Laparoscopic percutaneous extraperitoneal closure for inguinal hernia: learning curve for attending surgeons and residents.

BACKGROUND/PURPOSE: Laparoscopic percutaneous extraperitoneal closure (LPEC) for pediatric inguinal hernia is a simple technique in which a purse-string suture made of nonabsorbable material is placed extraperitoneally around the hernia orifice by a special suture needle (Lapaherclosure™). Concerns have been raised about the extensive learning curve for both attending surgeons and residents to master this technique. This study assesses the difference in learning curves for the safe performance of LPEC by attending surgeons and residents. METHODS: A retrospective analysis was performed on the surgical charts of 409 consecutive patients (175 girls, 234 boys) who had undergone LPEC for inguinal hernia repair from December 2005 to December 2011 at Jikei University Hospital. The number of operation needed by attending surgeons and residents to reach the appropriate operation time was analyzed by the Mann-Whitney U test. RESULTS: LPEC was performed by three attending surgeons and four residents who had not previously performed LPEC. The standard operation time for LPEC by attending surgeons who have performed more than 100 LPEC cases safely is 30 min. In our study, the attending surgeons needed a mean of 12 operations (range, 10-16) to reach 30 min for LPEC. Three residents needed a mean of 31 operations (range, 27-33) to reach 30 min for LPEC. The fourth resident could not perform LPEC in 30 min or less. The difference between the number of operations needed by the attending surgeons and the residents to perform LPEC safely was statistically significant (P < 0.05). The overall incidence of contralateral patent processus vaginalis was 47.9 %. CONCLUSIONS: Our learning curve analysis showed that whereas attending surgeons needed a mean of 12 operations to perform LPEC repairs safely in 30 min or less, residents needed more than 30 operations to safely perform LPEC repairs without supervision.

Successful in utero gene transfer using a gene gun in midgestational mouse fetuses.

BACKGROUND/PURPOSE: In utero gene therapy offers a number of potential advantages over postnatal gene therapy. A latest method of gene transfer to fetuses in utero uses a new tool called a gene gun. The gene gun is less invasive and simpler than other in utero methods. The current study was designed to determine whether the gene gun is an effective tool for transferring genes to mouse fetuses in utero. METHODS: Using a gene gun, we transferred plasmids that included enhanced green fluorescent protein (EGFP) genes and cytomegalo virus promoters to the abdominal skin of 40 A/J fetal mice at each of 3 gestational ages (13, 14, or 15 days). Four or 5 days after gene transfer, the number of surviving fetuses was counted, and a color image of EGFP in the skin was analyzed for gene transfer rates by fluorescence microscopy. Survival rates were analyzed using Fisher's Exact test. RESULTS: The mean survival rate was 89.2% (107 of 120) in gene transfer fetuses and 91.7% (55 of 60) in controls. There is no difference in survival rate between gene transfer fetus and control. The highest gene transfer rate was 100% (37 of 37) at the gestational age of 14 days. The rate was 97.1% (34 of 35) at gestational ages of 13 and 15 days. CONCLUSIONS: The results of this study show that in utero gene transfer by gene gun is a less-invasive technique, and the gene gun is an effective tool transferring genes to mouse fetuses in utero.