🧠 MRI Myelination Assessment (Neonatal / Infant)
Mark T1/T2 MRI findings structure by structure and check them against normal myelination milestones, from preterm through preschool, using an onset (☆ some normal infants) – completion (★ all normal infants) two-stage window to flag delayed myelination by corrected or gestational age. Free, browser-based reference for radiologists, neonatologists and pediatric neurologists.
The two-stage window reduces false positives: absence before onset is normal, and delay is only flagged when signal is still absent past the age by which all normal infants show it.
MRI Myelination Assessment (Neonatal / Infant)
This is an interactive, structure-by-structure assessment. Open the dedicated tool to enter the age, choose the sequence and mark each finding.
Open interactive assessment →When to use
Use during reporting or review of preterm/neonatal/infant brain MRI to judge whether each structure's signal is appropriate for the corrected age, and to surface regions that appear delayed. This is an interactive, structure-by-structure assessment — click Open interactive assessment to enter the age, choose the sequence and mark each finding.
How it works
Each site has an onset (☆) – completion (★) window for T1 hyperintensity and T2 hypointensity. Absence before the onset age is normal; within the onset window it may be present or absent in normal infants (indeterminate); absence past the completion age is scored as delay (mild if ≤2 months over, marked if >2 months over).
Key points
- The two-stage window reduces false positives: absence before onset is normal, and delay is only flagged when signal is still absent past the age by which all normal infants show it.
- T1 signal change precedes T2 change at the same site; choose the sequence that matches the infant's age for the most informative read.
- Use corrected age (not chronological age) for preterm infants to avoid apparent (false) delay.
- PLIC and brainstem should be myelinated at term; splenium precedes genu; frontal peripheral WM and peripheral cerebellar WM mature latest (T2 up to 12–18 months) with the widest individual variation.
- An isolated structure within its onset window, or mildly delayed, is often normal variation — interpret with symmetry, developmental assessment and follow-up.
- Marked diffuse delay warrants consideration of HIE sequelae, leukodystrophy, congenital infection or metabolic disease.
References
- Jiangsu Radiology Society, Pediatric Group — Advances in Pediatric Imaging & Radiation Protection teaching materials: normal term-infant myelination timetable / T1WI·T2WI appearance-by-month star chart.
- Barkovich AJ, Kjos BO, Jackson DE, Norman D. Normal maturation of the neonatal and infant brain: MR imaging at 1.5 T. Radiology 1988.
- van der Knaap MS, Valk J. Magnetic Resonance of Myelination and Myelin Disorders, 3rd ed. Springer, 2005.
- Arthurs OJ, et al. Normal myelination on MRI: a pictorial review. Pediatr Radiol 2017.