Diffusion Tensor MR Imaging of Cerebral Gliomas: Evaluating Fractional Anisotropy Characteristics

• Published in: American journal of neuroradiology : AJNR Vol. 32; no. 2; pp. 374 - 381
• Main Authors: WHITE, M. L, ZHANG, Y, YU, F, KAZMI, S. A. Jaffar
• Format: Journal Article
• Language: English
• Published: Oak Brook, IL American Society of Neuroradiology 01-02-2011
• Subjects: Adolescent; Adult; Adult and adolescent clinical studies; Aged, 80 and over; Anisotropy; Biological and medical sciences; Brain; Brain Neoplasms - pathology; Child; Child, Preschool; Diffusion Tensor Imaging; Female; Glioma - pathology; Humans; Infant; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Middle Aged; Miscellaneous; Mood disorders; Nervous system; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Retrospective Studies; Severity of Illness Index; Young Adult; Nervous system diseases; Glioma; Radiodiagnosis; Anisotropy; Central nervous system disease; Central nervous system; Tumor; Encephalon; Diffusion tensor imaging
• ISSN: 0195-6108; 1936-959X
• DOI: 10.3174/ajnr.a2267

FA correlation to glioma tumor grade has been mixed if not disappointing. There are several potential underlying fundamental issues that have contributed to these results. In an attempt to overcome these past shortfalls, we evaluated characteristics of FA of the solid tissue components of gliomas, including whether high-grade gliomas have a greater variation of FA than low-grade gliomas.
Thirty-four patients with gliomas (9 grade II, 8 grade III, and 17 grade IV) underwent diffusion tensor imaging at 3T. Mean FA, maximum FA, and minimum FA values were measured within the solid tissue components of the tumors. The variations of FA were evaluated by determining the range of FA values and the maximum SDs of FA. The variations of FA values among different tumor grades were compared statistically. We also correlated FA variations with minimum FA and maximum FA.
The maximum FA, FA range, and maximum SD for grade II tumors were significantly lower than those for grade III and IV tumors (P < .0001 ∼ P = .0164). A very good correlation of maximum FA to FA range (r = 0.931) and maximum SD (r = 0.889) was observed.
The FA range and maximum SD appear useful for differentiating low- and high-grade gliomas. This analysis added value to the findings on conventional MR imaging. In addition, focal maximum FA is a key factor contributing to the larger FA variation within high-grade gliomas.