Individual feature maps: a patient-specific analysis tool with applications in temporal lobe epilepsy

PurposeMRI-based diagnosis of temporal lobe epilepsy (TLE) can be challenging when pathology is not visually evident due to low image contrast or small lesion size. Computer-assisted analyses are able to detect lesions common in a specific patient population, but most techniques do not address clinically relevant individual pathologies resulting from the heterogeneous etiology of the disease. We propose a novel method to supplement the radiological inspection of TLE patients ($$n=15$$n=15) providing patient-specific quantitative assessment.MethodRegions of interest are defined across the brain and volume, relaxometry, and diffusion features are extracted from them. Statistical comparisons between individual patients and a healthy control group ($$n=17$$n=17) are performed on these features, identifying and visualizing significant differences through individual feature maps. Four maps are created per patient showing differences in intensity, asymmetry, and volume.ResultsDetailed reports were generated per patient. Abnormal hippocampal intensity and volume differences were detected in all patients diagnosed with mesial temporal sclerosis (MTS). Abnormal intensities in the temporal cortex were identified in patients with no MTS. A laterality score correctly distinguished left from right TLE in 12 out of 15 patients.ConclusionThe proposed focus on subject-specific quantitative changes has the potential of improving the assessment of TLE patients using MRI techniques, possibly even redefining current imaging protocols for TLE.

[1]  S. Deoni,et al.  High‐resolution T1 mapping of the brain at 3T with driven equilibrium single pulse observation of T1 with high‐speed incorporation of RF field inhomogeneities (DESPOT1‐HIFI) , 2007, Journal of magnetic resonance imaging : JMRI.

[2]  Hamid Soltanian-Zadeh,et al.  Mesial temporal lobe epilepsy lateralization using SPHARM-based features of hippocampus and SVM , 2012, Medical Imaging.

[3]  Luis Concha,et al.  Extratemporal White Matter Abnormalities in Mesial Temporal Lobe Epilepsy Demonstrated with Diffusion Tensor Imaging , 2006, Epilepsia.

[4]  M. Miller,et al.  Correction of B0 susceptibility induced distortion in diffusion-weighted images using large-deformation diffeomorphic metric mapping. , 2008, Magnetic resonance imaging.

[5]  Alain Trouvé,et al.  Computing Large Deformation Metric Mappings via Geodesic Flows of Diffeomorphisms , 2005, International Journal of Computer Vision.

[6]  Terry M. Peters,et al.  Quantitative relaxometry and diffusion MRI for lateralization in MTS and non-MTS temporal lobe epilepsy , 2014, Epilepsy Research.

[7]  Bruce Hermann,et al.  Ipsilateral and Contralateral MRI Volumetric Abnormalities in Chronic Unilateral Temporal Lobe Epilepsy and their Clinical Correlates , 2005, Epilepsia.

[8]  P. Thompson,et al.  Quantitative analysis of structural neuroimaging of mesial temporal lobe epilepsy. , 2013, Imaging in medicine.

[9]  Catherine R. Traynor,et al.  Thalamotemporal impairment in temporal lobe epilepsy: A combined MRI analysis of structure, integrity, and connectivity , 2014, Epilepsia.

[10]  Keith R. Laws,et al.  Testing for a deficit in single-case studies: Effects of departures from normality , 2006, Neuropsychologia.

[11]  Paul H. Garthwaite,et al.  On comparing a single case with a control sample: An alternative perspective , 2009, Neuropsychologia.

[12]  Karl J. Friston,et al.  Voxel-Based Morphometry—The Methods , 2000, NeuroImage.

[13]  B. Bernhardt,et al.  Mapping thalamocortical network pathology in temporal lobe epilepsy , 2012, Neurology.

[14]  F Andermann,et al.  Analysis of shape and positioning of the hippocampal formation: an MRI study in patients with partial epilepsy and healthy controls. , 2005, Brain : a journal of neurology.

[15]  Brian A. Nosek,et al.  Power failure: why small sample size undermines the reliability of neuroscience , 2013, Nature Reviews Neuroscience.

[16]  D. C. Howell,et al.  Comparing an Individual's Test Score Against Norms Derived from Small Samples , 1998 .

[17]  Norbert Schuff,et al.  Voxel‐based T2 Relaxation Rate Measurements in Temporal Lobe Epilepsy (TLE) with and without Mesial Temporal Sclerosis , 2007, Epilepsia.

[18]  Bernd Weber,et al.  Voxel‐Based Statistical Analysis of Fractional Anisotropy and Mean Diffusivity in Patients with Unilateral Temporal Lobe Epilepsy of Unknown Cause , 2013, Journal of neuroimaging : official journal of the American Society of Neuroimaging.

