title: Is there a role for apparent diffusion coefficients in the differential diagnosis of brain tumors?
abstract: We determined the potential benefits of apparent diffusion coefficient (ADC) values of enhancing-nonenhancing solid portions, cystic-necrotic areas and surrounding edema in the differential diagnosis of brain tumors. Eighty-eight patients with brain tumors: 16 low-grade gliomas, 21 high-grade gliomas, 26 metastases and 25 meningiomas were imaged prospectively in a 1.5 Tesla magnetic resonance (MR) unit. Routine MR imaging and echo-planar diffusion-weighted imaging (DWI) with b values of 0 and 1000 mm(2)/s were performed. ADC values were obtained in different tumor parts and peritumoral edema. The ADCs of contrast-enhancing tumor regions were higher in high-grade gliomas than meningiomas (p<0.05). No significant differences were found in ADCs of contrast-enhancing regions comparing other tumor groups (p≥0.05). The ADCs in non-enhancing tumor regions did not differ between low-grade and high-grade gliomas (p≥0.05). The ADCs in cystic-necrotic regions of tumors and surrounding edema were not significantly different comparing all tumor groups (p≥0.05). There were no significant differences between ADCs of contrast-enhancing and non-enhancing regions of high-grade and low-grade gliomas (p≥0.05). No significant differences were found in ADCs of contrast-enhancing and non-enhancing areas of tumors comparing to surrounding edema (p≥0.05). ADC was not found to be useful in distinguishing different tumor types and its value in the diagnosis of brain tumors is limited due to considerable overlaps.
authors.affiliation: Department of Radiology, Gazi University School of Medicine; Ankara, Turkey - niltokgoz@yahoo.com - nil.tokgoz@gazi.edu.tr.
authors.forename: N
authors.initials: N
authors.lastname: Tokgoz
authors.forename: H
authors.initials: H
authors.lastname: Celik
authors.forename: S
authors.initials: S
authors.lastname: Gultekin
authors.forename: N K
authors.initials: NK
authors.lastname: Voyvoda
authors.forename: A Y
authors.initials: AY
authors.lastname: Oner
authors.forename: E T
authors.initials: ET
authors.lastname: Tali