Kim Annink

43 The pattern of Purkinje cell injury in neonates with HIE due to the absence of a control group and only little variability in the severity of hypoxic-ischemia in this cohort. Lastly, several neonates were treated with therapeutic hypothermia before withdrawal of care to prevent further brain injury. In this study, hypothermia treated neonates were not separately investigated from non-hypothermia treated neonates, since the latter was just a minor group (n=5). The severity of cerebellar injury could potentially differ between infants who were treated with hypothermia and those who were not. Additional research is essential to better understand the causes and consequences of ulegyria in the vermis. It must be determined whether ulegyria injury is restricted to the vermis or if this phenomenon is also present in the cerebellar hemispheres. Also, the influence of the pattern of PC injury on neurocognitive outcome should be investigated. Supratentorial ulegyria seems to be associated with epilepsy (41), but the effect of ulefolia on outcome is unknown. In addition, it would be interesting to further quantify pathophysiology of immune responsive cells, oligodendrocytes and all neuronal cell types and establish a potential link to cerebellar ulegyria. Another potential avenue of clinical research would be to investigate subcortical white matter injury in the cerebellum, since subcortical white matter atrophy is an essential hallmark of supratentorial ulegyria. CONCLUSIONS In conclusion, we demonstrated that PCs of term neonates with HIE are injured. HIE infants have fewer PCs at the bases of the cerebellar folia and lobules compared to the crown. In addition, PCs at the bases seem to be more vulnerable to hypoxia. This pattern of PC injury is comparable to supratentorial ulegyria. FUNDING The PhD position of the first author Kim V. Annink is funded by the Horizon 2020 research and innovation Program of the European Union (call H2020-PHC-2015-two- stage, grant 667224, ALBINO). DISCLOSURES The authors have no conflict of interest to declare. 2