Analysis and clinical correlates of 20 Hz photic driving on routine EEG in migraine

Abstract

Abstract:Enhanced photic driving (PD) during high frequency flicker stimulation, the so-called H response, is a classical feature of migraine patients between attacks, but is thought to be of poor clinical utility. Visual inspection of the EEG for its detection may not be reliable, however, and data on its possible correlations with clinical features and migraine pathophysiology are scarce.We have compared visual inspection and EEG spectral analysis to detect abnormal PD in 280 consecutive migraine patients of our headache clinic (episodic migraine without aura, n=171; chronic migraine, n=48; migraine with aura, n=61) and in a group of 24 non-migrainous neurological controls. Spectral frequency analyses were performed blindly by one of us (YF). On visual inspection, 50.4% of migraineurs were thought to have increased 20Hz PD. After spectral analysis, only 62.4% of them had PD power superior to the mean+95%CI of the control group. Sensitivity of visually identified PD was 82.24%, specificity 69.36%. Increased PD on spectral analysis was more prevalent in episodic migraine than in chronic migraine, in patients with low attack frequency, in those with ictal autonomic symptoms in addition to nausea and in those with a strong family history of migraine. We confirm therefore that 20Hz photic driving is of little diagnostic utility and its prevalence in migraine overestimated on visual inspection. Its presence on spectral analysis of the EEG, however, might be of pathophysiological interest, as it identifies subgroups of migraineurs of whom the common denominator could be lack of habituation of cortical responses during repetitive stimulation. We have compared visual inspection and EEG spectral analysis to detect abnormal PD in 280 consecutive migraine patients of our headache clinic (episodic migraine without aura, n=171; chronic migraine, n=48; migraine with aura, n=61) and in a group of 24 non-migrainous neurological controls. Spectral frequency analyses were performed blindly by one of us (YF).On visual inspection, 50.4% of migraineurs were thought to have increased 20Hz PD. After spectral analysis, only 62.4% of them had PD power superior to the mean+95%CI of the control group. Sensitivity of visually identified PD was 82.24%, specificity 69.36%.Increased PD on spectral analysis was more prevalent in episodic migraine than in chronic migraine, in patients with low attack frequency, in those with ictal autonomic symptoms in addition to nausea and in those with a strong family history of migraine.We confirm therefore that 20Hz photic driving is of little diagnostic utility and its prevalence in migraine overestimated on visual inspection. Its presence on spectral analysis of the EEG, however, might be of pathophysiological interest, as it identifies subgroups of migraineurs of whom the common denominator could be lack of habituation of cortical responses during repetitive stimulation.

Visual input drives increased occipital responsiveness and harmonized oscillations in multiple cortical areas in migraineurs

“…This finding can be seen in the light of a lack of habituation to slowly flickering light in migraineurs. Of note, fast flickering frequencies around 20 Hz, known as photic driving, show inconsistent results (Chorlton and Kane, 2000; Fogang et al, 2015). Nevertheless, similar findings of a lack of habituation are known to happen in migraine patients also in other sensory domains (Magis et al, 2016, Magis et al, 2013) and have been discussed as a hyperresponsive cortical reaction to sensory (here: visual) input.…”

Visually sensitive seizures: An updated review by the Epilepsy Foundation

“…102 Other studies, however, have argued for a cortical hyperexcitability state. 103 Fogang and colleagues 104 documented good sensitivity (82.24%), but moderate specificity (69.36%), of the visually-identified photic driving H response (enhanced photic driving during high-frequency flicker stimulation) in migraineurs.…”

Profile of Photic Driving Inelectroence Phalography Records at Mohammad Hoesin Hospital Palembang

“…This is because the reflection of central sensitization, in general, is caused by pain. [9] The existence of this difference is likely due to the most distribution of patients who performed the most EEG recording is epilepsy compared to pain due to a migraine itself, thus the limitations of this study in exploring the PD response itself in terms of etiological diagnosis variables.…”