Cerebral perfusion disturbances in traumatic brain injury: A preliminary study about direct and indirect effects on memory and psychoemotional outcome

Eleftherios Kavroulakis ,Panagiotis G Simos ,Antonios Vakis ,Dimitra Karageorgou ,Styliani Papadopoulou ,Stelios Demetriou ,Efrosini Papadaki

doi:10.36162/hjr.v1i1.22

Abstract

Purpose: To investigate possible associations between hemodynamic changes and psychoemotional/cognitive status in patients with chronic traumatic brain injury (TBI). Methods and Materials: Dynamic Susceptibility Contrast Magnetic Resonance Imaging (DSC MRI) perfusion technique was applied to 22 patients with chronic TBI and 21 healthy volunteers. Patients were divided into moderate/severe and mild TBI groups, according to clinical syndromes, and administered episodic memory tests and self-report measures of anxiety and depression symptoms. Cerebral blood flow (CBF) and cerebral blood volume (CBV) values were measured in normal appearing white matter (NAWM) and normal appearing deep gray matter (NADGM) regions bilaterally, including those involved in episodic memory and psychoemotional status. Results: The two TBI subgroups differed significantly on episodic memory indices. Significantly reduced CBV and CBF values were detected in the moderate/severe TBI group compared to controls ( p <0.001) in bilateral temporal, right frontal and left parietal NAWM and the semioval center. Perfusion reduction in the mild TBI group reached significance, compared to controls, only in the left temporal WM ( p <0.002). Substantial negative correlations were found between depression/anxiety scores and CBV values in the mesial temporal lobes (MTL) bilaterally. Mediated regression models indicated that the effect of reduced CBV in the right MTL on verbal episodic memory was mediated by increased anxiety symptomatology. Conclusion: Patients with moderate/severe chronic TBI displayed widespread reductions in NAWM CBF and CBV. However, only MTL reduced CBV was associated with verbal episodic memory deficits and increased psychiatric symptomatology. Mediated regression results were consistent with indirect effects of reduced CBV on episodic memory capacity through increased anxiety symptoms.

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