Background

In addition to clinical studies of epilepsy conducted in our MEG lab (Memorial Hermann Hospital, Houston), our group is conducting an ongoing research project aimed at assessing the relative efficacy of MEG (as compared to EEG and invasive electrophysiology) in identifying epileptogenic zones.

This project was supported by NIH funds and results of our research efforts are summarized in several peer-reviewed journal publications, book chapters, and many abstracts and conference presentations (List of recent publications).

The findings reported fall into these categories:

1. The relative efficacy of MEG in identifying the epileptogenic zone.

1.1   MEG versus Non-Invasive vEEG (Pataraia et al., 2004).

1.2   MEG versus Invasive VEEG (Papanicolaou et al., 2005).

1.3   Studies on slow-waves and ictal activity (Ishabashi et al., 2002).

2. The clinical validity of MEG-derived maps of sensorimotor and linguistic function in presurgical mapping.

2.1   Presurgical functional mapping with MEG for the assessment of hemispheric
   dominance (Papanicolaou et al., 2004).

2.2   Evidence for functional reorganization of the brain (Pataraia et al., 2004b).

2.3   Functional mapping with MEG: Expressive language (Castillo et al., 2001).

2.4   Mapping of somatosensory and motor functions (Castillo et al., 2004).

Peer-review Publications

Breier, J.I., Simos, P.G., Wheless, J.W., Constantinou, J.E.C., & Papanicolaou, A.C. Language dominance in children determined by magnetic source imaging and the Intracarotid Amobarbital Procedure:  A Comparison. Journal of Child Neurology, 16(2): 124-130, 2001.

Billingsley, R.L., Simos, P.G., & Papanicolaou, A.C.  Reliability and validity of functional neuroimaging techniques for identifying language-critical areas in children and adults. Developmental Neuropsychology, 26(2):541-563, 2004.

Billingsley, R.L., Simos, P.G., Castillo, E.M., Maestu, F., Sarkari, S., Breier, J.I., Papanicolaou, A.C. Functional Brain Imaging of Language: Criteria for scientific merit and supporting data from magnetic source imaging. Journal of Neurolinguistics, 16(4-5):255-275, July-September 2003.

Billingsley, R.L., Simos, P.G., Castillo, E.M., Sarkari, S., Breier, J.I., Pataraia, E., Papanicolaou, A.C.  Spatio-temporal cortical dynamics of phonemic and semantic fluency. Journal of Clinical & Experimental Neuropsychology, 26(8):1031-43, 2004.

Breier, J.I., Castillo, E.M., Simos, P.G., Billingsley-Marshall, R.L., Pataraia, E., Sarkari, S., Wheless, J.W., Papanicolaou, A.C. Atypical language representation in patients with chronic seizure disorder and achievement deficits using magnetoencephalography. Epilepsia, 46(4):540-8, 2005.

Breier, J.I., Simos, P.G., Zouridakis, G., & Papanicolaou, A.C.  Lateralization of Activity Associated with Language Function Using Magnetoencephalography: A Reliability Study.  Journal of Clinical Neurophysiology, 17(4):503-510, 2000.

Breier, J.I.; Simos, P.G.; Zouridakis, G.; Wheless, J.W.; Wilmore, L.J.; Constantinou, J.C.; Papanicolaou, A.C. A magnetoencephalography study of cortical plasticity. Neurocase, 5(4): 277-284, 1999.

Breier, J.I.; Simos, P.G.; Zouridakis, G.; Wheless, J.W.; Wilmore, L.J.; Constantinou, J.C.; Maggio, W.W.; Papanicolaou, A.C. Language dominance determined by magnetic source imaging: A comparison with the Wada Procedure. Neurology, 53: 938-945, 1999.

Castillo, E.M., Simos, P.G., Davis, R.N., Breier, J.I., Fitzgerald, M.E., & Papanicolaou, A.C. Levels of word processing and incidental memory:  Dissociable mechanisms in the temporal lobe. Neuroreport, 12: 3561-3566, 2001.   

Castillo, E.M., Simos, P.G., Davis, R.N., Breier, J.I., Fitzgerald, M.E., & Papanicolaou, A.C.  Temporal dynamics of medial temporal lobe activation during encoding and recognition.  Spanish Review of Neuropsychology, 5, 2:99-120. 2003.

