A computer implemented method comprising the steps of: generating a first parametric map (240, 250), the first parametric map being based upon at least a portion of each of at least two optoacoustic images (205, 210); each of the at least two optoacoustic images reflecting at least a portion of an optoacoustic response of a volume of tissue to a different light event, at least one of the different light events having a first predominant wavelength which is shorter than a second predominant wavelength of at least a second of the different light events; wherein each of the at least two optoacoustic images is based on a sinogram, each sinogram comprising sampled data, corresponding to the respective light event, in which each sample is normalized by dividing it by a value proportional to a measured energy of the light event; the first parametric map being reflective of areas within at least a portion of the volume of tissue, which areas have a difference in absorption in response to the longer second wavelength light event compared to the shorter first wavelength light event; generating a second parametric map (240, 255), the second parametric map being based upon the at least a portion of the each of at least two optoacoustic images (205, 210); the second parametric map being reflective of areas within the at least a portion of the volume of tissue having stronger absorption in response to the longer second and shorter first wavelength light events than other areas within the at least a portion of the volume of tissue; wherein the first parametric map is an oxygenation map and the second parametric map is a hemoglobin map; generating a mask reflective of a combination of the oxygenation map and the hemoglobin map, the mask used to exclude areas of an image; generating a masked parametric map (750, 260) by applying the mask to an auxiliary map, thus forming a new parametric map, the auxiliary map being selected from the group consisting of: the first parametric map, the second parametric map, and an image, wherein the image relates to the at least a portion of the volume of tissue; and outputting the masked parametric map. generating a first parametric map (240, 250), the first parametric map being based upon at least a portion of each of at least two optoacoustic images (205, 210); each of the at least two optoacoustic images reflecting at least a portion of an optoacoustic response of a volume of tissue to a different light event, at least one of the different light events having a first predominant wavelength which is shorter than a second predominant wavelength of at least a second of the different light events; wherein each of the at least two optoacoustic images is based on a sinogram, each sinogram comprising sampled data, corresponding to the respective light event, in which each sample is normalized by dividing it by a value proportional to a measured energy of the light event; the first parametric map being reflective of areas within at least a portion of the volume of tissue, which areas have a difference in absorption in response to the longer second wavelength light event compared to the shorter first wavelength light event; each of the at least two optoacoustic images reflecting at least a portion of an optoacoustic response of a volume of tissue to a different light event, at least one of the different light events having a first predominant wavelength which is shorter than a second predominant wavelength of at least a second of the different light events; wherein each of the at least two optoacoustic images is based on a sinogram, each sinogram comprising sampled data, corresponding to the respective light event, in which each sample is normalized by dividing it by a value proportional to a measured energy of the light event; the first parametric map being reflective of areas within at least a portion of the volume of tissue, which areas have a difference in absorption in response to the longer second wavelength light event compared to the shorter first wavelength light event; generating a second parametric map (240, 255), the second parametric map being based upon the at least a portion of the each of at least two optoacoustic images (205, 210); the second parametric map being reflective of areas within the at least a portion of the volume of tissue having stronger absorption in response to the longer second and shorter first wavelength light events than other areas within the at least a portion of the volume of tissue; wherein the first parametric map is an oxygenation map and the second parametric map is a hemoglobin map; the second parametric map being reflective of areas within the at least a portion of the volume of tissue having stronger absorption in response to the longer second and shorter first wavelength light events than other areas within the at least a portion of the volume of tissue; wherein the first parametric map is an oxygenation map and the second parametric map is a hemoglobin map; generating a mask reflective of a combination of the oxygenation map and the hemoglobin map, the mask used to exclude areas of an image; generating a masked parametric map (750, 260) by applying the mask to an auxiliary map, thus forming a new parametric map, the auxiliary map being selected from the group consisting of: the first parametric map, the second parametric map, and an image, wherein the image relates to the at least a portion of the volume of tissue; and outputting the masked parametric map.