Objective: To investigate the hodotopical organization of neural pathway of Chinese in posterior inferior frontal gyrus. Forprovide the basis for the individual protectionoflanguage functionin the operation of the language functional area.
Methods: Twenty volunteers underwentlanguage mapping using repetitive navigated transcranial magnetic stimulation(nTMS)to identify the essential language sites in posterior inferior frontal gyrus.Then, DTI tractography was used to reconstruct language-relevant fiber tracts within posterior inferior frontal lobe. Finally, the relationships between essential language sites and language-relevant fiber tracts were analyzed.
Results: (1)Eighteen subjects hadlanguage sites which induce repeatable language errors in posterior inferior frontal gyrus. The total number of essential language sites was 39.46% of essential language sites located in ventral precentralgyrus, 41% in parsopercularis and 13% in parstriangularis. (2)Long segment of arcuate fasciculus had the probability of 100%to project into ventral precentralgyrus. Anterior segment of arcuate fasciculus had the probability of 100%to project into ventral precentralgyrus. Inferior frontal occipital fasciculus had the probability of 94% to project into parstriangularis. Uncinate fasciculus had the probability of 67% to project into parstriangularis. Aslantfiber had the probability of 100% to project into parsopercularis.(3)When the essential language site located in ventral precentralgyrus, it had the probability of 82% to correlate with long segment of arcuate fasciculus. When the essential language site located in parsopercularis, it had the probability of 79%to correlate with aslant fiber. When the essential language site located in parstriangularis, it had the probability of 60% to correlate with inferior frontal occipital fasciculus.
Conclusion: Essential language sites within distinct locations were conducted through different fasciculus, which enlightensour neurosurgeons thatin order to achieve both maximal lesions resection and language function protection, we shouldprotectboththe essential language cortices and language relevant subcortical connection according to each individual's hodotopical organization.