Advanced

AJNR - American Journal of Neuroradiology

Published ahead of print on November 30, 2007
doi: 10.3174/ajnr.A0810

This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: ajnr.A0810v1 29/2/366    most recent Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Hourani, R. Articles by Horská, A. Search for Related Content PubMed PubMed Citation Articles by Hourani, R. Articles by Horská, A.

American Journal of Neuroradiology 29:366-372, February 2008
© 2008 American Society of Neuroradiology

BRAIN

Can Proton MR Spectroscopic and Perfusion Imaging Differentiate Between Neoplastic and Nonneoplastic Brain Lesions in Adults?

R. Hourani^a,d, L.J. Brant^c, T. Rizk^e, J.D. Weingart^b, P.B. Barker^a,f and A. Horská^a

^a Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Hospital, Baltimore, Md
^b Department of Neurological Surgery, Johns Hopkins Hospital, Baltimore, Md
^c National Institutes of Health/National Institute on Aging, Gerontology Research Center, Baltimore, Md
^d Department of Radiology, American University of Beirut Medical Center, Beirut, Lebanon
^e Department of Neurosurgery, Hotel Dieu Hospital, Beirut, Lebanon
^f FM Kirby Research Center, Kennedy Krieger Institute, Baltimore, Md

Please address correspondence to Alena Horská, PhD, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, 217 Traylor Bldg, 720 Rutland Ave, Baltimore, MD 21205. E-mail: ahorska{at}jhmi.edu

BACKGROUND AND PURPOSE: Noninvasive diagnosis of brain lesions is important for the correct choice of treatment. Our aims were to investigate whether 1) proton MR spectroscopic imaging (¹H-MRSI) can aid in differentiating between tumors and nonneoplastic brain lesions, and 2) perfusion MR imaging can improve the classification.

MATERIALS AND METHODS: We retrospectively examined 69 adults with untreated primary brain lesions (brain tumors, n = 36; benign lesions, n = 10; stroke, n = 4; demyelination, n = 10; and stable lesions not confirmed on pathologic examination, n = 9). MR imaging and ¹H-MRSI were performed at 1.5T before biopsy or treatment. Concentrations of N-acetylaspartate (NAA), creatine (Cr), and choline (Cho) in the lesion were expressed as metabolite ratios and were normalized to the contralateral hemisphere. Dynamic susceptibility contrast-enhanced perfusion MR imaging was performed in a subset of patients (n = 32); relative cerebral blood volume (rCBV) was evaluated. Discriminant function analysis was used to identify variables that can predict inclusion in the neoplastic or nonneoplastic lesion groups. Receiver operator characteristic (ROC) analysis was used to compare the discriminatory capability of ¹H-MRSI and perfusion MR imaging.

RESULTS: The discriminant function analysis correctly classified 84.2% of original grouped cases (P < .0001), on the basis of NAA/Cho, Cho_norm, NAA_norm, and NAA/Cr ratios. MRSI and perfusion MR imaging had similar discriminatory capabilities in differentiating tumors from nonneoplastic lesions. With cutoff points of NAA/Cho 0.61 and rCBV 1.50 (corresponding to diagnosis of the tumors), a sensitivity of 72.2% and specificity of 91.7% in differentiating tumors from nonneoplastic lesions were achieved.

CONCLUSION: These results suggest a promising role for ¹H-MRSI and perfusion MR imaging in the distinction between brain tumors and nonneoplastic lesions in adults.