.1. Magnetic Resonance Imaging Studies Of Parkinson's Disease (2) Preoperative Language Functional Magnetic Resonance Imaging In Neurosurgery

Objectives1. To evaluate the feasibility of characterizing iron deposition in PD using susceptibility-weighted imaging (SWI).2. To investigate the correlation of brain iron accumulation with the clinical status in patients with PD.Subjects and MethodsForty patients with PD without dementia and 26 age- and sex-matched healthy controls underwent high-resolution susceptibility-weighted magnetic resonance (MR) imaging. The phase shift values of the bilateral red nucleus (RN), substantia nigra (SN), caudate nucleus (CA), globus pallidus (GP), putamen (PU) thalamus (TH) and frontal white matter (FWM) were examined for their relationship with the clinical status.Results1. Previously published regional iron concentrations vs. we observed SWI phase shift valuesIn healthy controls, we observed a positive correlation (r = 0.903, P = 0.005) between SWI phase shift values and previously published regional iron concentrations. (Hallgren and Sourander, 1958) This validates our application of SWI as a viable MRI method for the noninvasive estimation of regional brain iron content.2. Hemispheric differences in the healthy controlsThere were no significant hemispheric differences with regards to phase shift values in the healthy human brain.3. The most affected vs. the least affected brain side in PD The most affected body side of symptoms is assessed with Unified Parkinson's Disease Rating Scale (UPDRS) motor score. The contralateral brain side is referred as"the most affected brain side"; the ipsilateral brain side referred as"the least affected brain side". The paired-sample t test showed a difference between the controls and the patients in the SN (P = 0.000), but not in the other regions studied.4. The most affected brain side in PD vs. the healthy controlsIndependent t-tests showed that there were no significant phase shift value differences in other regions of interest (ROIs) except for the SN (P = 0.001).5. The least affect brain side in PD vs. the healthy controlsIndependent t-tests showed that there were no significant phase shift value differences in the regions of interest (ROIs).6. Correlations between the phase shift values in the SN of the most affected and least affected brain side in PD and its durationNo relationship was found between the phase shift values and the disease duration in the SN of the clinically most affected side or the least side (the most affected side, r = 0.142, P = 0.381; the least affected side, r= 0.287, P = 0.073).7. Correlations between the phase shift values in the SN of the most affected and least affected brain side in PD and the UPDRS motor scorePearson's correlation analysis showed that there was a positive correlation between the phase shift values in the SN of the clinically most affected and least affected brain side in PD and the UPDRS motor score (the most affected side, r = 0.412, P = 0.008; the least affected side, r= 0.361, P = 0.022).8. Difference in the phase shift values of the SN between earlier-onset and later-onset PDThere were 15 cases of earlier-onset PD (the mean phase shift value in the SN = 0.14401±0.06205) and 25 cases of later-onset PD (the mean phase shift value in the SN = 0.16430±0.04776). No significant difference was detected between earlier- and later-onset PD (P = 0.253). ConclusionsBrain iron concentration can be evaluated by SWI. Also, the brain iron concentration in the SN correlated with UPDRS motor score, indicating that iron concentration can function as an in vivo biomarker to objectively evaluate the status of PD. ObjectivesTo explore the Regional Homogeneity alterations in patients with Parkinson's disease and to investigate the correlation between these changes and clinical index. Subjects and MethodsThirty-four patients with PD without dementia and 34 healthy controls underwent resting-state functional magnetic resonance (MR) imaging. After the data preprocessing, the Regional Homogeneity alterations were calculated with the DPARSF and REST software package.Results1. The ReHo maps of the healthy controls and the patients with Parkinson's disease( one-sample t test)The default mode network including the posterior cingulate cortex (PCC)/precuneus, medial prefrontal cortex (MPFC), and bilateral inferior parietal lobe (IPL) exhibited significant higher ReHo than other brain areas, which indicates that the ReHo method could reflect the spontaneous neuronal activity of the default mode network.2. Comparison of the ReHos between the healthy controls and the patients with Parkinson's disease (two-sample t test)Compared with the healthy controls, the patients with PD at off state showed significant ReHo increases in the bilateral precuneus, left occipital middle gyrus, left calcarine cortex, right precentral gyrus and right lingual gyrus and significant ReHo decrease in the left angular gyrus, left olfactory cortex, right frontal middle gyrus, right fusiform area, right calcarine, right cerebellum, right temporal middle