The semicircular canals work in conjunction with their partner canals on the head's contralateral side. The horizontal canal is positioned at a 30° angle from the horizontal plane, enabling it to detect movement to the left or right in the horizontal plane. The anterior and posterior canals lie in the vertical plane, designed to detect movement in the sagittal and coronal planes, respectively. The semicircular canals are arranged along 3 perpendicular planes. The hair cells are mechanically stimulated by the resistance of the endolymph, causing mechanically gated ion channels to open, subsequently triggering an action potential indicating rotational movement. The hair cells extend into the cupula, a gelatinous mass spanning the width of the ampulla.ĭuring normal rotational movement of the head, the fluid endolymph remains relatively stationary while the canals and the cupula experience motion. At the base of each canal is a bulbous expansion called the ampulla. Within the ampulla resides the crista ampullaris, a sensory receptor housing hair cells. Each semicircular canal contains endolymph. There are 3 membranous, interconnected tubes located within the temporal bone's bony labyrinth. The semicircular canals are integral components of the body's vestibular system, responsible for detecting angular or rotational movement. When properly employed, the Dix-Hallpike maneuver can confirm the diagnosis of posterior canal BPPV, enabling them to administer bedside maneuvers that often offer immediate relief to patients. It serves as the gold standard test for diagnosing BPPV. The Dix-Hallpike maneuver is a valuable tool clinicians utilize to differentiate one of the most prevalent and harmless causes of vertigo from potentially severe alternative diagnoses. These frequent recurrences can have a significant negative impact on an individual's quality of life.

Although BPPV is self-limited and can be treated with simple procedures, recurrence rates are high, with rates ranging from 36% to 50% reported in the literature. Typically, patients with BPPV experience spontaneous remission within days to weeks of symptom onset. Therefore, clinicians must perform a thorough history and physical examination to distinguish between benign and serious causes, ensuring prompt evaluation and treatment for those requiring urgent attention.īenign positional paroxysmal vertigo (BPPV) is the most common vestibular disorder globally, affecting approximately 2.4% of the general adult population over their lifetime. Most cases are mild and self-limited however, studies have shown that up to 15% of patients with vertigo presenting in the emergency department may have life-threatening underlying causes. The differential diagnosis for vertigo is broad, encompassing central and peripheral vestibular causes, cardiovascular disease, metabolic dysfunction, and medication reactions.

While it is a common complaint, evaluating a patient with vertigo can be challenging. Vertigo is a symptom characterized by a perceived sensation of motion, either of the self or the surroundings, in the absence of true motion.

Epley maneuver for vertigo at home