Brain MRI findings in paediatric genetic disorders associated with white matter abnormalities.
Jaakko H Oikarainen, Oula A Knuutinen, Salla M Kangas and 7 others
PMID 39080972WHAT IT FOUND
Brain MRI patterns in 83 children with genetic white matter disorders show that corpus callosum thinning is common across many disease types.
Specific combinations of white matter changes, calcifications, or restricted diffusion can help distinguish between rare diagnoses.
Key findings
01Abnormalities of the corpus callosum, particularly thinning or hypoplasia, were found in 29 patients (35%) and occurred in 25 different diseases across all subtypes of genetic white matter disorders.
02Specific imaging signs can suggest particular diagnoses: restricted diffusion was seen only in patients with mitochondrial disorders like Leigh syndrome and MELAS, while calcifications were found in patients with CRMCC1 and one with MELAS.
03Not all patients with these genetic disorders had abnormal MRIs; 11 patients (13%) showed no notable white matter or brain abnormalities, possibly due to young age at imaging or disease progression.
STILL TO COME
How it was doneWhat they found
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The study included only 83 patients across 52 different genetic disorders, meaning many diagnoses were represented by only one or two cases, which makes it difficult to establish reliable imaging patterns for individual rare diseases. MRI protocols and scanner field strengths varied significantly over the 30-year period (1990-2019), which may affect the consistency of image interpretation. Patients without available MRI data were excluded, potentially introducing selection bias. The cohort is from Northern Finland, a population with unique genetic characteristics (founder effects), so the prevalence of specific disorders and their imaging patterns may not generalize to other populations. Some patients had normal MRIs despite having a genetic diagnosis, which complicates the use of MRI as a standalone screening tool in early disease stages.
Declared interests
The authors declared no conflicts of interest. The study was funded by the Research Council of Finland.
The easy way to misread this
Do not assume that a normal brain MRI rules out a genetic white matter disorder. In this cohort, 11 patients (13%) had no notable white matter abnormalities despite having confirmed genetic diagnoses, often because they were imaged at a very young age before changes became visible.