Refresh a georeferenced image after modifying its worldfile

I have several raster layers which each layer is created from an image and its worldfile for georefencing.
I want to refresh the layers after changing the world files.
I have tried the code below but it does not refresh the image layer.
The image layers stay unchanged.
I am using QGIS 3.2.3. The code below is developed for a plugin.

# get the active layer
selected_layer = self.iface.mapCanvas().layers()
for layer in selected_layer:
    layer.setCacheImage(None)
    layer.dataProvider().reloadData()
    layer.triggerRepaint()