BrainWaves #154 All that restricts does not infarct

MedLink Neurology Podcast is delighted to feature selected episodes from BrainWaves, courtesy of James E Siegler MD, its originator and host. BrainWaves is an academic audio podcast whose mission is to educate medical providers through clinical cases and topical reviews in neurology, medicine, and the humanities, and episodes originally aired from 2016 to 2021.

Originally released: January 9, 2020

The common teaching is that restricted diffusion on MRI indicates stroke—acute cerebral infarction--when, more specifically, the changes on DWI and ADC indicate impairment in the random movement of water molecules in a given tissue. With slower movement, as in energy-depleted tissues with failing ATP-dependent sodium/potassium channels, high cellularity, or a highly viscous extracellular space, there is restricted diffusion (of water) and a corresponding bright signal on DWI. These and other considerations are the focus of this week's episode of BrainWaves.

Produced by James E Siegler. Music courtesy of Uncanny and Kevin McLeod. Sound effects by Mike Koenig. BrainWaves' podcasts and online content are intended for medical education only and should not be used for clinical decision-making. Be sure to follow us on Twitter @brainwavesaudio for the latest updates to the podcast.

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We believe that the principles expressed or implied in the podcast remain valid, but certain details may be superseded by evolving knowledge since the episode’s original release date.