BENIGN PAROXSYMAL POSITIONAL VERTIGO (BPPV)

BPPV is felt to be the most common type of vertigo. This disorder can be seen following head injury, vestibular neuronitis, stapes surgery, Meniere’s disease, or present alone. The disorder is felt to be related to an abnormality in the association of the otoconia to the cupula within the membranous labyrinth resulting in abnormal responses to endolymphatic movement with head motion. Symptoms are typically associated therefore with head movement such as rolling over or getting in or out of bed. The associated vertigo is brief, lasting only seconds in duration.

VESTIBULAR NEURONITIS

This condition presents as a sudden episode of vertigo without hearing loss in an otherwise healthy person. The disorder can occur as a single attack or can present as multiple attacks. It occurs more often in spring and early summer and, as a result, is often associated with an upper respiratory infection, developing two to three weeks afterward. The onset o f vertigo is sudden and is typically associated with nausea and vomiting and can last for a period of days with gradual improvement over the following weeks. The disorder is often followed by episodes of benign positional vertigo.

LABYRINTHITIS

Labyrinthitis is an inflammatory process occurring within the membranous labyrinth that may have a bacterial or viral etiology. Viral infections produce symptoms of dizziness similar to vestibular neuronitis, except that there is cochlear dysfunction as well. (Hearing Loss)

LABYRINTHINE INFARCTION

This event leads to a sudden profound loss in auditory and vestibular function and typically occurs in older patients. This phenomenon can be seen in younger patients with atheroscelortic vascular disease or hypercoagulation disorders. Episodic vertigo may herald a complete occlusion in the form of a type of transient ischemic attack. After complete occlusion, the acute vertigo that ensues will subside often leaving the patient with some residual unsteadiness and disequilibrium over the next several months while vestibular compensation occurs.

MENIERES'S DISEASE

This is an inner ear disorder characterized by episodic vertigo attacks, sensorineural hearing loss, tinnitus, and pressure or fullness in the involved ear. Initially, the hearing loss involves the lower frequencies and fluctuates, usually worsening with each attack. The attacks are characterized by true vertigo, usually with nausea and vomiting lasting hours in duration. Histopathologically, this disorder is felt to be due to dilation of the endolymphatic spaces with ruptures and healing of the membranous labyrinth. Variants of the disease do occur.

MIGRAINE ASSOCIATED VERTIGO

The vast majority of migraine variants are made up of the first two categories, migraine without aura, and migraine with aura. The term aura can be defined as a focal neurological disorder. Auras generally are considered to be abnormal sensory perceptions. Visual auras are the most frequent type, and may come in a wide variety of phenomena or hallucinations.

It is valuable for healthcare professionals to have at least a basic understanding of migraine and audiovestibular symptoms. Vertigo, tinnitus, photophobia, and phonophobia, and occasionally hearing loss may present in at least 30% of migraine patients.

Although hearing loss in migraine patients is less common than in vertigo, tinnitus, photophobia, and phonophobia, it may present as a low frequency fluctuating sensorineural hearing loss. It is possible, however, to have a permanent hearing loss or vestibulopathy (as indicated by caloric weakness) secondary to a migraine attack. The commonality of these symptoms, often make it difficult to distinguish the disorders on clinical grounds alone.

This collection of symptoms may first be thought as consistent with Meniere's disease, or other types of inner ear involvement, such as a recurrent vestibular neuronitis, particularly in patients with recurring episodes or attacks. The differential diagnosis of migraine and Meniere's disease, then, may often present as a diagnostic enigma. In addition, 60% will report a lifelong history of motion sensitivity. Interestingly, the incidence of Meniere's disease is twice as prevalent in migraineurs, as in the general population.

ACOUSTIC NEUROMA

This is also called a vestibular neurinoma, which is a benign neoplasm that typically arises from the vestibular portion of the eighth cranial nerve. The lesion grows slowly and causes a progressive sensorineural hearing loss. Because of the gradual destruction of vestibular function on the involved side, patients do not typically present with complaints of dizziness.