Diffusion Tensor Imaging Predicts Long-Term Motor Functional Outcome in Patients with Acute Supratentorial Intracranial Hemorrhage

Abstract

Background/Aim: It remains unclear how wallerian degeneration of the pyramidal tract (PT) in the acute phase of supratentorial intracranial hemorrhage (ICH) correlates with the long-term functional outcome. The aim of this study was to quantify and predict the long-term neuromotor outcome using diffusion tensor imaging (DTI) during the early stages of ICH. Methods: Twenty-seven patients with a hemiparetic ICH were prospectively studied using DTI either within 3 days or at 2 weeks after onset. A region-of-interest-based analysis was performed for fractional anisotropy (FA) of the PT in the cerebral peduncle. The degree of paresis was assessed upon admission and at 6 months using paresis grading (PG), and the functional outcome was evaluated using the modified Rankin Scale (mRS). The activities of daily living were evaluated using the Functional Independence Measure (FIM). Results: The FA values within 3 days and after 2 weeks of ICH onset were significantly decreased at the affected side (p = 0.001, reduced by 11%; p < 0.001, reduced by 14%, respectively), but the mean diffusivity at the same time points remained unchanged (p = 0.05 and p = 0.136, respectively). The ratio of the FA (rFA) at the affected side to that of the unaffected side within 3 days was negatively correlated with the PG (p < 0.001, r = –0.642), positively correlated with the FIM scores (p = 0.004, r = 0.532), and negatively correlated with the mRS scores at the end of follow-up (median = 17 months) (p = 0.010, r = –0.490). The rFA at 2 weeks was positively correlated with the FIM (p < 0.001, r = 0.661) and negatively correlated with mRS scores and PG at the end of follow-up (p < 0.001, r = –0.653; p < 0.001, r = –0.700). For both patients with good and poor outcomes based on the PG, the area under the receiver operating characteristic (ROC) curve for rFA at 2 weeks was greater than the area under the ROC for rFA within 3 days, and the cutoff point for the rFA at 2 weeks was set at 0.875 (sensitivity 76%, specificity 89%). Conclusions: This study demonstrated that the use of DTI during the early stages of ICH may predict motor outcomes at 6 months after ICH. Moreover, as compared to use of DTI within 3 days of ICH onset, the application of DTI at 2 weeks after ICH could more accurately predict the motor outcomes and daily living activities of patients.

Motor outcome of deep intracerebral haemorrhage in diffusion tensor imaging: comparison of data from different locations along the corticospinal tract

“…The timing of the MRI being performed and clinical outcome evaluation are comparable with those of previously published reports, but we were able to recruit more cases than previous studies. 9,10,16 In addition, this is the first report to evaluate the relationship between the FA ratio in four different areas along the CST and motor outcomes after ICH, and the results may imply the value of microstructural change over the CST. However, further investigations are necessary to clarify the fibre change in an injured CST after ICH.…”

“…[13][14][15] Most previous studies have used only the cerebral peduncle as the ROI for FA and ADC measurements to predict motor outcomes. 9,10,16 Our study is unique in that we assessed four sites along the CST, to measure DTI indices including the corona radiata, perihaematomal oedema area, cerebral peduncle and pons. Different from previous studies, this showed that injured CST could change during the motor recovery stage among patients with ICH.…”

“…5 Recent studies using DTI and DTT have shown that reduced FA at cerebral peduncle noted 2-18 days after the putaminal or thalamic haemorrhage could predict poor short-term and long-term motor outcome. [6][7][8][9] The cerebral peduncle is distal to putamen or thalamus and reduced FA at this site is supposed to be attributed to Wallerian degeneration (WD). 10 However, in ischaemic stroke DTI study, both anterograde (WD) and retrograde degeneration occurred and were associated with poor recovery after stroke.…”

The role of advanced neuroimaging in intracerebral hemorrhage

“…A similar study by Wang et al 48 showed a comparable relationship with fractional anisotropy and independence of hematoma size, but also found that there may be differing diagnostic value when DTI is performed in the acute (3 days postictus) and subacute (2 weeks postictus) periods in hemiparetic patients. When DTI was performed in the subacute period, it was found to be more predictive of motor and functional outcome.…”

Neuroimaging in Intracerebral Hemorrhage

“…A signiicant inding being that fractional anisotropy ratio did not correlate to size of the bleed but did correlate with recovery [17], which could serve as an important tool for the prediction of recovery post ICH. The predictive value of these studies has shown to be higher when carried out subacutely (2 weeks) rather than acutely (3 days) after the bleed which may be accounted for by the resolution of acute injury and inlammation and onset of repair and compensation [18]. Functional MRI (fMRI) is being evaluated as a means to evaluate the extent of injury and functional deicit post ICH based on functional connectivity rather than just a structural basis, with fMRI possibly evaluating the activity between physical and functional connections.…”