Structural Changes in the Cortico-Ponto-Cerebellar Axis at Birth are Associated with Abnormal Neurological Outcomes...

Area of Science:

• Neuroscience
• Developmental Biology
• Radiology

Background:

• White matter lesions in hypoxic-ischemic encephalopathy (HIE) are a primary cause of neurological deficits in preterm infants.
• The cortico-ponto-cerebellar axis is crucial for motor control and cognitive functions, and its development can be affected by perinatal brain injury.

Purpose of the Study:

• To analyze volumetric and tractographic alterations in the cortico-ponto-cerebellar pathways in infants with and without HIE.
• To assess prospective transsynaptic changes in the cerebellum and their correlation with neurological outcomes.

Main Methods:

• Brain MRI was performed at term-equivalent age and 2 years in term infants (control), preterm infants without HIE (normotypic), and preterm infants with HIE.
• Volumetric analysis of brain structures and fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of specific white matter tracts were measured.
• Neurological assessments included the Amiel-Tison scale and the Hempel test.

Main Results:

• Reduced volumes of cerebellum, brainstem, and specific compartments were observed in normotypic and HIE groups at term-equivalent age.
• At 2 years, the HIE group showed significantly reduced volumes, decreased FA, and increased ADC in corticopontine and corticospinal pathways.
• Brainstem, cerebellum, pons, and corticopontine volumes, along with corticospinal FA at term-equivalent age, negatively correlated with 2-year neurological scores.

Conclusions:

• The cortico-ponto-cerebellar pathways are vulnerable to injury in HIE, exhibiting persistent structural changes.
• Structural differences between normotypic and HIE groups at 2 years suggest altered developmental structural plasticity.
• Cerebellum and pons volumes may serve as potential prognostic indicators for neurological outcomes in HIE survivors.