A New Methodology of Viewing Extra-Axial Fluid and Cortical Abnormalities in Children with Autism via Transcranial Ultrasonography.
BACKGROUND
Autism spectrum disorders (ASDs) are developmental conditions of uncertain etiology which have now affected more than 1% of the school-age population of children in many developed nations. Transcranial ultrasonography (TUS) via the temporal bone appeared to be a potential window of investigation to determine the presence of both cortical abnormalities and increased extra-axial fluid (EAF).


METHODS
TUS was accomplished using a linear probe (10-5 MHz). Parents volunteered ASD subjects (N = 23; males 18, females 5) for evaluations (mean = 7.46 years ± 3.97 years), and 15 neurotypical siblings were also examined (mean = 7.15 years ± 4.49 years). Childhood Autism Rating Scale (CARS2(®)) scores were obtained and the ASD score mean was 48.08 + 6.79 (Severe).


RESULTS
Comparisons of the extra-axial spaces indicated increases in the ASD subjects. For EAF we scored based on the gyral summit distances between the arachnoid membrane and the cortical pia layer (subarachnoid space): (1) <0.05 cm, (2) 0.05-0.07 cm, (3) 0.08-0.10 cm, (4) >0.10 cm. All of the neurotypical siblings scored 1, whereas the ASD mean score was 3.41 ± 0.67. We also defined cortical dysplasia as the following: hypoechoic lesions within the substance of the cortex, or disturbed layering within the gray matter. For cortical dysplasia we scored: (1) none observed, (2) rare hypoechogenic lesions and/or mildly atypical cortical layering patterns, (3) more common, but separated areas of cortical hypoechogenic lesions, (4) very common or confluent areas of cortical hypoechogenicity. Again all of the neurotypical siblings scored 1, while the ASD subjects' mean score was 2.79 ± 0.93.


CONCLUSIONS
TUS may be a useful screening technique for children at potential risk of ASDs which, if confirmed with repeated studies and high resolution MRI, provides rapid, non-invasive qualification of EAF, and cortical lesions.
Newport Brain Research Laboratory , Newport Beach, CA , USA ; Brain Treatment Center , Newport Beach, CA , USA ; Brain Treatment Center , Buford, GA , USA.
James Jeffrey
JJ
Bradstreet
Department of Experimental and Clinical Medicine, University of Florence , Florence , Italy.
Stefania
S
Pacini
Department of Experimental and Clinical Biomedical Sciences, University of Florence , Florence , Italy ; Immuno Biotech Ltd., Saint Peter Port , Guernsey.
Marco
M
Ruggiero
autism spectrum disorders; cerebral spinal fluid; cortical dysplasia; extra-axial fluid; transcranial ultrasound