Postictal syndrome: The forgotten continent. An overview of the clinical, biochemical and imaging features

Insights into Postictal Psychosis, from functional imaging and EEG: A systematic review

Multiple hypotheses exist about the pathophysiology of Postictal Psychosis (PIP). As the clinical manifestations of PIP are roughly stereotyped, we assumed the existence of a common neurological pathway. This study aimed to determine if a specific brain network sustained the psychotic episode, regardless of the localization of the epileptogenic zone. We conducted a systematic review following the PRISMA guidelines. We included a total of 24 studies providing electrophysiological results(n=22) and metabolic imaging performed during the PIP(n=5). Temporal and frontal lobes seemed frequently involved, without clear evidence for lateralization. The EEG patterns were heterogenous, varying from unchanged to diffuse slowing. Metabolic pattern showed an increased perfusion within temporal and frontal lobes during PIP. These results correspond to the patterns described during postictal state, but they persisted throughout PIP, within regions larger than the epileptogenic zone and resolved with the recovery. PIP symptoms are associated with an excessive persistence of postictal changes within extended frontotemporal networks. A hypothesis could be that PIP results from an abnormally prolonged and diffuse post-ictal dysregulation.

Todd's paralysis due to hyperperfusion syndrome after carotid endarterectomy mimicking postoperative stroke

Todd's paralysis is a neurological deficit that is observed in <10% of patients following epileptic seizures. Cerebral hyperperfusion syndrome (CHS) is a rare complication following carotid endarterectomy (CEA), seen in 0-3% of the patients, characterized by focal neurological deficit, headache, disorientation, and sometimes seizures. In this case report, we present a case of CHS after CEA followed by seizures and Todd's paralysis that mimicked postoperative stroke. A 75-year-old female patient was admitted for CEA of the right internal carotid artery, following a transient ischemic attack two months prior. Four hours after CEA with graft interposition, the patient suffered a temporary weakness of the left arm and leg followed by generalized spasms within a few seconds. CT angiography showed regular patency of the carotid arteries and the graft, and brain CT showed no sign of oedema, ischemia or hemorrhage. However, left-sided hemiplegia occurred following the seizure, and the patient suffered four more seizures over the next 48 hours, with persisting hemiplegia. On the second postoperative day, the motor skills of the left side fully recovered, and the patient was communicative, and of orderly mental status. Brain CT performed on the third postoperative day showed entire right hemisphere oedema. A moderate hemiparesis with seizures as a consequence of CHS after CEA has been described, however in all cases with seizures and hemiplegia, the underlying cause was always a verified stroke or intracerebral hemorrhage. This case highlights the importance of considering Todd's paralysis in patients with seizures after CEA due to CHS and prolonged periods of hemiplegia after the seizures.

Computed tomography perfusion stroke mimics on RAPID commercial software: A case-based review

Acute ischemic stroke (AIS) is a leading cause of morbidity worldwide and can present with nonspecific symptoms, making diagnosis difficult. Many neurologic diseases present similarly to stroke; stroke mimics account for up to half of all hospital admissions for stroke. Stroke therapies carry risk, so accurate diagnosis of AIS is crucial for prompt treatment and prevention of adverse outcomes for patients with stroke mimics. Computed tomography (CT) perfusion techniques have been used to distinguish between nonviable tissue and penumbra. RAPID is an operator-independent, automated CT perfusion imaging software that can aid clinicians in diagnosing strokes quickly and accurately. In this case-based review, we demonstrate the applications of RAPID in differentiating between strokes and stroke mimics.

The postictal state - What do we know?

This narrative review provides a broad and comprehensive overview of the most important discoveries on the postictal state over the past decades as well as recent developments. After a description and definition of the postictal state, we discuss postictal sypmtoms, their clinical manifestations, and related findings. Moreover, pathophysiological advances are reviewed, followed by current treatment options.