Purpose: The aim of this study was to investigate the efficacy of DWI
findings in predicting the histological degree of meningiomas preoperatively and the relationship between ADC value and the most important
prognosis determinant index, Ki-67 proliferation index..
Methods: Between March 2013 – July 2020, 54 patients who underwent
cranial MRI including diffusion, who had a pathological outcome as
meningioma, and whose Ki-67 index was examined, were analyzed retrospectively. The threshold ADC value for low and high grade tumor
separation was calculated by ROC analysis. The correlation of Ki-67
proliferation index and ADC values was investigated.
Results: The mean ADC value in low-grade meningiomas was found
as 976,674 ± 105,443 x 10-6 mm2 / sec, and the average ADC value
in high-grade meningiomas was 813,727 ± 102,998 x 10-6 mm2 /
sec and this difference was found statistically significant (p <
0,001). The threshold ADC value was found to be 882.50 x 10-6
mm2 / s ( p <0.05), sensitivity at this value was calculated as 83.7%
and specificity as 81.8%. The Ki-67 proliferation index was 5.77 ±
2.438 in low-grade meningiomas and 16 ± 8.955 in high-grade tumors, and these differences were statistically significant (p <0.001).
There was a significant negative correlation (correlation) between
Ki-67 index and mean ADC values ( p = 0.008) Conclusion: DWI could be used in the differentiated between low and
high grade meningiomas.Ki-67 proliferation index and average ADC
values can be used together in terms of meningioma grade.