Brain Perfusion in Autism Varies with Age

Abstract

Oursubjects consisted of 14 autistic individuals and 14 controls ranging in age from 3 to 37 years. A ^99mTc HMPAO single photon emission computed tomogram (SPECT) was used to examine blood flow variations between autistic subjects, compared to an age- and gender-matched control group. We found significant hypoperfusion in the prefrontal areas of autistic individuals as compared to normals in every case (p < 0.01). As the age of the autistic individuals increased the hypoperfusion of verbal-associated areas in the left temporal lobe and frontal areas became more evident. The findings were significant at the p < 0.001 level. The changes in perfusion over time correlated with language development and acquisition as individuals matured. We conclude that autistic individuals have a deficiency in prefrontal areas associated with word identification and language formation skills. This subsequently prevents development of true verbal fluency and development in the temporal and frontal areas associated with speech and communication.

Hyperbaric oxygen therapy may improve symptoms in autistic children

“…It is possible that HBOT in younger autistic children can improve cerebral oxygenation and thus overcome the effects of hypoperfusion and aid these children in ''catching up'' with their neurotypical peers. Furthermore, the younger children in this case series may have had less overall hypoperfusion to surmount because decreased cerebral blood flow to areas associated with communication has been shown to worsen with increasing age in autistic children [27]. It is likely that the older children in this case series need more than 40 HBOT sessions to show further improvements, especially since some HBOT researchers have noted that 50-80 HBOT sessions are typically needed to show significant clinical gains [79].…”

“…Multiple independent single photon emission computed tomography (SPECT) and positron emission tomography (PET) research studies have demonstrated hypoperfusion to several areas of the autistic brain, most notably the temporal lobes [26][27][28][29][30][31][32][33][34][35][36][37][38][39]. Several studies show that reduced blood flow to the temporal regions and other brain areas correlates with many of the clinical findings associated with autism including repetitive, self-stimulatory and stereotypical behaviors, and impairments in communication, sensory perception, and social interaction [27,29,31,[39][40][41][42]. Furthermore, a correlation between decreased IQ and hypoperfusion of the temporal and frontal lobes has been described in autistics [36].…”

“…This diminished perfusion correlated with decreased language development. The authors concluded that hypoperfusion ''subsequently prevents development of true verbal fluency and development in the temporal and frontal areas associated with speech and communication'' [27].…”

Plasticity of nonneuronal brain tissue: Roles in developmental disorders

“…Their observation is consistent with reports of morphological abnormalities in the caudate nucleus [Reiss et al, 1995] and frontostriatal pathways [Barnea-Goraly et al, 2003] of individuals with FXS. In blood flow studies of autistic subjects, hypoperfusion have been identified in several brain areas, including the prefrontal, frontal, and temporal cortices [Hashimoto et al, 2000;Wilcox et al, 2002;Zilbovicius et al, 2000].…”

Functional SPECT neuroimaging using machine learning algorithms distinguishes autism spectrum disorder from healthy subjects

“…Since 1992, there have been many studies using SPECT and PET imaging, totaling over 900 ASD patients. The findings have primarily shown lower perfusion in the prefrontal cortex, temporal lobes, parietal lobes and cerebellum, compared to controls [38][39][40][41][42][43]. However, most of the individual studies had small sample sizes and none closely examined the potential sensitivity and specificity of using SPECT or PET as a diagnostic tool to distinguish between healthy and non-ASD patient controls.…”