Inner Ear Condition (Benign Paroxysmal Positional Vertigo(BPPV))

What is Benign Paroxysmal Positional Vertigo?

BPPV is the most common cause of vertigo (80%) in patients who present in a dizzy clinic. Its pathogenesis is the displacement of otoliths from the macula of the utricle. Otoliths are calcium cabonate-containing particles that that migrate by the force of gravity towards the semicircular canals depending on the head position of the patient. The most common semicircular involved is the posterior one (95%). The aetiology can be idiopathic (50%), from infection (20%) and from head trauma (30%).

Symptoms and Signs

Typically, the patient complains of spinning vertigo when the head is placed in a particular position. Usually, this involves lying down, lifting the head looking upwards or bending down and looking upwards. The vertigo generally lasts 10 to 30 seconds. It becomes less intense with repeated manoeuvres (fatiguability). Hearing is not affected. The condition is self-limiting and resolves spontaneously in the majority of patients over a few weeks to months but can persist up to two years. It can recur, especially in the elderly.
The pathognomonic sign is seen on the Dix-Hallpike manoeuvre. This involves placing the supine patient on a couch and tilting the head backwards over the edge of the couch such that the neck is extended 30 degrees and rotated 45 degrees to one side. In this position, the ampulla of the posterior semicircular canal, which contains the end organ, is most dependent. When positive, nystagmus will be noted after a latency period of a few seconds. The nystagmus will last for up to 30 seconds and will become less noticeable with repeated manoeuvres. On sitting up, some patients demonstrate a reversal of nystagmus. This feature of reversal is not required to make the diagnosis.

Investigations

No investigations are essential but as this is an inner ear condition some routinely do an audiogram.

Management

Medications are of little benefit as the spells are episodic and short-lasting. As the condition is self-limiting, patients may experience total resolution of symptoms over time. However, in 1992, John Epley demonstrated the particle repositioning manoeuvre (PRM) which aims at returning the displaced otoliths to the utricle. The success rate is quoted at 80% after one treatment and up to 95% after repeated manoeuvres.
If conservation methods fail, occlusion of the posterior canal can be performed via a transmastoid approach with good success. It comes with a 4 to 5% risk of hearing. Fortunately, with the high success rate of PRM, surgery is rarely performed nowadays.