The Characteristic Of FMRI In Language Cortex Of Normal Chinese And Clinical Application Of FMRI Neuronavigation In Or Around Language Cortex

Preservation of function during surgery for lesions in or around language cortex is a challenge for neurosurgeons,especially in neurologically intact patients.The precise location of language cortex is the best way to solve this problem. It has been shown that functional magnetic resonance imaging(fMRI) with blood oxygen level-dependent contrast is capable of evaluating cortical activity noninvasively and in a task-specific manner.There are two things we should do before the clinical application of fMRI.The first thing is to get the best language task which can activate the Broca's area and Wernicke's area. The second thing is to make clear the sensitivity and correlation of language cortex in fMRI.Objectives:The aim of this study is to get the best language tasks which can activate the Broca's area and Wernicke's area and to assess the sensitivity and correlation of language cortex in fMRI .Methods:In the first part of this research,we analyzed the characteristic of fMRI in language cortex of normal chinese in different language tasks.Then,we got the the best language tasks which can activate the Broca's area and Wernicke's area respectively.In the second part of this research,we choosed the patients who had lesions in or around language cortex. As the help of neuronavigation we infused the MRI and fMRI together and located the position of language cortex and lesion.In the course of operation the patients were awake, the technique of direct cortical stimulation was used to assess the sensitivity and correlation of language cortex in fMRI. In the last,we compared the results of preoperative and postoperative fMRI in patients, and compared the language status.Results:1.The characteristic of Broca's area activation in nomal chinese at different language tasks: No head motion and no Broca's area activation in reading(silently) group; 9 cases of Broca's area activiation were observed in reciting group,the curves of time-signal change were steadily, head motion slightly;7 cases of Broca's area activiation were observed in picture naming group and 8 cases in reading group, intensive visual cortex activiation were observed in the same time, head motion severely.2. The characteristic of Wernicke's area activation in nomal chinese at different language tasks: Right temporal lobe activiation was observed in music group. Activiation located mainly in left temporal lobe(Wernicke ) in word comprehension group and paragraph comprehension group in all cases, the signals were more clear and steady in paragraph comprehension group.3.The heat-dependent materials can fasten the head of patients properly,it is a good method to decrease head motion and improve the image of fMRI.4.The results of each fMRI paradigm in patients: The success of each fMRI paradigm was rated by'very good','fair'and'unsuccessful'.18 patients finished 29 language tasks, 12 tasks were'very good',15 tasks were'fair',2 tasks were'unsuccessful'.In total 15 Broca's area activation,3 tasks were'very good',12 tasks were'fair'.In total 13 Wernicke's area activation, 8 tasks were'very good',4 tasks were'fair'.5.The correlation of fMRI activation area and direct cortical stimulation: The distance between the fMRI peak and direct cortical stimulation was rated as overlapping (<1cm diatance),neighbouring (<2cm diatance),contradictory (>2cm diatance).we finished 16 cases measurement,9 cases were overlapping,7 cases were neighbouring,no cases showed contradictory.6.The characteristic of activation areas and fiber tracts by the lesions:In some patients,we observed the activation areas decreased,dislocation or dispersed, the activation areas increased and focused after operation.We also observed the phenomenon of dislocation,disrupted and destroyed in fiber tracts.7.The outcome of the fMRI neuronavigation assisted operation:Total lesion resection was achieved in 7 cases,subtotal resection in 5 cases,partial resection in 6 cases.Postoperatively the neurologic functions were improved in 4 cases,unchanged in 11 cases,temporary worsen in 3 cases,no persisting deficits.8.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 tempory worsen,the distances were less than 10mm,and resumed in a week.Conclusions:1. Reciting task in Chinese can activate the Broca's area steadily in fMRI.2. Paragraph comprehension task in Chinese can activate the Wernicke area steadily in fMRI.3. fMRI in language cortex is sensitive and precise.4. The safe distance between resection border and language cortex is 10mm.5. With the help of the neuronavigation, the combination of fMRI with DTI is helpful for decreasing the side effect injury in the operations in or around language cortex.