gms | German Medical Science

Objective: In the recent literature several radiological investigations discussed the role of fractionated anisotropy (fA) and consistency for malignancy. There is a correlation between the fA and the consistency of meningioma tissue. Some groups showed that the fA may be a predictor for malignancy. We present our current results for the correlation between fA, consistency and malignancy. Furthermore we evaluated the impact of meningioma consistency on malignancy, early progression and grade of resection.

Method: We enrolled 71 patients into this analysis. For 45 patients the fA value was measured through a preoperative MRI with a DT sequence. The fA value was calculated on the DT Image by a radiologist. The consistency of the meningioma was defined intraoperatively by the neurosurgeon and postoperatively by the pathologist. The fA value was correlated to the consistency and malignancy. Furthermore we evaluated the correlation between consistency, early progression, malignancy and grade of resection.

Results: A total of 71 meningiomas were enrolled. 55 showed histological findings of WHO I, 13 of WHO II and 3 of WHO III meningiomas. 45 meningiomas were introduced to a DTI based measurement of the fA. The only prognostic factor found for early recurrence were the grade of resection according to Simpson's grading system (p=0.015) and WHO grading system for malignancy (p=0.007). In 45 meningiomas a fA was available with a highly significant correlation between the fA value and the consistency of meningiomas (p=0.001). But we did not find any significant correlations or tendencies between consistency and malignancy, grade of resection or early progression.

Conclusions: We confirmed in our investigations that the fA value may be able to predict the consistency of meningiomas. But there is no correlation found between the consistency or fA value and malignancy. The only prognostic factors for early progression are the well known grade of resection and malignancy. In this observation we enrolled skull base as well as parasagittal and convexity meningiomas. Further investigations should be done to evaluate the influence of the consistency on the grade of resection, recurrence and preservation of cranial nerve function, if involved.