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The role of a computed tomography-based image registered navigation system for natural orifice transluminal
G Fernández-Esparrach1, R San José Estépar, C Guarner-Argente
1Endoscopy Unit, Department of Gastroenterology, Hospital Clinic, University of Barcelona, IDIBAPS, CIBERehd, Barcelona, Spain. mgfernan@clinic.ub.es
Background And Study Aims:
Most natural orifice transluminal endoscopic surgery (NOTES) procedures have been performed in animal models through the anterior stomach wall, but this approach does not provide efficient access to all anatomic areas of interest. Moreover, injury of the adjacent structures has been reported when using a blind access. The aim of the current study was to assess the utility of a CT-based (CT: computed tomography) image registered navigation system in identifying safe gastrointestinal access sites for NOTES and identifying intraperitoneal structures.
Methods:
A total of 30 access procedures were performed in 30 pigs: anterior gastric wall (n = 10), posterior gastric wall (n = 10), and anterior rectal wall (n = 10). Of these, 15 procedures used image registered guidance (IR-NOTES) and 15 procedures used a blind access (NOTES only). Timed abdominal exploration was performed with identification of 11 organs. The location of the endoscopic tip was tracked using an electromagnetic tracking system and was recorded for each case. Necropsy was performed immediately after the procedure. The primary outcome was the rate of complications; secondary outcome variables were number of organs identified and kinematic measurements.
Results:
A total of 30 animals weighting a mean (± SD) of 30.2 ± 6.8 kg were included in the study. The incision point was correctly placed in 11 out of 15 animals in each group (73.3 %). The mean peritoneoscopy time and the number of properly identified organs were equivalent in the two groups. There were eight minor complications (26.7 %), two (13.3 %) in the IR-NOTES group and six (40.0 %) in the NOTES only group ( P = n. s.). Characteristics of the endoscope tip path showed a statistically significant improvement in trajectory smoothness of motion for all organs in the IR-NOTES group.
Conclusion:
The image registered system appears to be feasible in NOTES procedures and results from this study suggest that image registered guidance might be useful for supporting navigation with an increased smoothness of motion.
Insights
Image-guided navigation for natural orifice transluminal endoscopic surgery (NOTES) in pigs improved access safety and reduced complications. This system enhances endoscopic tip path smoothness, offering a safer approach for complex procedures.
Area of Science:
- Minimally Invasive Surgery
- Surgical Navigation Systems
- Gastroenterology
Background:
- Natural orifice transluminal endoscopic surgery (NOTES) often uses anterior gastric wall access, limiting anatomical reach and risking adjacent structure injury.
- Blind access in NOTES procedures has been associated with complications and challenges in identifying intraperitoneal structures.
Purpose of the Study:
- To evaluate a computed tomography (CT)-based image-registered navigation system for identifying safe gastrointestinal access sites in NOTES.
- To assess the system's utility in identifying intraperitoneal structures during NOTES procedures.
Main Methods:
- Thirty pigs underwent 30 access procedures: anterior gastric wall (10), posterior gastric wall (10), and anterior rectal wall (10).
- Fifteen procedures utilized image-registered navigation (IR-NOTES), while 15 used blind access (NOTES only).
- Complications, organ identification, and endoscopic tip path kinematics were recorded.
Main Results:
- The image-registered system showed a trend towards fewer minor complications (13.3% in IR-NOTES vs. 40.0% in NOTES only).
- While peritoneoscopy time and organ identification were similar, the IR-NOTES group demonstrated statistically significant improvement in endoscopic tip path smoothness.
Conclusions:
- The CT-based image-registered navigation system is feasible for NOTES procedures.
- Image-registered guidance appears beneficial for supporting navigation, enhancing smoothness of motion, and potentially improving safety in NOTES.