Castillo, E.M., Simos, P.G., Venkataraman, M.D., Breier, J.I., Wheless, J.W., Papanicolaou, A.C. Mapping of expressive language cortex using Magnetic Source Imaging. Neurocase,  7: 419-422, 2001.

Castillo, E.M., Simos, P.G., Wheless, J.W., Baumgartner, J.E., Breier, J.I., Billingsley, R.L., Sarkari, S., Fitzgerald, M.E., Papanicolaou, A.C.  Integrating sensory and motor mapping in a comprehensive MEG protocol. Clinical validity and replicability. Neuroimage, 21:973-83, 2004.

Ishibashi, H., Simos, P.G., Castillo, E.M., Maggio, W.W., Wheless, J.W., Kim, H.L., Venkataraman, V., Sanders, D.K., Breier, J.I., Zhang, W., Davis, R.N., Papanicolaou, A.C. Detection and significance of focal, interictal slow wave activity for localization of the primary epileptogenic region using magnetoencephalography. Journal of Neurosurgery, 96:724-730: April 2002.

Ishibashi, H., Simos, P.G., Castillo, E.M., Maggio, W.W., Wheless, J.W., Kim, H.L., Venkataraman, V., Sanders, D.K., Breier, J.I., Zhang, W., Davis, R.N., and Papanicolaou, A.C.  Detection and significance of focal, interictal slow wave activity for localization of the primary epileptogenic region using magnetoencephalography.  Epilepsia, 42 (Suppl. 7):272, 2001.

Ishibashi, H., Simos, P.G., Fletcher, J.M., Wheless, J.W., Baumgartner, J., Kim, H.L., Davis, R.N., Zhang, W., & Papanicolaou, A.C.  Multimodality functional imaging evaluation in a patient with rasmussen’s encephalitis.  Brain and Development, 24:239-244, June 2002.

Ishibashi, H., Simos, P.G., Wheless, J.W., Baumgartner, J.E., Kim, H.L., Castillo, E.M., Davis, R.N., and Papanicolaou, A.C.  Localization of ictal and interictal bursting epileptogenic activity in focal cortical dysplasia: Agreement of Magnetoencephalography and electrocorticography.  Neurological Research, 24(6): 525-30, September 2002.

Ishibashi, H., Simos, P.G., Wheless, J.W., Zhang, W., Baumgartner, J.E., Castillo, E.M., & Papanicolaou, A.C.  Somatosensory evoked magnetic field in hemimegalencephaly.  Neurological Research, 24: 459-462, July 2002.

Leon-Carion, J., Simos, P.G., Breier, J.I., & Zouridakis, G., Papanicolaou, A.C.: Imagenes de activacion functional cerebral a traves de medidas de fuentes magneticas: Applicationes de la magnetoencephalografia a la Neuropsicologia (Functional brain imaging through magnetic fields: Applications of Magnetoencephalography in neuropsychology) Revista de Psychologia General y Aplicada (Spain), 55, 105-112: 2002.

Maggio, W.W., Simos, P.G., Breier, J.I., Zouridakis, G., Gormley, W.B., Constantinou, J.E.C., Wheless, J.W., Papanicolaou, A.C. Speech mapping with magnetic source imaging: comparison with intraoperative speech mapping. Epilepsia, 40 (Suppl. 2): 50, 1999.

Maggio, W.W., Simos, P.G., Breier, J.I., Zouridakis, G., Gormley, W.B., Constantinou, J., Wheless, J.W., Papanicolaou, A.C.  Magnetic source imaging speech mapping:  comparison with interoperative speech mapping.  Epilepsia, 40 (Suppl. 7): 181, 2000.

Papanicolaou AC., Pataraia, E., Billingsley-Marshall, R.L., Castillo, E.M., Wheless, J.M., Swank, P.R., Breier, J.I., Sarkari, S., & Simos, P.G. Toward the substitution of invasive electroencephalography in epilepsy surgery.  Journal of Clinical Neurophysiology, 22(4):231-237, 2005.

