Headache & Pain
Dec. 22, 2022
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Neurophysiological investigations in a 26-year-old man with onset of epilepsia partialis continua at the age of 25. (A,C) Dermatomal and somatosensory potentials are gigantic on the right side (from stimulation of the left). Note that the maximum amplitude of the dermatomal potentials is obtained when the S1 dermatome is stimulated. (B) C reflex of around 65 ms latency is obtained only from muscles of the left leg stimulating the peroneal nerve (similar responses were also obtained from other left-sided leg muscles by stimulating other left leg nerves or by tapping for the knee jerk). (D) Jerk-locked back-averaged cortical potentials appear in the contralateral primary motor area preceding the jerks by 25 ms (positive peak). (Courtesy of C P Panayiotopoulos. From: Panayiotopoulos CP. A Clinical Guide to Epileptic Syndromes and Their Treatment. Revised 2nd ed. London: Springer, 2010.)