Clinical Application Of Multi-Voxel MRS In Astrocytomas And Correlation With Ki-67,MVD

Purpose1.To evaluate the clinical value of MV-MRS in preoperated astrocyto mas.2.To explore relationship of MV-MRS with immunohistochemistry Ki-67, MVD in astrocytomas. Materials and Methods41 cases with astrocytomas were examined with MV-MRS and routine MR , and Ki-67 , MVD were examined in 28 cases, all cases were histologically proved by biopsy or operation. There were no any therapy before operating in all cases.Pathologic diagnosis were made by pathologist,all cases were divided into high grade group and low grade group.FSE T1-weighted,T2-weighted, FLAIR and FSE T1WI contrast were acquired in 1.5T MRI with eight-way junction head coil. MRS images were acquired with 3D-CSI sequence in four-way junction head coil .Stereotaxis from Axial, coronal, sagittal and the Pre-set zone of saturation were used.Shim, liquid and fat suppression were automatic completed,Raw data were transmited to workstation for past processing,The areas under the peak of various metabolite in spectra were measured,and were analyzed various metabolite of astrocytoma in high-grade and low-grade group.Ki-67 antigen labelling index and MVD counted number of pathologic specimen of the tumors were determined.The Correlation among metabolite of Multi- voxel MRS and relationship of MV-MRS with Ki-67, MVD were analyzed. Results 1. MR spectroscopy of low-grade astrocytomas has demonstrated different levels of increasing in Cho peak, and the peaks of NAA were decreased in the different levels.Cho peak increased significantly in high-grade astrocytomas, and NAA peak significantly decreased. Lac appeared in 21 cases of astrocytomas, and 11 cases high-grade astrocytomas appeared Lip peak, Lac peak were found Only in 5 patients in low-grade group.The difference in Cho /Cr, NAA/Cr, Cho / NAA rate of the two groups was significant statistically.2. Ki-67 labeling index and MVD counted number increased with histological grade malignancy of astrocytomas. Positive rate of Ki-67 antigen presentation in low-grade group was 11.726±3.375, and the positive rate in high-grade group was 23.467±4.525.The count of MVD in low-grade group was 27.529±5.536, and that in high-grade group was 44.409±12.941.There were statistical differences between the two groups.3. They could reflected biologic feature of astrocytomas in various ways that Cho /Cr,NAA /Cr ,Cho/NAA , positive rate of Ki-67 antigen and count of MVD .Allof them show regulation variety along with the malignant dissimilarity of the tumor cells.Positive linear correlation was found obviously between Cho /Cre, NAA / Cr , Cho/NAA with positive rate of Ki-67 antigen. and Lac / Cr correlated well with count of MVD. The correlation coefficiencies were 0.640,-0.573,0.694 and 0.586. The correlation between Cho/NAA with Ki-67 index was better than Cho/Cr, NAA/Cr with Ki-67 index. Conclusion1. MV-MRS is valuable to provide important information in differential diagnosis of the grade of astrocytomas, preoperatively lining out the boundary of tumor and working out rational treatment plan.2. Ki-67 and MVD is effective complement for routine pathologyical examination in the diagnosis the grade of astrocytomas.They might reflect biological feature such as tumor cell prolifelation and microvascular growth.3. There are close correlations among Cho, NAA, Lac and Ki-67, MVD. Positive linear correlation is observed among Cho /Cr, NAA /Cr, Cho/NAA with Ki-67 antigen. Lac / Cr with count of MVD also has positive linear correlation.4. MV H~1-MRS combined with immunohistochemistry examination could provide more information to work out treatment plan of astrocytomas.