Magnetoencephalography and Magnetic Source Imaging of the Brain
DESCRIPTION
Magnetoencephalography (MEG) is a noninvasive functional imaging technique in which the weak magnetic forces associated with the electrical activity of the brain are recorded externally on the scalp. Using mathematical modeling, the recorded data are then analyzed to provide an estimated location of the electrical activity. This information can be superimposed on an anatomic image of the brain, typically a magnetic resonance imaging (MRI) scan, to produce a functional/anatomic image of the brain, referred to as magnetic source imaging (MSI).
MEG has been recognized as a non-invasive alternative for the Wada test, also known as an intracarotid sodium amobarbital procedure (ISAP). The Wada test evaluates which hemisphere of the brain controls language in an individual. The test involves a catheter being placed in a carotid artery and injecting sodium amobarbital to one side of the brain, temporarily anesthetizing it. A functional assessment is completed on the non-anesthetized side of the brain and once completed; the procedure is repeated on the other hemisphere.
POLICY
Magnetoencephalography/magnetic source imaging for the purpose of determining the laterality of language function, as a substitute for the Wada test is considered medically necessary if the medical appropriateness criteria are met. (See Medical Appropriateness below.)
Magnetoencephalography/magnetic source imaging for the treatment of other conditions/diseases is considered investigational.
MEDICAL APPROPRIATENESS
Magnetoencephalography/magnetic source imaging for the purpose of determining the laterality of language function, as a substitute for the Wada test is considered medically appropriate for ANY ONE of the following individuals:
An individual being prepared for surgery for epilepsy
An individual being prepared for surgery for brain tumor
An individual being prepared for surgery for other indications requiring a brain resection
IMPORTANT REMINDER
We develop Medical Policies to provide guidance to Members and Providers. This Medical Policy relates only to the services or supplies described in it. The existence of a Medical Policy is not an authorization, certification, explanation of benefits or a contract for the service (or supply) that is referenced in the Medical Policy. For a determination of the benefits that a Member is entitled to receive under his or her health plan, the Member's health plan must be reviewed. If there is a conflict between the Medical Policy and a health plan, the express terms of the health plan will govern.
ADDITIONAL INFORMATION
The lack of randomized controlled trials and studies provide little evidence of the safety and efficacy of magnetoencephalography and magnetic source imaging of the brain for the treatment of other conditions/diseases.
SOURCES
Abou-Khalil, B. (2007). Methods for determination of language dominance: The wada test and proposed alternatives. Current Neurology and Neuroscience Reports, 7 (6), 483-490.
BlueCross BlueShield Association. Medical Policy Reference Manual. (12:2009). Magnetoencephalography/magnetic source imaging (6.01.21). Retrieved January 19, 2011 from BlueWeb. (9 articles and/or guidelines reviewed)
Gumenyuk, V., Roth, T., Moran, J. E., Jefferson, C., Bowyer, S. M., Tepley, N., et al. (2009). Cortical locations of maximal spindle activity: magnetoencephalography (MEG) study. Journal of Sleep Research, 18 (2), 245-253. (Level 4 Evidence - Independent study)
Hayes. Medical Technology Directory. (2008, September). Magnetoencephalography and magnetic source imaging of the brain. Retrieved January 20, 2011 from www.Hayesinc.com/subscribers. (58 articles and/or guidelines reviewed)
Huiskamp, G., Agirre-Arrizubieta, Z., & Leijten, F. (2010). Regional differences in the sensitivity of MEG for interictal spikes in epilepsy. Brain Topography, 23 (2), 159-164. (Level 3 Evidence - Independent study)
Lassonde, M., Sauerein, H.C., Gallagher, A., Theriault, M. & Lapore, F. (2006). Neuropsychology: Traditional and new methods of investigation. Epilepsia, 47 (Suppl. 2), 9-13.
National Guideline Clearinghouse. (2006). ACR appropriateness criteriaŽ epilepsy. Retrieved January 20, 2011 from http://www.guidelines.gov.
National Guideline Clearinghouse. (2009). ACR appropriateness criteriaŽ seizures - child. Retrieved January 20, 2011 from http://www.guidelines.gov.
Pelletier, I., Sauerwein, H. C., Lepore, F., Saint-Amour, D., & Lassonde, M. (2007). Non-invasive alternatives to the wada test in the presurgical evaluation of language and memory functions in epilepsy patients. Epileptic Disorders, 9 (2), 111-126.
Placantonakis, D. G., & Schwartz, T. H. (2009). Localization in epilepsy. Neurologic Clinics, 27 (4), 1015-1030.
Technology Evaluation Center. (2009, January). Special report: MEG and MSI for the purpose of presurgical localization of epileptic lesions - A challenge for technology evaluation. (Vol. 25, No. 8). Chicago: BlueCross BlueShield Association. (22 articles and/or guidelines reviewed)
U. S. Food and Drug Administration. (1997, November). Center for Devices and Radiological Health. 510(k) Premarket Notification Database. K971329. Retrieved January 20, 2011 from http://www.accessdata.fda.gov/cdrh_docs/pdf/K971329.pdf.
ORIGINAL EFFECTIVE DATE: 1/14/2006
MOST RECENT REVIEW DATE: 2/10/2011
ID_BT
Policies included in the Medical Policy Manual are not intended to certify coverage availability. They are medical determinations about a particular technology, service, drug, etc. While a policy or technology may be medically necessary, it could be excluded in a member's benefit plan. Please check with the appropriate claims department to determine if the service in question is a covered service under a particular benefit plan. Use of the Medical Policy Manual is not intended to replace independent medical judgment for treatment of individuals. The content on this Web site is not intended to be a substitute for professional medical advice in any way. Always seek the advice of your physician or other qualified health care provider if you have questions regarding a medical condition or treatment.
This document has been classified as public information.