Clinical manifestations

Presentation and course

Otalgia may be described as burning, aching, throbbing, stabbing, lancinating, or like an electric shock. It may be mild or excruciating, but the severity of pain does not necessarily correlate with the severity of the underlying illness. It may be constant or intermittent.

Primary otalgia is often accompanied by abnormalities of the mastoid, external ear, ear canal, or tympanic membrane that are evident with inspection, palpation, and otoscopy; however, mild redness of the tympanic membrane or mild swelling of the external auditory canal are common findings and may not indicate the source of ear pain (73). Vesicles on the auricle or in the external auditory canal should suggest herpes zoster oticus (Ramsay Hunt syndrome), which may be associated with facial palsy, deafness, and vertigo; however, herpes zoster oticus should not be confused with bullous myringitis (ie, painful bullae on the tympanic membrane caused by a bacterial infection). Otalgia resulting from disorders of the middle ear and mastoid may be associated with hearing loss, a sensation of fullness, and "popping" sounds. Symptoms of Eustachian tube dysfunction include aural fullness, "popping" sounds, reduced hearing, tinnitus, autophony, otalgia, and imbalance (34). Pain in the setting of chronic otitis media or mastoiditis may be associated with multiple neurologic complications: abducens or facial palsy; labyrinthitis; sensorineural deafness; extradural, subdural, or brain abscess; meningitis; venous sinus thrombophlebitis; and otitic hydrocephalus (97; 84; 87; 48; 50). Although chronic otitis media itself is typically not painful, it may be associated with various painful complications including petrous apicitis, dural venous sinus thrombosis, and temporal lobe or cerebellar abscess (97; 87). Rarely, severe unilateral, paroxysmal, tic-like pain may involve the external auditory canal and the deep structures of the face and may be triggered by cold, noise, swallowing, or pressure on the tragus (81).

Secondary otalgia may be associated with a wide variety of abnormalities of the head and neck (70). In the presence of a normal ear on careful examination, it is important to examine the tonsils, teeth, pharynx, nose, and paranasal sinuses as possible sites of origin of otalgia (03).

Prognosis and complications

Prognosis and complications depend on the underlying condition.

Clinical vignette

Case 1. Otalgia and facial nerve palsy from middle ear lymphoma (46). A 38-year-old man with underlying diffuse large B-cell lymphoma (DLBCL) presented with acute right facial paralysis after having experienced right facial numbness for 6 months, followed by progressive right facial swelling and diplopia for 1 month and then 1 week of right facial pain, right-sided nonpulsatile tinnitus, and otalgia.

Twenty months before the current presentation, he was diagnosed with DLBCL germinal center B-cell type. He completed eight cycles of R-CHOP (rituximab, cyclophosphamide, hydroxydaunorubicin hydrochloride, vincristine, prednisone) and five cycles of R-MATRix plus (methotrexate, cytarabine, thiotepa, and rituximab).

Clinical examination revealed fullness of the right temporal region and right facial weakness reportedly sparing the forehead. In addition, there was right lateral rectus weakness with paresthesia of the right side of the face. The Rinne test was positive bilaterally, and the Weber test was central, indicating symmetrical hearing. The pinna and mastoid regions were normal. Otoscopy of the right ear was normal.

Previous CT and MRI studies taken 5 months before the onset of facial paralysis showed thickening of the right trigeminal nerve and symmetrical focal thickening of the right facial and vestibulocochlear nerves. The middle ear and mastoid were normal.

He was initially diagnosed with multiple cranial nerve palsies (polyneuritis cranialis) from chemo-related leukoencephalopathy. One month later, he developed an upper respiratory tract infection with right-sided hearing loss and severe otalgia associated with an increase in right temporal swelling involving the right mastoid region. There was no worsening of facial paralysis. Otoscopy of the right ear showed an edematous external auditory canal and a dull and bulging tympanic membrane. Pure tone audiometry revealed right moderate conductive hearing loss. He was diagnosed with a right-sided acute otitis media. However, despite initial treatment (nasal decongestants and antimicrobial ear drops), his symptoms intensified, his facial palsy worsened, and the right temporal swelling extended to involve the mastoid region. Given the progression of symptoms, intravenous ciprofloxacin was administered.

High-resolution computed tomography showed a nonenhancing soft tissue density occupying the whole right middle ear cavity, with bony erosion of the anterior wall of the right mastoid air cells. There was dehiscence of the tympanic segment of the bony facial canal. The ossicles, scutum, and tegmen tympani were intact. There was also a rim-enhancing intramuscular hypodensity within the right temporalis muscle with enhancement of the adjacent muscles. He was diagnosed with right acute otitis media, mastoiditis complicated by a right temporal abscess, and central facial palsy.

