Primary Otalgia
Pinna
Primary pinna pain in the first instance may be caused by injuries or traumas that may result in laceration, burns, frostbite, infections, or abscesses. In the case of persistent minor lesions, a biopsy should be performed, because these lesions may obscure a malignant new growth, especially a basal cell carcinoma, a squamous cell carcinoma, or small benign growths.
External Ear Canal
The external ear canal is a particularly common source of primary earache. External otitis arises from an acute inflammatory process after ear trauma, inadequate cleansing of the external ear canal, or lengthy contact with liquid in bacterially contaminated water, especially in bathing lakes or swimming pools (swimmer’s ear). External otitis, however, may occur on the basis of a chronic middle ear infection or as a result of a malignant new growth in the external ear canal. Malignant external otitis may be observed, particularly in patients with diabetes mellitus or an immune deficiency. In addition to severe earache with reddening of the pinna and inflammation of the periauricular region, there is heightened sensitivity to touch, swelling of the pinna, and swelling of the mastoidale. A general feeling of malaise and elevated temperature also may occur.
Ear wax also may be responsible for earache and pressure in the ear. The same applies to foreign bodies in the ear canal. Removal of such objects must be undertaken with the utmost care and precision to avoid injuring the external ear canal and the tympanic membrane. Another cause of earache may be benign or malignant new growth in the external ear canal. In case of doubt, a biopsy should be performed. Neoplasms are rare and in most cases take the form of a squamous cell carcinoma or adenocarcinoma.
Middle Ear and Mastoid
An acute infection of the mucous membrane of the middle ear in the form of acute otitis media usually stems from an infection of the upper air passages with dysfunction of the eustachian tube. Rhinitis and adenoid inflammation also may cause acute otitis media. The disease usually is accompanied by an elevated temperature and infection of the upper respiratory tract. Examination reveals reddening and swelling of the tympanic membrane. Occasionally, a purulent discharge is present.
Acute mastoiditis may complicate otitis media if not treated properly. Typically, a highly sensitive and swollen mastoidale is present. Obstruction of the pinna, a reddened and bulging tympanic membrane, and purulent otorrhea are typical examination findings. An initial slight ache increases sharply with the purulent inflammation and radiates into the entire neck and head area.
Petrositis
Inflammatory spread to the petrous bone from otitis can occur and would be complicated by meningitis or an intracranial or extradural abscess. Pain can be referred to the temporoparietal, retro-orbital, and temporal regions. Lesions of the cranial nerves also may be observed. The
classic triad of findings associated with lesions of the petrous apex (Gradenigo syndrome) includes (
1) deep retro-orbital pain, (
2) paresis of the ipsilateral lateral rectus muscle, and (
3) otorrhea.
Acoustic Neuroma
Acoustic neuroma (vestibular schwannoma) is a benign tumor of the neural sheath of the eighth cranial nerve and its peak incidence is mostly between the ages of 30 and 40. Women are affected more frequently than men. Tinnitus, hearing loss, and tingling or deep pain in the ear are early symptoms. Over time, these symptoms may be joined by vertigo. As the tumor slowly grows out of the internal auditory canal into the cerebellopontine angle it can compress the fifth and seventh cranial nerves, producing numbness and weakness of the face. Dysarthria, ataxia, and incoordination also may be observed due to compression of the adjacent cerebellum. Obstruction of cerebrospinal fluid circulation may give rise to headache from increased intracranial pressure with nausea, vomiting, and neuropsychologic deficits.
Traumas
Trauma of the tympanic membrane may be caused by direct mechanical damage with fracture of the temporal bone or by external compression. Foreign bodies also may give rise to traumatic perforation of the tympanic membrane. Rupture of the tympanic membrane also may occur as a result of increased pressure in the external ear canal, for example, as a result of a slap on the ear with an open hand. Earache and hearing loss occur as typical symptoms.
Barotrauma is caused by elevated pressure in the external ear canal, for example, by sudden changes of pressure in an airplane or during diving activities. Symptoms include localized or radiating pain in the region of the middle ear but also along the fifth, ninth, and tenth cranial nerves. Hematotympanum and conduction deafness also may occur.
Trauma of the temporal bone most commonly leads to a longitudinal fracture, which may result in rupture of the tympanic membrane. Depending on its course, the fracture may lead to paralysis of the seventh cranial nerve. Pain radiates into the area of distribution of the fifth, ninth, and tenth cranial nerves. In addition, conduction deafness or facial paralysis may be observed. Given appropriate localization, drainage of cerebrospinal fluid or blood from the external ear canal also may occur. An ecchymosis over the mastoid (Battle sign) is an indication of a fracture of the base of the skull.
In a transverse fracture, there may be no rupture of the tympanic membrane, depending on the course of the fracture line. If the internal auditory canal is involved, lesions of the seventh and eighth cranial nerves may occur with sensory-neural hearing loss, vertigo, and facial paralysis.
Benign and Malignant New Growth in the Middle Ear
A growth in the middle ear is rare but always should be considered if a chronic middle ear infection or a polypoid lesion does not respond to adequate treatment and chronic pain continues. The pain is typically localized, but it may radiate into the areas of distribution of the fifth, ninth, and tenth cranial nerves. Examination reveals local ulceration, which should be subjected to biopsy.