Nervus Intermedius Neuralgia

Abstract

Purpose of review: This review discusses the diagnosis and treatment of nervus intermedius neuralgia (NIN) and identifies gaps in the literature.

Recent findings: The nervus intermedius is a branch of the facial nerve. NIN presents as a rare neuralgia of this nerve, causing deep ear pain, which may radiate to the auditory canal, auricle, mastoid, soft palate, temple, and angle of the jaw. NIN most commonly presents in middle-aged women; neurovascular compression involving the anterior inferior cerebellar artery is the most common etiology described. Despite its diagnostic criteria in the International Classification of Headache Disorders, 3rd edition (ICHD-3), NIN may lack a trigger zone and may manifest as achy or neuralgiform pain instead of the typically described sharp or shooting pain. Like trigeminal neuralgia, NIN can be divided into classic, idiopathic, secondary, or painful neuropathy. Although there are no established guidelines for treating NIN, many possible treatments are used. Experience from treating trigeminal neuralgia suggests that carbamazepine or oxcarbazepine can be considered first-line. Patients with medically refractory NIN may benefit from neurosurgery referral for microvascular decompression or nerve sectioning. More research is needed to elucidate the range of clinical presentations in patients with NIN. Current data are limited and suggest that symptoms may diverge from the ICHD-3 diagnostic criteria. Although various treatments have been attempted, they often lack solid evidence and are typically derived from approaches used for other neuralgias. Proper diagnosis is crucial, particularly when considering surgical referral, due to the potential overlap of NIN with other neuralgias affecting the head and neck.

Keywords: Auditory canal; Ear; Facial nerve; Headache; Neurovascular compression; Pain.