Head shaking during Dix-Hallpike exam increases the diagnostic yield of posterior semicircular canal BPPV.

OBJECTIVES: To examine whether shaking the head during the DH exam (HSDH) may improve diagnosis of posterior semicircular canal benign paroxysmal positional vertigo (pBPPV) in patients with a negative Dix-Hallpike (DH) examination.

STUDY DESIGN: A prospective cohort clinical study on consecutive patients with dizziness, who were seen by 2 experienced neurotologists. Patients underwent a complete neurotology examination, including positioning testing with roll test and DH. Patients with a negative DH underwent a HSDH. Patients with a positive DH (Group 1) or only with a positive HSDH (Group 2) underwent a particle reposition maneuver (PRM), which was a modification of the Epley maneuver. Variables including sex, age, the duration of symptoms until diagnosis, and the number of visits required until cure were examined in each group.

SETTING: A tertiary dizziness clinic and in 2 private clinics.

SUBJECTS AND METHODS: All patients diagnosed with pBPPV.

MAIN OUTCOME MEASURES: DH test after head shaking and comparison of variables between the 2 study groups.

RESULTS: Sixty nine patients were diagnosed with pBPPV (Group 1). Twelve additional patients were negative on DH but were found positive on HSDH (Group 2), improving the diagnostic yield by 14.8%. There was no statistical relation between the 2 groups and the variables examined; however, there was a trend for longer duration of symptoms (44.3 versus 64 d) and less visits until cure (1.5 versus 1.7 visits) in Group 2.

CONCLUSION: Patients with a negative DH should undergo a HSDH. Patients only diagnosed as pBPPV by a positive HSDH may represent a subgroup with a milder form of disease.