Effect of incomplete (spontaneous and postthrombolytic) recanalization after middle cerebral artery occlusion: a magnetic resonance imaging study.
OBJECTIVE
Early reperfusion is one of the best predictors of good outcome after acute middle cerebral artery (MCA) occlusion. The purpose of this study was to analyze the frequency and relevance of incomplete recanalization for tissue and clinical outcome.


METHODS
From a larger acute stroke database (Kompetenznetzwerk Schlaganfall B5), all patients (n=82) with MCA main stem occlusion (excluding carotid T-occlusions) were selected. These patients had received a multiparametric stroke MRI protocol including diffusion- and perfusion-weighted imaging (DWI, PWI) and MR angiography (MRA) within 6 hours after symptom onset, at day 1 and after 1 week. Recanalization status was determined with MRA on day 1 (according to Thrombolysis In Myocardial Infarction flow grades) and used to group patients into those with persistent occlusion (0) or minimal (1), partial (2), or complete (3) recanalization.


RESULTS
Incomplete recanalization according to MRI criteria was found in 39 patients (grade 1: n=20; grade 2: n=19), complete recanalization in 10, and persistent occlusion in 33. There was no statistically significant difference in any of the clinical (National Institutes of Health Stroke Scale score) or MRI baseline parameters (DWI lesion, PWI deficit, mismatch volume, mismatch ratio). However, lesion growth was smaller in patients with recanalization (even in patients with only minimal recanalization) and outcome was related to the degree of recanalization (mean modified Rankin score at 90 days: 3.36, 2.70, 1.79, and 1.44 for the groups with no, minimal, partial, and complete recanalization, respectively). Both incomplete and complete recanalization was more frequent in patients receiving thrombolysis.


CONCLUSIONS
Incomplete recanalization on day 1 is a frequent MR finding after MCA main stem occlusion, indicating a more favorable clinical course than persistent occlusion. MR indicators of early recanalization could be useful surrogates of efficacy in thrombolytic trials.
Neumann-Haefelin
T
T
Department of Neurology, University Hospitals, Frankfurt, Germany. tnh@rz.uni-frankfurt.de
du Mesnil de Rochemont
R
R
Fiebach
J B
JB
Gass
A
A
Nolte
C
C
Kucinski
T
T
Rother
J
J
Siebler
M
M
Singer
O C
OC
Szabo
K
K
Villringer
A
A
Schellinger
P D
PD
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016208:Databases, Factual; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000706:statistics & numerical data; D020244:Infarction, Middle Cerebral Artery / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D018810:Magnetic Resonance Angiography / Q000706:statistics & numerical data; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000187:drug effects* / Q000503:physiopathology; D020127:Recovery of Function / Q000187:drug effects*; D012075:Remission, Spontaneous; D012189:Retrospective Studies; D012720:Severity of Illness Index; D017211:Treatment Failure; D016896:Treatment Outcome; D014654:Vascular Patency / Q000187:drug effects*
D005343:Fibrinolytic Agents