Automated MRI Volumetric Analysis in Patients with Rasmussen Syndrome.
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.



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.



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.



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.
From the Epilepsy Center (Z.I.W., B.K., A.N.V.M., E.W., R.C.B., A.V.A., J.C.M.) wangi2@ccf.org.
Z I
0000-0002-3829-5217
ZI
Wang
From the Epilepsy Center (Z.I.W., B.K., A.N.V.M., E.W., R.C.B., A.V.A., J.C.M.).
B
0000-0002-1897-3359
B
Krishnan
Ahmanson-Lovelace Brain Mapping Center (D.W.S., N.B.A.-S.), Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California.
D W
0000-0002-8424-8905
DW
Shattuck
Signal and Image Processing Institute (A.A.J., R.M.L.), University of Southern California, Los Angeles, California.
R M
0000-0002-7278-5471
RM
Leahy
From the Epilepsy Center (Z.I.W., B.K., A.N.V.M., E.W., R.C.B., A.V.A., J.C.M.).
A N V
0000-0002-3123-5713
AN
Moosa
From the Epilepsy Center (Z.I.W., B.K., A.N.V.M., E.W., R.C.B., A.V.A., J.C.M.).
E
0000-0002-0864-6645
E
Wyllie
From the Epilepsy Center (Z.I.W., B.K., A.N.V.M., E.W., R.C.B., A.V.A., J.C.M.).
R C
0000-0003-2297-2022
RC
Burgess
Ahmanson-Lovelace Brain Mapping Center (D.W.S., N.B.A.-S.), Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California.
N B
0000-0003-3941-1416
NB
Al-Sharif
Signal and Image Processing Institute (A.A.J., R.M.L.), University of Southern California, Los Angeles, California.
A A
0000-0002-9582-3848
AA
Joshi
From the Epilepsy Center (Z.I.W., B.K., A.N.V.M., E.W., R.C.B., A.V.A., J.C.M.).
A V
0000-0003-0214-3286
AV
Alexopoulos
From the Epilepsy Center (Z.I.W., B.K., A.N.V.M., E.W., R.C.B., A.V.A., J.C.M.).
J C
0000-0002-3221-229X
JC
Mosher
Department of Radiology (U.U.), University of Arizona College of Medicine, Tucson, Arizona.
U
0000-0001-5605-9851
U
Udayasankar
Imaging Institute (S.E.J.), Cleveland Clinic, Cleveland, Ohio.
S E
0000-0001-6511-9078
SE
Jones
D000328:Adult; D001284:Atrophy / Q000473:pathology; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology; D004660:Encephalitis / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male