Diffusion of the Corpus Callosum in Young Infants

Response to Letter to the Editor: Diffusion of the Corpus Callosum in Young Infants

We have read the paper by Tan and Lim with great interest.[1] Their findings that restricted diffusion within the splenium of the corpus callosum may be a normal finding in infants less than 4 months of age when imaged on a 3T system are in contrast with our previous observations in infants with perinatal asphyxia.[2]

Since their findings are so much different from ours, it is very important to provide clinical details about the infants in their study, in particular the infants who were apparently “healthy.” The reasons for these infants to be scanned and clinical findings should be made clearer than in the supplementary table provided. Furthermore, apparent diffusion coefficient (ADC) measurements of the corpus callosum should be given, since diffusion weighted images are very much dependent of the settings of the MR system. The importance of measuring ADC values has been demonstrated more than a decade ago in this journal.[3]

Until then, we are still convinced that diffusion restriction in the posterior part of the corpus callosum with ADC values below 0.969 × 10⁻³ mm²/s is a pathological finding in newborn infants.

• References

• 1 Tan AP, Lim YT. “Restricted Diffusion” within the splenium of the corpus callosum: a potential pitfall in young infants on 3T imaging and marker of normal myelin maturation. Neuropediatrics 2019; 50 (03) 146-151
• 2 Alderliesten T, de Vries LS, Khalil Y. , et al. Therapeutic hypothermia modifies perinatal asphyxia-induced changes of the corpus callosum and outcome in neonates. PLoS One 2015; 10 (04) e0123230
• 3 Vermeulen RJ, Fetter WP, Hendrikx L, Van Schie PE, van der Knaap MS, Barkhof F. Diffusion-weighted MRI in severe neonatal hypoxic ischaemia: the white cerebrum. Neuropediatrics 2003; 34 (02) 72-76