PT  - JOURNAL ARTICLE
AU  - Mike P Wattjes
AU  - Anke Vennegoor
AU  - Martijn D Steenwijk
AU  - Marlieke de Vos
AU  - Joep Killestein
AU  - Bob W van Oosten
AU  - Jop Mostert
AU  - Dorine A Siepman
AU  - Wiebe Moll
AU  - Alex E L van Golde
AU  - Stephan T F M Frequin
AU  - Nancy D Richert
AU  - Frederik Barkhof
TI  - MRI pattern in asymptomatic natalizumab-associated PML
AID  - 10.1136/jnnp-2014-308630
DP  - 2015 Jul 01
TA  - Journal of Neurology, Neurosurgery & Psychiatry
PG  - 793--798
VI  - 86
IP  - 7
4099  - http://jnnp.bmj.com/content/86/7/793.short
4100  - http://jnnp.bmj.com/content/86/7/793.full
SO  - J Neurol Neurosurg Psychiatry2015 Jul 01; 86
AB  - Objective To investigate the MRI manifestation pattern of asymptomatic natalizumab-associated progressive multifocal leukoencephalopathy (PML) in patients with multiple sclerosis (MS).Methods 18 patients with MS with natalizumab-associated PML lesions on MRI were included. In 6 patients, the PML lesions were identified on MRI prospectively and in 12 patients PML lesions were identified retrospectively. MRI sequences were analysed for PML lesion distribution, appearance, grey matter/white matter involvement and possible signs of inflammation. Lesion probability maps were created to demonstrate lesion distribution pattern.Results The frontal lobe was involved in 14 patients (77.8%) and the parietal lobe in 4 patients (22.2%). Most patients presented with focal lesions (13 patients, 72.2%) involving one single lobe (12 patients, 66.7%). The cortical grey matter was affected in 15 patients (83.3%) and 13 patients (72.2%) presented with a combination of cortical grey and white matter involvement. Signs of inflammation were detected in 7 patients (38.8%). Among patients with available diffusion-weighted imaging, 6 patients (40%) did not show high-signal-intensity lesions. A classical imaging pattern including unilateral and unilobar focal lesions in the frontal lobe affecting the cortical grey matter or the cortical grey and adjacent white matter was observed in 8 patients (44.4%).Conclusions Asymptomatic natalizumab-associated PML manifestations on MRI show a rather localised disease, frequently located in the frontal lobes, affecting the cortical grey matter and adjacent juxtacortical white matter. Awareness of this lesion pattern facilitates an earlier diagnosis of natalizumab-associated PML in an asymptomatic stage associated with a more favourable prognosis.