Radiology MRI

Note restricted diffusion focus in the right frontoparietal region showing high signal on DWI and low on ADC. Infarct? No. Sagittal T2, transversal FLAIR and contrast enhanced T1 reveal multiple white matter lesions located in perivascular spaces, that are mostly the type of "black holes" representing substance loss. There is even some periphery contrast enhancement in the frontal lesion. Therefore restricted diffusion on the above image represents Intramyelinic Edema of Acute (Cytotoxic) Plaques in Multiple Sclerosis  patient. Old MS plaques show on DWI and ADC as high signal.

Excellent link to great initiative by Val M. Runge, MD publishing free online Clinical MRI Textbook . Thank you for this valuable resource. Also thanks for the link to Sumer's Radiology Site .

MRI showing non-enhancing hypothalamic mass located between mammillary bodies and infundibulum at the tuber cinereum. Mass represents  Tuber Cinereum Hamartoma , also known as Hypothalamic Hamartoma (HH). It is a non-neoplastic congenital gray matter heterotopia. It can be associated with characteristic gelastic seizures - laughing epilepsy . It is a classic case for all sort of radiology exams!