Computed Tomography Perfusion and Four‐Dimensional Computed Tomography Angiography for Evaluating Perfusion Abnormalities Associated With Epileptic Seizures
Yuji Hattori, Kazuto Kobayashi, Misao Akatsuka, Ryuichi Inoue, Natsumi Inoue, Masayoshi Yamasaki, Yutaka Naito, Akira TaniguchiABSTRACT
Background
Epileptic seizures are a major cause of stroke mimics in emergency settings and can induce transient cerebral hyperperfusion or hypoperfusion. Computed tomography perfusion (CTP) aids in distinguishing seizures from ischemic stroke; however, the contribution of four‐dimensional CT angiography (4D‐CTA) remains poorly defined.
Aim
To evaluate whether 4D‐CTA complements CTP in assessing seizure‐related perfusion abnormalities.
Methods
This retrospective analysis included 39 patients who underwent CTP and 4D‐CTA for suspected acute ischemic stroke and were ultimately diagnosed with epileptic seizures. Perfusion abnormalities on CTP and 4D‐CTA were visually assessed, and their associations with clinical variables and electroencephalography (EEG) findings were examined using Fisher's exact test and logistic regression.
Results
Perfusion abnormalities were detected in 15 of 39 patients (38.5%) on either CTP or 4D‐CTA: 6 demonstrated abnormalities on both modalities, 4 on CTP alone, and 5 on 4D‐CTA alone. Hyperperfusion on CTP frequently involved the thalamus, whereas perfusion changes and epileptiform discharges predominantly localized to the frontal and parietal regions. Epileptiform discharges on EEG were the only factor significantly associated with perfusion abnormalities.
Conclusion
Detection of perfusion abnormalities on CTP and 4D‐CTA supports the diagnosis of epileptic seizures in patients presenting with acute neurological symptoms in emergency settings, particularly when integrated with EEG and clinical findings. Because 4D‐CTA can be acquired concurrently with CTP without additional invasiveness or examination time, it serves as a practical complementary modality in multimodal imaging assessment.