Deep brain stimulation (DBS) involves high-frequency electrical stimulation of a specific site within the brain via implanted unilateral or bilateral electrodes that are connected to a pulse generator implanted in the chest. DBS is used in the treatment of intractable movement disorders characterized by involuntary tremors or muscle contractions.

Medically Necessary:

Unilateral or bilateral deep brain stimulation is considered medically necessary for individuals with disabling, medically unresponsive Parkinson's disease who meet the following criteria:

• A minimal score of 30 points on the motor portion of the Unified Parkinson's Disease Rating Scale when the individual has been without medication for 12 hours; and
• Motor complications of therapy that cannot be controlled pharmacologically.

Unilateral or bilateral deep brain stimulation is considered medically necessary for individuals with medically refractory essential tremor.

Unilateral or bilateral deep brain stimulation of the subthalamic nucleus or globus pallidus is considered medically necessary for individuals who are seven (7) years of age and older with primary dystonia and who have ALL of the following:

• Dystonia is chronic, refractory to drugs, and has a significant effect upon daily activity, AND
• Dystonia is not due to a secondary cause such as stroke, cerebral palsy, tumor, trauma, infection, multiple sclerosis, other neurodegenerative diseases, or medications, AND
• Dystonia manifests as one or more of the following:
  • Cervical dystonia (torticollis), OR
  • Segmental dystonia, OR
  • Generalized dystonia, OR
  • Hemidystonia.

Investigational and Not Medically Necessary:

Deep brain stimulation for tremor and dystonia from other causes such as trauma, multiple sclerosis (MS), degenerative disorders, metabolic disorders, infectious diseases, and drug-induced movement disorders is considered investigational and not medically necessary.

Deep brain stimulation is considered investigational and not medically necessary for all other conditions not identified as medically necessary, including, but not limited to, the treatment of epilepsy, chronic cluster headache, obsessive-compulsive disorder (OCD)  and Tourette syndrome.

The use of cerebellar stimulation/pacing is considered investigational and not medically necessary.

A variety of randomized studies have shown that deep brain stimulation implanted in a variety of locations in the globus pallidus, subthalamic nucleus or thalamus improved the symptoms of medically refractory Parkinson's disease compared either to sham stimulation or pallidotomy. Additionally, a randomized controlled study has shown that deep brain stimulation of the thalamus improves the symptoms of essential tremor compared to sham stimulation (Deuschl, 2000; Figuerias-Mendez, 2002; Merello, 1999; Obeso, 2001; Rehncrona, 2003).

Primary (or idiopathic) dystonia is dystonia that is not due to a secondary cause such as stroke, cerebral palsy, tumor, trauma, infection, multiple sclerosis, medications, or a neurodegenerative disease. In 2003, the Activa® Dystonia Therapy System (Medtronic, Minneapolis, MN) was granted a Humanitarian Devices Exemption (HDE) by the U.S. Food and Drug Administration (FDA) to for the treatment of primary dystonia. The FDA's decision was based on the results of deep brain stimulation in 201 individuals represented in 34 manuscripts. There were 3 studies that reported at least 10 cases of primary dystonia. In these studies, clinical improvement ranged from 50% to 88%. A total of 21 children were studied; 81% were older than 7 years. Among these individuals there was about a 60% improvement in clinical scores. The FDA analysis of risk and probable benefit indicated that the only other treatment options for chronic refractory primary dystonia are neurodestructive procedures and DBS provides a reversible alternative.

The FDA Summary of Safety and Probable Benefit states:

Limited treatment strategies exist for chronic, intractable (drug refractory) primary dystonia, including generalized and/or segmental dystonia, hemidystonia, and cervical dystonia (torticollis). The three main approaches to the treatment of primary dystonia include systemic pharmacological agents (oral medications), local pharmacological agents (injected directly into affected muscles or their nerve supply), and destructive surgical or neurosurgical intervention. When local injection therapy is impractical or unsafe, and when systemic medications are not effective or produce unacceptable side effects, surgery may be considered. Surgical treatments of dystonia, including ablative therapies such as thalamotomies and pallidotomies, are irreversible, destructive procedures that can be associated with disabling complications. The patient group characterized in the Humanitarian Use Device application may also be candidates for deep brain stimulation therapy. Although there are a number of serious adverse events experienced by patients treated with deep brain stimulation, in the absence of therapy, chronic intractable dystonia can be very disabling and in some cases, progress to a life threatening stage or constitute a major fixed handicap. When the age of dystonia occurs prior to the reaching their full adult size, the disease not only can affect normal psychosocial development (due to ostracization and/or prevention of normal peer relationships), but also cause irreparable damage to the skeletal system. As the body of the individual is contorted by the disease, the skeleton may be placed under constant severe stresses which may cause permanent disfigurement.

