pain following laparoscopic surgery may be attributed to the retention of CO₂ in the abdominal cavity, which subsequently irritates the phrenic nerve and diaphragm, resulting in referred pain in the shoulder and upper abdomen [23]. Despite appropriate postoperative deflation, our study observed that 28 patients experienced postoperative shoulder pain in the CL group. No reports of shoulder pain potentially associated with the vaginal incision and sufficient deflation were found in the vNOTES. Subsequent assessments indicated that diaphragm and shoulder pain could impede patients’ regular breathing patterns, but this issue gradually resolved within one month after the surgery.

The utilization of NOTES demonstrated considerable benefits in terms of postoperative pain management and wound recovery. In contrast to the mucosal nature of the posterior fornix incision, the CL involves a skin incision that often leads to noticeable scarring, particularly in the umbilicus region. The deep wound in the umbilicus hinders the patient’s ability to effectively care for the wound after being discharged from the hospital. Consequently, this situation leads to the accumulation of secretions and bacterial colonization, creating a microenvironment that promotes bacterial reproduction while impeding wound healing. In the present study, it was observed that two patients belonging to the CL group experienced infection and purulence of the umbilical port wound following the surgical procedure.

Both CL and vNOTES are considered minimally invasive surgical techniques, and there were no significant alterations in the overall health status of patients following surgery when compared to their preoperative condition. The health assessment of patients in our study was conducted using the Health Survey Short Form SF-36. The findings revealed that the vNOTES group exhibited superior postoperative health outcomes at both the 1-month and 6-month intervals compared to the CL group. This disparity may be attributed to reduced surgical trauma, diminished pain, and expedited postoperative recovery associated with the vNOTES approach. In the groups undergoing ovarian cystectomy, the vNOTES group exhibited superior postoperative sexual function outcomes compared to the control group, with a statistically significant difference. These findings align with the research conducted by Linke GR et al. [24], which similarly reported no evidence of infertility or dyspareunia as long-term complications following vNOTES [25]. However, in the context of absorbable sutures and wound healing, it is recommended that patients abstain from engaging in sexual intercourse for a minimum duration of six weeks following surgery.

It is important to acknowledge several limitations inherent in our study. Firstly, this trial was conducted at a single center, with all procedures performed by a single expert surgeon, thereby restricting the generalizability of our findings. Additionally, blinding was not feasible in surgical trials due to the unique nature of the procedure. Furthermore, the postoperative follow-up results may be subject to bias stemming from patients’ limited understanding of the surgical methodology. Furthermore, the scope of this study is restricted to the Chinese population, thereby potentially compromising the generalizability of the findings on a global scale.