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Updated: Jan 22, 2026

Digital Spatial Profiling for Characterization of the Microenvironment in Adult-Type Diffusely Infiltrating Glioma
Published on: September 13, 2022
Time-intensity Profiles and T1-corrected Arterial Transit Time from Multi-delay Pseudo-continuous ASL with
Koji Yamashita1, Makoto Obara2, Kazufumi Kikuchi3
1Department of Molecular and Imaging Diagnosis, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. yamashita.koji.659@m.kyushu-u.ac.jp.
Purpose:
The cerebral blood flow (CBF) measured by multi-delay ASL (4D-ASL) offers superior diagnostic performance compared to single-delay ASL-CBF for glioma grading. Dynamic changes in signal intensity (SI) and arterial transit time (ATT) obtained from 4D-ASL may also be key factors in differentiating adult-type diffuse glioma. Furthermore, the longitudinal relaxation time (T1) of brain tumor may influence on CBF and ATT when using ASL techniques. Our purpose was to determine if time-intensity profiles from 4D-ASL using a variable-TR scheme and T1-corrected ATT (ATTT1corr) could distinguish among adult-type diffuse gliomas.
Materials And Methods:
The 4D-ASL with a variable-TR scheme data were collected by changing the labeling duration (LD) and post-labeling delay (PLD). Data acquisition at each phase consisted of pre-saturation and control or labeling modules followed by data acquisition. A total of 14 LD and PLD combinations were used. In addition, T1 measurement was conducted using pseudo-continuous ASL with a variable-TR scheme, without label and background suppression pulses. The SI peak time was obtained based on the time-intensity curve. The SI peak time, ATT, and ATTT1corr were compared among adult-type diffuse gliomas.
Results:
Thirty patients were included in the study. ATT and the SI peak time in diffuse glioma with IDH-wildtype (IDHw) were significantly shorter than astrocytoma, IDH-mutant (p < 0.01, each). Moreover, ATTT1corr in astrocytoma, IDH-mutant was longer than the other types of diffuse glioma (p < 0.0001).
Conclusion:
The 4D-ASL with a variable-TR scheme includes ATTT1corr and the SI peak time could potentially improve the differential diagnosis of adult-type diffuse gliomas.
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