Transverse part of nasalis muscle

The transverse part of nasalis muscle, also known as the compressor naris, is the superior portion of the nasalis muscle. It functions primarily to compress the nasal aperture, thereby narrowing the nostrils.

Anatomical details

1. Origin

From the maxilla, above and lateral to the incisive fossa.

2. Course

Its fibres pass upward and medially, forming a thin aponeurosis across the bridge of the nose.

3. Insertion

The aponeurosis blends with:

• The contralateral transverse part of the nasalis, and

• The aponeurosis of the procerus muscle.

Innervation

Facial nerve (cranial nerve VII) — via its buccal branch.

Blood Supply

Facial artery, a branch of the external carotid artery.

Actions

The transverse part of nasalis muscle compresses the nasal aperture, narrowing the nostrils and drawing the skin of the nose downward and medially. Thereby, assisting in regulating nasal airflow and contributing to facial expressions involving the nose.