The CO-Occurrence of MRI Findings and Autism Spectrum Disorders:What Is the Importance of Pineal Cyst???

Background: Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder, with persistent impairment in reciprocal social communication and social interaction, and restricted, repetitive patterns of behaviour, interests or activities.There are different findings on Magnetic Resonance Imaging(MRI) and their high prevalence may be an important tool in clinical assessment as is suggested in many studies. Pineal cysts, arachnoid cysts, choroid plexus cysts, enlarged perivascular spaces, cavum septum pellucidum, asymmetrical ventricles are some of the MRI incidental findings discovered in children with ASD.

Objectives: Evaluate the simultaneous occurrence between magnetic resonance imaging findings, namely pineal cysts which shows a high prevalence in this group, and children diagnosed with autism spectrum disorders.

Methods: Retrospective case-control study carried out on 161 children: 93 cases diagnosed with autism spectrum disorder (38 with level 1 severity and 55 with level 2 severity) were compared with 68 controls (non-autistic patients). All participants had done a magnetic resonance image and were patients of the paediatric psychiatry appointments.

Results: This study shows that the prevalence of pineal cysts is higher in autistic children comparing with non-autistic children (84.6% vs 15.4%, p=0.041). If the level of severity of the autism is discriminated into level 1 and 2, there is also a significant difference between the groups (15.4% vs 84.6% vs 0.0% in non-autistic, level 1 and level 2 ASD, respectively, p<0.001). The latter association was analysed calculating the odds of the presence of pineal cyst and having level 1 autism which was increased but with a wide variability (OR, 95%CI 13.75, [2.38 – 79.38]).

Conclusions: There is a possible association between pineal cysts and autism spectrum disorders as shown in this study. This association is stronger in the children diagnosed with level 1 autism, since it is the group with the highest prevalence of pineal cysts (11.8%). It would be interesting to further explore the factors underlying this correlation by extending the study to a larger sample.