Papanicolaou, A.C., Simos, P.G., Breier, J.I., Castillo, E., & Davis, R. Language mapping with magnetoencephalography (MEG) yields results comparable to the Wada test. Journal of the International Neuropsychological Society, 8: 216-217, 2002.

Papanicolaou, A.C., Simos, P.G., Breier, J.I., Castillo, E.M., Davis, R.N., Wheless, J. W., Venkataraman, V., Kim, H.L., and Maggio, W.W.  MEG:  A method comparable to the Wada procedure for language laterality assessment.  Epilepsia 42 (Suppl. 7): 75, 2001.

Papanicolaou, A.C., Simos, P.G., Breier, J.I., Wheless, J.W., Mancias, P., Baumgartner, J.E., Maggio, W.W., Gormley, W., Constantinou, J.E.C., & Butler, I.I.  Brain plasticity for sensory and linguistic functions: a functional imaging study using MEG with children and young adults.  Journal of Child Neurology, 16: 241-252; 2001.

Papanicolaou, A.C., Simos, P.G., Breier, J.I., Zouridakis, G., Constantinou, J.E., Wheless, J.W., Maggio, W.W.  Applications of MEG to the mapping of the language-Specific cortex.  Epilepsia, 40, (Suppl. 7): 179, 2000.

Papanicolaou, A.C., Simos, P.G., Breier, J.I., Zouridakis, G., Wilmore, L.J., Wheless, J.W., Constantinou, J.C., Gormley, W., Maggio, W.W. Magnetoencephalographic mapping of the language specific cortex. Journal of Neurosurgery, 90:85-93, 1999.

Papanicolaou, A.C., Simos, P.G., Castillo, E.M., Breier, J.I., & Wright, A.A. The hippocampus and memory of verbal and pictorial material. Learning and Memory, 9(3):99-104. 2002.

Papanicolaou, A.C., Simos, P.G., Castillo, E.M., Breier, J.I., Sarkari, S., Pataraia, E., Billingsley, R.L., Buchanan, S., Wheless, J., Maggio, V., Maggio, W.W. Magnetoencephalography: A non-invasive alternative to the Wada procedure.  Journal of Neurosurgery, 100, 867-76, 2004.

Papanicolaou, A.C., Simos, P.G., Zouridakis, G., Breier, J.I, Gormley, W.B., Constantinou, J.E., Wheless, J.W., Maggio, W.W. Mapping the Language Cortex with MSI. Epilepsia, 40 (Suppl. 2): 50-51, 1999.

Papanicolaou, A.C., Simos, P.G., Zouridakis, G., Kataki, M.  The brain mechanisms of receptive language imaging through magnetoencephalography. Egkefalos, 36, 120-135-1999.

Pataraia E, Billingsley-Marshall RL, Castillo EM, Breier JI, Simos PG, Sarkari S, Fitzgerald M, Clear T, Papanicolaou AC.  Organization of receptive language-specific cortex before and after left temporal lobectomy.  Neurology, 64: 481-487, 2005.

Pataraia, P.G. Simos, E.M. Castillo, R.L. Billingsley-Marshall, A.L. McGregor, J.I. Breier, S. Sarkari, A.C. Papanicolaou. Reorganization of language- specific cortex in patients with lesional or mesial temporal epilepsy. Neurology 8; 64(3):481-487, 2005. 

Pataraia, E., Simos, P.G., Castillo, E.M., Billingsley, R.L., Sarkari, S., Swank, P.R., Breier, J.I., Maggio, V., Wheless, J.M., & Papanicolaou AC. Does magnetoencephalography add to scalp video-EEG as a diagnostic tool in epilepsy surgery? Neurology, 62 (6):943-948, 2004.

Simos, P. G., Papanicolaou, A.C., Breier, J.I., Fletcher, J.M., Wheless, J.W., Maggio, W.W., Gormley, W., Constantinou, J.C.  Insights Into Brain Function and Neural Plasticity using Magnetic Source Imaging.  Journal of Clinical Neurophysiology, 17(2) 143-162, 2000.

Simos, P.G., Breier, J.I., Maggio, W.W., Gormley, W., Zouridakis, G., Wilmore, L.J., Wheless, J.W., Papanicolaou, A.C. Atypical temporal lobe language representation revealed by MEG and intraoperative stimulation mapping. Neuroreport, 10:139-142, 1999.

