• Imaging
• Neonatology
• Neurodevelopment
• Neurodisability

MRI is a neuroimaging technique which is increasingly being used in extremely preterm infants cared for on a level 3 neonatal intensive care unit. The technique was initially introduced in the 1980s in newborn infants with severe brain injury and was considered to be very useful for the prediction of especially motor outcome. Many centres have started to perform MRI routinely at discharge or term equivalent age (TEA) and have been able to show that subtle white matter abnormalities are better and more reliably depicted with MRI than cranial ultrasound (cUS). A landmark paper by Woodward et al1 of 167 infants born before 30  weeks’ gestation concluded that abnormal findings—in particular moderate-to-severe white matter injury (WMI)—on brain MRI at TEA are significantly better at predicting adverse neurodevelopmental outcome at 2 years of age than abnormal findings on cUS. In more recent years, the MRI technique has become more sophisticated, with new sequences providing additional information. Furthermore, sequential MRI provides insight into growth and development of the brain and neuronal networks of the extremely preterm infant, using 3D-volumetric imaging, diffusion tensor imaging and functional MRI.2

MRI is considerably more expensive than cUS, necessitates the transport of infants to the scanner, often requires sedation of the patient and cannot be repeated easily. To obtain high-quality preterm MRI, age-appropriate sequences with thin slices must be used. Without sedation, there is a risk of obtaining images that display movement artefacts, making interpretation more difficult and being inferior to good sequential cUS. A single MRI at TEA will not identify a minor haemorrhage or smaller cystic lesions that may have resolved between birth and TEA (a period sometimes exceeding 3 months).

Whether every extremely preterm infant should have at least one MRI and when is the best time to perform this MRI are questions which …