Clinical picture of vestibulotoxicity with drugs includes imbalance and babbingoscillopsia. Nistagmus is not seen and thermal and rotational tests show bilateral dysfunction of labyrinths. Aminoglycosides are the main category causes inner ear toxicity more than any other antibiotics.The amount of degeneration of vestibular system depends on the type of drug, repetition and total dose age.

Background and Aim: Patients with migraine commonly show vestibular symptoms. However, abnormal neurotological test findings during the inter-attack intervals, even in the absence of vestibular symptoms, are suggestive of subclinical vestibular dysfunction in migraine. This study aimed to compare the vestibular evoked myogenic potentials between migraine patients and normal individuals.
Methods: Subjects included 25 patients with migraine and 26 healthy volunteers with an age range of 20-53 years old. The vestibular evoked myogenic potentials were recorded with 500 Hz tone bursts at 95 dB nHL.
Results: Mean of absolute amplitude and p13 latency values in the migraine group were significantly less and more than the normal group, respectively (p=0.001 for absolute amplitude in right and left ears p=0.004 for p13 latency in right ears and p=0.02 in left ears). There was no statistically significant difference between the two groups in mean of the n23 latency and also the amplitude ratio (p>0.05).
Conclusion: According to the prolonged latency of vestibular evoked myogenic potentials response, vestibulospinal tract in brainstem is probably involved in migraine patients. However, due to small sample size, for generalizing this result to all patients with migraine, further researches are needed.

Background and Aim: In many migraine patients prophylactic drugs are effective in reducing attacks and symptoms such as vestibular complaints. Therefore, related neural pathways are probably also affected. This study aimed to compare vestibular evoked myogenic potential in migraine patients under treatment with prophylactic drugs and those without any treatment.
Methods: Subjects included 46 patients with migraine. They were evaluated in two groups those under treatment with prophylactic drugs (21 subjects) and those without treatment (25 subjects). The age range of patients was 20-60 years. The vestibular evoked myogenic potential were recorded with 500 Hz tone bursts at 95 dB nHL.
Results: Mean of amplitude ratio (p=0.02), and interpeak latency values in the right ear (p=0.03) and left ear (p=0.001) were higher in patients with prophylactic therapy than the group without therapy this difference was statistically significant. There was no statistical difference between the two groups in terms of mean of latency of p13 and n23 peaks, and absolute amplitude (p>0.05).
Conclusion: Prophylactic drugs probably improve mean of main response parameters of vestibular evoked myogenic potential in migraine patients with prophylactic therapy.

Background and Aim: Patients with type I diabetes mellitus commonly complain about dizziness, floating sensation, tinnitus, weakness, and sweating. The aim of this study was comparing vestibular evoked myogenic potentials (VEMPs) between these patients and normal people.

Methods: Twenty-four patients with type I diabetes mellitus and twenty-four healthy volunteers with the age range of 15-40 years were enrolled in this study. A tone burst of 500 Hz, with the intensity of 95 dB nHL, was delivered through a insert earphone and vestibular evoked myogenic potential was recorded. The t-test was used to compare the results between the two groups. To investigate the effect of glycated hemoglobin (HbA1c) on VEMP responses (latency, absolute and relative amplitude), the regression analysis was used.

Results: The mean p13 and n23 latency were significantly more in patients with type Ι diabetes mellitus (for P13 latency, p=0.013 in right and p=0.010 in left ear, and for n23 latency, p<0.001 in right and p=0.005 in left ear). There was no significant difference between two groups in absolute and relative amplitude and prevalence of the VEMP (p>0.050). There was no correlation between VEMPs and HbA1c in patients with type 1 diabetes mellitus (p>0.05).

Conclusion: Prolonged latencies of the VEMP in patients with type 1 diabetes mellitus suggest lesions in the retrolabyrinthine, especially in the vestibulospinal tract. Nevertheless, due to the limited number of examined samples, further investigation with more patients should be performed.

