In vivo porcine training model for laparoscopic Roux-en-Y choledochojejunostomy

Mechanism of scar formation following Roux-en-Y choledochojejunostomy in a novel rat model of obstructive jaundice

Background

The present study aimed to analyze the scar formation mechanism following Roux-en-Y choledochojejunostomy (CJS) in a novel rat model of obstructive jaundice.

Methods

The biliary obstruction model of Sprague-Dawley (SD) rats was established in advance, and 24 rats were randomly divided into 4 groups (control group, 1-day ligation group, 3-day ligation group, and 5-day ligation group). Changes in postoperative weight, common bile duct diameter, and laboratory indexes were analyzed to determine the best operation time. Roux-en-Y CJS in rats was studied based on the model, and the rats were randomly divided into 4 groups [control group, 3-day choledochojejunostomy (CJS) group, 7-day CJS group, and 30-day CJS group]. The same indexes were analyzed, and the characteristics of scar formation were evaluated by histopathology and polymerase chain reaction examination.

Results

The third day after common bile duct ligation is the best time for a Roux-en-Y CJS. The common bile duct diameter expands to 4.2 mm on average, and these physiological characteristics are consistent with current standard clinical findings. After completing CJS, the rats’ weight returned to normal levels, and alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TB), direct bilirubin (DB), and C-reactive protein (CRP) indexes gradually decreased (P<0.05). Anastomotic stoma diameter tended to narrow with time and was significantly narrower on day 30 than preoperation. After CJS, the expression of α-smooth muscle actin (α-SMA) peaked in the early stage and was still higher than that of the control group in the bile duct wall 1 month postoperatively (P<0.05). Transforming growth factor-β1 (TGF-β1) expression gradually increased and was higher than that of the control group at each stage postoperatively (P<0.05).

Conclusions

The rat Roux-en-Y CJS model is more in line with our surgical model, and the clinical condition has potential applicability for the study of CJS scar formation. Scar formation following CJS in rats is characterized by the activation of fibroblasts caused by early inflammatory stimulation, which leads to the proliferation of collagen and smooth muscle fibers, resulting in scars.

Developing an in vivo porcine model of duct-to-mucosa pancreaticojejunostomy (Yonsei-PJDTM)

Laparoscopic pancreaticoduodenectomy (LPD) is technically feasible, but its safety is still controversial. Pancreas texture and the small size of the main pancreatic duct indicate laparoscopic pancreaticoduodenectomy (LPD) as a challenging procedure. Thus, LPD could be a risk factor for postoperative pancreatic fistula (POPF), longer hospital stay, and delayed adjuvant chemotherapy that affects long-term oncologic outcome. So, it is important to promote education on LPD especially techniques for pancreaticojejunostomy. A porcine model for duct-to-mucosa pancreaticojejunostomy (PJ) (Yonsei-PJDTM) was developed, and details of the model will be described in this report.

A Novel University of North Carolina Laparoscopic Ventral Hernia Repair Simulator

Background: Simulation plays an important role in surgical training. We developed a simulator for laparoscopic ventral hernia repair (LVHR) surgery based on porcine tissue, characterized by low cost and high reality. Methods: Our LVHR model is based on porcine tissue mounted in a human mannequin. The anterior abdominal wall is constructed to allow laparoscopic training. Training sessions are conducted in a simulated operating room environment. Results: During preliminary tests, the LVHR simulator was found to be highly realistic in terms of tissue feedback, instrumentation usage, and performing the key steps of the LVHR procedure. The model was evaluated as a very useful tool for residents' training allowing to gain laparoscopic skills, learn the key steps of LVHR, and practice team work. Conclusions: Our simulator, based on porcine tissue mounted in a mannequin, offers a very realistic and cost-effective model for simulating LVHR surgery.

Development and evaluation of a novel simulation model for transabdominal preperitoneal (TAPP) inguinal hernia repair

BACKGROUND

Transabdominal preperitoneal (TAPP) inguinal hernia repair requires the surgeon to have good manual skills in laparoscopic surgery, as well as an understanding of the laparoscopic features of the groin anatomy. This is why TAPP is considered a more difficult surgical procedure compared to open techniques. Realistic training model for TAPP inguinal hernia repair would enhance surgeons' skills before they enter in the operation room. Our aim was to create a realistic, inexpensive, and easily reproducible model for laparoscopic TAPP inguinal hernia repair and to assess its effectiveness.