[19]  B. Rutt,et al.  Rapid combined T1 and T2 mapping using gradient recalled acquisition in the steady state , 2003, Magnetic resonance in medicine.

[20]  John S. Duncan,et al.  Voxel-based diffusion tensor imaging in patients with mesial temporal lobe epilepsy and hippocampal sclerosis , 2008, NeuroImage.

[21]  Hamid Soltanian-Zadeh,et al.  FLAIR signal and texture analysis for lateralizing mesial temporal lobe epilepsy , 2010, NeuroImage.

[22]  E. Halgren,et al.  Side Matters: Diffusion Tensor Imaging Tractography in Left and Right Temporal Lobe Epilepsy , 2009, American Journal of Neuroradiology.

[23]  Luis Concha,et al.  Mesial temporal sclerosis is linked with more widespread white matter changes in temporal lobe epilepsy☆ , 2012, NeuroImage: Clinical.

[24]  A. Alexander,et al.  Diffusion tensor imaging of the brain , 2007, Neurotherapeutics.

[25]  T. Peters,et al.  High‐resolution T1 and T2 mapping of the brain in a clinically acceptable time with DESPOT1 and DESPOT2 , 2005, Magnetic resonance in medicine.

[26]  Stephen M. Smith,et al.  A global optimisation method for robust affine registration of brain images , 2001, Medical Image Anal..

[27]  Paul H. Garthwaite,et al.  Single-case research in neuropsychology: A comparison of five forms of t-test for comparing a case to controls , 2012, Cortex.

[28]  Bernd Weber,et al.  Concomitant Fractional Anisotropy and Volumetric Abnormalities in Temporal Lobe Epilepsy: Cross-Sectional Evidence for Progressive Neurologic Injury , 2012, PloS one.

[29]  Graeme D. Jackson,et al.  Composite voxel-based analysis of volume and T2 relaxometry in temporal lobe epilepsy , 2008, NeuroImage.

[30]  Donald W Gross,et al.  Diffusion tensor imaging in temporal lobe epilepsy , 2011, Epilepsia.

[31]  N. Roberts,et al.  Voxel‐based morphometry of temporal lobe epilepsy: An introduction and review of the literature , 2008, Epilepsia.

[32]  Stephen T. C. Wong,et al.  Distinguishing Left or Right Temporal Lobe Epilepsy from Controls Using Fractional Anisotropy Asymmetry Analysis , 2010, MIAR.

[33]  Brian A. Nosek,et al.  Power failure: why small sample size undermines the reliability of neuroscience , 2013, Nature Reviews Neuroscience.

[34]  M. Youdim,et al.  Iron involvement in neural damage and microgliosis in models of neurodegenerative diseases. , 2000, Cellular and molecular biology.

[35]  Gaby S Pell,et al.  Voxel-based relaxometry: a new approach for analysis of T2 relaxometry changes in epilepsy , 2004, NeuroImage.

[36]  Umberto Aguglia,et al.  TEMPORAL LOBE ABNORMALITIES ON BRAIN MRI IN HEALTHY VOLUNTEERS: A PROSPECTIVE CASE-CONTROL STUDY , 2010 .

[37]  F. Cendes,et al.  3T MRI Quantification of Hippocampal Volume and Signal in Mesial Temporal Lobe Epilepsy Improves Detection of Hippocampal Sclerosis , 2014, American Journal of Neuroradiology.

[38]  Young-Min Shon,et al.  Group‐specific regional white matter abnormality revealed in diffusion tensor imaging of medial temporal lobe epilepsy without hippocampal sclerosis , 2010, Epilepsia.

[39]  Terry M. Peters,et al.  Detection of temporal lobe epilepsy using support vector machines in multi-parametric quantitative MR imaging , 2015, Comput. Medical Imaging Graph..

[40]  S. Deoni,et al.  Transverse relaxation time (T2) mapping in the brain with off‐resonance correction using phase‐cycled steady‐state free precession imaging , 2009, Journal of magnetic resonance imaging : JMRI.

[41]  Terry M Peters,et al.  Synthetic T1-weighted brain image generation with incorporated coil intensity correction using DESPOT1. , 2006, Magnetic resonance imaging.

[42]  Eric Halgren,et al.  MRI analysis in temporal lobe epilepsy: Cortical thinning and white matter disruptions are related to side of seizure onset , 2011, Epilepsia.

[43]  J. Geweke,et al.  Interpreting the Likelihood Ratio Statistic in Factor Models When Sample Size is Small , 1980 .