The ophthalmic division supplies part of the mucous membrane of which areas?

• A. Nose and paranasal sinuses
• B. Oral cavity
• C. Larynx
• D. Esophagus

Answer: (A)

The ophthalmic division (V1) is the first branch of the trigeminal nerve and supplies sensory fibers to the orbit and nearby structures, including the mucous membranes of the nasal cavity and paranasal sinuses. Its nasal branches, such as the anterior and posterior ethmoidal nerves, convey sensation from these mucosal surfaces, which is why this division contributes to the nasal and sinus mucosa. The oral cavity mucosa is mainly served by the maxillary division (V2), while the larynx and esophagus receive innervation from the vagus nerve (cranial nerve X). So the areas that receive mucous membrane innervation from the ophthalmic division are the nose and paranasal sinuses.