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[The false-negative reasons of positioning test in benign paroxysmal positional vertigo].

OBJECTIVE
To analyze the false-negative proportion and reasons of positioning test in benign paroxysmal positional vertigo (BPPV).


METHOD
Sixty-eight cases were reviewed and analyzed during February to April 2009. All patients had typical clinical history of BPPV and diagnosed by positioning test,and all were treated with PRM successfully. If positioning test at the first time were negative, examinations repeated after either head shaking or return visits.


RESULT
Thirteen patients (19.12%) appeared false-negative in positoning test, and 11 cases showed typical nystagmus after head shaking,while 2 cases were diagnosed by return visitis the next day. There were no statistically difference between false-negative group and positive group in age (P > 0.05), gender (P > 0.05), course of disease (P > 0.05) and types of semi-circular canal (P > 0.05).


CONCLUSION
Re-examinations after head shaking or return visits are useful for the diagnosis in the suspected BPPV patients who have negative positioning test.