Resting-state Functional MRI Study Of Visual Dysfunction In Patients With Occipitalia Tumor

ObjectiveTo locate the visual center networks of normal subjects andpreoperative patients with occipitalia tumor using resting-state functionalmagnetic resonance imaging (RS-fMRI) and independent componentanalysis(ICA), and to evaluate the value of using RS-fMRI and ICA in thetreatment plan and prognosis assessment of occipitalia lesion.Material and MethodsNineteen normal subjects (normal control group) who matched thepatient group in age, sex and handedness, and8patients with occipitaliatumor underwent RS-fMRI scanning and vision inspection before operation.All visual center networks in Brodmann17and Brodmann18wereanalyzed using ICA. The visual center networks appearances of the normalsubjects were viewed by two neuroradiologists. Then, the integrity anddistribution of the visual center networks of the patients were analyzedwithout knowing the clinical ocular symptoms, and were compared with the results of clinical visual field exam.ResultsThe visual center networks in Brodmann17and18areas in normalcontrol group were of integrity in bilateral visual cortex. In patients group,the strength and range of connection of visual center networks inBrodmann17and18were reduced in different degree comparing withnormal control group and the healthy side, the visual center function areashowed displacement in5cases, the integrity of the visual center networkswere impaired in6cases, the visual function connection in adjacent brainregions showed increasing in6cases, the visual center networks around thetumor demonstrated increase in4cases. The integrity of the visual centernetworks of the2patients with visual field defect was damaged and thevisual function connection in adjacent brain regions showed increasing butshowed no functional compensation surrounding the tumors. The integrityof the visual center networks were remained in2of the6patients withnormal visual field, and the integrity of visual center networks of the other4patients were damaged, while the visual function connection in adjacentbrain regions showed increasing and the visual center networkssurrounding the tumors demonstrated compensation.ConclusionRS-fMRI scan could show the distribution of the visual center networks of the normal subjects, and demonstrate the integrity of the visualcenter networks of the patients with occipitalia tumor, which has a goodconsistency with visual field exam, and is more objective and has betterpatient compliance. The patients with occipitalia tumor may have thedisplaced visual centers, damaged integrity of the visual center networks orcompensatory function area. Therefore, RS-fMRI can locate the visualcenter networks of the patient with occipitalia tumor, and help projectingthe operation or radiotherapy planning of the tumor and evaluate theprognosis for the visual function.