He underwent a right cortical mastoidectomy and myringotomy. Intraoperatively, the middle ear and mastoid were found to be filled with granulation tissue, which adhered to the tympanic segment of the facial nerve. The granulation tissue was removed, leaving some remaining tissue at the tympanic segment to avoid further insult and avulsion to the facial nerve. There was no pus present in the temporal region.

Histopathological examination of the mass from the right mastoid and temporalis muscle revealed DLBCL, activated B-cell subtype, with tumor cell immunoreactivity to the cluster of differentiation 20 (CD20) and MUM1. The Ki-67 proliferation index was 80%.

Postoperatively, his headache and otalgia resolved. His hearing improved, and repeat audiometry indicated mild right-sided conductive hearing loss. However, his facial palsy was worse.

Chemotherapy was begun, but the disease progressed despite completing the chemotherapy. He developed progressive right-sided hearing loss, worsening facial paresis, and increasing facial and temporal swelling indicating progression of residual disease. He refused any further intervention and ultimately died with advanced DLBCL with involvement of the central nervous system, bone marrow, right mastoid, right parotid, and right temporalis muscle.

Case 2. Otalgia and McCune-Albright syndrome (85). A 14-year-old girl with a history of recurrent otitis media presented with left otalgia and slight exophthalmos on the same side without a decrease in visual acuity. Menarche was at 7 years of age.

On examination, she was of normal height with no skeletal deformity. Several café-au-lait macules with irregular and jagged edges were evident on the body. There were no features of Cushing syndrome or acromegaly, and no galactorrhea. Thyroid examination was normal. She had a slight unilateral exophthalmos that was reducible. Visual fields were normal. The tragus of the external ear was inflamed and tender without associated otorrhea. Otoscopic examination showed narrowing of the external auditory canal; the skin of the outer portion of the external canal was shiny and erythematous, whereas the deep canal showed marked hyperemia covered with a mottled white exudate.

An audiogram demonstrated conductive hearing loss in the left ear; the air-bone gap was 35 dB. CT showed a large, extensive, homogeneous, "ground glass" appearance of the left temporal area. The superior semicircular canal was surrounded by dysplasia.

Laboratory studies showed normal serum calcium, phosphate, alkaline phosphatase, thyroid-stimulating hormone, free T4, insulin growth factor 1, and prolactin levels.

The history of precocious puberty, combined with the café-au-lait spots and fibrous dysplasia of temporal bone, established a diagnosis of McCune-Albright syndrome, a rare disease defined by the presence of at least two of the following features: polyostotic fibrous dysplasia (areas of abnormal scar-like tissue in the bones), typical café-au-lait spots, and endocrinopathies due to hormone overproduction.

Biological basis

Anatomic localization

Primary otalgia results from pathologic conditions of the ear whereas secondary otalgia results from nonotologic pathologic conditions usually in the distributions of cranial nerves V, VII, IX, or X, or the cervical plexus in the distribution of C2 and C3 (18; 41; 24).

Pathophysiology

The ear canal is heavily innervated, and the skin lining the canal lies directly against the bone without an intervening subcutaneous layer; therefore, even mild pressure, swelling, or inflammation in this area can cause immediate and severe pain (73).

The ear is supplied by a number of different sensory nerves, including cranial nerves V, VII, IX, and X, as well as the cervical plexus. Diseases affecting structures innervated by these nerves may result in referred (ie, secondary) otalgia.

The auriculotemporal branch of the mandibular division of cranial nerve V (ie, V3) innervates the skin of the tragus and part of the helix of the external ear, the anterior and superior walls of the external auditory canal, and the anterior portion of the tympanic membrane. Ear pain can also be referred via cranial nerve V from the teeth, gums, mouth, jaw, and face.

The facial nerve (VII) innervates the posterior tympanic membrane and part of the posterior wall of the external auditory canal.

The glossopharyngeal nerve (IX) innervates the posterior portion of the external auditory canal and meatus, the posterior portion of the tympanic membrane, the mastoid, and the Eustachian tube. The tympanic branch of cranial nerve IX ascends into the middle ear and forms the tympanic plexus before proceeding as the lesser petrosal nerve to the otic ganglion. Ear pain can also be referred via cranial nerve IX from the posterior tongue, tonsils, and pharynx.

The auricular branch (Arnold's nerve) of the vagus nerve (X) innervates part of the cavum conchae (the vestibule to the external auditory canal), the posterior wall of the external auditory canal, and the posterior portion of the tympanic membrane. Ear pain can also be referred via cranial nerve X from the pharynx, larynx, trachea, diaphragm, thyroid gland, and esophagus, among other thoracic and abdominal structures (10).

