Diffusion weighted imaging and estimation of prognosis using apparent diffusion coefficient measurements in ischemic stroke.
OBJECTIVE
Estimation of the prognosis of infarction by using diffusion weighted imaging (DWI) and quantitative apparent diffusion coefficient (ADC) measurements.


METHODS
23 patients having acute stroke symptoms with verified infarction in magnetic resonance imaging (MRI) were included in this study. Their MRI studies were performed between 6 and 12h after the onset of their symptoms and were repeated on the fifth day. The infarction volumes were calculated by using DWI and the patients were divided into two groups as the ones having an expansion in the infarction area (group 1, n=16) and the others having no expansion in the infarction area (group 2, n=7). Quantitative ADC values were estimated. The groups were compared in terms of the ADC values on ADC maps obtained from DWI, performed during the between 6 and 12h from the onset of the symptoms, referring to the core of the infarction (ADC(IC)), ischemic penumbra (ADC(P)) and the nonischemic parenchymal tissue (ADC(N)). P values<0.05 were accepted to be statistically significant.


RESULTS
During the between 6 and 12h mean infarction volume calculated by DWI was 23.3cm(3) for group 1 patients (ranging from 1.1 to 68.6) and this was found to be 40.3cm(3) (ranging from 1.8 to 91.5) on the fifth day. For the group 2 patients these values were found to be 42.1cm(3) (ranging from 1 to 94.7) and 41.9 (ranging from 1 to 94.7) for the same intervals respectively. A significant statistical result was failed to be demonstrated between the mean ADC(IC) and ADC(N) values (p=0.350 and p=0.229 respectively). However the comparison of the ADC(P) values between the groups was found to be highly significant (p<0.001). When the differences between the ADC(P) and ADC(IC) and ADC(N) and ADC(P) were compared the results proved to be statistically significant (p=0.038 and p<0.001 respectively).


CONCLUSIONS
We believe that ADC results that would be obtained from the core and the penumbra of the infarction area will be beneficial in the estimation of the infarction prognosis and in the planning of a treatment protocol.
Gonen
Korcan Aysun
KA
Department of Radiology, State Hospital, Eski Cami district, Hastane street, Tekirdag, Turkey. aysunbalc@yahoo.com
Simsek
Mehmet Masum
MM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D002545:Brain Ischemia / Q000150:complications* / Q000175:diagnosis*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D020521:Stroke / Q000150:complications* / Q000175:diagnosis*