Diffusion Tensor Tractography in Two Cases of Kernohan-Woltman Notch Phenomenon
A 25-year-old woman presented to our hospital after being assaulted. Initial Glasgow Coma Scale was 10/15. Initial CT scan revealed a large amount of acute left frontotemporoparietal SDH and frontal intracranial hemorrhage with uncal herniation to the right. An emergent craniectomy and hematoma removal was performed (). Physical examination showed left side hemiparesis: Motor grade, 2/5; Fugl-Meyer assessment, upper 8+lower 12=20/100; Manual Function Test, left 16/32. After the operation, her cognitive function coincided with a Rancho Los Amigos level of function VI. MRI was obtained 10 days after injury to find the cause of the ipsilateral motor weakness, and abnormal signal change of the right cerebral peduncle contralateral to the primary lesion was detected. The round-shaped region of decreased intensity in the right crus cerebri on T1-weighted images and high signal intensity on T2-weighted images were observed (). DTI scanning was performed 8 weeks after injury using the same protocol as stated in case 1.\nDTT did not reconstruct right CST around the midbrain due to the lower level of lesion in the T1-weighted image. Also, the CST from the cerebral cortex to the PLIC was not reconstructed. However, CST disrupted in the midbrain level was reconstructed after using different ROI method: one ROI was placed on the CST portion of the anterior lower pons and the other was placed on the CST portion of PLIC (). The FA and ADC values were obtained segmentally as in case 1 on both sides (). Decreased FA value and increased ADC value were noted on the right cerebral peduncle and anterior pons area compared to those on the left side. Four weeks after rehabilitation program, she was independent in ambulation and the motor weakness was improved: Motor grade 3/5. Her cognitive function improved to level VII with Rancho Los Amigos Scale. We re-evaluated the functional status 15 months after the onset of injury. The patient showed gradual improvement of functional abilities. She was able to grasp and release small objects and to ambulate independently: Fugl-Meyer assessment, upper 58+lower 31=89/100; Manual Function Test, left 30/32. However, we could not obtain a follow-up DTI because the patient refused the evaluation.