Advancing flexible endoscopy to natural orifice transluminal endoscopic surgery

An EM-Tracked Approach for Calibrating the 3D Pose of Flexible Endoscopes

Flexible endoscopes are ideal instruments for visualizing and diagnosing the inner surfaces of organs via a minimally invasive incision. Calibrating a flexible endoscope is a troublesome yet inevitable process in image-based tools tracking. Aiming to simplify the calibration process, we propose an electromagnetic (EM)-tracked calibration approach that does not require any predefined poses of the EM sensor. A three-stage calibration protocol was presented in an extensor. First, the orientation of the endoscope tube was derived by conducting a circular rotation of the endoscope around its axis utilizing a pair of tightly bearing stands. Second, the 3D position of the endoscope tip was acquired by having the tip come into contact with a flat plane. Third, the pose model of the bending section was derived and transformed into the local coordinate system of the EM sensor attached to the endoscope handle. To assess the accuracy of the proposed calibration approach, two experiments were designed and performed. Experimental results indicate accuracies of 0.09 ± 0.06 deg and 0.03 ± 0.19 deg in the estimation of the endoscope tube orientation and 0.52 ± 0.29, 0.33 ± 0.11, and 0.29 ± 0.17 mm in the x, y, and z estimations of the endoscope tip position, respectively. The proposed approach is accurate and easy to operate, does not require the employment of custom calibration markers, and can be used not only in surgical training systems but also in the endoscopic-based tools tracking.

A safe and effective endoscopic treatment method for simple hepatic cysts (with video)

Background and study aims Symptomatic simple hepatic cysts require treatment, with several guidelines recommending laparoscopic deroofing. However, cysts located in the posterosuperior segments are considered poor candidates for this procedure. Gastrointestinal endoscopes are more flexible and able to reach less accessible areas than laparoscopes. This study aimed to evaluate the utility of endoscopic transgastric hepatic cyst deroofing (ETGHCD) for treatment of simple hepatic cysts. Patients and methods Seven patients with simple hepatic cysts were evaluated between June 2021 and October 2023. The success rate, procedure time, post-procedure length of hospital stays, complications, pathologic diagnosis, and efficacy were recorded. Results Eleven cysts in seven patients (5 men; mean age 65.5 (standard deviation [SD] 8.5) years) were successfully treated without any complications. The mean procedure time was 65.6 minutes (SD 17.2). Mean post-procedure hospitalization was 4.4 days (SD 1.0). The pathologic diagnosis of 11 cysts showed simple hepatic cysts. The size of the cysts was significantly decreased from 337.0 cm 3 (SD 528.8) to 5.2 cm 3 (SD 6.3) 1 month after ETGHCD. During the median 12.7-month follow-up in seven patients, the cysts showed a 99.6% reduction with no recurrence. Conclusions ETGHCD provided a feasible, safe, effective, and minimal invasive alternative approach for the treatment of simple hepatic cysts.

Transgastric versus transrectal: Which access route is the best for NOTES gallbladder-preserving gallstone therapy?

OBJECTIVES

To compare the effectiveness and safety of transgastric and transrectal pure natural orifice transluminal endoscopic surgery (NOTES) for cholecystolithotomy.

METHODS

This was a single-center retrospective comparative study of consecutive patients who underwent pure NOTES for either transrectal or transgastric gallbladder-preserving cholecystolithotomy between September 2017 and April 2020. Patients with symptomatic cholelithiasis were assigned for transrectal or transgastric NOTES based on the patients' choice. Treatment success, postoperative pain, peritonitis, time to resume normal diet, and duration of hospitalization were compared.

RESULTS

The technical success rate was 100%. Forty-eight patients underwent successful NOTES cholecystolithotomy via the transrectal (n = 26) or transgastric route (n = 22). One (3.8%) patient in the transrectal NOTES group experienced postoperative abdominal pain compared to 6 (27.3%) in the transgastric NOTES group (P = 0.04). Fever and bile peritonitis developed in one (3.8%) patient in the transrectal NOTES group versus 8 (36.4%) in the transgastric NOTES group (P = 0.005). A postoperative fluid diet was commenced at 6 h with the transrectal approach versus on day 3 for the transgastric NOTES group. The mean postoperative hospitalization for transrectal and transgastric NOTES groups was 4.5 days versus 7 days (P = 0.001). Three patients in the transgastric NOTES group developed postoperative gastric fistula.

