Which of the following innervates the frontal sinus?

A female 44-year-old patient suffers from acute bacterial sinusitis localized to the frontal sinus. The patient displays a mucopurulent greenish discharge from the nose bilaterally, with associated fever and malaise. The patient also complains of pain over the forehead with headache.
Which of the following innervates the frontal sinus?

(A) anterior ethmoidal nerve
(B) lacrimal nerve
© nasociliary nerve
(D) posterior ethmoidal nerve
(E) supraorbital nerve


(E)The frontal sinus is innervated by the supraorbital and supratrochlear branches of the frontal nerve. All nerves mentioned in this question are branches of ophthalmic division (V1) of the trigeminal (fifth cranial) nerve. The anterior (choice A) and the posterior (choice D) ethmoidal nerves arise from the nasociliary nerve (choice C). They innervate the ethmoid and sphenopalatine sinuses. The lacrimal nerve (choice B) carries in its terminal segment the parasympathetic innervation to the lacrimal gland and provides sensory innervation to the upper eyelid.