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CPS2131 Philip L.H. Yu et al.
                  Our deep learning model used Adam optimizer with 1e-5 initial learning rate
                  and trained on 200 epochs with Tesla K80 GPU.
                     To  evaluate  the  performance  of  the  deep  learning  architecture  in
                  segmenting  the  hyperdense  MCA  dot  signs,  the  dice  similarity coefficients
                  (DSC)  is  utilized  as  the  evaluation  metric  for  goodness  of  fit.    The  DSC  is
                  defined as
                                                       2| ∩ |
                                                 =
                                                       || + ||
                  where  A  and  B  represent  the  regions  of  all  voxels  of  ground  truth  and
                  segmentation respectively.




































                                         Fig. 4. Deep Learning Architecture

                  4.  Result
                     Within 150 CT scans, 74 patients were diagnosed to have hyperdense MCA
                  dot sign and the rest were empty. Among the 74 positive MCA sign subjects,
                  63 were within training and the rest 11 were in the testing. As shown in Table
                  1, patients without side of weakness do not have MCA dot sign; thus the model
                  involved side of weakness and a filter to select the potential subjects might
                  have MCA. We subtract cropped bounding boxes within specified regions of
                  interest for each set of CT scans. If patient suffer side of weakness, we extract
                  his or her ROI within corresponding left or right hemisphere; if patient suffer
                  both  side  of  weakness,  we  use  both  ROIs  in  two  hemispheres;  otherwise,


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