Jerome Hodel, Presenter: Nothing to Disclose

Olivier Outteryck, Abstract Co-Author: Nothing to Disclose

Anne-Laure Bocher toledano MD, Abstract Co-Author: Nothing to Disclose

Helene Zephir, Abstract Co-Author: Nothing to Disclose

Celine Dubron, Abstract Co-Author: Nothing to Disclose

Marc Zins MD, Abstract Co-Author: Nothing to Disclose

Jean-Pierre Pruvo, Abstract Co-Author: Nothing to Disclose

Patrick Vermersch, Abstract Co-Author: Nothing to Disclose

Xavier Leclerc MD, PhD, Abstract Co-Author: Nothing to Disclose

The purpose of this exhibit is: 1. To describe the key imaging features of Natalizumab associated PML 2. To explain the utility of brain MRI in the early diagnosis Summary: Natalizumab, an effective treatment in multiple sclerosis, is associated with a risk of PML. Brain MRI plays a major role for the early diagnosis of PML. FLAIR is considered as a reference standard for detecting supratentorial PML lesions while T2w images improve the detection of infra-tentorial lesions and intralesional microcysts. Diffusion may suggest acute demyelination. 3D TSE MR sequences (Cube, GE; SPACE, Siemens; Brainview, Philips) may improve the detection of small PML lesions due to better image contrast and spatial resolution. Specific imaging findings for early PML include: - subcortical location involving U-fibers; - ill defined border toward the white matter; - increased signal intensity on both T2 and diffusion weighted images. Key imaging features of natalizumab-associated PML are: - subcortical U-fibers involvement, - extension to adjacent gray matter, - peripheral small punctuate hyperintense lesions and intra-lesional microcysts (« milky way appearance »)  

1) MR protocol 2) Pictorial review: imaging features of natalizumab-associated PML 3) Pitfalls and mimics 4) Take home messages  

http://abstract.rsna.org/uploads/2014/14010386/14010386_q3so.pdf

Hodel, J, Outteryck, O, Bocher toledano, A, Zephir, H, Dubron, C, Zins, M, Pruvo, J, Vermersch, P, Leclerc, X, Imaging Findings in Patients with Natalizumab-related Progressive Multifocal Leukoencephalopathy.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14010386.html