PT  - JOURNAL ARTICLE
AU  - Z.I. Wang
AU  - B. Krishnan
AU  - D.W. Shattuck
AU  - R.M. Leahy
AU  - A.N.V. Moosa
AU  - E. Wyllie
AU  - R.C. Burgess
AU  - N.B. Al-Sharif
AU  - A.A. Joshi
AU  - A.V. Alexopoulos
AU  - J.C. Mosher
AU  - U. Udayasankar
ED  - ,
AU  - S.E. Jones
TI  - Automated MRI Volumetric Analysis in Patients with Rasmussen Syndrome
AID  - 10.3174/ajnr.A4914
DP  - 2016 Sep 08
TA  - American Journal of Neuroradiology
4099  - http://www.ajnr.org/content/early/2016/09/08/ajnr.A4914.short
4100  - http://www.ajnr.org/content/early/2016/09/08/ajnr.A4914.full
AB  - BACKGROUND AND PURPOSE: Rasmussen syndrome, also known as Rasmussen encephalitis, is typically associated with volume loss of the affected hemisphere of the brain. Our aim was to apply automated quantitative volumetric MR imaging analyses to patients diagnosed with Rasmussen encephalitis, to determine the predictive value of lobar volumetric measures and to assess regional atrophy differences as well as monitor disease progression by using these measures.MATERIALS AND METHODS: Nineteen patients (42 scans) with diagnosed Rasmussen encephalitis were studied. We used 2 control groups: one with 42 age- and sex-matched healthy subjects and the other with 42 epileptic patients without Rasmussen encephalitis with the same disease duration as patients with Rasmussen encephalitis. Volumetric analysis was performed on T1-weighted images by using BrainSuite. Ratios of volumes from the affected hemisphere divided by those from the unaffected hemisphere were used as input to a logistic regression classifier, which was trained to discriminate patients from controls. Using the classifier, we compared the predictive accuracy of all the volumetric measures. These ratios were used to further assess regional atrophy differences and correlate with epilepsy duration.RESULTS: Interhemispheric and frontal lobe ratios had the best prediction accuracy for separating patients with Rasmussen encephalitis from healthy controls and patient controls without Rasmussen encephalitis. The insula showed significantly more atrophy compared with all the other cortical regions. Patients with longitudinal scans showed progressive volume loss in the affected hemisphere. Atrophy of the frontal lobe and insula correlated significantly with epilepsy duration.CONCLUSIONS: Automated quantitative volumetric analysis provides accurate separation of patients with Rasmussen encephalitis from healthy controls and epileptic patients without Rasmussen encephalitis, and thus may assist the diagnosis of Rasmussen encephalitis. Volumetric analysis could also be included as part of follow-up for patients with Rasmussen encephalitis to assess disease progression.AbbreviationsHRvolinterhemispheric ratio (affected side/unaffected side)IVIGintravenous immunoglobulinRERasmussen encephalitisSVRegsurface and volume registration