Methods and systems are provided for medical imaging systems. In one embodiment, a method comprises estimating an external scatter contamination in emission data based on an estimated emission activity originating from anatomies outside a field-of-view (FOV) of a scanner, the anatomies identified based on an image segmentation analysis performed on an image generated in the imaging system, the image generated prior to acquiring the emission data. In this way, a scatter correction applied to the emission data may include both scatter originating within the FOV and outside the FOV, and hence may be more accurate.