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Updated: Aug 8, 2026
Diffusion Tensor Magnetic Resonance Imaging in the Analysis of Neurodegenerative Diseases
Published on: July 28, 2013
Reversible impairment of auditory callosal pathway in 5-fluorouracil-induced leukoencephalopathy: parallel changes in
Chisato Fujimoto1, Ken Ito, Shinichi Iwasaki
1Department of Otolaryngology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
Objective:
To report the course of functional and imaging recovery of the auditory callosal pathway in a patient with 5-fluorouracil-induced leukoencephalopathy.
Design:
Case study.
Setting:
University hospital.
Patient:
A 58-year-old man with hypopharyngeal cancer who developed 5-fluorouracil-induced leukoencephalopathy.
Main Outcome Measures:
Imaging (magnetic resonance imaging) and functional (dichotic listening test) evaluation on the auditory callosal pathway.
Results:
The patient underwent systemic chemotherapy with pirarubicin, cisplatin, and 5-fluorouracil. On the last day of the regimen, the patient suddenly became restless and convulsive. On diffusion-weighted magnetic resonance images, the signal intensity at the splenium of the corpus callosum was very high. Fluid-attenuated inversion recovery images showed no abnormal findings at this time. Intravenous methylprednisolone sodium succinate and glycerin 10% was started immediately. On the ninth day after onset, the patient was free of neurologic symptoms. Although pure-tone audiograms and speech discrimination scores were normal, dichotic listening tests revealed significant left ear suppression, indicating severe injury of the auditory callosal pathway. On fluid-attenuated inversion recovery images, the signal intensity at the splenium was high, whereas the posterior trunk was normal. At 6 weeks after onset, dichotic listening test results returned to normal and hyperintensity at the splenium was much less marked on fluid-attenuated inversion recovery images.
Conclusion:
By using both functional and imaging modalities, this case study demonstrated, for the first time in a reversible manner, that the auditory callosal pathway runs through the most posterior part of the corpus callosum including the splenium. Diffusion-weighted magnetic resonance imaging was considered useful for early diagnosis of 5-fluorouracil-induced leukoencephalopathy.
