Abstracts

Rationale: Ictal dystonia (ID) is a well-known lateralizing ictal sign in temporal lobe epilepsy (TLE). In the literature, dystonia of the upper limbs has been most frequently reported. We performed a retrospective study to determine the incidence and localization of ID. Methods: The study included 142 patients (76 males; 66 females) with TLE. We analyzed 454 seizures. The localization of seizure onset zone (SOZ) was mesial in 112 and lateral in 30. Sixty-eight patients had left-sided TLE, 64 patients had right-sided TLE, and 10 of them had bitemporal epilepsy. MRI revealed mesial temporal sclerosis (MTS) in 64 patients; other kinds of lesions were present in 54 patients; 24 patients were non-lesional. Results: Some type of ID was present in 68 out of 142 patients (47.9%) and in 186 out of 454 seizures (40.9%). In all cases (100%), the ID was contralateral to the SOZ. Isolated upper limb ID was present in 94 seizures (50.5%), dystonia of both upper and lower limbs in 84 seizures (45.2%), and isolated lower limb ID in 8 seizures (4.3%). Some type of ID was significantly (p<0.001) more often present in patients with mesial SOZ than those with lateral SOZ (58.9% vs. 6.7%) and in MTS patients when compared to non-MTS patients (71.8% vs. 25.6%). Similarly, in the mesial group some type of ID was significantly (p<0.001) more often present in the patients with MTS than in the patients who had other kinds of lesions (71.8% vs. 41.7%). Conclusions: ID in TLE is a reliable lateralizing ictal sign. In almost half of the seizures, it is present in the form of hemidystonia, and isolated involvement of the lower limbs is possible. ID is typical for TLE with mesial onset, especially when MTS is the epileptogenic lesion.