Magnetic resonance imaging and its applications in morphological studies of pinnipeds

The Saimaa ringed seal (Phoca hispida saimensis) is an endangered endemic subspecies of Lake Saimaa, Finland. Due to its threatened status, the morphology and physiology of the subspecies cannot be studied using live individuals. Magnetic resonance imaging (MRI) is an accurate research method to study normal anatomy and pathology of the subspecies. A female seal cadaver was examined with MRI in three orientations. Morphological structures were identified and verified by reference slice sectioning and dissection. The results provide a morphological MRI reference database for ringed seals and for other pinnipeds. Moreover, pathological and possibly infectious lesions were visible in the blubber and in the apex of the lung. In addition to morphological studies of pinnipeds, MRI can supplement conventional autopsies.