Predictive Value of Unilateral Hand Automatism and Brain Positron Emission Tomography Scan in Temporal Lobe Epilepsy Surgery Outcomes

OBJECTIVES: This study aimed to identify the lateralizing value of unilateral hand automatism, with or without concomitant contralateral hand dystonic posturing, in mesial temporal lobe epilepsy (MTLE) and to determine surgical outcomes in patients who underwent resection. METHODS: In this retrospective chart review study, we reviewed video recordings of 50 patients who consecutively underwent presurgical evaluations with ictal video-electroencephalogram recordings between 2018 and 2022 and had epilepsy surgery for intractable MTLE. RESULTS: All patients with right-hand automatism without contralateral dystonia (10 patients) had ipsilateral right MTLE, whereas only 50% of patients with right-hand automatism and associated contralateral dystonia (8 patients) did. Sixteen patients had left-hand automatism with contralateral dystonia, of which 68% had ipsilateral left MTLE, whereas only 2 of 6 patients with only left-hand automatism had similar findings. A brain positron emission tomography (PET) scan showed right temporal hypometabolism in 23 patients (46%), whereas 19 patients (38%) had left temporal hypometabolism. 42 (84%) patients had a class I surgical outcome (free of disabling seizures) according to the Engel Classification, a favorable outcome. Lateralization of the PET scan was significantly associated with the best surgical outcome. CONCLUSION: This study showed that unilateral upper-limb automatisms in MTLE occur mostly ipsilaterally to the epileptogenic zone, and that the right hand is more sensitive and specific when automatisms occur. Left upper-limb automatism with contralateral dystonia is associated with a higher likelihood of an ipsilateral left epileptogenic focus. The brain PET scan best predicted surgical outcomes in MTLE.