A Study Comparing SPECT and MRI in Patients With Anosmia After Traumatic Brain Injury

Abstract

PURPOSE: The initial or first clinical presentation of altered sensation of smell is directly linked to the degree of impaired sensitivity. We took the opportunity to examine normal and nonspecific MRI findings in 6 patients with known anosmia after traumatic brain injury with perfusion SPECT brain imaging. MATERIAL AND METHODS: Patients included those with primary loss of smell after head injury. All patients underwent standard testing by the Taste & Smell Center. Normal or nonspecific near normal brain MRI studies were subsequently referred for SPECT perfusion neuroimaging. RESULTS: MRI studies were negative in 3 cases. In the remaining studies, one case showed nonspecific white matter change, another low signal in the left frontal gyrus, and the sixth case merely some cortical atrophy. All 6 cases demonstrated lesions on SPECT involving the frontal, temporal, and temporoparietal cortex. CONCLUSION: This study identified altered blood perfusion pattern in otherwise normal anatomic structures on MRI.