To study the localizing & lateralizing significance of initial, mid-ictal and ictal-end head position in versive seizures with secondary generalization.

Version, defined as forced, sustained, and involuntary turning of the eyes and head. A highly reliable lateralizing sign of epileptogenic-zone to contralateral hemisphere. However, does not have a localizing significance.

The latency of version from seizure onset(T1) was 47.6±10.2sec and 27.7±10.7sec in temporal-lobe and frontal-lobe groups, respectively(p <0.0001). Occipital-lobe group had longest latency of 93.4±54.4sec(p <0.0001). The latency of secondary GTCS(T4) from initial version was 15.9±3.7sec in temporal-lobe group compared to frontal-lobe and parietal-lobe groups at 20.4±7.0sec(p=0.0097) and 21.6±10.1sec(p=0.0377). Occipital-lobe group had shortest latency at 10.6±5.3 sec(p=0.0085).

In 44 out of 50 patients, the head position evolved to a midline position from initial version. In 20 out of 50 patients, the head position further evolved to an ictal-end head position by the end of the GTC phase. In these 20 patients, the ictal-end head position was contralateral to the direction of initial version in 100% of cases. This ictal-end head position was ipsilateral to the seizure-onset zone in 100% of the cases. 10 out of these 20 patients had corresponding ipsilateral ictal-end clonic movement.

Latency of onset of initial version has a localizing significance for seizure-onset zone with the frontal-lobe group having the shortest, while occipital-lobe group has the longest. This is consistent with the relative physical distance of the frontal eye-field from these seizure-onset zones. Ictal-end head position contralateral to the initial version occurs in 40% of focal-epilepsies and is always ipsilateral to the seizure-onset zone.