Dix–Hallpike test

Dix–Hallpike test is a diagnostic procedure used to identify benign paroxysmal positional vertigo (BPPV), a common cause of dizziness and vertigo. The test was named after the British neurologists Margaret Dix and Charles Skinner Hallpike who first described it in 1952.

Procedure

The Dix–Hallpike test is performed with the patient sitting upright on an examination table. The examiner turns the patient's head 45 degrees to one side and then quickly lays the patient down backwards. The patient's head is kept tilted downwards so that it hangs slightly over the edge of the table. The examiner observes the patient's eyes for nystagmus, a specific type of involuntary eye movement.

Interpretation

A positive Dix–Hallpike test is indicated by the presence of nystagmus. The direction and type of nystagmus can provide clues about the location and nature of the pathology. For example, a torsional nystagmus (where the top of the eye rotates towards the lower ear) suggests BPPV of the posterior semicircular canal.

Limitations

The Dix–Hallpike test is not suitable for all patients. It may be contraindicated in individuals with severe neck or back problems, or in those with cardiovascular conditions that could be exacerbated by the sudden changes in position.

Alternative tests

If the Dix–Hallpike test cannot be performed, alternative tests such as the supine roll test or the head-hanging test may be used. These tests can also provoke nystagmus and help identify BPPV.

Treatment

If BPPV is diagnosed, the Epley maneuver or the Semont maneuver may be performed to reposition the displaced otoconia in the inner ear, thereby relieving the symptoms of vertigo.

See also

• Vertigo
• Benign paroxysmal positional vertigo
• Nystagmus
• Epley maneuver
• Semont maneuver