Displaying a dicom image in a matplotlib widget within a pyqt window. The axes have been set to not visible

imagedisplay

class MainWindow(QMainWindow, Ui_MainWindow):
    def __init__(self,parent=None):
        QDialog.__init__(self,parent)
        self.setupUi(self)
        self.mpl.canvas.ax.clear()
        ds=dicom.read_file("slice.dcm")

        #self.mpl.canvas.ax.imshow(self.image1, cmap=pylab.cm.bone)    
        self.mpl.canvas.ax.imshow(ds.pixel_array, cmap=pylab.cm.bone)
        self.mpl.canvas.ax.xaxis.set_visible(False)
        self.mpl.canvas.ax.yaxis.set_visible(False)
        self.mpl.canvas.draw()