Transient loss of wakefulness with falls in temporal lobe epilepsy: A retrospective single-centre study

Introduction: Focal impaired awareness seizures in temporal lobe epilepsy (TLE) typically involve behavioural arrest and automatisms with preserved posture. However, some patients can exhibit a transient loss of wakefulness with fall without any overt motor manifestations, a phenomenon previously described as “temporal lobe syncope.” However, previous reports did not always rigorously exclude FBTCS or ictal asystole. Herein, we aimed to reappraise this semiology by excluding these conditions using simultaneous video-electroencephalogram (VEEG) and electrocardiogram (ECG), clarifying its clinical characteristics.
Methods: We retrospectively analysed 65 patients with drug-resistant TLE who underwent surgery between April 2017 and December 2025. Seizures with transient loss of wakefulness with fall were defined as events without generalized motor manifestations or ECG changes, such as bradycardia or asystole. Outcomes were assessed using the ILAE seizure outcome classification.
Results: Three of 65 patients exhibited seizures characterised by transient loss of wakefulness with fall. All patients were clinically diagnosed with left TLE, and these seizures developed at least 10 years after epilepsy onset. Simultaneous VEEG and ECG excluded ictal asystole and FBTCS as the causes of the falls. One patient achieved seizure freedom after anterior temporal lobectomy, whereas the other two patients did not achieve seizure freedom after surgery.
Conclusion: Our findings suggest that transient loss of wakefulness in TLE patients may represent a distinct seizure semiology that should be differentiated from impaired awareness and from other causes of fall. Although the underlying mechanism remains uncertain, distinguishing wakefulness from awareness may provide a useful conceptual framework for understanding disorders of consciousness during epileptic seizures.