Post-Stroke Seizure Disorder Terminology
The term for seizure disorder secondary to cerebrovascular accident is "post-stroke epilepsy" (PSE) when referring to recurrent unprovoked seizures, or "stroke-associated acute symptomatic seizures" when seizures occur within 7 days of the stroke. 1, 2
Key Terminology Distinctions
The classification of seizures following stroke depends critically on timing:
Early vs. Late Seizures
- Early seizures (also called "acute symptomatic seizures" or "stroke-associated acute symptomatic seizures") occur within 7 days of the stroke, most commonly within the first 24 hours 3, 1, 2
- Late seizures (also called "unprovoked seizures") occur more than 7 days after the stroke 1, 2
- The 7-day cutoff is the standard temporal definition used to distinguish provoked from unprovoked seizures in stroke patients 1, 2
Post-Stroke Epilepsy Definition
- Post-stroke epilepsy (PSE) is diagnosed when a patient experiences unprovoked seizures occurring more than 7 days after stroke 2
- A single late post-stroke seizure carries a recurrence risk as high as 71.5% at 10 years and is itself diagnostic of PSE 2
- This aligns with the International League Against Epilepsy (ILAE) definition requiring either two unprovoked seizures or one unprovoked seizure with high recurrence probability 4
Clinical Context and Epidemiology
Incidence and Timing
- Seizures occur in 4-10% of stroke patients during the acute period, with the true risk toward the lower end of estimates 3
- Early seizures are more common than late seizures and typically present as focal motor seizures with or without secondary generalization 3
- Among patients with stroke-associated acute symptomatic seizures, 29.3% will develop PSE 5
Risk Factors for PSE Development
The following factors predict progression from acute symptomatic seizures to PSE:
- NIHSS score >14 (more severe neurological deficits) increases PSE risk with hazard ratio 2.98 5
- Multiple acute symptomatic seizures (rather than a single seizure) increases risk with hazard ratio 5.08 5
- Longer interval from stroke to first seizure (days 4-7 post-stroke versus earlier) increases risk with hazard ratio 2.51 5
- Cortical involvement of the stroke is consistently associated with higher seizure risk, while deep-seated or infratentorial lesions rarely produce seizures 6
- Multilobar involvement in hemorrhagic stroke increases PSE risk with hazard ratio 4.80 5
Common Clinical Pitfall
A critical distinction: The term "epilepsy" should not be applied to early seizures occurring within 7 days of stroke, as these are provoked seizures with different recurrence risks and treatment implications 1, 2. Recurrent seizures develop in only 20-80% of patients with early seizures, whereas a single late seizure has >70% recurrence risk 3, 2.
Alternative Terminology in Literature
- Some sources use "poststroke seizures" as a general term encompassing both early and late seizures 6, 7
- The term "stroke-related epilepsy" may also appear but is less precise than PSE 7
- Older literature may use "vascular epilepsy" though this broader term includes seizures from all cerebrovascular causes 6