NOTES: approach to the liver and spleen.
BACKGROUND
Minimally invasive abdominal surgery means minimal trauma to the abdominal wall, thus reducing postoperative pain and wound complications, and facilitating earlier mobilization and shorter hospitalization in comparison with conventional surgery. Natural orifice translumenal endoscopic surgery (NOTES) has the potential to further reduce the invasiveness of surgery in human patients. Here we report an experimental study of NOTES to access the liver and spleen, discuss its current status, and review the related literature.


METHODS
The utility of transgastric peritoneoscopy was evaluated using one 15-kg pig and four 8-kg dogs on the basis of acute experiments. Under general anesthesia with endotracheal intubation, a forward-viewing, double-channel endoscope was advanced into the peritoneal cavity through a gastric hole. Liver biopsy from the edge of the liver was performed using routine biopsy forceps. Splenectomy was performed using a laparoscopically assisted procedure, and then the spleen was pulled into the stomach using an endoscopic polypectomy snare after enlargement of the gastric orifice. The animals were then sacrificed and necropsy was performed.


RESULTS
There were no complications during incision of the gastric wall and entry into the peritoneal cavity. Peritoneoscopy gave satisfactory visualization of the abdominal cavity in all directions. Liver biopsy was performed successfully without any bleeding and adequate samples were obtained in all cases. Splenectomies were also accomplished uneventfully, except for injury of the splenic parenchyma due to excessive force during pulling into the stomach. Necropsy revealed no particular damage to other intraperitoneal organs related to this transgastric procedure.


CONCLUSIONS
Although NOTES is a feasible procedure and offers several advantages to patients, surgeons and endoscopists need to resolve several key issues before its clinical introduction for routine surgical work and to establish a training system for NOTES in order to avoid critical complications.
Tagaya
Nobumi
N
Second Department of Surgery, Dokkyo Medical University, 880 Kitakobayashi, Mibu, Tochigi, 321-0293, Japan. tagaya@dokkyomed.ac.jp
Kubota
Keiichi
K
D000818:Animals; D001707:Biopsy, Needle; D004285:Dogs; D019723:Endoscopes; D016145:Endoscopy, Digestive System / Q000379:methods*; D006498:Hepatectomy / Q000379:methods*; D010535:Laparoscopy / Q000379:methods; D008099:Liver / Q000601:surgery; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D023421:Models, Animal; D012680:Sensitivity and Specificity; D013154:Spleen / Q000601:surgery; D013156:Splenectomy / Q000379:methods*; D013552:Swine