Amygdala structure and function and its associations with social-emotional outcomes in a low-risk preterm sample.

Amygdala atypical volume development and functional connectivity (FC) at small gestational ages (GA) have been found across childhood. This adult-oriented study assesses whether altered amygdala structure and function is present following low-risk preterm birth. T1-weighted and resting-state functional MRI images of 33 low-risk preterm (30-36 weeks' GA) and 29 full-term (37-42 weeks' GA) young adults of both sexes, aged between 20 and 32 years old, were analyzed using FreeSurfer (v6.0.0) and Coon Toolbox (v21.a). The social-emotional assessment included Happé's Strange Stories Test, the Moral Judgment Test, Delay-Discounting Test, Adult Self Report, and Emotion Regulation Questionnaire. No differences were found in social-emotional outcomes or amygdala volumes between the groups. Low-risk preterm young adults showed increased FC between the left amygdala, right amygdala and medial frontal cortex (MedFC) (F = 9.89, p-FWE = 0.009) at cluster level compared to their full-term peers. However, significant results at connection level were not observed between left and right amygdala. Lastly, increased FC at cluster level between the right amygdala and MedFC, and left amygdala and MedFC, was related to better social-emotional outcomes only in low-risk preterm young adults (F = 6.60, p-FWE = 0.036) at cluster level. At connection level, in contrast, only right amygdala-MedFC increased FC was significantly associated with better social-emotional outcomes. This study reveals that low-risk prematurity does not have an effect on social-emotional outcomes or structural amygdala volumes during young adulthood. However, individuals who were considered to be at a lower risk of exhibiting neurodevelopmental alterations following preterm birth demonstrated increased FC between the left and right amygdala and MedFC.

[Low grade astroblastoma: pathological and magnetic resonance findings]. / Astroblastoma de baixo grau: Achados patológicos e da ressonância magnética.

INTRODUCTION: The astroblastoma is an uncommon type of glial tumour. It accounts for less than 1% of all tumours of the central nervous system. It originates in the tanicytes, ependymal cells present in the embryo and usually seen in adolescents and young adults. Radiologically it presents as a well delimited, heterogeneous tumour with a solid component which takes up contrast and is cystic, giving the same signal as cerebrospinal fluid (CSF). The pathological characteristics are of the formation of radial astroblastic pseudorosettes with perivascular hyalinization. CASE REPORT: An 18 year old woman presented with a 15 month history of motor deficit of her right limbs with occasional left frontal headache and horizontal diplopia on looking towards the left. On examination there was minimal claudication of the right limbs and bilateral papilloedema. Magnetic resonance showed a very well circumscribed left prefrontal neoplasm of heterogeneous aspect, with areas of solid and cystic appearance in the different sequences. The area of cystic appearance did not show the CSF signal in all sequences of the pulse. The tumour was totally excised. On histological study there were radial astroblastic pseudorosettes with perivascular hyalinization, with two mitoses per 10 fields of great magnification and the final diagnosis was of low grade astroblastoma. The apparently cystic portion was composed of friable gelatinous tissue. Fifteen months after her operation the patient is still asymptomatic. CONCLUSION: We report the radiological and pathological findings of a low grade astroblastoma.