Risks associated with DBS therapy for dystonia appear to be similar to the risks associated with the performance of stereotactic surgery and the implantation of DBS systems for currently approved indications (Parkinson's Disease and Essential Tremor), except for when used in either child or adolescent patient groups. These additional risks include the use of general anesthetic instead of local anesthesia during implantation, potential lead strains or fractures related to elongation of the trunk of the patient (due to normal growth) while the length of implanted conductor (from the neurostimulator to the burr hole) remains fixed, the risk of lead migration due to patient head growth resulting in ineffective stimulation and the added risk of children being engaged in active play and sports activities that could damage components of the implanted system. The risks of lead strain, fracture and migration can be minimized by evaluating the patient's implanted lead/extension assembly for sufficient strain relief at regular post-implant follow-up sessions and by considering the replacement of the extension with one of greater length during other elective surgery procedures, such as during the regular change out of neurostimulators that must occur because of battery depletion. In cases where lead tip displacement may occur due to cranial growth the lead tip migration may be accommodated through reprogramming due to the number and spacing of the electrode contacts.

Therefore, it is reasonable to conclude that the probable benefit to health from using the device for the target population outweighs the risk of illness or injury, taking into account the probable risks and benefits of currently available devices or alternative forms of treatment when used as indicated in accordance with the directions for use.

Other proposed applications:
Obsessive compulsive disorder (OCD)
On February 19, 2009 the Reclaim™ device (Metronic Neuro, Minneapolis, MN) received U.S. Food and Drug Administration (FDA) approval under the Humanitarian Devices Exemption (HDE) process. The FDA labeling states that the device is indicated for bilateral stimulation of the anterior limb of the internal capsule (AIC), as an adjunct to medications and as an alternative to anterior capsulotomy for treatment of chronic, severe, treatment-resistant obsessive compulsive disorder (OCD) in adults who have failed at least three selective serotonin reuptake inhibitors (SSRIs).

As part of a clinical trial, Mallet and colleagues (2008) reported preliminary findings of a crossover, double-blind, multicenter study of DBS for treatment of refractory obsessive-compulsive disorder (OCD). Eighteen individuals were enrolled, one withdrew and one required removal of the stimulator before randomization because of infection. Three months after surgery, 8 individuals were randomly assigned to receive active stimulation for 3 months, followed by 1 month of washout, then 3 months of sham stimulation (on-off group). The other group followed the same treatment schedule in reverse (off-on group). New or worsening symptoms were classified as adverse events. It was recommended that medical treatment remain stable and adjustments necessitated by the individual's psychiatric condition were recorded. Medication was held constant during the 10-month protocol, except for transient increase in benzodiazepine therapy in 3 individuals and augmentation of neuroleptic treatment in one individual for exacerbated anxiety. The primary outcome measure was severity of OCD as assessed by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) measured at the end of each period. The Y-BOCS score was significantly lower at the end of active stimulation than at the end of the sham stimulation (mean score, 19 +/- 8 vs. 28 +/- 7; p=0.01) independent of the group and the period. No significant carryover effect between treatment phases was detected. Individuals who had active stimulation first (on-off group) tended to have a larger treatment effect than the off-on group (p=0.06).  Outcomes on secondary measures of global health and functioning were significantly better at the end of the stimulation period. Scores on Montgomery and Asberg Depression Scale (MADRS), Brief Scale for Anxiety, neuropsychological ratings, and self-reported disability (Sheehan Disability Scale) did not differ significantly at the end of treatment and sham sessions. Fifteen serious adverse events were reported in 11 individuals, the most serious a parenchymal brain hemorrhage. Transient motor and psychiatric symptoms induced by active stimulation resolved spontaneously or with adjustment of stimulation settings. Seven behavioral adverse events were reported in 5 individuals during stimulation. Hypomania was the main psychiatric serious adverse event; symptoms resolved with adjustment of stimulation settings. The authors note that the multicenter design might be a limitation of the study because of variation in targeting of stimulation. In addition, in order to preserve blinding, stimulation settings were kept below the threshold known to induce adverse effects and may have been too low to reduce symptoms. The authors concluded that these preliminary findings suggest that stimulation of the subthalamic nucleus may reduce the symptoms of severe forms of OCD but it is associated with a substantial risk of serious adverse events.

