Related Experiment Video
Updated: Jun 2, 2026
Magnetic Resonance Imaging of Multiple Sclerosis at 7.0 Tesla
Published on: February 19, 2021
Punctate white matter lesions in infants: new insights using susceptibility-weighted imaging
Tetsu Niwa1, Linda S de Vries, Manon J N L Benders
1Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100, PO Box 85500, 3508 GA, Utrecht, The Netherlands. tniwa@kcmc.jp
Introduction:
Punctate white matter lesions (PWML) are recognized with magnetic resonance imaging (MRI) as hypersignal on T1-weighted imaging and hyposignal on T2-weighted imaging. Our aim was to assess how often a hemorrhagic component was present in PWML using susceptibility-weighted imaging (SWI).
Methods:
Seventeen preterm (gestational age, 25-34 weeks) and seven full-term infants (age at MRI, 37-42 weeks) with PWML were included. Seven preterm infants had sequential MRIs. PWML were diagnosed with conventional MRI and compared with SWI, where signal loss is suggestive of hemorrhage. The pattern of associated brain lesions was taken into account, and the percentage of lesions with signal loss on SWI was calculated for each infant.
Results:
A significantly higher percentage of signal loss on SWI (median, 93.9%) was found among infants with germinal matrix and intraventricular hemorrhage as the primary diagnosis (n = 8) compared to those with a primary diagnosis of white matter injury (n = 14; median, 14.2%; p < 0.01). In the infants with serial MRIs, a reduction in the number of PWML and/or signal loss on SWI was noted at term equivalent age. In the patient who died, cystic lesions, associated with hemorrhage and gliosis, were demonstrated on histology.
Conclusions:
SWI can distinguish hemorrhagic and non-hemorrhagic PWML. Signal loss on SWI was more common when PWML were associated with an intraventricular hemorrhage. Longitudinal imaging showed a decrease in the number of PWML over time, with some PWML no longer showing signal loss on SWI, suggesting early gliosis.
Insights
Susceptibility-weighted imaging (SWI) helps identify hemorrhagic components in punctate white matter lesions (PWML). Hemorrhagic PWML were more frequent when associated with intraventricular hemorrhage in infants.
Area of Science:
- Neonatal neurology
- Pediatric neuroradiology
- Neuroimaging
Background:
- Punctate white matter lesions (PWML) are identified on MRI as T1 hypersignal and T2 hyposignal.
- The presence of a hemorrhagic component in PWML has not been fully elucidated.
Purpose of the Study:
- To determine the frequency of hemorrhage in PWML using susceptibility-weighted imaging (SWI).
- To differentiate hemorrhagic from non-hemorrhagic PWML.
Main Methods:
- Seventeen preterm and seven full-term infants with PWML were evaluated using conventional MRI and SWI.
- Sequential MRIs were performed on seven preterm infants.
- The percentage of PWML with signal loss on SWI, indicative of hemorrhage, was calculated.
Main Results:
- A significantly higher percentage of signal loss on SWI was observed in infants with germinal matrix and intraventricular hemorrhage (93.9%) compared to those with white matter injury (14.2%).
- Longitudinal imaging revealed a decrease in PWML and/or SWI signal loss over time.
- Histology in one deceased patient showed cystic lesions associated with hemorrhage and gliosis.
Conclusions:
- SWI effectively distinguishes hemorrhagic from non-hemorrhagic PWML.
- Hemorrhagic PWML are more common when associated with intraventricular hemorrhage.
- PWML decrease over time, with some resolving or showing signs of early gliosis.