Background and Aim: Navigation information is processed and stored in different brain areas such as hippocampus. Since multiple pathways has been reported between vestibular nuclei and hippocampus and also cognitive dysfunction specifically in spatial memory is induced by vestibular deficits, it can be assumed that vestibular system stimulation ameliorates spatial memory. The aim of study was to evaluate the effect of galvanic vestibular stimulation on normal individual’s spatial memory.

Methods: In this experimental-interventional study, sixty 18-30-years-old women were randomly allocated in intervention and control groups. Intervention group undergone subthreshold bilateral bipolar galvanic vestibular stimulation and control group received sham stimulation. Stimulation was presented for 15 minutes. Corsi Block Tapping (CBT) test scores were compared before and after subthreshold bipolar galvanic vestibular stimulation exposure or no stimulation in each group and between groups.

Results: All test parameters were the same in both groups before stimulation (p<0.050). There were significant improvement in block span, total score and learning score in intervention group after galvanic vestibular stimulation (p<0.050), no significant difference in delayed score (p=0.600). Learning score was improved (p=0.003) and delayed score was deteriorated (p=0.010) in control group. Percentages of block span and total score in intervention group were significantly different compared to the other group (p<0.050).

Conclusion: Galvanic vestibular stimulation improves short-term and long-term spatial memory. This test may inherently have learning effect that is not influenced by stimulation.

Background and Aim: Cervical vestibular-evoked myogenic potential (cVEMP) is one of the diagnostic tests used in assessing vestibular function. Two aims of this study were to investigate implications of cervical vestibular evoked myogenic potential in children with spastic cerebral palsy (7-12 years), and to compare vestibular function in these children and normal children.

Methods: In this cross-sectional study, myogenic potential was recorded in 31 children with spastic cerebral palsy (8 girls, 23 boys,7-12 years of age, with mean age of 8.77 years old and standard deviation of 1.52 years) and 31 normal children (13 girls, 18 boys with mean age of 8.77 years and standard deviation of 1.52 years). Cervical vestibular evoked myogenic potential was recorded with 500 Hz tone burst. The recorded parameters included p13 and n23 latency, p13-n23 pick to pick amplitude, and threshold.

Results: Myogenic Potential was recorded in 31 normal children. They had bilateral responses. In children with cerebral palsy, 21 children showed bilateral responses, 3 children had only right-sided responses, 8 children had only left-sided responses, and two children did not show any responses. The statistical significant differences were shown between the two groups in n23, p13-n23 pick to pick amplitude, and threshold (p<0.05).

Conclusion: These findings showed that cervical vestibular evoked myogenic potential can be used in children with cerebral palsy. There were significant differences in myogenic potential parameters between the two groups. More studies are needed to investigate the causes of these differences.

Background and Aim: Creatine plays an important role in the regulation of cellular energy in high energy demand organs such as the inner ear. It is also believed to play a protective role. This article reviewed the mechanisms and effects of creatine on the auditory and vestibular systems.

Recent Findings: Creatine transporters and creatine kinase enzymes are involved in converting creatine to creatine phosphate. Phosphate is a fuel cell available in the cochlear and vestibular hair cells and the protective cells, striavascularis, peripheral and central neural pathways to the auditory cortex. It provides essential ATP for auditory and vestibular system performance. Creatine kinase prevents cochlear damage by regulating the metabolism of energy in marginal layers of the striavascularis and preventing free radical production in stressful situations. It also plays an important role in vestibular compensation. Creatine kinase dysfunction leads to an increase in the threshold of auditory brainstem potentials and a reduction in vestibular performance. The use of creatine improves vestibular evoked myogenic potentials and neurologic symptoms.

Conclusion: Creatine and creatine kinase protein is essential for normal hearing and balance function and sensitivity. Creatine kinase deficiency impairs the functioning of these two systems however, creatine consumption may boost the sensitivity of the vestibular system and neurological performance. Effects of the creatine consumption on the auditory system have not yet been examined.