Potential Neuroimaging Biomarkers for Autism Spectrum Disorder: A Comprehensive Review of MR Imaging, fMR Imaging, and PET Studies.

Autism spectrum disorder (ASD) is a characteristically heterogeneous disorder, as multiple neurodevelopmental disorders are characterized by similar symptomology and behavior. Research has shown that individuals with ASD benefit from early intervention; neuroimaging data may reveal information that cannot be obtained from traditional behavioral analysis. This review discusses the use of structural MR imaging, functional MR imaging (fMR imaging), and PET in the detection of ASD.

Applications of PET and SPECT in Patients with Autism Spectrum Disorder.

Autism spectrum disorder (ASD) consists of neurological development disorders that manifest before three years of age and affect social interactions, markedly restricting range of interests and activities, often associated with some degree of intellectual disability. Single-photon emission computed tomography (SPECT) and positron emission tomography (PET) are non-invasive imaging tools to investigate the function of the brain in vivo. SPECT and PET studies exploring rCBF and brain glucose metabolism in patients with ASD have been performed, providing important insights into the brain regions involved in ASD.

The glial perspective of autism spectrum disorder convergent evidence from postmortem brain and PET studies.

Objective: The present study aimed to systematically and quantitatively review evidence derived from both postmortem brain and PET studies to explore the pathological role of glia induced neuroinflammation in the pathogenesis of ASD, and discuss the implications of these findings in relation to disease pathogenesis and therapeutic strategies.

Method: An online databases search was performed to collate postmortem studies and PET studies regarding glia induced neuroinflammation in ASD as compared to controls. Two authors independently conducted the literature search, study selection and data extraction.

Lower Availability of Mitochondrial Complex I in Anterior Cingulate Cortex in Autism: A Positron Emission Tomography Study.

Objective: Mitochondrial dysfunction has been implicated in the pathophysiology of autism spectrum disorder (ASD) in previous studies of postmortem brain or peripheral samples. The authors investigated whether and where mitochondrial dysfunction occurs in the living brains of individuals with ASD and to identify the clinical correlates of detected mitochondrial dysfunction.

Methods: This case-control study used positron emission tomography (PET) with 2--butyl-4-chloro-5-{6-[2-(2-[F]fluoroethoxy)-ethoxy]-pyridin-3-ylmethoxy}-2H-pyridazin-3-one ([F]BCPP-EF), a radioligand that binds to the mitochondrial electron transport chain complex I, to examine the topographical distribution of mitochondrial dysfunction in living brains of individuals with ASD.

Emotion Facial Processing in Children With Autism Spectrum Disorder: A Pilot Study of the Impact of Service Dogs.

Processing and recognizing facial expressions are key factors in human social interaction. Past research suggests that individuals with autism spectrum disorder (ASD) present difficulties to decode facial expressions. Those difficulties are notably attributed to altered strategies in the visual scanning of expressive faces.

Brain 18F-FDG PET in Cowden Syndrome.

Cowden disease is associated with neurodevelopmental abnormalities such as macrocephaly, autism spectrum disorder, and developmental delay. Our understanding of neuroimaging anomalies in patients with PTEN mutations is limited to anatomical MRI abnormalities including white matter abnormalities, meningiomas, arteriovenous malformations, and cortical dysplasia. Our current communication extends the neurological Cowden syndrome phenotype by using brain 18F-FDG PET/CT imaging as a useful complementary approach to MRI to explore movement disorders and neuropsychiatric syndromes in a patient with Cowden disease.

Striatal dopamine synthesis capacity in autism spectrum disorder and its relation with social defeat: an [F]-FDOPA PET/CT study.

Alterations in dopamine signalling have been implied in autism spectrum disorder (ASD), and these could be associated with the risk of developing a psychotic disorder in ASD adults. Negative social experiences and feelings of social defeat might result in an increase in dopamine functioning. However, few studies examined dopamine functioning in vivo in ASD.

Microglia mediated neuroinflammation in autism spectrum disorder.

Background: Although the precise pathophysiologies underlying autism spectrum disorder (ASD) has not yet been fully clarified, growing evidence supports the involvement of neuroinflammation in the pathogenesis of this disorder, with microglia being particular relevance in the pathophysiologic processes.

Objective: The present review aimed to systematically characterize existing literature regarding the role of microglia mediated neuroinflammation in the etiology of ASD.

Methods: A systematic search was conducted for records indexed within Pubmed, EMBASE, or Web of Science to identify potentially eligible publications.

[C]PBR28 MR-PET imaging reveals lower regional brain expression of translocator protein (TSPO) in young adult males with autism spectrum disorder.

Mechanisms of neuroimmune and mitochondrial dysfunction have been repeatedly implicated in autism spectrum disorder (ASD). To examine these mechanisms in ASD individuals, we measured the in vivo expression of the 18 kDa translocator protein (TSPO), an activated glial marker expressed on mitochondrial membranes. Participants underwent scanning on a simultaneous magnetic resonance-positron emission tomography (MR-PET) scanner with the second-generation TSPO radiotracer [C]PBR28.