A recommended laparoscopic procedure for implantation of microcapsules in the peritoneal cavity of non-human primates

BACKGROUND

The anatomical spatial distribution of microencapsulated islets transplanted into the peritoneal cavity of large animals remains a relatively unexplored area of study. In this study, we developed a new implantation approach using laparoscopy in order to avoid microcapsule amalgamation. This approach constitutes a clinically relevant method, which can be used to evaluate the distribution and in vivo biocompatibility of various types of transplanted microcapsules in the future.

MATERIALS AND METHODS

Two healthy baboons were implanted intraperitoneally with microencapsulated islets through mini-laparotomy and observed at 76 d after implantation. Nine baboons underwent laparoscopic implantation of approximately 80,000 empty microcapsules. Microcapsule distribution was observed by laparoscopic camera during and after implantation at 1, 2, and 4 wk. At each time point, microcapsules were retrieved and evaluated with brightfield microscopy and histologic analysis.

RESULTS

Mini-laparotomic implantation resulted in microcapusle aggregation in both baboons. In contrast, laparoscopic implantation resulted in even distribution of microcapsules throughout the peritoneum without sedimentation to the Douglas space in all animals. In eight out of nine animals, retrieved microcapsules were evenly distributed in the peritoneal cavity and presented with no pericapsular overgrowth and easily washed out during laparoscopic procedure. The one exception was attributed to microcapsule contamination with blood from the abdominal wall following trocar insertion.

CONCLUSIONS

Laparoscopic implantation of microcapsules in non-human primates can be successfully performed and prevents microcapsule aggregation. Given the current widespread clinical application of laparoscopy, we propose that this presented laparoscopy technique could be applied in future clinical trials of microencapsulated islet transplantation.

A Pelvic Hernia Through Two Defects in the Pouch of Douglas in a Patient With Peritoneal Xanogranuloma: A Report of a Very Rare Case

Pelvic internal hernias, including pouch of Douglas hernias, are a very rare cause of small bowel obstruction. They pose a challenge in diagnosis due to their rarity and lack of specific radiological features. The definitive diagnosis is usually reached intraoperatively. The treatment consists of reduction with or without resection of the herniated bowel and primary repair of the defect. Mesh placement has been reported but is still arguable, as no musculofacial defect is involved. Here, we present a case of a 28-year-old female patient, a nulliparous with multiple medical conditions including familial Mediterranean fever (FMF) and an extremely rare tumor, peritoneal xanthogranuloma. She had a history of laparoscopic left ovarian cystectomy, and complained of abdominal pain and distention for three days prior to admission. Her symptoms were associated with constipation and recurrent vomiting and she was admitted as a suspected case of small bowel obstruction. CT scan suggested the possible diagnosis of a pelvic hernia, yet the definitive diagnosis was reached intraoperatively after noticing the presence of two defects on the left side of the pouch of Douglas. A primary repair of the defects was performed after reduction of the viable herniated bowel. The patient was discharged on the third postoperative day with uneventful course of recovery.

Small Bowel Obstruction Due to Concurrent Petersen's and Pouch of Douglas Hernias in a Patient With a Complex Surgical History: A Rare Surgical Case

Internal hernias are a rare but significant cause of small bowel obstruction, particularly in patients with a history of abdominal surgery such as Roux-en-Y gastric bypass (RYGB). Although Petersen's hernia is the most commonly encountered internal hernia in these patients, herniation into the Pouch of Douglas is an exceedingly rare occurrence. This report describes the case of a 77-year-old female with a complex surgical history, including RYGB and hysterectomy, who presented with several months of postprandial abdominal pain, nausea, and vomiting. A computed tomography (CT) scan initially suggested mild bowel distention without clear evidence of obstruction. However, due to the inability to tolerate oral intake, a follow-up CT scan was performed and revealed dilated loops of the small bowel, prompting surgical intervention. Intraoperatively, two internal hernias were identified: one at Petersen's defect and another in the Pouch of Douglas, the latter being the cause of the obstruction. Both hernias were reduced, and the peritoneal defect in the Pouch of Douglas was closed using sutures. The patient recovered without complications and was discharged to rehabilitation. This case demonstrates the importance of considering internal hernias, including rare types, in post-surgical patients presenting with nonspecific symptoms of bowel obstruction. Early diagnosis and timely surgical management are crucial to prevent complications such as bowel ischemia and to ensure optimal outcomes. Closing peritoneal defects during hernia repairs is essential to minimize the risk of recurrence. This case contributes to the limited literature on internal hernias involving the Pouch of Douglas and emphasizes the need for thorough diagnostic evaluation in complex clinical scenarios.