Hemodynamic state of periictal hyperperfusion revealed by arterial spin-labeling perfusion MR images with dual postlabeling delay

Kenta Takahara; Takato Morioka; Takafumi Shimogawa; Sei Haga; Katsuharu Kameda; Shoji Arihiro; Ayumi Sakata; Nobutaka Mukae; Koji Iihara

doi:10.1016/j.ensci.2018.06.001

Hemodynamic state of periictal hyperperfusion revealed by arterial spin-labeling perfusion MR images with dual postlabeling delay

eNeurologicalSci. 2018 Jun 26:12:5-18. doi: 10.1016/j.ensci.2018.06.001. eCollection 2018 Sep.

Authors

Kenta Takahara^{1

2}, Takato Morioka^{1

3}, Takafumi Shimogawa^{1

2

3}, Sei Haga¹, Katsuharu Kameda¹, Shoji Arihiro⁴, Ayumi Sakata⁵, Nobutaka Mukae², Koji Iihara²

Affiliations

¹ Department of Neurosurgery, Kyushu Rosai Hospital, 1-1 Sonekitamachi, Kokura Minami-Ku, Kitakyushu, Japan.
² Department of Neurosurgery, Graduate School of Medical Sciences, Kyusyu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Japan.
³ Department of Neurosurgery, Fukuoka Children's Hospital, 5-1-1 Kashiiteriha, Higashi-ku, Fukuoka, Japan.
⁴ Department of Cerebrovascular Disease, Kyushu Rosai Hospital, 1-1 Sonekitamachi, Kokura Minami-Ku, Kitakyushu, Japan.
⁵ Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Hospital, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Japan.

Abstract

Background: Magnetic resonance imaging (MRI), including perfusion MRI with arterial spin labeling (ASL) and diffusion-weighted imaging (DWI), are applied in the periictal detection of circulatory and metabolic consequences associated with epilepsy. Although previous report revealed that prolonged ictal hyperperfusion on ASL can be firstly detected and cortical hyperintensity of cytotoxic edema on DWI secondarily obtained from an epileptically activated cortex, the hemodynamic state of the periictal hyperperfusion has not been fully demonstrated.

Methods study-1: We retrospectively analyzed the relationship between seizure manifestations and the development of periictal MRI findings, in Case 1 with symptomatic partial epilepsy, who underwent repeated periictal ASL/DWI examination for three epileptic ictuses (one examination for each ictus). Study-2: We evaluated the hemodynamic state of periictal hyperperfusion with the ASL technique using a dual postlabeling delay (PLD) of 1.5 and 2.5 s in nine patients, according to the presence or absence of the localized epileptogenic lesion (EL) on conventional 3 T-MRI, who were divided into Group EL+ (six patients) and Group EL- (three patients).

Results: Study-1 confirmed that the stratified representation of the periictal MRI findings depends on the time interval between the ictal cessation and MRI examination in addition to the magnitude and duration of the epileptic activity. In Study-2, two types of periictal hyperperfusion were noted. In all six Group EL+ patients, periictal ASL findings showed "fast flow type". Markedly increased ASL signals were noted at the epileptically activated cortex, having a tight topographical relationship with EL, on ASL with a PLD of 1.5 s, which is decreased on ASL with a PLD of 2.5 s. In all three Group EL- patients, periictal ASL findings showed "gradual flow type", which is characterized by gradual signal increase of the epileptically activated cortex on ASL with a PLD of 1.5 and 2.5 s.

Conclusion: We confirmed that ASL hyperperfusion is superior to DWI in the periictal detection of epileptic events. ASL with dual PLD offers the ability to document two types of hemodynamics of periictal hyperperfusion.

Keywords: ASL, arterial spin labeling; ATA, arterial transit artifact; ATT, arterial transit time; Arterial spin labeling; CBF, cerebral blood flow; CT, computed tomography; Cytotoxic edema; DWI, diffusion-weighted imaging; Diffusion-weighted image; EEG, electroencephalography; EL, epileptogenic lesion; FLAIR, fluid attenuated inversion recovery; Ictal hyperperfusion; MRI, magnetic resonance imaging; PLD, postlabeling delay.