Nasal expansion in the fetal lamb: a first step toward management of cleft nasal deformity in utero

Abstract

The cleft nasal deformity, a combination of malpositioned cartilage and tissue and postrepair scarring, is a difficult problem to correct. To harness the potential of scarless fetal wound healing, in utero repair of cleft lip and palate deformities has been studied but the fetal cleft nose deformity has not been addressed. The purpose of this study was to manipulate the fetal nasal shape in utero as a first step toward restoration of normal nasal form in cleft nasal deformities. To do this, preformed hypertonic sponges were placed into the right nostril of eight fetal lambs during the second trimester (when scarless cutaneous wound repair is known to occur). Then, the size and shape of fetal nasal structures were analyzed after selected time periods (1, 2, and 6 weeks) with measurements, routine histologic examination, and three-dimensional computed tomographic scans of the experimentally expanded noses compared with the control nonexpanded noses of the birth twins or age-matched specimens. Results showed that experimentally expanded nasal structures had markedly increased in septal length measurement, in nostril area (doubled), and in intranasal volume (more than doubled). Histology showed normal cellular elements without scarring in the tissue sections from the expanded nasal areas. In conclusion, the shape of nasal tissue can be manipulated without scarring in second-trimester fetal lambs after placement of a nasal expansion device. This study is an experimental first step toward restoring normal nasal form by repositioning alar cartilages and soft tissue during fetal cleft repair.