Successful sealing of fetoscopic access sites with collagen plugs in the rabbit model

The aim of this study was to evaluate the efficacies of various plugging techniques in sealing the membrane defect created by fetoscopy in the rabbit at midgestation.

Fetoscopy was performed in pregnant rabbits at 23 days' gestation (term, 32 days' gestation). In group 1 fetal sacs were left unclosed (positive control group, n = 24). In group 2 injection with commercially available extracellular matrix (Matrigel; BD Labware, Bedford, Mass) was performed and a myometrial suture was inserted (n = 23). In group 3 the entry site was plugged with collagen (Colgen; Inter-Phar, Paris, France) combined with a myometrial suture (n = 22). At 30 days' gestation the membrane integrity, amniotic fluid presence, and fetal lung/body weight ratios were assessed. The plugging site was examined histologically.

The use of suture and collagen plugs (group 3) resulted in functional restoration of membrane integrity with preservation of amniotic fluid and normal fetal lung/body weight ratio at term in 82% of cases, compared with 42% in the positive control group (group 1; P <.05). Histologic examination revealed entrapment of membranes between the plug and the myometrium but no anatomic repair of the membranes. The use of suture and extracellular matrix (group 2) did not achieve better results than those seen in group 1 (positive control group).

Collagen plugs achieved functional sealing of fetoscopic access sites in a rabbit model and prevented oligohydramnios and pulmonary hypoplasia.