Asymmetry and tuning shift of the cervical vestibular evoked myogenic potential indicate saccular dysfunction in idiopathic normal pressure hydrocephalus

Saccular functions differ for Meniere's disease with and without coexisting headaches

Objectives

To elucidate the differences between the cases of Meniere's disease (MD) with and without coexisting headaches, especially migraine. The clinical characteristics and vestibular functions are compared.

Subjects

Fifteen patients with definite unilateral MD without headaches (MD/H-; 10 males and 5 females; mean age of 55.8 years), and 20 patients with definite unilateral MD with headaches (MD/H+; 3 males and 17 females; mean age of 54.4 years; 15 cases of migraine without aura and 5 cases of suspected migraine or tension-type headache) were enrolled.

Methods

The medical records, caloric test results, and cervical vestibular evoked myogenic potential (cVEMP) of the patients were reviewed. A monothermal caloric test by injection of cold water was performed, and canal paresis was assessed. cVEMP was recorded using 500 Hz short tone bursts, and the asymmetry ratio using the corrected amplitude of p13-n23 was determined.

Results

The patients in the MD/H- group were predominantly male, whereas more female patients were seen in MD/H+ group (p = 0.004). In the MD/H+ group, the frequency of vertigo and the dizziness handicap inventory (DHI) values were significantly higher than those in the MD/H- group (p = 0.045, <0.001, respectively). There was no statistical difference in the ages, duration of illness, or the hearing levels between both groups. The caloric testing results were abnormal for 10 of the 13 MD/H- cases, and 14 of the 16 MD/H+ cases, which revealed no significant difference between both groups. The cVEMP results revealed positive saccular dysfunction based on the asymmetry ratio of 4 of the 15 MD/H- cases, and 14 of the 20 MD/H+ cases; it was significantly more prevalent in the MD/H+ group than in the MD/H- group (p = 0.018). Multivariate analysis of sex, frequency of vertigo, DHI, and cVEMP results showed significant differences only in the cVEMP results (p = 0.049).

Conclusion

The present study revealed differences in patients with MD depending on the presence or absence of headaches. MD without headaches showed a significant male preponderance. MD with coexisting headaches was more associated with severe saccular dysfunctions than MD without headaches. Concomitant headache may affect the manifestations of the vestibular function, especially in the sacculus, in MD cases.

Different results of vestibular examinations and blood flow in cases with transient vascular vertigo/dizziness with or without central nervous system symptoms

BACKGROUND

The condition of vestibular dysfunction and blood flow in the vertebral artery (VA) in transient vascular vertigo/dizziness (TVV) is not well established.

OBJECTIVES

To clarify the pathophysiology of TVV, especially the difference between the isolation of vestibular symptoms.

MATERIALS AND METHODS

Ten TVV patients with central nervous system symptoms (TVVw) and 12 TVV patients without central nervous system symptoms (TVVo) underwent duplex color-coded ultrasonographic evaluation of VAs, caloric test, and cervical vestibular-evoked myogenic potential (cVEMP).

RESULTS

The mean flow velocity (MV) ratio (peak MV of contralateral VA divided by target VA) was significantly higher in TVVw than in TVVo. There was no difference in the occurrence of canal paresis between TVVw and TVVo. Abnormal asymmetry ratios (ARs) of cVEMP were observed only in TVVo cases (6 of 12 cases), revealing a statistically significant difference in the number of cases between TVVw and TVVo.

CONCLUSIONS AND SIGNIFICANCE

Measuring VAs using duplex color-coded ultrasonography and cVEMP may help evaluate TVV. Different results of MV ratio and cVEMP between TVV cases with or without central nervous system symptoms may indicate differences in the pathophysiology between TVVw and TVVo.