gyrus and left temporal inferior gyrus, right parahippcampal gyrus and left supplemental motor area.3. Correlations between ReHo and UPDRS in patients with PD Correlation analysis of ReHo at each voxel in the whole brain against the UPDRS in the patients with PD at off state revealed significantly positive correlation in the right fusiform area,left rectus gurus, right parietal inferior lobe, right parahippocampla gyrus, right frontal superior orbital gyrus, right supramarginal gyrus and right frontal inferior triangular area and revealed significant negative correlation in the right cerebelun 8 and 9 area.4. Correlations between ReHo and disease duration in patients with PDCorrelation analysis of ReHo at each voxel in the whole brain against the disease duration in the patients with PD at off state revealed significantly positive correlation in the left precentral gyrus, right temporal middle gyrus, left cerebellum crus, left frontal middle gyrus, left cerebellum posterior lobe, right precuneus and right cungulum posterior part; and revealed significant negative correlation in the left brainstem and right inferior parietal lobe.ConclusionsThe current study demonstrates that neural activity in the resting state is changed in patients with PD. This change is related to the severity and the duration of the disease, which provided new perspective and tool to explore the pathophysiology of the Parkinson's disease. Objective1. To evaluate the sensitivity and accuracy of preoperative language cortex functional MRI localization.2. To characterize the alteration of language function under the circumstances of intracranial lesion around the language area.3. To determine the safety distance between the core activation of language functional region and the lesion during the resection.4. To assess the clinical value of functional neuronavigation during the resection of language area around lesions.MethodsThirty-one patients who had lesions in or around the language cortex were recruited in the study. As the help of neuronavigation we integrated the conventional MRI and fMRI images together and localized the position of the language cortex and lesion. In the course of operation the patients were awaked, the technique of direct cortical stimulation was performed to assess the sensitivity and accuracy of preoperative language cortex functional MRI localization. We compared the results of preoperative and postoperative fMRI in patients, and compared the language status before and after operation.Results1. The results of each fMRI paradigm in patients: The outcome of each fMRI paradigm was rated by'very good','fair'and'unsuccessful'. Forty-seven language tasks were implemented in 31 patients, 20 tasks were rated'very good', 20 tasks rated were'fair', 4 tasks were rated'unsuccessful'. In total 23 Broca's area activations, 5 tasks were rated'very good', 13 tasks were rated'fair'. In total 24 Wernicke's area activations, 15 tasks were rated'very good', 7 tasks were rated'fair'. 2. The consistence of fMRI activation area and direct cortical stimulation: The distance between the fMRI core activation and direct cortical stimulation was rated as overlapping (<1cm distance), adjacent (<2cm distance), discrepancy (>2cm distance). We performed 26 cases measurement, 12 cases were rated overlapping, 14 cases were rated adjacent, no cases showed discrepancy.3. The outcome of the fMRI neuronavigation assisted operation: Total lesion resection was achieved in 12 cases, subtotal resection in 8 cases, partial resection in 11 cases. Postoperatively the neurologic functions were improved in 7 cases, unchanged in 19 cases, temporary worsen in 5 cases, no persisting deficits.4. Correlation between the distance of resection border-to-language cortex and outcome: Resection border more than 10mm from the functional areas is safe. All the patients the neurologic functions were improved or unchanged. Three cases caught the temporary worsen, the distances were less than 10mm, and resumed in a week.Conclusions1. The influence of the language cortex around lesion on the outcome of the fMRI is limited; the successes rate of preoperative language cortex localization fMRI is high either on 1.5T or 3.0T MRI scanner; the outcome of preoperative language cortex localization fMRI is consistent well with that of intra-operative electrical stimulation, which could effectively decrease the incidence rate of language function damage during the resection the lesion around the language cortex.2. Under the circumstances of fMRI neuronavigation, if the distance between the core activation and the lesion is more than 10mm, it is unnecessary to implement intra-operative awaked electrical stimulation; if the distance between the core activation and the lesion is between 5mm and 10mm, intra-operative awaked electrical stimulation should been applied; if the distance between the core activation and the lesion is less than 5mm, intra-operative awaked electrical stimulation should been implemented very cautiously. But temporary language function damage is often unavoidable at this moment.