Rahul Shantikumar Chivate MBBS, Presenter: Nothing to Disclose

Palak Thakrar, Abstract Co-Author: Nothing to Disclose

Jayant Narang MD, Abstract Co-Author: Nothing to Disclose

Deepak Patkar MD, Abstract Co-Author: Nothing to Disclose

Susheel Kumar, Abstract Co-Author: Nothing to Disclose

Mitusha Verma, Abstract Co-Author: Nothing to Disclose

There is no specific marker to diagnose autism. Morphologically brain shows no abnormalities on imaging studies. However PET CT can determine the uptake of cerebral blood flow and with help of standard uptake value, areas of hypoperfusion can be quantitatively mapped. 

23 autistic patients with DSM-IV TR diagnostic criteria, pre stem cell were included in this study. Youngest patient was 3 years old and oldest was 26 years. Two patients were adults with age 20 and 26 years. Neuro PET scan was performed after 1 hour of injection of 7 mCi of 18 FDG. Images were obtained on 64 slice CT and PET system based third generation rare earth detectors with uniform, across the field of vision resolution of 2.0 mm. CT was used for attenuation correction, localization and diagnosis. Quantitative parameter used is SUV which was measured using body weight. Imaging data were processed using proprietary Scenium software before final image reconstruction. SUV values of patients were compared with normal age control with two standard deviation. Deviation below -2 was considered as low uptake and above +2 as high uptake.  

Out of 23 patients with autism 95% (22) patients had reduced uptake in one or both hippocampus while 82% (19) patients had reduced uptake in bilateral hippocampi. 82% (19) patients had low uptake in one or both amygdala while 65% (15) patients had low uptake in bilateral amygdala. Only 39% (9) patients had low uptake in one or both parahippocampal region while only 26%(6) patients showed low uptake in bilateral parahippocampal region. 65% (15) patients had low uptake in one or both mesial temporal lobes while 52% (12) patients had reduced uptake in bilateral mesial temporal lobe. 56% (13) patients had low uptake in one or both cerebellum and 47%(11) had reduced uptake in bilateral cerebellum. There was no increase in uptake in hippocampus, amygdala and mesial temporal lobes on both sides. There was increased uptake in 74% (17) patients in one or more frontal lobes whereas 61% (14) had increased uptake in bilateral frontal lobes. Only 2 patients showed low uptake in both frontal lobes.

There is significantly low uptake in majority of autistic patients in hippocampus and amygdala followed by mesial temporal lobe and cerebellum with high uptake in frontal lobes.

PET CT can prove to be potential diagnostic tool in autism. 

Chivate, R, Thakrar, P, Narang, J, Patkar, D, Kumar, S, Verma, M, PET/CT in Autism- A Diagnostic Tool.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14014693.html