1-Periventricular leukomalacia (PVL) is the second most common CNS complication in preterm infants, after periventricular hemorrhage.
2-Periventricular leukomalacia is pathologically characterized by the softening of periventricular white matter as a result of vascular ischemia between 26 and 34 weeks of gestation.

Acute stage of periventricular leukomalacia (PVL). Fluid-attenuated inversion recovery (FLAIR) MRI shows bilateral periventricular hyperintensity.

Late-stage periventricular leukomalacia (PVL). Sagittal T1-weighted MRI shows an atrophied, irregular corpus callosum and atrophic brain parenchyma.

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