TY - CHAP M1 - Book, Section TI - Chapter 11. Congenital Nasal Anomalies A1 - Suurna, Maria V. A2 - Lalwani, Anil K. PY - 2012 T2 - CURRENT Diagnosis & Treatment in Otolaryngology—Head & Neck Surgery, 3e AB - Nasal development occurs during weeks 4 through 10 of gestation. Migrating neural crest cells populate the frontonasal prominence, one of five facial prominences, and form the nasal or olfactory placodes. These placodes appear as convex thickenings on the surface ectoderm of the frontonasal prominence. A central depression deepens in the placodes to form the primitive nasal pit. Mesenchymal proliferation during the 5th week around the nasal placodes allows the horseshoe-shaped medial and lateral nasal prominences to develop and fuse to form the nostrils. The nasal pits grow toward the oral cavity and develop into the early nasal fossae. The nasobuccal membrane separates the nasal cavities from the oral cavity. This membrane subsequently disappears, allowing for communication of the nasal cavities with the oral cavity, forming the primitive posterior nasal choanae. The nasomedial process gives rise to part of the nasal septum and the medial crus of the lower lateral alar cartilage. The nasolateral process develops into the external wall of the nose, nasal bones, upper lateral cartilage, alae, and lateral crus of the lower lateral cartilage. The apex and dorsum of the nose develop from the frontonasal process (Figure 11–1). SN - PB - The McGraw-Hill Companies CY - New York, NY Y2 - 2024/04/19 UR - accessmedicine.mhmedical.com/content.aspx?aid=55766281 ER -