Recent advances in obstetric ultrasoundhave stimulatedinnovative interventions in fetal surgery. Myelomeningocele (MMC) is a promising target lesion in this fieldbecause in many cases, the defect is not structurally complicated, andusually, there are no associations with other serious disorders, including genetic abnormalities. Therefore, prenatal surgical repair of MMC is likely to lead to life-long improvements in terms of postnatal quality of life. However, since a fetus is not a small infant from the pathophysiological viewpoint, the most appropriate surgical procedure would not be a conventional one that has been employedd uring the postnatal periodin the past. In this report, we attempted to cover the defect experimentally using a collagen sheet made of highly dense type-I collagen fibrils (collagen vitrigel membrane). We hope to prevent the development of encephalomyelopathly before birth by protecting the exposed spinal cord from intrauterine chemical and/or mechanical damages causedby persistent contact with the amniotic fluidand /or inside uterine tissues andblocking cerebrospinal fluidloss through the open neural tube, thus ameliorating the Chiari II malformation. In our in vitro study, the heat-adhesive collagen membrane could be attached accurately onto the target animal tissue by laser light irradiation. Furthermore, there was increased attachment of the membrane with the combineduse of photopolymerizing chitosan as an additional adhesive. Considering all the results, it seemedprobable that both of these modalities were feasible for endoscopic surgery. Histological examination showedthat there was inward growth of the 2 predominant dermal cellular components-fibroblasts andkeratinocytes-into the collagen vitrigel membrane. In conclusion, collagen vitrigel membrane can effectively seal a skin defect based on a non-suturing mode of action. This membrane is a promising material for future endoscopic repair of fetal MMC.
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