Qualitative Assessment of Perfusion Maps Derived from Pulsed Arterial Spin Labeling Magnetic Resonance Imaging (PASL MRI) in Patients with Cognitive Disorders

Background: Dementia and its most common cause, Alzheimer's disease (AD), are growing health problems worldwide. In the pathological process, before the emergence of symptoms, magnetic resonance imaging (MRI) may be used as a non-invasive method for measuring brain perfusion. Objectives: This study aimed to investigate the feasibility and variability of brain perfusion maps derived from pulsed arterial spin labeling (PASL) MRI in a heterogeneous group of patients with cognitive disorders. Patients and Methods: In this cross-sectional study, 85 out of 134 patients with cognitive disorders, including 23 cases of AD, 24 cases of mild cognitive impairment (MCI), 31 cases of depression, and seven cases of subjective memory impairment (SMI), were considered eligible for the study. All patients were evaluated qualitatively with 3D PASL sequences, using inline cerebral blood flow (CBF) maps. Mental examinations and neuropsychological tests were also performed beforehand. Results: Based on the CBF maps, bilateral parietal hypoperfusion was significant in the AD and MCI groups (83 and 67%, respectively), compared to patients with depression or SMI (P < 0.01). However, it was significantly low in depressed patients (13%), and there was no hypoperfusion in the SMI group. There was a good interobserver agreement, based on the kappa coefficient in all groups (0.78%; 95% CI: 0.65 - 0.91). Conclusion: The PASL MRI technique can be valuable for evaluating cognitive disorders, as it is non-invasive, rapid, and easily accessible. Besides, the qualitative assessment of CBF maps using this technique is reproducible and feasible in routine clinical practice.