A method for determining a stage of fibrosis in a liver is disclosed. The method comprises the steps of: (1a) obtaining input data relating to the liver, the input data being generated using a second harmonic generation based imaging system (1 b) identifying a plurality of morphological features of the liver from the input data relating to the liver (1 c) generating a plurality of measurements based on the identified plurality of morphological features and (1d) determining the stage of fibrosis in the liver based, on the generated plurality of measurements.