White matter changes seen after radiation therapy are termed what?

• A. Leukoencephalopathy
• B. Leukoencephalitis
• C. Leukodystrophy
• D. Leukomalacia

Answer: (A)

White matter changes after radiation therapy are best described as leukoencephalopathy. This term denotes disease or pathology of the brain’s white matter and is used broadly for white matter injury from various causes, including radiation. Radiation can damage oligodendrocytes and myelin, producing demyelination and diffuse white-matter signal changes on imaging, which fits the description of leukoencephalopathy.

Leukoencephalitis would imply inflammation of white matter, often infectious or autoimmune. Leukodystrophy refers to inherited disorders affecting myelin development or maintenance. Leukomalacia describes softening or necrosis of white matter due to ischemia, typically in premature infants.