In psychosurgery, there has been a shift of interest away from ablative techniques and toward deep brain stimulation. Studies of DBS for depression and obsessive compulsive disorder, however, are few and involve small numbers of subjects (Sachdev, 2009).

Deep brain stimulation is also being studied as a treatment for tremors from other causes including, but not limited to, multiple sclerosis (MS), trauma and degenerative disorders. In addition, DBS is being investigated to determine if functional improvement is achieved and maintained for other conditions such as chronic cluster headache, epilepsy and Tourette syndrome. 

Cerebellar stimulation/pacing is electrical stimulation using surgically implanted electrodes on the surface of the cerebellum and has been proposed as one way to treat some neurological disorders.  At this time, there is inadequate information available to make an assessment of the clinical usefulness of this procedure.

Deep brain stimulation (DBS) has been investigated as an alternative to permanent neuroablative procedures, such as thalamotomy and pallidotomy. The technique has been most thoroughly investigated as an alternative to thalamotomy for unilateral control of essential tremor, and tremor associated with Parkinson's disease (PD). DBS has also been investigated in individuals with primary dystonia, defined as a neurological movement disorder characterized by involuntary muscle contractions, which force certain parts of the body into abnormal, contorted and painful movements or postures and unrelated to any other neurological condition. Treatment options for dystonia include oral or injectable medications (i.e., botulinum toxin) and destructive surgical or neurosurgical interventions (i.e., thalamotomies or pallidotomies) when conservative therapies fail.

Deep brain stimulation involves the stereotactic placement of an electrode into the brain (i.e., thalamus, globus pallidus, or subthalamic nucleus). The electrode is initially attached to a temporary transcutaneous cable for short-term stimulation to validate treatment effectiveness. Several days later, the individual returns to surgery for permanent subcutaneous implantation of the cable and a radiofrequency-coupled or battery-powered programmable stimulator. The electrode is typically implanted unilaterally on the side corresponding to the most severe symptoms. However, the use of bilateral stimulation using two electrode arrays has also been investigated in individuals with bilateral, severe symptoms.

After implantation, noninvasive programming of the neurostimulator can be adjusted to the individual's symptoms. This feature may be important for individuals with PD, whose disease may progress over time, requiring different neurostimulation parameters. Setting the optimal neurostimulation parameters may involve the balance between optimal symptom control and appearance of side effects of neurostimulation, such as dysarthria, disequilibrium, or involuntary movements.

Cerebellar stimulation/pacing: a proposed treatment of neurological disorders that involves electrical stimulation of the cerebellum part of the brain

Dystonia: covers a diverse group of movement disorders, all of which are characterized by involuntary muscle contractions that may cause twisting and repetitive movements or abnormal postures; dystonia is the most severe form of a group of movement disorders called dyskinesias

Essential tremor (ET): a chronic, incurable condition with unknown cause characterized by involuntary, rhythmic tremor of a body part, most typically the hands and arms

Globus pallidus interna (GPi): a part of the brain involved with movement

Humanitarian Device Exemption (HDE): similar to a premarket approval (PMA) application, but is exempt from the effectiveness requirements of a PMA. An HDE application is not required to contain the results of scientifically valid clinical investigations demonstrating that the device is effective for its intended purpose and does not pose an unreasonable or significant risk of illness or injury. The use of the device is limited to 4000 or less individuals per year

Multiple sclerosis: a condition of the nervous system that results in a wide variety of symptoms

Parkinson's disease: a progressive, incurable disease caused by the slow continuous loss of nerve cells in the part of the brain that controls muscle movement

Post-traumatic dyskinesia: a condition where movement is altered or absent due to a traumatic injury

Primary dystonia: is not due to a secondary cause such as stroke, cerebral palsy, tumor, trauma, infection, multiple sclerosis, medications, or a neurodegenerative disease

Secondary dystonia: is associated with a known, acquired cause or additional neurologic abnormality where symptoms of involuntary muscle contractions are related to other conditions such as stroke, trauma, toxic substance exposure or asphyxia

Subthalamic nucleus (STN): a part of the brain involved with movement

Unified Parkinson's Disease Rating Scale (UPDRS):  UPDRS is a rating tool to follow the longitudinal course of Parkinson's Disease that is made up of three sections: 1) mentation, behavior and mood, 2) activities of daily living and 3) motor sections evaluated by interview

Ventralis intermediate nucleus of the thalamus (Vim): a part of the brain involved with movement

The following codes for treatments and procedures applicable to this document are included below for informational purposes.  Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy.  Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

When services may be Medically Necessary when criteria are met:

When services are Investigational and Not Medically Necessary:

For the procedure and diagnosis codes listed above when criteria are not met, for deep brain stimulation for all other diagnoses not listed; or when the code describes a procedure indicated in the Position Statement section as investigational and not medically necessary.

