Title: Evaluation of Intracranial Ring Lesions by Diffusion-Weighted Imaging and in Vivo Proton Magnetic Resonance Spectroscopy
Authors: Varun Garg, Gidugu Venkata Ramdas, Gavinder Singh Bindra, Amit Mittal, Samita Singal, Rajnish Kumar Chaudhary, Rikki Singal
DOI: https://dx.doi.org/10.18535/jmscr/v4i11.69
Abstract
AIMS & OBJECTIVES: To assess the combined role of diffusion weighted imaging and spectroscopy in differentiating ring enhancing intracranial cystic lesions.
MATERIALS AND METHIODS: The study was conducted from Oct 2011 to Sep 2013. Thirty (30) patients having ring enhancing intracranial cystic lesions were included in the study. 1.5 tesla MRI ACHEIVA (Phillips) with routine MRI sequences with diffusion weighted imaging (DWI) and ADC mapping followed by ADC value in the center of lesion was used. Proton Magnetic resonance spectroscopy was performed on these patients followed by T1W contrast. The radiological diagnosis was correlated with histopathological examination in 12 patients and the remaining were evaluated clinical parameters and blood tests by the clinicians.
RESULTS: Infective lesions were characterized by decreased Ch/NAA and decreased/ near normal Ch/Cr ratio as compared to ring enhancing cystic neoplastic lesions. Elevated lactate and lipid peaks were found to be characteristic for Tuberculomas. Cystic neoplastic lesions could be differentiated from infective lesions. Cerebral abscesses differed on the basis of elevated lactate and amino acid peaks. Brain abscesses showed high signal intensity in DWI and reduced ADC in the centre of lesion as compared to cystic neoplastic lesions.
CONCLUSIONS: The combined role of MRI with MRS and Difusion weighted imaging is found to be useful in accurate evaluation and differentiation of intra cranial cystic ring enhancing lesions. Reduced ADC value with diffusion restriction is highly suggestive of brain abscess while in absence of restriction; magnetic resonance spectroscopy is useful in distinguishing abscess from other infective lesions and cystic neoplasms.
KEYWORDS: ring enhancing cystic neoplastic lesions, brain abscess, diffusion weighted imaging, magnetic resonance spectroscopy.
References
1. Mishra AM, Gupta RK, Jaggi RS , Reddy JS, Jha DK , Husain N, et al. Role of Diffusion-Weighted Imaging and In Vivo Proton Magnetic Resonance Spectroscopy in the Differential Diagnosis of Ring-Enhancing Intracranial Cystic Mass Lesions. J Comput Assist Tomogr 2004;28:540-7.
2. Sener RN. Longstanding tectal tumors: proton MR spectroscopy and diffusion MRI findings. Comput Med Imaging Graph2002; 26 :25 –31[Medline]
3. Sinha S, Bastin ME, Whittle IR, Wardlaw JM. Diffusion tensor MR imaging of high-grade cerebral gliomas. AJNR Am J Neuroradiol2002; 23 :520 –527.
4. D. Pal, A. Bhattacharyya ,M. Husain et al. In Vivo Proton MR Spectroscopy Evaluation of Pyogenic Brain Abscesses: A Report of 194 Cases. AJNR Am J Neuroradiol. 2010; 31: 360–66.
5. Nail Bulakbasi, Murat Kocaoglu, Cem Tayfun et al. Combination of Single-Voxel Proton MR Spectroscopy and Apparent Diffusion Coefficient Calculation in the Evaluation of Common Brain Tumors. AJNR Am J Neuroradiol. 2003; 23: 225–233.
6. G. Luthraa, A. Parihara, K. Natha et al. Comparative Evaluation of Fungal, Tubercular, and Pyogenic Brain Abscesses with Conventional and Diffusion MR Imaging and Proton MR Spectroscopy. American Journal of Neuroradiology. 2007 28: 1332-1338.
7. Eun Ja Lee, David Mikulis, Dae Seob Choi, et al. Diagnostic Value of Peritumoral Minimum Apparent Diffusion Coefficient for Differentiation of Glioblastoma Multiforme From Solitary Metastatic Lesions. American Journal of Roentgenology. 2011;196: 71-76.
8. Ping H. Lai, Jih T. Ho, Wei L. Chen et al. Brain Abscess and Necrotic Brain Tumor: Discrimination with Proton MR Spectroscopy and Diffusion-Weighted Imaging. AJNR Am. J. Neuroradiol. 2002; 23:1369 - 1377.
9. Prakash Shetty, Aliasgar Moiyadi, Gouri Pantvaidya. Cystic metastasis versus brain abscess: Role of MR imaging in accurate diagnosis and implications on treatment. 2010; 6(3): 356-358.