CONCLUSIONS

Transrectal NOTES has advantages over transgastric NOTES, including preserved spatial orientation, relatively easier removal of specimens, early food intake, shorter hospitalization, fewer postoperative complications and less pain. Multicenter clinical trials with long-term follow-up are needed to confirm the safety and efficacy of both approaches.

Update on the natural orifice transluminal endoscopic surgery for gallbladder preserving gallstones therapy: A review

Cholecystectomy remains the "gold standard" for the management of symptomatic gallstones. Minimally invasive laparoscopic cholecystectomy has been the treatment of choice for the past 3 decades. However, the technique of natural orifice transluminal endoscopic surgery cholecystolithotomy is evolving, with some experts advocating gallbladder stone removal without gallbladder excision in order to preserve gallbladder function and eliminate post-cholecystectomy syndromes, including complications of the surgical incision, bile duct injury, functional gastrointestinal, and psychological conditions, and possibly an increase in colon cancer. In addition, transluminal endoscopic cholecystolithotomy is an option for elderly patients who are not suitable candidates for open surgery and those who desire scar-free minimally invasive surgery with organ preservation. This article summarizes the established pure natural orifice transluminal endoscopic surgery gallbladder preserving gallstone removal techniques and highlights the pros and cons of different popular available endoscopic approaches to gallstone therapy and how flexible endoscopic surgery via the natural orifice is compared to the well-established cholecystectomy.

Conventional three-port laparoscopic appendectomy versus transumbilical and suprapubic single-incision laparoscopic appendectomy using only conventional laparoscopic instruments

PURPOSE

Single-incision laparoscopic appendectomy (SILA) is usually performed using single-port instruments, which may restrict its development and application. This study explored the performance of transumbilical SILA (TSILA) and suprapubic SILA (SSILA) using only conventional laparoscopic instruments and compared them with conventional three-hole/port laparoscopic appendectomy (CLA).

METHODS

This retrospective study included 174 patients who underwent CLA, TSILA, or SSILA for acute appendicitis at our hospital between June 2019 and July 2021. Demographic data and clinical outcomes were compared among the three groups.

RESULTS

Compared with CLA, TSILA was associated with significant reductions in postoperative pain, length of hospital stay, and hospital cost, while SSILA was associated with significant reductions in length of hospital stay and hospital cost (all P < 0.05). Significantly more patients in the two SILA groups were cosmetically satisfied than those in the CLA group (all P < 0.05). However, compared with CLA, SSILA required a significantly longer operative time (65.3 ± 24.1 vs 56.5 ± 20.9, P = 0.039). Besides, compared with TSILA, SSILA showed significantly higher postoperative pain score (2 ± 2 vs 3 ± 2, P = 0.006). Mild incisional or intraabdominal infections were noticed in 2 (3.0%) patients in the CLA group, 3 (5.1%) in the TSILA group, and 3 (6.3%) in the SSILA group (P = 0.69).

CONCLUSION

SILA performed with only conventional laparoscopic instruments was associated with reduced hospital stay and cost and higher cosmetic satisfaction in comparison to CLA. However, it is technically demanding and may increase operative time.

Colon Sparing Endoscopic Full-Thickness Resection for Advanced Colorectal Lesions: Is It Time for Global Adoption?

The majority of colon lesions are <10 mm in size and are easily resected by endoscopists with appropriate basic training. Lesions ≥10 mm in size are difficult to remove technically and are associated with higher rates of incomplete resection. Currently, the main endoscopic approaches include endoscopic mucosal resection (EMR) for lesions without submucosal invasion, and endoscopic submucosal dissection (ESD) for relatively larger lesions involving the superficial submucosal layer. Both of these approaches have limitations, EMR cannot reliably ensure complete resection for larger tumors and recurrence is a key limitation. ESD reliably provides complete resection and an accurate pathological diagnosis but is associated with risk such as perforation or bleeding. In addition, both EMR and ESD may be ineffective in treating subepithelial lesions that extend beyond the submucosa. Endoscopic full-thickness resection (EFTR) is an emerging innovative endoscopic therapy which was developed to overcome the limitations of EMR and ESD. Advantages include enabling a transmural resection, complete resection of complex colorectal lesions involving the mucosa to the muscularis propria. Recent studies comparing EFTR with current resection techniques and radical surgery for relatively complicated and larger lesion have provided promising results. If the current trajectory of research and development is maintained, EFTR will likely to become a strong contender as an alternative standard of care for advanced colonic lesions. In the current study we aimed to address this need, and highlighted the areas of future research, while stressing the need for multinational collaboration provide the steppingstone(s) needed to bring EFTR to the mainstream.