When Services are also Investigational and Not Medically Necessary:

Peer Reviewed Publications:

1. Cif L, El Fertit H, Vayssiere N, et al. Treatment of dystonic syndromes by chronic electrical stimulation of the internal globus pallidus. J Neurosurg Sci. 2003; 47(1):52-55.
2. Deuschl, G, Wenzelburger R, Loffler K, et al. Essential tremor and cerebellar dysfunction clinical and kinematic analysis of intention tremor. Brain. 2000; 123(Pt 8):1568-1580.
3. Fields JA, Troster AI, Woods SP, et al. Neuropsychological and quality of life outcomes 12 months after unilateral thalamic stimulation for essential tremor. J Neurol Neurosurg Psychiatry. 2003; 74(3):305-311.
4. Figuerias-Mendez R, Regidor I, Riva-Meana C, Magarinos-Ascone CM.  Further supporting evidence of beneficial subthalamic stimulation in Parkinson's patients. Neurology. 2002; 58(3):469-470.
5. Fraix V, Houeto JL, Lagrange C, et al. Clinical and economic results of bilateral subthalamic nucleus stimulation in Parkinson's disease. J Neurol Neurosurg Psychiatry. 2006; 77(4):443-449.
6. Goetz CG, Poewe W, Rascol O, et al. Movement Disorder Society Task Force report on the Hoehn and Yahr staging scale: status and recommendations. Mov Disord. 2004; 19(9):1020-1028.
7. Goetz CG, Poewe W, Rascol O, Sampaio C. Evidence-based medical review update: pharmacological and surgical treatments of Parkinson's disease: 2001 to 2004. Mov Disord. 2005; 20(5):532-539.
8. Goetz CG, Tilley BC, Shaftman SR, et al. Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS): scale presentation and clinimetric testing results. Mov Disord. 2008; 23(15):2129-2170. 
9. Levine CB, Fahrbach KR, Siderowf AD, et al. Diagnosis and treatment of Parkinson's Disease: a systematic review of the literature. Evid Rep Technol Assess (Summ). 2003; (57):1-4.
10. Mallet L, Polosan M, Jaafari N et al. Subthalamic nucleus stimulation in severe obsessive-compulsive disorder. N Engl J Med 2008; 359(20):2121-2134.
11. Merello M, Nouzeilles MI, Kuzis G, et al. Unilateral radiofrequency lesion versus electrostimulation of posteroventral pallidum: a prospective randomized comparison. Mov Disord. 1999; 14(1):50-56.
12. Obeso J , Guridi J, Rodriguez-Oroz M. et al. Deep brain stimulation of the subthalamic nucleus or the par interna of the globus pallidus in Parkinson's Disease. Deep Brain Stimulation for Parkinson's Disease Study Group. NEJM. 2001; 345(13):956-963.
13. Olanow CW, Watts RL, Koller WC. An algorithm (decision tree) for the management of Parkinson's disease (2001): treatment guidelines. Neurology. 2001; 56(11 Suppl 5):S1-S88.
14. Ondo W, Almaguer M, Jankovic J, Simpson RK. Thalamic deep brain stimulation: comparison between unilateral and bilateral placement. Arch Neurol. 2001; 58(2):218-222.
15. Pahwa R, Lyons KL, Wilkinson SB, et al. Bilateral thalamic stimulation for the treatment of essential tremor. Neurology. 1999; 53(7):1447-1450.
16. Piper M, Abrams GM, Marks WJ Jr. Deep brain stimulation for the treatment of Parkinson's disease: overview and impact on gait and mobility. NeuroRehabilitation. 2005; 20(3):223-232.
17. Portman AT, van Laar T, Staal MJ, et al. Chronic stimulation of the subthalamic nucleus increases daily on-time without dyskinesia in advanced Parkinson's disease. Parkinsonism Relat Disord. 2006; 12(3):143-148.
18. Rehncrona S, Johnels B, Widner H, et al. Long-term efficacy of thalamic deep brain stimulation for tremor: double-blind assessments. Mov Disord. 2003; 18(2):163-170.
19. Sachdev PS, Chen X. Neurosurgical treatment of mood disorders: traditional psychosurgery and the advent of deep brain stimulation. Curr Opin Psychiatry 2009; 22(1):25-31.
20. Schuurman PR, Bosch DA, Bossuyt PM, et al. A comparison of continuous thalamic stimulation and thalamotomy for suppression of severe tremor. N Engl J Med. 2000; 342(7):461-468.
21. Servello D, Porta M, Sassi M, et al. Deep brain stimulation in 18 covered individuals with severe Gilles de la Tourette syndrome refractory to treatment: the surgery and stimulation. J Neurol Neurosurg Psychiatry. 2008; 79(2):136-142.
22. Vidailhet M, Vercueil L, Houeto JL, et al. Bilateral deep-brain stimulation of the globus pallidus in primary generalized dystonia. N Engl J Med. 2005; 352(5):459-467.
23. Weaver F, Follett K, Hur K, et al. Deep brain stimulation in Parkinson disease: a metaanalysis of patient outcomes. J Neurosurg. 2005; 103(6):956-967.
24. Welter ML, Mallet L, Houeto JL, et al. Internal pallidal and thalamic stimulation in covered individuals with Tourette syndrome. Arch Neurol. 2008; 65(7):952-957. 