The upper cervical nerves (C2 and C3), particularly the posterior branch of the great auricular nerve, innervate the posterior surface of the external ear and some of the cavum conchae. Ear pain can also be referred via the cervical plexus from structures in neck and cervical spine.

Somatic afferent fibers from cranial nerves V, VII, IX, and X as well as the cervical plexus (C2 and C3) all synapse in the spinal trigeminal nucleus in the caudal medulla and the upper cervical spinal cord.

Epidemiology

In most cases of otalgia in children, the otalgia is primary, whereas less than half of the cases of otalgia in adults are primary (74; 69).

Differential diagnosis

Associated or underlying disorders

Most cases of primary otalgia are not neurologic. Referred otalgia is common, but diagnosis may be difficult given the vast range of potential etiologies that can be referred through the extensive sensory innervation of the ear (02). The most common cause in children is otitis media, but various infectious, inflammatory, traumatic, and malignant conditions of the external and middle ear can cause otalgia in both children and adults (73; 74; 97; 98; 37; 96; 84; 27; 58; 69; 01; 82; 35). Otitic barotraumas and barotalgia are common among air travelers but can also occur with scuba diving and with exposure to various explosions (45; 86; 65; 16). Rare causes of primary otalgia include Gradenigo syndrome (97; 50), neuralgias of the intermediate nerve (nerve of Wrisberg; nervus intermedius), geniculate ganglion, or the tympanic branch of the glossopharyngeal nerve (78; 21; 100; 74; 81; 59; 43; 80), 12th nerve neurilemmoma occurring the middle ear (91), and aberrant carotid artery in the middle ear (83). Other non-neurologic causes of primary otalgia include acute otitis externa (“swimmer’s ear”), a carbuncle or furuncle (folliculitis) of the external auditory canal, foreign bodies in the external auditory canal, bullous myringitis (a viral infection of the tympanic membrane), malignant external otitis (a necrotizing, potentially fatal, pseudomonas infection of the skull base affecting immunosuppressed individuals and diabetics), keratosis obturans (accumulation of desquamated keratin in the external auditory canal), cholesteatoma, squamous cell and other malignancies, mastoiditis, and chronic serous otitis media associated with Eustachian tube dysfunction (97).

Even when otalgia is primary and not directly associated with neurologic dysfunction, there may be associated or secondary neurologic dysfunction (19; 87; 92).

Secondary otalgia may be caused by a wide variety of inflammatory, infectious, neoplastic, musculoskeletal, and vascular disorders of the head and neck, including disorders of the paranasal sinuses and nasal cavity, nasopharynx and retropharynx, the oropharynx and oral cavity (eg, peritonsillar abscess or “quinsy tonsil”), teeth (eg, dental infection, malocclusion, impacted teeth, erupting teeth, and bruxism), the temporomandibular joint, the parotid gland (eg, mumps parotitis, bacterial parotitis, or parotid neoplasm), hypopharynx and larynx (eg, carcinoma as well as rheumatoid arthritis or ankylosing spondylitis involving the cricoarytenoid joint), the thyroid gland, the esophagus, the lungs, and the neck and cervical spine (74; 97; 88; 94; 55; 29; 17; 30; 44; 54; 69; 75; 35; 51; 63). Referred dental pain, temporomandibular joint pain (Costen syndrome), and cervical spine pain are among the most commonly reported causes of secondary otalgia (23; 04; 12; 14; 15; 56; 55; 94; 17; 30; 44; 35; 61; 02). Pain from dental infections of the molars, especially mandibular molars, can radiate to the ear (97; 35). Bruxism (teeth clenching) often (but not universally) produces bilateral otalgia, often with evidence of excessive wear on the incisal edges of molar teeth, whereas most other causes produce unilateral otalgia (97; 51). Otalgia can be a presenting complaint in patients with nasopharyngeal carcinoma (77; 99; 62; 17; 35). Otalgia may also occur with cervical diffuse idiopathic skeletal hyperostosis (DISH), although dysphagia is a more common symptom; other symptoms can include sleep apnea, pharyngeal globus, coughing, dysphonia, dyspnea, and various neurologic findings from medullary compression (29; 75). Rare causes of secondary otalgia include Eagle syndrome (28; 22; 06; 88; 64; 26; 47; 35; 89), stylohyoid ligament calcification (particularly in Turner syndrome) (66), infections or malignancies of the temporal bone (39; 57; 01; 82), intrapetrous carotid artery aneurysms (07), and C1 myelitis (63). Eagle syndrome results from an elongated styloid process and is associated with referred otalgia, recurrent throat pain, pharyngeal foreign-body sensation, dysphagia, cervicofacial pain, tinnitus, and in some cases impingement of the external or internal carotid artery with carotidynia (97; 08; 64; 26; 47; 35; 89).

