Cerebral hypoperfusion in autism spectrum disorder

Abstract

Cerebral hypoperfusion, or insufficient blood flow in the brain, occurs in many areas of the brain in patients diagnosed with autism spectrum disorder (ASD). Hypoperfusion was demonstrated in the brains of individuals with ASD when compared to normal healthy control brains either using positron emission tomography (PET) or single-photon emission computed tomography (SPECT). The affected areas include, but are not limited to the: prefrontal, frontal, temporal, occipital, and parietal cortices; thalami; basal ganglia; cingulate cortex; caudate nucleus; the limbic system including the hippocampal area; putamen; substantia nigra; cerebellum; and associative cortices. Moreover, correlations between symptom scores and hypoperfusion in the brains of individuals diagnosed with an ASD were found indicating that the greater the autism symptom pathology, the more significant the cerebral hypoperfusion or vascular pathology in the brain. Evidence suggests that brain inflammation and vascular inflammation may explain a part of the hypoperfusion. There is also evidence of a lack of normal compensatory increase in blood flow when the subjects are challenged with a task. Some studies propose treatments that can address the hypoperfusion found among individuals diagnosed with an ASD, bringing symptom relief to some extent. This review will explore the evidence that indicates cerebral hypoperfusion in ASD, as well as the possible etiological aspects, complications, and treatments.

Rational use of mesenchymal stem cells in the treatment of autism spectrum disorders

“…Only a few adverse events (including seizures and hyperactivity) were observed, and these were controlled with medications[181]. It has been reported that cerebral hypoperfusion or insufficient blood flow in the brain occurs in many brain regions in ASD[182], and interestingly, their study suggested that the cell transplantation may have had a balancing effect on the brain metabolism[181]. Comparative Positron Emission Tomography-Computed Tomography scans before and 6 mo after cell transplantation showed increased 18 F-fluorodeoxyglucose uptake in the areas of frontal lobe, cerebellum, amygdala, hippocampus, parahippocampus, and mesial temporal lobe[181].…”

Stem cell therapy in autism: recent insights

“…Hypoperfusion has been recently demonstrated in key brain areas of ASD subjects. 89 Hypometabolic areas before cell transplantation showed increased metabolism after cellular delivery, probably due to improved oxygenation and functioning of the damaged neurons. As limitations, authors report the small sample size, and the absence of randomization and a control group.…”

The Relationship between Carotid Doppler Ultrasound and EEG Metrics in Healthy Preschoolers and Adults

“…In particular, the cortical hemodynamic responses in children with ADHD has been associated with working memory deficits [ 7 ]. Significantly higher regional cerebral blood flow (rCBF) values have been detected throughout the frontal white matter and subcortical gray matter in subjects with ASD [ 8 , 9 ]. These parameters were lowered with increasing IQ in a typically developing control group; such a correlation was absent in participants with ASD whose values were elevated across all IQ levels [ 10 ].…”