Government Agency, Medical Society, and Other Authoritative Publications:

1. American Academy of Neurology. Evaluation of surgery for Parkinson's disease: a report of the Therapeutics & Technology Assessment Subcommittee of the Task Force on Surgery for Parkinson's Disease. Neurology. 1999; 53(9):1910-1921.
2. American Academy of Neurology. Report of the Quality Standards Subcommittee. Practice parameter: therapies for essential tremor. Available at: http://www.neurology.org/cgi/content/full/64/12/2008. Accessed on February 28, 2010.
3. American Association of Neurological Surgeons. Deep Brain Stimulation. 2007. Available at: http://www.neurosurgerytoday.org/what/patient_e/deep%20brain%20stimulation.asp.  Accessed on March 17, 2010.
4. Blue Cross Blue Shield Association. Bilateral DBS of the subthalamic nucleus or the globus interna for the treatment of advanced Parkinson's Disease. TEC Assessment, 2002; 16(16).
5. Centers for Medicare and Medicaid Services. National Coverage Determination for Deep Brain Stimulation for Essential Tremor and Parkinson's Disease. NCD #160.24. Effective April 1, 2003. Available at: http://www.cms.hhs.gov/mcd/index_list.asp?list_type=ncd. Accessed on February 28, 2010.
6.  Dystonia Medical Research Foundation (DMRF). DBS for dystonia. Available at: http://www.dystonia-foundation.org/pages/deep_brain_stimulation/151.php. Accessed on March 17, 2010.
7. U.S. Food and Drug Administration Center for Devices and Radiological Health. Medtronic Activa® Parkinson's Control Therapy. Premarket Approval. 960009S7. Rockville, MD: FDA. January 14, 2002. Available at:  http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cftopic/pma/pma.cfm?num=p960009S7. Accessed on February 28, 2010.  
8. U.S. Food and Drug Administration Center for Devices and Radiological Health. Humanitarian Device Approval. Medtronic Activa® Dystonia Therapy. H020007. Rockville, MD: FDA. April 15, 2003. Available at: http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cftopic/pma/pma.cfm?num=H020007  .  Accessed on February 28, 2010.
9. U.S. Food and Drug Administration Center for Devices and Radiological Health. Humanitarian Device Approval. Medtronic Reclaim Deep Brain Stimulation for Obsessive Compulsive Disorder (OCD) Therapy H050003. Rockville, MD: FDA. February 4, 2009. Available at: http://www.accessdata.fda.gov/cdrh_docs/pdf5/H050003a.pdf   Accessed on February 28, 2010.

1. National Institute of Neurological Disorders and Stroke (NINDS). National Institutes of Health (NIH). NINDS Dystonias Information Page. Reviewed July 1, 2001. Available at: http://www.ninds.nih.gov/disorders/dystonias/dystonias.htm. Accessed on February 28, 2010.
2. National Library of Medicine. Medical Encyclopedia: Parkinson's disease. http://www.nlm.nih.gov/medlineplus/ency/article/000755.htm. Accessed on February 28, 2010.

Activa® Tremor Control System
Cerebellar Stimulation/Pacemaker
Deep Brain Stimulation for Tremor
Essential Tremor
Parkinson's Disease
Reclaim™

The use of specific product names is illustrative only.  It is not intended to be a recommendation of one product over another, and is not intended to represent a complete listing of all products available.