Can a finding of cervical vestibular evoked myogenic potentials contribute to vestibular migraine diagnostics?

AIM: To investigate differences in vestibular evoked myogenic potentials (VEMP) results with patients suffering from vestibular migraine and healthy people, taking into consideration values of threshold and latency of occurrence of the characteristic wave complex, size of amplitude, and interaural amplitude ratio. According to the results, determine the importance and usefulness of VEMP in vestibular migraine diagnostics. METHODS: A total number of 62 subjects were included in the study, 32 of them belonging to a group of patients suffering from vestibular migraine (VM), while other 30 were in a control group of healthy subjects. Information was collected during the diagnostic evaluation. General and otoneurological history of patients and bedside tests, audiological results, videonystagmography and cervical vestibular evoked myogenic potentials (cVEMP) were made. RESULTS: There was a difference in an interaural ratio of amplitudes in the experimental and control groups, but it was not found to be clinically significant. By ToneBurst 500 Hz method, the interaural amplitude ratio higher than 35% was measured in 46.97% subjects, while the response was totally unilaterally missing in 28.8% patients. CONCLUSION: Even the sophisticated method as cVEMP does not give the ultimate result confirming the vestibular migraine diagnosis, and neither do other diagnostic methods. cVEMP result can contribute to the completion of full mosaic of vestibular migraine diagnostics.

[CROATIAN GUIDELINES FOR DIAGNOSIS AND MANAGEMENT OF BENIGN PAROXYSMAL POSITIONAL VERTIGO (BPPV)]. / HRVATSKE SMJERNICE ZA DIJAGNOSTIKU I LIJECENJE BENIGNOGA PAROKSIZMALNOG POZICIJSKOG VERTIGA (BPPV-A).

BPPV is generally the most common cause of vertigo, caused by a pinch-off of tiny calcium carbonate crystals (called the otoconia or the otoliths) from the macula utriculi, most frequently due to the degenerative processes or a trauma, whereby the crystals, under the action of gravity in certain head positions coinciding with its direction, arrive to some of the semicircular canals, usually the posterior one, due to the existent anatomical circumstances and relationships, thus creating an inadequate stimulus of the cupular senses while floating through the endolymph and provoking symptoms of a strong and short-term dizziness. Two main clinical forms can be distinguished: canalolythiasis, with an accommodation of otolithic debris in the semicircular canal, and cupulolythiasis, with their location immediately next to the cupular sense. The diagnosis is established by a positive positioning test, Dix-Hallpike for the posterior and the supine roll for the lateral canal. Although one can expect a spontaneous recovery subsequent to few weeks or months, various methods of otolith repositioning to a less sensitive place lead to a prompt improvement while reducing or withdrawing the symptoms completely. These guidelines are intended for all who treat the BPPV in their work, with an intention to assist in the diagnosis and application of an appropriate therapeutic method.

Importance of accurate diagnosis in benign paroxysmal positional vertigo (BPPV) therapy.

AIM: To determine the importance of accurate topological diagnostics of the otolith and the differentiation of certain clinical forms of benign paroxysmal positional vertigo (BPPV). METHODS: A prospective study was conducted at the County General Hospital Vukovar in the period from January 2011 till January 2012. A total of 81 patients with BPPV, 59 females (72.84%) and 22 (27.16%) males (p less than 0.001), mean age 60.1 (± 12.1) were examined. The diagnosis was confirmed and documented by videonystagmography (VNG). The disability due to disease and risk of falling were monitored by filling in the Dizziness Handicap Inventory (DHI) and Activities-specific Balance Confidence Scale (ABC) questionnaires at the beginning and at the end of the repositioning treatment. RESULTS: In 79 (97.3%) patients posterior semicircular canal was affected, and in a small number of patients, two (2.47%) the lateral one. After the repositioning procedures were performed, there was a significant reduction or complete elimination of symptoms in the majority of subjects, 76 (93.82%). The median total DHI sum amounted to 50.5 (± 22.2) at the beginning and 20.4 (± 18.5) at the end of the study (p less than 0.00). Similarly, the results of ABC questionnaires at the beginning of the study demonstrated a result of 59.2% (± 22.4%), and at the end of the treatment the average result of examinees was significantly higher, 84.9% (± 15.2%) (p less than 0.00). CONCLUSION: Although a subjectively positive Dix-Hallpike or a "supine roll" test is sufficient for the diagnosis of BPPV, it is necessary perform the VNG as well in order to precisely determine the exact localization of the otolith, so that an appropriate repositioning procedure can be applied.