Thomas Kucinski MD, Presenter: Nothing to Disclose

Einar Goebell MD, Abstract Co-Author: Nothing to Disclose

Jan Höltje MD, Abstract Co-Author: Nothing to Disclose

Jens Fiehler MD, Abstract Co-Author: Nothing to Disclose

Benjamin Geisler MD, Abstract Co-Author: Nothing to Disclose

Oliver Wittkugel MD, Abstract Co-Author: Nothing to Disclose

Ole Väterlein MD, Abstract Co-Author: Nothing to Disclose

Götz Thomalla MD, Abstract Co-Author: Nothing to Disclose

Joachim Röther MD, Abstract Co-Author: Nothing to Disclose

Hermann Zeumer MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

To test the prognostic value of MRI in acute ischemic stroke within 6 hours in real-time, prospective assessments by on call Neuroradiology staff.

From July 2002 to February 2004 consecutive patients (n = 75) eligible for thrombolytic therapy due to acute ischemic stroke of the middle cerebral artery were studied by stroke MRI within 0.9 – 5.7 h after symptom onset. MRI included MR-angiography (MRA), diffusion- (DWI) and perfusion-weighted (PWI) imaging with on-line calculation of cerebral blood flow (CBF) and volume (CBV), time-to-peak (TTP) and mean transit time (MTT) maps. PWI maps were derived from singular value decomposition of bolus tracking signal changes. Mismatch was defined as 20% larger PWI than DWI lesion. Occlusion type was classified in proximal (internal carotid artery, middle cerebral artery (MCA) trunk) or distal (MCA trifurcation or branch). Primary endpoint was lesion growth on follow-up scans (median 7 days after stroke).

63/75 (84%) patients were treated by thrombolysis. Real-time, prospective interpretation of MRI including DWI, MRA and PWI by on call staff members revealed a positive predictive value (PPV) of 0.43 for lesion growth (sensitivity 0.89, specificity 0.30). This was slightly better than prospective, but off-line reading of TTP (PPV 0.41) or MTT (0.40) mismatch alone. Off-line PPV of CBF (0.47) or CBV (0.53) mismatch was higher due to superior specificity. Highest prognostic value was found for combination of proximal occlusion type with CBF mismatch (PPV 0.56, sens. 0.79, spec. 0.64, OR 6.5, CI 2.3 – 18.2). A proximal occlusion was also more predictive (PPV 0.51, sens. 0.79, spec. 0.55, OR 4.5, CI 1.6 – 12.8) than mismatch TTP or MTT or stroke MRI interpretation by on call staff members.

Within 6 hours after onset real-time, prospective assessment of lesion growth by stroke MRI is difficult. Without time-consuming post processing, CBF and CBV maps improve the prognostic value of stroke MRI. A proximal occlusion has substantial impact on lesion growth and should be considered before thrombolysis.

Kucinski, T, Goebell, E, Höltje, J, Fiehler, J, Geisler, B, Wittkugel, O, Väterlein, O, Thomalla, G, Röther, J, Zeumer, H, et al, , Real-time Assessment of Lesion Growth in Acute Stroke MRI.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4403447.html