Combining advanced MRI and EEG techniques better explains long-term motor outcome after very preterm birth.

BACKGROUND: Preterm born children are at high risk for adverse motor neurodevelopment. The aim of this study was to establish the relationship between motor outcome and advanced magnetic resonance imaging (MRI) and electroencephalography (EEG) measures. METHODS: In a prospective cohort study of 64 very preterm born children, the motor outcome was assessed at 9.83 (SD 0.70) years. Volumetric MRI, diffusion tensor imaging (DTI), and EEG were acquired at 10.85 (SD 0.49) years. We investigated associations between motor outcome and brain volumes (white matter, deep gray matter, cerebellum, and ventricles), white matter integrity (fractional anisotropy and mean, axial and radial diffusivity), and brain activity (upper alpha (A2) functional connectivity and relative A2 power). The independence of associations with motor outcome was investigated with a final model. For each technique, the measure with the strongest association was selected to avoid multicollinearity. RESULTS: Ventricular volume, radial diffusivity, mean diffusivity, relative A2 power, and A2 functional connectivity were significantly correlated to motor outcome. The final model showed that ventricular volume and relative A2 power were independently associated with motor outcome (B = -9.42 × 10-5, p = 0.027 and B = 28.9, p = 0.007, respectively). CONCLUSIONS: This study suggests that a lasting interplay exists between brain structure and function that might underlie motor outcome at school age. IMPACT: This is the first study that investigates the relationships between motor outcome and brain volumes, DTI, and brain function in preterm born children at school age. Ventricular volume and relative upper alpha power on EEG have an independent relation with motor outcome in preterm born children at school age. This suggests that there is a lasting interplay between structure and function that underlies adverse motor outcome.

Cerebellar injury in preterm infants: incidence and findings on US and MR images.

PURPOSE: To investigate the incidence and characteristics of cerebellar injury in a cohort of very preterm infants by using the mastoid fontanelle (MF) and posterior fontanelle (PF) approach in addition to routine cranial ultrasonography (US) through the anterior fontanelle (AF), with magnetic resonance (MR) imaging as the reference standard. MATERIALS AND METHODS: The institutional review board approved this prospective study and informed consent was obtained. A cohort of 77 preterm infants (< 32 weeks) was examined with serial cranial US throughout the neonatal period by using the AF, PF, and MF views. MR imaging was performed around term-equivalent age in 59 of 77 infants. Sensitivity, specificity, positive predictive value, and negative predictive value of routine cranial US and cranial US with additional views were calculated. RESULTS: At cranial US performed through the MF, seven (9%) of 77 infants were identified to have posterior fossa hemorrhage. In only two of seven infants, the lesions were seen on routine AF views. The PF approach did not increase the detection rate of posterior fossa hemorrhage. MR images confirmed cranial US findings in all cases. MR images showed punctate hemorrhage in the cerebellum in six infants with normal cranial US findings. Among the 59 infants examined with both cranial US and MR imaging, cerebellar injury was diagnosed in 11 (19%). CONCLUSION: Cerebellar injury is a frequent finding in very preterm infants. Cranial US through the MF can demonstrate injury missed by using the routine AF approach. Punctate hemorrhagic lesions may remain undetected even when the MF approach is used; the prognostic implications of these smaller lesions need further attention.