Vertigo, Dizziness, and Disorders of Balance

The cerebellum, Latin for "little brain", is located in the posterior cranial fossa, dorsal to the pons and midbrain, and its principal role is in the coordination of movements. The cerebellum consists of 3 lobes on either side of its 2 hemispheres and is connected in the middle by the vermis. Three paired peduncles link the cerebellum to the brainstem and diencephalon. Much like the cerebral cortex, the cerebellum has a cortex of gray matter on the surface.

The auditory and vestibular pathways are anatomically related but discrete pathways that permit conscious perception of and reaction to sound and spatial orientation. Stimulation of specialized hair cells in the cochlea and vestibular apparatus excite and send signals through partitions of the vestibulocochlear nerve (CN VIII) to the brainstem, where they synapse on various targets, send and receive other projections, and ultimately contribute to spatial orientation and perception of sound.

Cerebellar disorders are a specific set of neurologic signs and symptoms caused by local or systemic conditions that affect the cerebellum; the classic sign is ataxia, in addition to several other motor abnormalities that affect coordination. The causes of cerebellar disorders range from acute alcohol intoxication to inherited conditions. Clinical presentation is with incoordination of voluntary muscle movement, affected ocular movements, speech, gait, balance, and muscle tone. The diagnosis is initially made clinically and then followed by imaging studies to determine the etiology; management depends on the specific etiology.

Vertigo is defined as the perceived sensation of rotational motion while remaining still. A very common complaint in primary care and the ER, vertigo is more frequently experienced by women and its prevalence increases with age. Vertigo is classified into peripheral or central based on its etiology. Vertigo is a clinical diagnosis, differentiated through history and physical examination findings, most notably nystagmus. Further testing may be required in malignant cases. Management depends on the etiology but certain maneuvers such as the Epley maneuver can be diagnostic and therapeutic.

Syncope is a short-term loss of consciousness and loss of postural stability followed by spontaneous return of consciousness to the previous neurologic baseline without the need for resuscitation. The condition is caused by transient interruption of cerebral blood flow that may be benign or related to a underlying life-threatening condition. Syncope is not a distinct disease entity; rather, it is a symptom of another pathologic process, whether it be transient or a more established disease process. Syncope may be accompanied by other symptoms, such as light-headedness, sweating, palpitations, nausea, feeling warm or cold, and visual blurring. Workup includes a detailed history and physical examination, electrocardiography, echocardiography, provocative testing (tilt-table test), or imaging of the suspected culprit vasculature. In many cases, a definite etiology is not found. Management is based on the underlying cause and can include physical countermaneuvers, stopping offending drugs, volume resuscitation, blood transfusion, and/or cardiac or vascular interventions.

Alcohol is one of the most commonly used addictive substances in the world. Alcohol use disorder (AUD) is defined as pathologic consumption of alcohol leading to impaired daily functioning. Acute alcohol intoxication presents with impairment in speech and motor functions and can be managed in most cases with supportive care. Withdrawal from chronic alcohol use can have fatal consequences, including delirium and seizures, and is managed with benzodiazepines. Chronic AUD affects almost every part of the human body and has serious impacts on a person’s mental and physical health. Alcohol user disorder can be managed with psychotherapy as well as medications; however, the prognosis is usually poor, with high rates of relapse and complications.