History : The 13 d/o male infant had gradually decreased appetite since 5 days ago and poor activity was noted. Bicycling movement was noted. Image finding : MRI of brain without contrast shows -There is no myelination at the dorsal brin stem,cerebellar peduncles, post. limb & ventrolateral thalami . Delayed (no) myelination as mentioned above. Diagnosis : Delayed myelination