DOI: https://doi.org/10.36347/sasjm.2026.v12i05.002

Pages: 387-389

Background: Megalencephalic leukoencephalopathy with subcortical cysts (MLC), also known as Van der Knaap disease, is a rare genetic leukodystrophy characterized by early-onset macrocephaly, mild initial neurological impairment, and distinctive MRI findings. Case presentation: We report the case of an 8-year-old boy presenting with motor developmental delay, progressive macrocephaly, and generalized tonic–clonic seizures. Brain MRI demonstrated diffuse, bilateral, and symmetrical supratentorial white matter abnormalities associated with subcortical cysts in the temporo-parietal regions. Imaging findings: MRI showed diffuse swelling of the cerebral white matter with hypointensity on T1-weighted images and hyperintensity on T2-weighted and FLAIR sequences, without diffusion restriction or post-contrast enhancement. Multiple bilateral temporo-parietal subcortical cysts were identified. These imaging features were highly suggestive of MLC. Conclusion: This case highlights the crucial role of MRI in the positive diagnosis of MLC and in differentiating it from other childhood leukodystrophies.