Long-term effects of radiation therapy on white matter of the corpus callosum: a diffusion tensor imaging study in children

Abstract

Background Despite improving survival rates, children are at risk for long-term cognitive and behavioral difficulties following the diagnosis and treatment of a brain tumor. Surgery, chemotherapy and radiation therapy have all been shown to impact the developing brain, especially the white matter. Objective The purpose of this study was to determine the long-term effects of radiation therapy on white matter integrity, as measured by diffusion tensor imaging, in pediatric brain tumor patients two years after the end of radiation treatment, while controlling for surgical interventions. Materials and Methods We evaluated diffusion tensor imaging performed at two time points: a baseline three to twelve months after surgery and a follow-up approximately two years later in pediatric brain tumor patients. A region of interest analysis was performed within three regions of the corpus callosum. Diffusion tensor metrics were determined for participants (N=22) who underwent surgical tumor resection and radiation therapy and demographically matched with participants (N=22) who received surgical tumor resection only. Results Analysis revealed that at two years post treatment, the radiation treated group exhibited significantly lower fractional anisotropy and significantly higher radial diffusivity within the body of the corpus callosum compared to the group that did not receive radiation. Conclusion The findings indicate that pediatric brain tumor patients treated with radiation therapy may be at greater risk of experiencing long-term damage to the body of the corpus callosum than those treated with surgery alone.

Oral processing speed as a key mechanism in the relationship between neurological risk and adaptive functioning in survivors of pediatric brain tumors

“…Importantly, lifesaving treatments also pose neurotoxic effects. For example, radiation dose and repeated surgeries have been associated with poorer outcomes in physical abilities, personal care, participation in routine activities, and overall quality of life 19‐22 …”

Proliferation of Bilateral Nerve Fibers Following Thalamic Infarction Contributes to Neurological Function Recovery: A Diffusion Tensor Imaging (DTI) Study

“…Diffusion tensor imaging (DTI) uses water molecules as a ubiquitous marker to provide an unprecedented and quantitative capability to probe tissue microstructures noninvasively [ 28 ]. It has been extensively used to evaluate microstructural changes in the white matter of the brain in vivo [ 29 , 30 ]. Previous studies using animal models have shown that synaptic plasticity and axonal growth are associated with increases in FA in recovered brain regions after stroke [ 31 , 32 ].…”

Long-term cognitive outcome in adult survivors of an early childhood posterior fossa brain tumour

“…This may particularly be the case given the role of white matter in cortical information processing and integration [29]. Links with damage to various white matter tracts have been reported [30,31]. It has also been demonstrated recently that in addition to long-term effects of radiotherapy on cognition, functional impairments in cognition and diffuse white matter changes may be detected as soon as 3 months after treatment with wider-field, cranial-spinal radiotherapy compared to local radiotherapy [32].…”