Meta-analysis Of Diffusion Tensor Imaging FA Values And ADC Values Applied In The Glioma Grading And Infiltration

Objective：To evaluate the usefulness of diffusion tensor imaging FA values andADC values applied in the gliomas grading and infiltration.Methods：With no blind method and publish status restrictions in the computerretrieval, two reviewers independently searched "(apparent diffusion coefficient) ORADC OR (fractional anisotropy) OR FA AND Glioma [MeSH Terms] AND humans[MeSH Terms]"in the Pubmed database, EMBASE databases,CBM, CNKI,Wanfang database and CQVIP database.The relevant Neurosurgery magazines andNeuroimaging magazines, the academic proceedings on the field of Neurosurgery andthe relevant reviews references were inspected by manual retrieval. We use thescoring criteria recommended by NICE to assess the quality of the includedresearches. It was Meta-analysis that used in the glioma grading and tumorinfiltrating.Result: Finally,15pieces of studies about diffusion tensor imaging FA valuesand ADC values applied in the gliomas grading and infiltration were included. Firstheterogeneity analysis was used for the included researches. A fixed effect approachwas adopted unless there was evidence of significant unexplained heterogeneity, inwhich case a random effects approach was used. Then combine the results andanalyze them so that we could get the followings:⑴FAvalues of LGG in tumor centre were lower than HGG (WMD=-0.02,95%CI[-0.03,-0.01]), the results were statistically significant; ADC values of LGG in tumorcentre were higher than HGG (WMD=0.15,95%CI [0.02,0.28]), the results werestatistically significant.⑵FA values in LGG tumor centre were lower than that in LGG peritumoraledema (WMD=-0.13,95%CI[-0.19,-0.07]), the results were statistically significant;ADC values in LGG tumor centre were higher than that in LGG peritumoral edema (WMD=0.21,95%CI[0.05,0.37]), the results were statistically significant. FA valuesin LGG peritumoral edema were lower than that in LGG NAWA (WMD=-0.08,95%CI[-0.14,-0.03]), the results were statistically significant; ADC value inLGG peritumoral edema were higher than that in LGG NAWA (WMD=0.38,95%CI[0.14,0.61]), the results were statistically significant. FA values in LGG tumorcentre were lower than LGG NAWA(WMD=-0.25,95%CI[-0.29,-0.21]), the resultswere statistically significant; ADC values in LGG tumor centre were higher thanLGG NAWA (WMD=0.57,95%CI [0.24,0.89]), the results were statisticallysignificant.⑶FA values in HGG tumor centre were lower than that in HGG peritumoraledema (WMD=-0.07,95%CI[-0.12,-0.02]), the results were statistically significant;ADC values in HGG tumor centre and in HGG peritumoral edema were nodiffererce(WMD=-0.02,95%CI[-0.12,0.08])， the results were not statisticallysignificant. FA values in HGG peritumoral edema were lower than that in HGGNAWA (WMD=-0.20,95%CI[-0.27,-0.13]), the results were statistically significant; ADCvalues in HGG peritumoral edema were higher than that in HGG NAWA(WMD=0.52,95%CI[0.39,0.66]), the results were statistically significant. FA values inHGG tumor centre were lower than HGG NAWA (WMD=-0.27,95%CI[-0.34,-0.19]), theresults were statistically significant; ADC values in HGG tumor centre were higher thanHGG NAWA (WMD=0.47,95%CI[0.42,0.52]), the results were statistically significant.Conclusion:⑴FA values and ADC values could be helpful in judging the degree of theglioma.⑵FA values could be helpful in determining the extent of tumor infiltration inLGG and HGG,play a very valuable role in making surgical strategy.ADC valuescould behelpful in determining the extent of tumor infiltration in LGG,but there wasno statistical difference for the determination of tumor infiltration in HGG.⑶Due to the low quality of the studies, the potential presence of publication biasand language bias, it is still necessary to carry out a series of high quality case series for a more comprehensive evaluation.