METHODS

The applied TAPP inguinal hernia repair training simulator consists of a laparoscopic box and an inguinal region model placed in it. The model of the groin area is made of the porcine stomach and assembling materials. Uniaxial tensile and T-peel tests were performed to compare the mechanical properties of the porcine stomach and the human cadaver peritoneum. Thirty eight surgeons performed TAPP inguinal hernia repair using this model. Their opinions were scored on a five-point Likert scale.

RESULTS

Close elastic modules of the porcine and human tissues (13.5 ± 4.2 kPa vs. 15.8 ± 6.7 kPa, p = 0.531) gave to trainees a realistic tissue feel and instrument usage. All participants strongly agreed that model was highly useful for TAPP inguinal hernia repair training. They also put the following points: the model as a whole 5 (3-5), simulation of anatomy 5 (3-5), simulation of dissection and mobilization 5 (3-5), and simulation of intracorporeal suture 5 (4-5).

CONCLUSIONS

We successfully created a model for TAPP inguinal hernia repair training. The model is made of inexpensive synthetic and biological materials similar to the human tissue. The model is easy to reproduce and can be used in the training programs of surgical residents.

Comprehensive and innovative techniques for laparoscopic choledocholithotomy: A surgical guide to successfully accomplish this advanced manipulation

Surgeries for benign diseases of the extrahepatic bile duct (EHBD) are classified as lithotomy (i.e., choledocholithotomy) or diversion (i.e., choledochojejunostomy). Because of technical challenges, laparoscopic approaches for these surgeries have not gained worldwide popularity. The right upper quadrant of the abdomen is advantageous for laparoscopic procedures, and laparoscopic choledochojejunostomy is safe and feasible. Herein, we summarize tips and pitfalls in the actual procedures of choledocholithotomy. Laparoscopic choledocholithotomy with primary closure of the transductal incision and transcystic C-tube drainage has excellent clinical outcomes; however, emergent biliary drainage without endoscopic sphincterotomy and preoperative removal of anesthetic risk factors are required. Elastic suture should never be ligated directly on the cystic duct. Interrupted suture placement is the first choice for hemostasis near the EHBD. To prevent progressive laceration of the EHBD, full-layer interrupted sutures are placed at the upper and lower edges of the transductal incision. Cholangioscopy has only two-way operation; using dedicated forceps to atraumatically grasp the cholangioscope is important for smart maneuvering. The duration of intraoperative stone clearance accounts for most of the operative time. Moreover, dedicated forceps are an important instrument for atraumatic grasping of the cholangioscope. Damage to the cholangioscope requires expensive repair. Laparoscopic approach for choledocholithotomy involves technical difficulties. I hope this document with the visual explanation and literature review will be informative for skillful surgeons.

In vivo porcine training model of laparoscopic common bile duct repair with T-tube insertion under the situation of iatrogenic common bile duct injury

Purpose

We introduce a training porcine model for laparoscopic common bile duct (CBD) repair with T-tube insertion. The model could be the feasible training tool for a surgeon learning hepatobiliary surgery.

Methods

Totally laparoscopic CBD repair with T-tube insertion was performed on 9 pigs by 9 trainees naïve in hepatobiliary surgery. Similar to the situation of iatrogenic injury, CBD was transected by laparoscopic scissors at the middle part about 1 cm in length, and the transected CBD was repaired through end-to-end anastomosis with T-tube insertion. A secureness of anastomosis was confirmed by saline leakage test and all animals were sacrificed after the surgery.

Results

All novice surgeons completed operations successfully without complications. Total mean operative time was 85 ± 1.7 minutes and the mean time spent performing the CBD repair with T-tube insertion was 71 ± 3 minutes. There was no bile leakage after primary anastomosis in all animals.

Conclusion

This porcine training model for laparoscopic CBD repair with T-tube insertion could be a feasible and effective training tool for surgeons with little experience in laparoscopic hepatobiliary surgery.