Simos, P.G., Castillo, E.M., Fletcher, J.M., Francis, D.J., Maestu, F., Breier, J.I., Maggio, W.W., & Papanicolaou, A.C. Mapping of receptive language cortex in bilinguals using Magnetic Source Imaging. Journal of Neurosurgery 95:76-81, 2001.

Simos, P.G.; Papanicolaou, A.C.; Breier, J.I.; Wilmore, L.J.; Wheless, J.W.; Constantinou, J.C.; Gormley, W.; Maggio, W.W. Localization of language-specific cortex using MEG and intraoperative stimulation mapping. Journal of Neurosurgery, 91: 787-796, 1999.

Simos, P. G., Sarkari, S., Castillo, E.M., Billingsley-Marshall, R. L, Pataraia, E., Clear, T. & Papanicolaou, A. C. Reproducibility of measures of neurophysiological activity in Wernicke’s area: A magnetic source imaging study. Clinical Neurophysiology,116 (10): 2381-91.

Valaki CE, Maestu F, Simos PG, Zhang W, Fernandez A, Amo C, Ortiz T, Papanicolaou AC. Cortical organization for receptive language functions in Chinese: A Cross-linguistic study using MEG. Neuropsychologia, 42:967-79, 2004.

Wheless JW, Castillo E, Maggio V, Kim HL, Breier JI, Simos PG, & Papanicolaou AC. Magnetoencephalography (MEG) and Magnetic Source Imaging (MSI). Neurologist, 10, 138-53, 2004.

Wheless, J.W., Breier, J.I., Simos, P.G., Constantinou, J.E.C., Baumgarter, J.E., Venkatarman, V., & Papanicolaou, A.C. A comparison of language dominance in children as determined by magnetic source imaging and the intracarotid amobarbital procedure. Epilepsia.  41(Suppl. 7): 81, 2000.

Wheless, J.W., Willmore, L.J., Breier, J.I., Kataki, M., Smith, J.R., King, D.W., Meador, K.J., Park, Y.D., Loring, D.W., Clifton, G.L., Baumgartner, J., Thomas, A.B., Constantinou, J.E.C., Papanicolaou, A.C. A comparison of magnetoencephalography, MRI and V-EEG in patients evaluated for epilepsy surgery. Epilepsia, 40(7):931-41, 1999.

Zhang W., MD, PhD, Simos, P.G., MD, PhD, Ishibashi, H., MD, PhD, Wheless, J.W., MD, Maggio, W.W., MD, Castillo E.M., PhD, Baumgartner, J.E, MD, Breier J, PhD, Papanicolaou A.C. PhD. MEG assists in finding subtle cortical dysplasia.  Epilepsia, 43: 78, 2002.

Zhang W., Simos P.G., Ishibashi H., Wheless J.W., Castillo, E.M., Maggio W.W., Baumgartner, J.E., Breier, J.I., Sarkari, S., and Papanicolaou, A.C. Multimodality neuroimaging evaluation improves the detection of subtle cortical dysplasia associated epilepsy. Neurological Research, 25(1):53-57, January 2003.

Zhang, W., Qi, J., Papanicolaou, A.C. Functional Neuroimaging--Application of Magnetoencephalography on Language Mapping, Guo Wai Yi Xue Fang She Xue Fen Ce (Chinese) Foreign Medical Sciences Clinical Radiology Fascicle, 2002, 25(4):212-215.

Presentations

Breier, J.I., Simos, P.G., Castillo, E.M., Pataraia, E., Billingsley, R.L., Wheless, J.W., and Papanicolaou, A.C.  Abnormal Activation of Language Cortex in Patients With Chronic Seizures and Academic Achievement Deficit.  American Epilepsy Society, 58^th Annual Meeting, New Orleans, December 5-8, 2004.

Breier, J.I., Simos, P.G., Castillo, E.M., Pataraia, E., Billingsley, R.L., Wheless, J.W., and Papanicolaou, A.C.  Abnormal Activation of Language Cortex in Patients With Chronic Seizures and Academic Achievement Deficit.  American Epilepsy Society, 58^th Annual Meeting, New Orleans, December 5-8, 2004. 

