Magnetic Resonance Imaging (MRI) uses magnetic fields and radio waves to generate detailed, non-invasive images of the brain. The technology does not involve radiation, making it a safe diagnostic tool for infants by providing a clear view of brain structure and development. While the process can be stressful for parents, understanding its purpose can be reassuring, as it is designed to be as safe and comfortable for the infant as possible.
Why a Newborn Brain MRI is Performed
A physician may order a brain MRI for a newborn for several reasons, often related to events during birth or signs observed afterward. Complications during labor and delivery, such as a lack of oxygen or blood flow (hypoxia-ischemia), can prompt the need for an MRI to assess for brain injury. Difficult deliveries or other trauma during the birthing process are also indicators that a scan may be necessary.
Certain clinical signs in a newborn can also lead to an MRI referral. The presence of seizures, a sign of abnormal electrical activity in the brain, is a primary reason for imaging. Abnormal muscle tone, either being too floppy (hypotonia) or too stiff (hypertonia), can suggest underlying neurological issues. Other physical signs that may warrant a detailed brain scan include feeding difficulties, an unusually large or small head size, or a bulging soft spot on the head (fontanelle).
Premature infants are frequently monitored with brain imaging due to their higher risk for certain brain injuries. Their developing brains have fragile blood vessels, making them more susceptible to bleeding or white matter damage. An MRI provides a detailed view of the brain’s structure for the early detection and management of these potential issues.
The Newborn MRI Procedure
The MRI procedure for a newborn is carefully managed to ensure the baby’s safety and comfort while obtaining high-quality images. A common method is the “feed and swaddle” technique. The baby is fed shortly before the scan and then wrapped snugly in a blanket, which helps them fall into a natural sleep. This approach often eliminates the need for sedation, as a sleeping baby will remain still enough for the scan.
In cases where an infant cannot settle, sedation may be used. This is administered and monitored by a specialized medical team to ensure the baby’s vital signs remain stable throughout the procedure. The goal is to keep the baby safe and comfortable while allowing the MRI technician to capture clear, motion-free images. Parents are informed about the sedation protocol beforehand, including any instructions on feeding or fasting.
During the scan, the swaddled infant is placed in a protective cradle that slides into the MRI machine. The machine is a large, tunnel-shaped device that can be loud, so the baby is fitted with appropriately sized earmuffs for hearing protection. A neonatal nurse often monitors the baby from an adjacent room, and the infant’s heart rate and oxygen levels are continuously tracked. The entire procedure lasts between 30 and 60 minutes.
Types of Brain Damage Identified by MRI
An MRI can reveal several specific types of brain abnormalities or injuries in a newborn, providing information that is not always visible with other imaging techniques like ultrasound. One of the most common conditions identified is Hypoxic-Ischemic Encephalopathy (HIE), which results from a deprivation of oxygen and blood flow to the brain around the time of birth. On an MRI, HIE can appear as abnormally bright areas on certain imaging sequences, and the pattern of injury can help determine the timing and severity of the oxygen deprivation.
Periventricular leukomalacia (PVL) is another condition diagnosed with MRI, especially in premature infants. PVL involves damage to the brain’s white matter, the tissue responsible for transmitting signals between different brain regions. This damage can appear as bright spots on T2-weighted images or as cysts in more severe cases. Because white matter controls motor function, PVL is often associated with movement disorders.
Bleeding within the brain, known as a hemorrhage, is also visible on an MRI. Intraventricular hemorrhage (IVH) is bleeding into the brain’s fluid-filled ventricles and is a risk for premature babies. An MRI can pinpoint the location and extent of the bleed, which can range from small bleeds that resolve on their own to large hemorrhages that cause pressure and damage. Neonatal stroke, which can be either ischemic (caused by a blocked blood vessel) or hemorrhagic, is also identifiable.
An MRI can also detect issues with the brain’s structure. These congenital malformations are problems in how the brain formed during fetal development. For example, a condition called agenesis of the corpus callosum, where the band of nerve fibers connecting the two hemispheres of the brain fails to develop, can be identified. The scan can also reveal signs of infection, such as meningitis or encephalitis, by showing inflammation in the brain tissues.
Interpreting the MRI Results
After the MRI scan is completed, the images are analyzed by a pediatric radiologist, a physician with specialized training in interpreting medical images of children. The radiologist writes a detailed report that describes the findings, noting the appearance of different brain structures and identifying any abnormalities. This report provides a technical description of what was observed on the various MRI sequences.
The medical team, including the neonatologist or pediatric neurologist, then discusses this report with the parents. The MRI is one component of a larger diagnostic picture. The findings from the scan are correlated with the baby’s clinical condition, the events of the pregnancy and delivery, and the results of other tests to form a comprehensive understanding of the infant’s health.
The information from the MRI directly influences the baby’s treatment and care plan. A diagnosis of HIE may support the use of therapeutic hypothermia (cooling therapy), a treatment that can reduce the extent of brain damage if started soon after birth. If the MRI reveals a structural issue or a specific type of injury like PVL, it helps the team anticipate future needs, such as physical, occupational, or developmental therapies.
The MRI findings also provide information regarding the baby’s long-term outlook. The location and extent of any identified brain damage can help predict the likelihood of future developmental challenges. This allows the medical team to establish a follow-up care plan, ensuring the infant receives ongoing monitoring and early intervention services to support their development.