Comparison of cortical excitability in chronic migraine (transformed migraine) and migraine without aura. A transcranial magnetic stimulation study.
We studied the excitability of the motor cortex in patients with migraine without aura (MWOA) (n = 20) and with chronic migraine (CM) (n = 20) using transcranial magnetic stimulation (TMS). By using a 90-mm circular coil placed over the vertex and recording of the first dorsal interosseous muscle, we measured thresholds, latencies and amplitudes of motor evoked potentials and duration of cortical silent periods in patient groups and in controls (n = 20). No differences were found between groups for threshold, latency and amplitude values. However, the duration of the cortical silent period was longer in CM patients, being significantly different from both controls and MWOA. We suggest that either this difference in cortical excitability may develop during transformation from MWOA to CM or different pathophysiological mechanisms may play a role in these two headache syndromes.
Ozturk
Vesile
V
Dokuz Eylül University, Medical School, Department of Neurology, 35340, Izmir, Turkey. vesile.ozturk@deu.edu.tr
Cakmur
Raif
R
Donmez
Berril
B
Yener
Gorsev Gulmen
GG
Kursad
Fatma
F
Idiman
Fethi
F
D000328:Adult; D002908:Chronic Disease; D004574:Electromagnetic Fields; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020325:Migraine with Aura / Q000503:physiopathology*; D020326:Migraine without Aura / Q000503:physiopathology*; D009044:Motor Cortex / Q000503:physiopathology*; D018709:Statistics, Nonparametric