Anatomy of the Caucasian alar groove.

Anatomic studies performed on the noses of 15 cadavers examined the alar groove, alar lobule, and lower lateral crus areas both microscopically and on gross appearance to determine what effect these structures have on overall nasal appearance. In contrast to the findings of previous studies, the authors found the alar lobule to be an area in which dermis is interdigitated with muscle throughout and up to the alar rim. The anteroposterior lengths of the lower lateral crura were again seen to vary in length, presence or absence of accessory cartilages, and shape. Neither corrugation of the posterior elongation nor overlap of the accessory cartilages of the lower lateral cartilage had an effect on phenotype; sharp angles formed by the cartilage were blunted by the layer of fibrofatty muscular tissue between the cartilage and the skin. The alar groove, which lies at the junction of the lower lateral crus (medially) and the alar lobule (laterally), is defined not as much by a muscular attachment between the perichondrium of the lower lateral cartilage and the vestibular mucosa as by a bulging in the fatty layer on one side of the groove (within the cheek, lateral nasal wall, and nasal tip) and a relative paucity of fatty tissue on its other side (within the alar lobule).