Injury of Corticospinal Tract in a Patient with Subarachnoid Hemorrhage as Determined by Diffusion Tensor Tractography: A Case Report

Abstract

We report diffusion tensor tractography (DTT) of the corticospinal tract (CST) in a patient with paresis of all four limbs following subarachnoid hemorrhage (SAH) with intraventricular hemorrhage (IVH) after the rupture of an anterior communicating artery (ACoA) aneurysm rupture. The 73-year-old female was admitted to our emergency room in a semi-comatose mental state. After coil embolization-an acute SAH treatment-she was transferred to our rehabilitation department with motor weakness development, two weeks after SAH. Upon admission, she was alert but she complained of motor weakness (upper limbs: MRC 3/5, and lower limbs: MRC 1/5). Four weeks after onset, DTT showed that the bilateral CSTs failed to reach the cerebral cortex. The left CST demonstrated a wide spread of fibers within the corona radiata as well as significantly lower tract volume (TV) and higher fractional anisotropy (FA) as well as mean diffusivity (MD) compared to the controls. On the other hand, the right CST shifted to the posterior region at the corona radiata, and MD values of the right CST were significantly higher when compared to the controls. Changes in both CSTs were attributed to vasogenic edema and compression caused by untreated hydrocephalus. We demonstrate in this case, two different pathophysiological entitles, contributing to this patient's motor weakness after SAH.

Relationship between Visual Perception and Microstructural Change of the Superior Longitudinal Fasciculus in Patients with Brain Injury in the Right Hemisphere: A Preliminary Diffusion Tensor Tractography Study

“…The FA values represent the directionality at a microscopic level, at the level of the microstructure of axons, myelin, and of microtubules [ 15 , 33 , 34 ]. The TV values indicate the number of voxels within the neural tracts [ 15 ]. Therefore, decrements in the values of FA and TV indicate neural tract injury [ 19 ].…”

“…Therefore, decrements in the values of FA and TV indicate neural tract injury [ 19 ]. The MD values showed the quantitation of water diffusion, and the differences reflected the variation within the inter- and extracellular space and a decrement of neuropil [ 14 , 15 , 35 , 36 ]. Increases in the MD value have been shown to contribute to atrophy or differences in tissue density [ 36 ].…”

“…Increases in the MD value have been shown to contribute to atrophy or differences in tissue density [ 36 ]. Therefore, changes in these parameters reflect the presence of neural injury [ 15 , 35 , 37 , 38 ]. Additionally, LI indicates microstructural white matter asymmetry [ 31 ].…”

“…Diffusion tensor tractography (DTT), derived from diffusion tensor imaging (DTI), is a magnetic resonance imaging (MRI) technique employed to measure the diffusion of water molecules in neural fibers. It allows for the visualization and reconstruction of neural tracts, and may reveal injury of these tracts not detected by conventional MRI [ 4 , 6 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. Many studies have reported that microstructural fiber changes after a stroke influences cognitive functions, and the lateralization index of the arcuate fasciculus, for example, has been shown to play an important role in the prognosis of language impairment after a stroke [ 4 , 13 , 20 , 21 , 22 ].…”

Experimental and Clinical Treatment of Subarachnoid Hemorrhage after the Rupture of Saccular Intracranial Aneurysms

“…The call for papers on this topic was met with a great response by researchers and clinicians from all over the world. Among 16 basic science and clinical research submissions, our editorial team selected nine articles for publication after extensive peer review, which included three original papers [ 1 , 2 , 3 ], three reviews [ 4 , 5 , 6 ], two case reports [ 7 , 8 ] and one technical note [ 9 ]. The remaining seven papers were not included, thus yielding a 44% rejection rate.…”