Breier, J.I., Wheless, J.W., Simos, P.G., Constantinou, J.E.C., Baumgarter, J.E., Venkatarman, V., & Papanicolaou, A.C. Language dominance in children as determined by magnetic source imaging and the intracarotid amobarbital procedure: A comparison. Paper presented at the 29^th Annual Meeting of the Child Neurology Society. St. Louis, MO, October 25 – 28, 2000.

Breier, J.I., Wheless, J.W., Simos, P.G., Constantinou, J.E.C., Baumgarter, J.E., Venkatarman, V., & Papanicolaou, A.C. Language dominance in children as determined by magnetic source imaging and the intracarotid amobarbital procedure: A comparison. Paper presented at the 29^th Annual Meeting of the Child Neurology Society. St. Louis, MO, October 25 – 28, 2000.

Castillo, E.M., Breier, J.I., Wheless, J.W., Slater, J.D., Tandon, N., Baumgartner, J.E., McManis, M.H., Papanicolaou, A.C.  Contributions of Direct Cortical Stimulation and MEG Recordings to Identify “Essential” Language Cortex.  American Epilepsy Society and American Clinical Neuropsychology Society Joint Annual Meeting, Washington, DC, December 206, 2005.

Castillo, E.M., Breier, J.I., Wheless, J.W., Slater, J.D., Tandon, N., Baumgartner, J.E., McManis, M.H., Papanicolaou, A.C.  Contributions of Direct Cortical Stimulation and MEG Recordings to Identify “Essential” Language Cortex.  American Epilepsy Society and American Clinical Neuropsychology Society Joint Annual Meeting, Washington, DC, December 206, 2005.

Castillo, E.M., Simos, P.G., Breier, J.I., Wheless, J.W., Butler, I.J., Billingsley, R.L., Papanicolaou, A.C. Epileptic activity interfering with word processing in landau-kleffer syndrome: the role of the non-affected hemisphere in linguistic deficit manifestation. Paper presented at the Annual meeting of the American Epilepsy Society, Boston, MA., Dec. 5 – 10.

Castillo, E.M., Breier, J.I., Wheless, J.W., Baumgartner, J.E., Pataraia, E., Papanicolaou, A.C.  Is linguistic function still there after multiple subpial transactions over Wernicke’s area?  American Epilepsy Society, 58^th Annual Meeting, New Orleans, December 3-8, 2004.

Castillo, E.M., Breier, J.I., Wheless, J.W., Baumgartner, J.E., Pataraia, E., Papanicolaou, A.C.  Is linguistic function still there after multiple subpial transactions over Wernicke’s area?  American Epilepsy Society, 58^th Annual Meeting, New Orleans, December 3-8, 2004.

Castillo, E.M., Breier, J.I., Wheless, J.W., Pataraia, E., Papanicolaou, A.C.  Planning epilepsy surgery when language is compromised: comparisons of MEG-derived maps of activation with the Wada test and with direct electrical stimulation mapping.  6^th European Congress on Epileptogology.  Vienna, Oral presentation platform.  May30th – June 3^rd, 2004.

Castillo, E.M., Breier, J.I., Wheless, J.W., Pataraia, E., Papanicolaou, A.C.  Planning epilepsy surgery when language is compromised: comparisons of MEG-derived maps of activation with the Wada test and with direct electrical stimulation mapping.  The 6^th European Congress on Epileptology, Vienna.  May 30^th – June 3^rd, 2004.

Castillo, E.M., Simos, P.G., Wheless, J.W., Baumgartner, J.E., Breier, J.I., Sarkari, S., Fitzgerald, M.E., Papanicolaou, A.C.  Mapping sensorimotor function in patients with perirolandic lesions: a comprehensive MEG protocol.  14^th International Conference on Biomagnetism, Boston, August 8-12, 2004.

Davis, R.N., Castillo, E.M., Simos, P.G., Breier, J.I., and Papanicolaou, A.C. Language mapping using MSI: An overview poster presented at the Sixth Annual Public Forum for Brain Awareness Week, Houston, TX.  March, 2001.

