1. ROI MEASUREMENT OF MIDDLE CEREBRAL ARTERY: IS IT A PRIMARY SIGN OF INFARCTION? G. PANAGI, M. KASTANIA, I. MARKAKI^, N. STROUMBAKIS, S. FONDARA, E. SGORA, E. PANOURGIAS*, S. CHALKIAS Radiology Dept. Gen. Hospital of Chios Island, *Radiology Dept. Areteion Hospital Univ. of Athens, ^National Institute of Statistics, Athens, Greece L. KOULAI^, G. DOUNIAS* ^Dept. of Statistics, Athens University of Economics and Business, Athens, Greece *Management & Decision Engineering Laboratory (MDE-Lab), Department of Financial & Management Engineering, University of the Aegean, Chios, Greece XIX Symposium Neuroradiologicum, Bologna, Italy, October 4-9, 2010

2. Fundamental Question In patients with stroke, can ROI measurement of MCA be used as an additional primary sign of infarction, even if other primary signs are absent? XIX Symposium Neuroradiologicum, Bologna, Italy, October 4-9, 2010

3. Materials & methods Our work (100 patients) progressed since January 2010 and the new eXceldatabase consists of 465 patients admitted in the Emergencies within 6h from the beginning of neurological symptoms underwent NE Brain CT scan

4. Materials & methods 2 polygonal ROIs were drawn on each M1 segment of both MCAs Automatic calculation of HU density Volume Surface was generated

5. Materials & methods Also recorded: Age (mean: 75y), CT findings (including hyperdense appearance of MCA and insular ribbon sign), neurological findings Advanced Statistical tools for data elaboration

6. Statistical Analysis and results Patients with R (or L) HEMIPLEGIA, had higher values of ROI L MCA > ROI R MCA at 95% confidence interval of difference (or ROI R MCA > ROI L MCA) Usual primary signs, appearance L: 15% insular ribbon, 16% hyperdense MCA (R: 19%, 16%)

7. Statistical Analysis and results Patients with a hypodense area on L (or R) hemisphere in brain CT had higher values of ROI L MCA>ROI R MCA, at 95%confidence intrval of the difference (or ROI R MCA>ROI L MCA respectively)

8. More Questions Is there a cut-off point of ROI values (ex. ROI> …) comparable to the neurological or CT findings? Is there an absolute difference value of ROIs (ROI R MCA – ROI L MCA) suggestive of significant difference related to symptoms?

9. …more statistical analysis and results ROI R MCA>47.5 HU correlated with hypodense area in rmca territory in CT (respectively for LMCA) ROI LMCA>47.5 HU correlated with R HEMIPLEGIA Mean value ROI RMCA= 45.39 HU ROI LMCA= 45 HU

10. … more statistical analysis and results Values of the absolute difference of ROI RMCA – ROI LMCA >3.5 HU are “suggestive” of L HEMIPLEGIA (with 95% predictive value)

11. Conclusions and more to do…   ROI measurement of MCA seems promising as an additional primary sign of stroke   Easy to apply and interpret during the CT scan, serves the rule “time is brain”   Although primary signs of stroke have been reported since the ‘80s (Stroke 1983;14;756-762), the ROI measurement of MCA was reported in (Cerebrovasc Dis 10:419-423, 2000), (AJNR 2005; 26:2027- 2029) to describe the “hyperdense” and “hypodense artery sign” respectively.   Larger series of data and more advanced Computational Intelligence tools, will provide more confident results