Vertigo and Dizziness – Top USMLE Diseases

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.

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.