A method of three-dimensional stereotactic surface projection, 3D SSP, of a PET/SPECT image of a brain generated using an amyloid imaging agent, said method comprising the steps of: (a) spatially normalizing the PET/SPECT image, wherein each voxel on the surface of the brain is registered to a standard space, and (b) calculating SSP for each surface voxel of the spatially normalized PET/SPECT image, wherein said calculating step further comprises calculating the maximum intensity along a line extending from each surface voxel and perpendicular to the surface into the tissue such that each line extends to a predefined maximum depth characterized in that said predefined maximum depth is calculated individually for each surface voxel; wherein the method further comprises the steps of: choosing an intensity threshold on an amyloid negative standard uptake value ratio, SUVR, average image computed as an average of amyloid negative healthy controls, in such way that the threshold corresponds to the boundary of gray and white matter as determined by using probabilistic gray and white matter masks for guidance; and assigning a maximum depth for each line from its corresponding surface voxel, the assigning step further comprising: determining a maximum depth limit and a minimum depth limit for each line; sampling along each line until either sampling a value larger than the threshold or the maximum depth limit has been reached, wherein: a) if a value larger than the threshold is found, the depth of where this value was found is assigned as the maximum depth for the line from the corresponding surface voxel; b) if no value larger than the threshold is found, the maximum depth limit is assigned as the maximum depth for the line from the corresponding surface voxel, and c) if a value larger than the threshold is found and its depth is less than the minimum depth limit, assigning the minimum depth limit as the maximum depth for the line from the corresponding surface voxel. (a) spatially normalizing the PET/SPECT image, wherein each voxel on the surface of the brain is registered to a standard space, and (b) calculating SSP for each surface voxel of the spatially normalized PET/SPECT image, wherein said calculating step further comprises calculating the maximum intensity along a line extending from each surface voxel and perpendicular to the surface into the tissue such that each line extends to a predefined maximum depth characterized in that said predefined maximum depth is calculated individually for each surface voxel; choosing an intensity threshold on an amyloid negative standard uptake value ratio, SUVR, average image computed as an average of amyloid negative healthy controls, in such way that the threshold corresponds to the boundary of gray and white matter as determined by using probabilistic gray and white matter masks for guidance; and assigning a maximum depth for each line from its corresponding surface voxel, the assigning step further comprising: determining a maximum depth limit and a minimum depth limit for each line; sampling along each line until either sampling a value larger than the threshold or the maximum depth limit has been reached, wherein: a) if a value larger than the threshold is found, the depth of where this value was found is assigned as the maximum depth for the line from the corresponding surface voxel; b) if no value larger than the threshold is found, the maximum depth limit is assigned as the maximum depth for the line from the corresponding surface voxel, and c) if a value larger than the threshold is found and its depth is less than the minimum depth limit, assigning the minimum depth limit as the maximum depth for the line from the corresponding surface voxel. determining a maximum depth limit and a minimum depth limit for each line; sampling along each line until either sampling a value larger than the threshold or the maximum depth limit has been reached, wherein: a) if a value larger than the threshold is found, the depth of where this value was found is assigned as the maximum depth for the line from the corresponding surface voxel; b) if no value larger than the threshold is found, the maximum depth limit is assigned as the maximum depth for the line from the corresponding surface voxel, and c) if a value larger than the threshold is found and its depth is less than the minimum depth limit, assigning the minimum depth limit as the maximum depth for the line from the corresponding surface voxel. a) if a value larger than the threshold is found, the depth of where this value was found is assigned as the maximum depth for the line from the corresponding surface voxel; b) if no value larger than the threshold is found, the maximum depth limit is assigned as the maximum depth for the line from the corresponding surface voxel, and c) if a value larger than the threshold is found and its depth is less than the minimum depth limit, assigning the minimum depth limit as the maximum depth for the line from the corresponding surface voxel.