Neurologic disorders causing secondary otalgia include migraine (90); trigeminal neuralgia (typically a facial pain, but pain can also radiate to the ear) (97); trigeminal neurinomas (68); malignant trigeminal schwannoma (49); Slude (sphenopalatine) neuralgia (typically with ear and nasal pain with radiation to the ear) (97); Bell palsy (38); herpes zoster oticus (Ramsay Hunt syndrome) (42; 71; 67; 93; 60; 52; 20; 38); intermedius, glossopharyngeal, and vagus neuralgias (81; 72); Herpes simplex virus infection of the vagus nerve (05); chronic paroxysmal hemicrania (11); idiopathic intracranial hypertension (79); whiplash injury, cervical radiculopathy, and arthritis (56); C1 myelitis (63); carotidynia; and myofascial pain syndromes. Otalgia in conjunction with headaches, subacute sensorineural hearing loss with subjective tinnitus, and vertigo has been reported due to idiopathic intracranial hypertension (79). Severe, persistent, and refractory otalgia having features of neuropathic pain (ie, burning character and allodynia) in conjunction with both facial weakness and hemifacial spasm, sometimes with a polyphasic course and sometimes responding to intravenous immunoglobulin therapy, has been reported with rheumatological conditions (eg, Sjögren syndrome or rheumatoid arthritis) (09). Note that some authors consider otalgia associated with these neuralgias to be primary otalgia, whereas most consider them as referred (secondary) otalgias (97). Otalgia is also often associated with stress (56) and may be psychogenic (25).

Fenton and colleagues have proposed the “13 Ts” of nonneurologic referred otalgia as an expansion of a prior list of “10 Ts” of referred otalgia by Harvey (36; 31). Most adult-referred otalgia is caused by mechanical disorders of neck and jaw (66%), whereas disorders of the teeth contribute only 6%, and sinister pathologies contribute 5% (31). This list is only a guide to facilitate clinical evaluation for potential causes of otalgia, and some conditions could reasonably be placed in more than one of the listed “Ts.”

Table 1. The “13 Ts” of Referred Otalgia

Diagnostic workup

Red flags that require a careful and detailed assessment include the following: (1) neurologic symptoms, particularly those referable to cranial nerves V, VII, IX, and X; (2) associated oropharyngeal symptoms (eg, dysphagia, dysphonia, odynophagia, hemoptysis, weight loss, smoking history), which warrant consideration of head and neck cancer; (3) progressive or sudden-onset hearing loss; (4) visual symptoms (loss of vision, scotomata); (5) immunosuppression or diabetes, which may allow an infection to progress (35).

When the ear is the source of pain (ie, primary otalgia), the ear examination is typically abnormal, but when the ear is not the source of pain (ie, secondary otalgia), the ear examination is usually normal. The cause of secondary otalgia may be difficult to identify because of the complex innervation of the ear and the many potential sources of referred pain (30; 69). Patients with unilateral otalgia who are older than 50 years and who smoke, drink alcohol, or have diabetes are more likely to have a serious occult cause of ear pain (30).

A careful examination of the auricle, external auditory meatus and canal, and the tympanic membrane is necessary to exclude ear pathology as a cause of otalgia. Pain with manual pressure on the tragus suggests inflammation of the external auditory canal, usually from external otitis media (swimmer's ear). In some cases, careful palpation of the bony and cartilaginous portions of the external auditory canal and meatus with a tightly wound cotton-tipped applicator may be necessary to localize pain with suspected (but not grossly evident) early neoplasm of the external canal (74). Otoscopy will allow identification of abnormalities of the external auditory canal tympanic membrane or middle ear, including cholesteatoma. Tympanometry can aid in detecting Eustachian tube disorders, alterations in middle ear pressure, and fluid in the middle ear. Audiograms can be helpful in identifying and characterizing associated hearing loss.