Davis, R.N., Castillo, E.M., Simos, P.G., Breier, J.I., and Papanicolaou, A.C. Language mapping using MSI: An overview poster presented at the Sixth Annual Public Forum for Brain Awareness Week, Houston, TX.  March, 2001.

Maggio, W.W.; Simos, P.G.; Breier, J.I.; Zouridakis, G.; Gormley, W.B.; Constantinou, J.E.C.; Wheless, J.W.; Papanicolaou, A.C. Magnetic Source Imaging Speech Mapping: Comparison with Intraoperative Speech Mapping. Paper presented at the annual meeting of the Rocky Mountain Association, 1999.

Papanicolaou, A.C., Simos, P.G., Castillo, E.M., Breier, J.I., Wheless, J.W., Maggio, V., Billingsley, R.L., Sarkari, S., Pataraia, E., Clear, T., Maggio, W.W.  MEG is comparable to the Wada procedure for language laterality assessment. Presented at the Annual meeting of the American Epilepsy Society, Boston, MA, December, 5–10, 2003.

Pataraia, E., Billingsley-Marshall, R.L., Castillo, E.M., Breier, J.I., Simos, P.G., Sarkari, S., Fitzgerald, M., Clear, T., and Papanicolaou, A.C.  Organization of receptive language-specific cortex before and after left temporal lobectomy. American Epilepsy Society, 58^th Annual Meeting, New Orleans, December 5-8, 2004.

Pataraia, E., Castillo, E.M., Simos, P.G., Billingsley-Marshall, R.L., Sarkari, S., Breier, J.I., Papanicolaou, A.C. Relative merits of MEG for identification of the epileptogenic zone as compared with invasive EEG. 14^th International Conference on Biomagnetism, Boston, August 8-12, 2004.

Pataraia, E., Simos, P.G., Billingsley, R.L., Castillo, E.M., Sarkari, S., Maggio, V., Wheless, J.W., Fitzgerald, M., Breier, J.I., Papanicolaou, A.C. Contribution of magnetoencephalography to the presurgical determination of the epileptogenic zone in patients with frontal lobe epilepsy. Paper presented at the Annual meeting of the American Epilepsy Society, Boston, MA, December 5–10, 2003.

Pataraia, E., Simos, P.G., Billingsley-Marshall, R.L., Castillo, E.M., Breier, J.I., Sarkari, S., Papanicolaou, A.C.  Assessment of the localization accuracy of magnetoencephalography in temporal lobe epilepsy – comparison with invasive EEG.  American Epilepsy Society and American Clinical Neurophysiology Society Joint Annual Meeting, Washington DC, December 2-6, 2005.

Perkins, F.F., Clarke, D.F., Breier, J.I., Chacon, M.M., Castillo, E.M., Weers, D., Wheless, J.W.  Benign Rolandic Epilepsy: Neuropsychological Testing and Magnetic Source Imaging Analysis.  American Epilepsy Society, 58^th Annual Meeting, New Orleans, December 5-8, 2004. 

Slater, J.D., McManis, M.H., Clarke, D., Perkins, F.F., McGregor, A.L., Wheless, J.W., Breier, J.I., Castillo, E.M., Papanicolaou, A.C.  Magnetic source localization in patients with idiopathic generalized epilepsies.  American Epilepsy Society and American Clinical Neurophysiology Society Joint Annual Meeting, Washington DC, December 2-6, 2005.

Zhang W., MD, PhD, Simos, P.G., MD, PhD, Ishibashi, H., MD, PhD, Castillo E.M., PhD, Breier J, PhD, Baumgartner, J.E, MD, Wheless, J.W., MD, Papanicolaou A.C. PhD. Neuroimaging Features of Epidermal Nevus Syndrome, ASNR (American Society of Neuroradiology) 40th Annual Meeting,  Vancouver, Canada, May 13-17, 2002.

Zhang W., MD, PhD, Simos, P.G., MD, PhD, Ishibashi, H., MD, PhD, Castillo E.M., PhD, Breier J, PhD, Baumgartner, J.E, MD, Wheless, J.W., MD, Papanicolaou A.C. PhD. Neuroimaging Features of Epidermal Nevus Syndrome, ASNR(American Society of Neuroradiology) 40th Annual Meeting,  Vancouver, Canada, May 13-17, 2002.