Delayed Intrauterine Repair of an Experimental Spina Bifida with a Collagen Biomatrix

Abstract

Background/Purpose: The aim of the study was to evaluate whether a collagen biomatrix is useful for delayed intrauterine coverage of a surgically created spina bifida in a fetal lamb. Methods: In 20 fetal lambs, surgery was performed at 72 or 79 days’ gestation. In 15 lambs a spina bifida was created surgically. In 8 lambs it was covered with a collagen biomatrix 2 weeks later and in 7 lambs it was left uncovered. Five lambs served as sham operated controls. Neurological examination was performed at 1 week of age and afterwards the lambs were sacrificed for further histological evaluation. Results: None of the 5 surviving lambs with the defect covered showed loss of spinal function and the architecture of the spinal cord was preserved in 4 of the 5 lambs. In the uncovered group, 1 of the 4 surviving lambs had loss of spinal function, 5 lambs were available for histological evaluation and 4 of them showed disturbance of the architecture of the spinal cord. Conclusions: Collagen biomatrices can be used for intrauterine coverage of an experimental spina bifida and can preserve the architecture of the spinal cord. Neurological outcome is not different between fetuses with their spinal cord covered and fetuses with uncovered cords.

Intra-uterine tissue engineering of full-thickness skin defects in a fetal sheep model

“…Eleven lambs were evaluated; four in group 1 (93 days), three in group 2 (107 days) and four in group 3 (140 days). The survival rate was similar to previously published data for fetal surgery on similarly aged fetal lambs [5][6][7].…”

“…For this purpose we developed a fetal skin defect model in sheep, and treated the defects with a cross-linked type I collagen scaffold (which was previously applied in a rat model and sheep model [4][5][6][7]). Collagen scaffolds can be modulated in different ways to enhance and regulate wound healing.…”

Development of a Locomotor Rating Scale for Testing Motor Function in Sheep

“…Several studies have reported performing thorough neurologic exams in the fetal sheep model, but the reported data focus on the incidence of paraplegia [9][10][11][12][13]. While the ultimate goal of MMC research may be to cure paralysis, the gradations of functional recovery are more complex and require more nuanced categorization than simply ambulatory versus non-ambulatory.…”

Tissue Engineering Strategies for Fetal Myelomeningocele Repair in Animal Models

“…To date, experimental studies of tissue engineering approaches to prenatal repair of MMC can be divided into 2 groups according to the goals of the investigators: (1) to prevent amniotic fluid-induced neural damage by providing coverage of the defect using scaffolds [31,32,33,34,35,36,37,38] and (2) to place a scaffold and/or cells between the neural tissue and the skin repair to prevent adhesion of the repair to the cord (tethering) and/or to provide neurotrophic factors or regenerate neural tissue [39,40,41,42,43,44]. …”