Related Experiment Video
Updated: Jun 25, 2026
Simultaneous PET/MRI Imaging During Mouse Cerebral Hypoxia-ischemia
Published on: September 20, 2015
Relative decrease in signal intensity of subcortical white matter in spontaneous intracranial hypotension on
M Adachi1, S Mugikura, A Shibata
1Department of Radiology, Ohshima Clinic, Yamagata, Japan. miadchi@beach.ocn.ne.jp
Background And Purpose:
In reviewing MR images of patients with spontaneous intracranial hypotension (SIH), we found an accentuated decrease in the subcortical white matter on fluid-attenuated inversion recovery (FLAIR) images. Our aim was to determine whether the signal intensity of the subcortical white matter decreases on FLAIR and T2-weighted images in SIH.
Materials And Methods:
We retrospectively examined pretreatment MR images including 7 FLAIR and 10 T2-weighted images obtained from 10 patients with SIH and follow-up images (5 FLAIR and 7 T2-weighted images). Two observers measured the signal intensities in the subcortical white matter on MR images at the level of the centrum semiovale and, to calculate the signal intensity ratios, measured those of the adjacent cortex and corpus callosum. Furthermore, 4 observers performed visual evaluation for accentuated signal intensity decreases for receiver operating characteristic (ROC) analysis.
Results:
The intensity ratios of the subcortical white matter, both to the adjacent cortex and corpus callosum, were significantly different between the control and pretreatment images in SIH and between pretreatment and follow-up images in SIH on FLAIR images, whereas these showed no significant differences between the control and follow-up images in SIH. On visual inspection, an accentuated decrease in signal intensity in the subcortical white matter was shown on pretreatment FLAIR images, which returned to the control level on follow-up images. However, on the T2-weighted images we could hardly recognize the decrease in the signal intensity.
Conclusions:
Awareness of the decreased signal intensity of the subcortical white matter on FLAIR images could help in the diagnosis of SIH.
Insights
Subcortical white matter signal intensity decreases on FLAIR MRI in spontaneous intracranial hypotension (SIH). This finding, not seen on T2-weighted images, aids SIH diagnosis.
Area of Science:
- Neuroradiology
- Neuroimaging
- White Matter Diseases
Background:
- Spontaneous intracranial hypotension (SIH) is a condition characterized by cerebrospinal fluid (CSF) leakage.
- Magnetic Resonance Imaging (MRI) is crucial for diagnosing SIH.
- Previous observations noted reduced subcortical white matter signal on FLAIR images in SIH patients.
Purpose of the Study:
- To investigate the signal intensity changes in subcortical white matter on FLAIR and T2-weighted MRI in patients with SIH.
- To determine if decreased subcortical white matter signal intensity is a reliable imaging biomarker for SIH.
Main Methods:
- Retrospective analysis of pretreatment and follow-up MRI scans (FLAIR and T2-weighted) from 10 SIH patients.
- Measurement of signal intensities in subcortical white matter, adjacent cortex, and corpus callosum to calculate ratios.
- Visual evaluation by four observers for signal intensity decreases, analyzed using ROC curves.
Main Results:
- Significantly lower signal intensity ratios in subcortical white matter were observed on pretreatment FLAIR images compared to controls and follow-up images in SIH patients.
- These changes on FLAIR images normalized after treatment.
- A decrease in signal intensity was not readily apparent on T2-weighted images.
Conclusions:
- Decreased subcortical white matter signal intensity on FLAIR MRI is a characteristic finding in SIH.
- This imaging feature can assist in the diagnosis of spontaneous intracranial hypotension.
- FLAIR MRI is more sensitive than T2-weighted imaging for detecting this specific abnormality in SIH.
