RT Journal Article
SR Electronic
T1 Functional imaging of cerebral reorganization in mild traumatic brain injury (MTBI) with cognitive fatigue
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 173P
OP 173P
VO 48
IS supplement 2
A1 Swan, Megan
A1 Stobbe, Gary
A1 Uomoto, Jay
A1 Minoshima, Satoshi
A1 Djang, David
A1 Krishnananthan, Ruben
A1 Lewis, David
YR 2007
UL http://jnm.snmjournals.org/content/48/supplement_2/173P.2.abstract
AB 587 Objectives: Purpose was to investigate alterations in regional brain activity in patients with MTBI complaining of cognitive fatigue in comparison to healthy control (HC) during the Paced Auditory Serial Addition Task (PASAT). Methods: Eleven MTBI patients, (82% female, 18% male, mean age of 42.36 years), with mean 33.2 months post-injury, and 15 HC(80% f, 20% m, mean age 44.4 yrs) had 2 SPECT scans: resting and PASAT-activated. For activation, subjects were injected with 30 mCi Tc-99m bicisate during PASAT, a complex measure of divided attention and processing speed. Following image registration and pixel normalization, pair-wise subtractions were conducted between resting and activated scans and averaged across participants. Areas of significant changes were accessed by controlling multiple comparisons at Type I error rate of 0.05 (Z=4.0). Results: Similar activation occurred in right insular and right medial frontal cortex, for both MTBI and HC during PASAT. HC demonstrated activation in left dorsolateral prefrontal cortex, right superior temporal gyrus, left posterior thalamus/fornix, and right cerebellum not seen in MTBI. MTBI showed activation in left medial frontal gyrus, not exhibited in HC and, most notably, no activation in cerebellum. Conclusions: In HC focal activation occurred in frontal, temporal, and cerebellar regions in PASAT, whereas MTBI primarily had diffuse activation in frontal regions. HC activated other brain regions responsible for information processing, inhibition of automatic responses, spatial mapping, and verbal working memory, which may represent a network of brain regions needed to efficiently complete PASAT. MTBI lack of activation in the cerebellum suggests the dysfunction of working memory, or the inability to efficiently process and verbally respond to paced information in the test.