If no ear disease is identified, secondary otalgia is likely, but unfortunately, no simple diagnostic algorithm is available. A careful history and examination of the entire head and neck is necessary to exclude pathologic conditions causing referred or secondary otalgia. In particular, unilateral otalgia in an adult patient without otologic findings warrants thorough assessment to exclude head and neck carcinoma, especially if identified risk factors (eg, smoking, alcohol use, previous carcinoma), suggestive symptoms (eg, hoarseness, weight loss, dysphagia, odynophagia, progressive nasal obstruction), or signs are present (eg, persistent middle ear effusion, neck mass, epistaxis) (73; 74; 99; 62; 17; 69). Symptoms that should be specifically identified in patients with secondary otalgia include neck pain, bruxism, toothache, jaw pain, pain with chewing or jaw opening, dysphagia, odynophagia, burning in the throat with acidic foods, hoarseness, dyspnea, recent weight loss, anorexia, malaise, night sweats, fever, or chills. Examination should include structures innervated by cranial nerves V, VII, IX, and X as well as the upper cervical nerves. The teeth should be examined for obvious caries, malocclusion, missing molars, poorly fitting dental prostheses, and wear facets on the canines (the latter being evidence of bruxism). The teeth should be individually palpated with a probe or tongue blade. The temporomandibular joints should be palpated with the mouth both closed and widely open. Palpation of an elongated styloid process in the back of the throat may be possible in patients with Eagle syndrome (64).

X-rays of the paranasal sinuses, cervical spine, skull, and chest; barium swallow; endoscopy; indirect laryngoscopy; fiberoptic nasopharyngoscopy; computerized tomography or magnetic resonance imaging of the skull base and neck; and conventional or magnetic resonance angiography are additional studies that can be considered in select patients. Biopsy should be performed for suspicious lesions of the auricles, external auditory canal, or oropharyngeal cavity. If examination and diagnostic studies are unrevealing, patients should be periodically reexamined.

Diagnostic anesthetic blocks and pharyngeal cocainization can be helpful in localizing the site of referred otalgia (eg, to an abscessed tooth, to the temporomandibular joint, to the tonsillar area, etc.). Pain triggered by swallowing and radiating to the throat, which is temporarily resolved with pharyngeal cocainization, is strongly indicative of glossopharyngeal neuralgia (81). Anesthetic blocks of the external auditory canal or the tympanic cavity provide relatively limited information because of the nerve overlap in these areas (81). Intraoperative nerve stimulation under regional anesthesia has also been reported to be helpful in identifying the responsible nerve in cases of neuralgia, although this is not universally accepted (81).

Referral to an oral surgeon is appropriate if dental or temporomandibular joint pathology is suspected as the cause of secondary otalgia; an anesthetic nerve block can be used diagnostically to transiently relieve the otalgia. Referral to an otolaryngologist is appropriate if suspected primary otalgia fails to respond to usual therapy, if head and neck cancer is suspected (eg, identified lesion, progressive unilateral otalgia in a smoker or drinker, etc.), or if no cause is identified with careful evaluation. Referral to a neurosurgeon is appropriate if medical management of neuralgias is unsuccessful.

Management

Management depends on the underlying pathology. Review of the management of nonneurologic conditions causing otalgia is beyond the scope of this chapter, but a number of excellent reviews are available (73; 74). A few neurologic conditions will be specifically discussed.

Rarely, aural foreign bodies may be associated with the development of mastoiditis and meningitis, including those placed iatrogenically (eg, ear wick for treatment of external otitis) (13).

Otalgia associated with Eagle syndrome may be treated surgically with resection of the styloid process by either a trans-oral or extraoral-cervical approach (64).

Otalgia associated with migraine typically responds to migraine therapy with improved symptom frequency, severity, and duration (90).

Otalgia associated with chronic paroxysmal hemicrania can respond dramatically to indomethacin (11).

Ramsay Hunt syndrome should be treated with acyclovir (42; 71; 67; 53; 93); associated otalgia often improves rapidly (42), although patients may have persistent facial paresis and deafness (40; 53).

In the absence of evident observable pathology, neuralgic otalgia is treated with analgesics and anticonvulsants (eg, carbamazepine, phenytoin, gabapentin).

Surgical treatment of idiopathic otalgia should be reserved for patients in whom medical treatment has failed (95). In cases of otalgia with trigeminal, intermedius, glossopharyngeal, or vagal neuralgia that do not respond to medical management, consideration can be given to nerve section, neurolysis, or microvascular decompression (78; 21; 100; 81; 72; 59; 76; 32), but many of these procedures have significant failure rates and may be associated with significant morbidity (81; 59). In patients with intractable geniculate neuralgia, excision of the nervous intermedius and geniculate ganglion can be a definitive treatment and can be performed without causing facial paralysis (76). If the origin of the otalgia is found to be the sensory auricular branch of the facial nerve, the section of this nerve offers favorable outcomes with no morbidity (95). An anecdotal report suggests benefit of high cervical spinal cord stimulation for chronic otalgia and tinnitus (33).