Two-port access versus four-port access laparoscopic ovarian cystectomy

Comparing outcomes of ovarian cystectomy by vaginal natural orifice transluminal endoscopic surgery versus laparoendoscopic single-site surgery: A retrospective cohort study

BACKGROUND

We aimed to compare the outcomes of ovarian cystectomy (OC) performed by vaginal natural orifice transluminal endoscopic surgery (vNOTES) vs transumbilical laparoendoscopic single-site surgery (LESS).

METHODS

We retrospectively analyzed the data of patients in our hospital who underwent OC either by vNOTES or LESS between January 2015 and September 2021. Demographic data were collected. The primary outcome was the conversion rate. The secondary outcomes were the duration of surgery, length of hospital stay, estimated blood loss, maximum body temperature within 48 hours after operation, and duration of maximum body temperature (hours), among others. Statistical analysis was done using the SPSS software.

RESULTS

Exactly 284 patients were screened. The vNOTES and LESS groups consisted of 21 and 47 patients, respectively. There was no significant difference in the conversion rates between the two groups (0 vs 8.5% in vNOTES and LESS, respectively; p = 0.303). Compared with the vNOTES group, the LESS group had a larger cyst diameter (6.00 ± 2.32 vs 4.69 ± 1.29 cm; p = 0.004), more endometriotic cysts (42.6% vs 9.5%; p < 0.001), and more pelvic adhesions requiring adhesiolysis (57.4% vs 19.0%; p = 0.003). At baseline, there were no other differences between the groups. The secondary outcomes included a shorter duration of surgery (70.14 ± 27.30 vs 99.57 ± 36.26 minutes; p = 0.001) and lower estimated blood loss (64.29 ± 39.19 vs 163.43 ± 251.20 mL; p = 0.011) in the vNOTES group. Regression analysis showed the diameter of the ovarian cyst correlated with surgical time. The complication was comparable between the two groups.

CONCLUSION

Above all, the advantages of vNOTES include an absence of visible scars, shorter surgical duration, and less blood loss when compared with LESS. Further large-scale prospective trials should confirm the results of our study.

Development of stereo endoscope system with its innovative master interface for continuous surgical operation

Background

Although robotic laparoscopic surgery has various benefits when compared with conventional open surgery and minimally invasive surgery, it also has issues to overcome and one of the issues is the discontinuous surgical flow that occurs whenever control is swapped between the endoscope system and the operating robot arm system. This can lead to problems such as collision between surgical instruments, injury to patients, and increased operation time. To achieve continuous surgical operation, a wireless controllable stereo endoscope system is proposed which enables the simultaneous control of the operating robot arm system and the endoscope system.

Methods

The proposed system consists of two improved novel master interfaces (iNMIs), a four-degrees of freedom (4-DOFs) endoscope control system (ECS), and a simple three-dimensional (3D) endoscope. In order to simultaneously control the proposed system and patient side manipulators of da Vinci research kit (dVRK), the iNMIs are installed to the master tool manipulators of dVRK system. The 4-DOFs ECS consists of four servo motors and employs a two-parallel link structure to provide translational and fulcrum point motion to the simple 3D endoscope. The images acquired by the endoscope undergo stereo calibration and rectification to provide a clear 3D vision to the surgeon as available in clinically used da Vinci surgical robot systems. Tests designed to verify the accuracy, data transfer time, and power consumption of the iNMIs were performed. The workspace was calculated to estimate clinical applicability and a modified peg transfer task was conducted with three novice volunteers.

Results

The iNMIs operated for 317 min and moved in accordance with the surgeon’s desire with a mean latency of 5 ms. The workspace was calculated to be 20378.3 cm³, which exceeds the reference workspace of 549.5 cm³. The novice volunteers were able to successfully execute the modified peg transfer task designed to evaluate the proposed system’s overall performance.

