Nasalis, Lateral View

Description

Beginning at the nasal bone and extending onto the lateral nasal cartilage, the nasalis is rendered in lateral profile with its transverse (compressor naris) fibers coursing posterior to anterior across the dorsum of the nose, and its alar part investing the ala to influence the external naris. Superiorly, the muscle lies inferior to the bony bridge and blends with adjacent superficial facial musculature near the nasal sidewall, while inferiorly it approaches the margin of the nostril and the nasolabial region. Posterior and inferior to the nose, the masseter occupies the lateral ramus of the mandible, and the temporalis fans across the temporal fossa, giving bony landmarks for orientation. A partial auricle is visible lateral to the cranial base. For teaching facial expression muscles, a true lateral view clarifies how the nasalis differs from the levator labii superioris alaeque nasi, which runs more vertically along the side of the nose, and from orbicularis oris, which encircles the oral fissure. Small muscle, real consequences. In rhinoplasty and alar base procedures, the relationship of the compressor naris and alar fibers to the lateral crus region and nostril margin informs decisions that can affect dynamic nasal valve behavior and postoperative flaring or pinching during inspiration. Otolaryngology and plastic surgery texts often need a clean profile of the nasalis when discussing external nasal anatomy, alar base modification, and the muscular contributors to nostril shape. It also fits head and neck anatomy labs and board-style teaching where learners must localize the nasalis quickly relative to the nasal bone, mandible, and temporalis in a single frame. Anatomical accuracy verified by SciePro's Medical Advisory Board.