A 67-year-old man was admitted to our hospital with a history of weakened left limbs and muscle twitching. On physical examination the muscle strength of the left upper limb was grade 2 and grade 4 on the lower limb. T2-weighted MRI revealed the lesion involving the right centrum ovale and part of the precentral gyrus. The FA value of the affected white matter was slightly lower (0.28) compared with the contralateral side (0.40). DTI-based fiber-tracking displayed a right CST passing through the lesion without interruption (fig. ). The patient refused surgery, therefore no histopathological diagnosis was made. However, an increased choline concentration (maximum choline/creatine and choline/N-acetylaspartate ratios of 3.04 and 4.51, respectively) was detected in the lesion with MRS study, which was highly suggestive of tumor.
A 24-year-old male presented with right frontal-parietal glioblastoma. The FA and color-coded maps showed decreased FA value and destruction of white matter fibers. 3D tractography was initiated from the brain stem for CST. The right CST passing through the periphery of the lesion was compressed and deviated anteromedially by the lesion. The AF was compressed and deviated superiorly by the lesion, and was close to the tumor margin (Figure ).