Conclusions

The experimental results verify that the proposed 3D endoscope system enables continuous surgical flow. The workspace is suitable for the performance of numerous types of surgeries. Therefore, the proposed system is expected to provide much higher safety and efficacy for current surgical robot systems.

A development of assistant surgical robot system based on surgical-operation-by-wire and hands-on-throttle-and-stick

BACKGROUND

Robot-assisted laparoscopic surgery offers several advantages compared with open surgery and conventional minimally invasive surgery. However, one issue that needs to be resolved is a collision between the robot arm and the assistant instrument. This is mostly caused by miscommunication between the surgeon and the assistant. To resolve this limitation, an assistant surgical robot system that can be simultaneously manipulated via a wireless controller is proposed to allow the surgeon to control the assistant instrument.

METHODS

The system comprises two novel master interfaces (NMIs), a surgical instrument with a gripper actuated by a micromotor, and 6-axis robot arm. Two NMIs are attached to master tool manipulators of da Vinci research kit (dVRK) to control the proposed system simultaneously with patient side manipulators of dVRK. The developments of the surgical instrument and NMI are based on surgical-operation-by-wire concept and hands-on-throttle-and-stick concept from the earlier research, respectively. Tests for checking the accuracy, latency, and power consumption of the NMI are performed. The gripping force, reaction time, and durability are assessed to validate the surgical instrument. The workspace is calculated for estimating the clinical applicability. A simple peg task using the fundamentals of laparoscopic surgery board and an in vitro test are executed with three novice volunteers.

RESULTS

The NMI was operated for 185 min and reflected the surgeon's decision successfully with a mean latency of 132 ms. The gripping force of the surgical instrument was comparable to that of conventional systems and was consistent even after 1000 times of gripping motion. The reaction time was 0.4 s. The workspace was calculated to be 8397.4 cm(3). Recruited volunteers were able to execute the simple peg task within the cut-off time and successfully performed the in vitro test without any collision.

CONCLUSIONS

Various experiments were conducted and it is verified that the proposed assistant surgical robot system enables collision-free and simultaneous operation of the dVRK's robot arm and the proposed assistant robot arm. The workspace is appropriate for the performance of various kinds of surgeries. Therefore, the proposed system is expected to provide higher safety and effectiveness for the current surgical robot system.

Effect on ovarian reserve of hemostasis by bipolar coagulation versus suture during laparoendoscopic single-site cystectomy for ovarian endometriomas

STUDY OBJECTIVE

To compare the postoperative decrease in ovarian reserve between hemostasis by bipolar coagulation and suture during laparoendoscopic single-site cystectomy (LESS-C) for ovarian endometriomas.

DESIGN

Prospective comparative study (Canadian Task Force Classification II-1).

SETTING

University hospital.

PATIENTS

One hundred twenty-five patients with ovarian endometriomas.

INTERVENTIONS

Patients with endometrioma were managed by hemostasis with either bipolar coagulation (n = 62) or suturing (n = 63) during LESS-C. We evaluated the impact of surgery on ovarian reserve using serum anti-Müllerian hormone (AMH) levels, which were measured before surgery and 3 months after surgery in all patients.

MEASUREMENT AND MAIN RESULTS

Baseline characteristics such as age, bilaterality of endometriomas, and preoperative AMH levels were similar between the 2 study groups. There were also no differences between the 2 groups in surgical outcomes, such as operative time, operative blood loss, or operative complications. In both study groups, postoperative AMH levels were lower than preoperative AMH levels (p < .001). The decline rate of AMH levels was significantly greater in the bipolar coagulation group than in the suture group (42.2% [interquartile range, 16.5%-53.0%] and 24.6% [interquartile range, 11.6%-37.0%], respectively, p = .001).

CONCLUSION

Hemostasis by bipolar coagulation after stripping of the endometrioma during LESS-C reduces ovarian reserve more than suturing does, as determined by serial AMH levels. Therefore, suturing may be a better hemostatic choice after stripping ovarian endometriomas.