Postmortem MRI detection of a dentate nucleus lesion of uncertain significance in a death with suspected heat exposure

The forensic diagnosis of heat-related death remains challenging when objective pathological indicators are absent. We report a case in which circumstantial and environmental investigative information raised suspicion of heat exposure, although classical autopsy findings associated with heatstroke, such as marked elevation of rectal temperature or renal myoglobin casts, were not identified. Postmortem computed tomography revealed no apparent intracranial abnormalities. In contrast, postmortem magnetic resonance imaging demonstrated a focal abnormality surrounding the cerebellar dentate nucleus that was not detectable on CT. Histopathological examination of the corresponding region revealed the presence of hemosiderin-laden macrophages. The temporal relationship and etiological significance of this lesion could not be determined, and a causal association with heat exposure could not be established. Nevertheless, the discrepancy between postmortem CT and MRI findings in this case indicates that certain cerebellar abnormalities may only be recognizable by MRI. These findings underscore the complementary role of postmortem MRI in forensic investigations, particularly for documenting subtle intracranial changes in cases where the cause of death remains uncertain. Further accumulation of similar cases is necessary to clarify the forensic relevance of dentate nucleus abnormalities and to determine whether such findings have diagnostic or supportive value in suspected heat-related deaths.