Can Postural Instability Respond to Galvanic Vestibular Stimulation in Patients with Parkinson’s Disease?

Abstract

ObjectiveGalvanic vestibular stimulation (GVS) activates the vestibular afferents, and these changes in vestibular input exert a strong influence on the subject’s posture or standing balance. In patients with Parkinson’s disease (PD), vestibular dysfunction might contribute to postural instability and gait disorders.MethodsCurrent intensity was increased to 0.7 mA, and the current was applied to the patients for 20 minutes. To perform a sham stimulation, the current intensity was increased as described and then decreased to 0 mA over the course of 10 seconds. The patient’s status was recorded continuously for 20 minutes with the patient in the supine position.ResultsThree out of 5 patients diagnosed with PD with postural instability and/or abnormal axial posture showed a reduction in postural instability after GVS. The score for item 12 of the revised Unified Parkinson’s Disease Rating Scale part 3 was decreased in these patients.ConclusionsThe mechanism of postural instability is complex and not completely understood. In 2 out of the 5 patients, postural instability was not changed in response to GVS. Nonetheless, the GVS-induced change in postural instability for 3 patients in our study suggests that GVS might be a therapeutic option for postural instability.

Vestibular neuromodulation: stimulating the neural crossroads of psychiatric illness

“…This is beginning to occur in neurological contexts, such as daily right‐ear CVS for four weeks improving aphasic syndrome in left‐hemisphere stroke and disturbed arm position sense in poststroke neglect improving with galvanic vestibular stimulation (GVS) relative to sham stimulation (note that GVS does not appear to activate ACC) . There are also reports of GVS relative to sham GVS improving autonomic, motor and other functions in Parkinson’s Disease and other central neurodegenerative disorders, and early evidence that repeated CVS for several weeks can induce behavioural improvement in the minimally conscious state . Moreover, following reports of persistent pain and allodynia modulation by CVS in case studies and small case series (discussed in Miller and Ngo 3 ; see also McGeoch et al), a recent study examined 34 subjects with persistent (mostly neuropathic) pain and found that (i) a single session of right‐ear CVS induced small but statistically significant short term modulations of pain relative to a forehead icepack cold‐arousal control condition, (ii) three of nine subjects with allodynia had large, clinically significant CVS modulations, and (iii) CVS was well tolerated, with only one subject experiencing vomiting.…”

Aplicações dos potenciais evocados miogênicos vestibulares: revisão sistemática de literatura

“…The studies about VEMP with auditory stimulation have evidenced this test as an assisting tool for the diagnosis of several types of peripheral vestibular disorders, predominantly Meniere's disease (5,6,29,40) and superior semicircular canal dehiscence (SSCD) (8)(9)(10)(11)32) , as well as diseases related to central vestibular disorders, such as motor myelopathies (19)(20)(21)(22)(23)(24)(25) and Parkinson's disease (15,(41)(42)(43) .…”

The Effect of L-dopa on Postural Stability in Parkinson’s Disease Patients

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