CT-perfusion time-maps likely disclose the earliest imaging signs of posterior reversible encephalopathy syndrome (PRES)

CT perfusion in acute stroke calls: A pictorial review and differential diagnoses

“…Although the process is classically described as involving the parieto‐occipital regions, it has been known to involve all other cerebral regions, and may be assymetrical or unilateral. The perfusion patterns related to PRES are also inconsistent with variable MTT and CBV, but generally a reduced CBF has been described …”

Advanced Imaging Techniques in Diagnosis of Posterior Reversible Encephalopathy Syndrome (PRES)

“…Some studies have found hyperperfusion with increased cerebral blood flow (CBF), cerebral blood volume (CBV) and reduction in time to peak (TTP) and mean transit time (MTT) (17)(18)(19) (Figure 2). Other studies showed opposite results with vasoconstriction, reduction in CBF, near normal CBV, and increased in TTP, MTT, and time to drain (TTD) (20)(21)(22).…”

“…Although the abovementioned mechanisms can explain the underlying pathophysiology of vasculopathy in hypertension induced PRES, they cannot be generalized to all PRES cases as many of them present with normal or near normal blood pressure. A growing body of evidence suggests in clinical conditions presenting with PRES, there are similar systemic processes contributing to vasculopathy including activation of immune system, increased in cytokines and interleukins, endothelial damage with increased permeability, increased leukocyte adherence, and consequently microcirculatory dysfunction, focal vasoconstriction and vasodilatation and beading of the vessels and consequently tissue damage (21,29).…”

Advanced and Conventional Magnetic Resonance Imaging in Neuropsychiatric Lupus

“…The main parameters derived from them are mean transit time (MTT), time to peak (TTP), cerebral blood flow (CBF) and cerebral blood volume (CBV). The defined pathological patterns are hypoperfusion (high MTT/TTP, low CBF/CBV) and hyperperfusion (low TTP/MTT, high CBV/CBF) 87 . Few prospective studies analyzed brain perfusion in SLE patients.…”