Post-traumatic atrophy of the olfactory tract: clinicopathological features

We present the clinicopathological features of a 51-year-old male patient with post-traumatic atrophy of the olfactory bulb and tract, and additional contusion on the base of the temporal lobe. Prior to death, there was no clinical evidence of an impaired olfactory function; the lesions were identified during post-mortem evaluation. Macroscopically, the left olfactory tract appeared to be substantially diminished in volume, whereas the right olfactory tract could not be identified within the markedly fibrotic leptomeninges in the fronto-orbital region. Postmortem MRI examination of the brain demonstrated superficial defects in the fronto-orbital cortex on the right side, corresponding to the region of the atrophic olfactory tract. Microscopic examination revealed degenerative changes with reactive gliosis and a large amount of corpora amylacea most pronounced in the right olfactory tract. The pathophysiologic mechanisms of olfactory degeneration after head trauma are discussed.