Half Dix-Hallpike Test

The half Dix-Hallpike is a supplemental positional test classically described for suspected posterior cupulolithiasis BPPV. The standard Dix-Hallpike test remains the primary test for posterior canal BPPV, while the half Dix-Hallpike may provide additional information when findings are atypical or inconclusive (Wang et al., 2022; Kim et al., 2026).

In the standard half Dix-Hallpike, the head is turned 45° toward the side being tested and positioned approximately 30° above horizontal. This orients the posterior canal cupula approximately perpendicular to gravity, allowing a weighted cupula to be maximally deflected (von Brevern et al., 2015; Kim et al., 2026). Persistent upbeat-torsional nystagmus, with torsion toward the affected ear and lasting longer than 1 minute, supports posterior canal cupulolithiasis (von Brevern et al., 2015; Wu et al., 2024).

An augmented half Dix-Hallpike has also been described as an emerging test for suspected short-arm posterior canal canalithiasis. The patient is first held in the conventional Dix-Hallpike position and then raised into the half Dix-Hallpike position. This sequence is proposed to move short-arm otoconia toward the cupula before positioning the cupula perpendicular to gravity (Kim et al., 2026). It may be useful when the standard Dix-Hallpike produces little or no nystagmus despite findings suggestive of posterior canal BPPV (Kim et al., 2026).

The overall diagnostic sensitivity of the half Dix-Hallpike has not been established. False-negative responses can occur, meaning posterior canal cupulolithiasis may still be present even when characteristic nystagmus is not elicited; findings should therefore be interpreted with other positional tests (Wang et al., 2022; Kim et al., 2026).