Transcranial
Magnetic Stimulation
Therapy
The Future Direction of
Neuropsychiatry
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Transcranial Magnetic Stimulation
• Mechanism: To target and modulate neuroplasticity to influence
behavior consequences.
• Neuroplasticity: the brain’s ability to reorganize itself by forming
new neural connections throughout life. It allows the neurons in the
brain to compensate for the injury and disease, and to adjust their
activities in response to new situations or to changes in their
environment.
Transcranial Magnetic Stimulation
• Brain reorganization takes place by
mechanisms such as “axonal sprouting” in
which undamaged axons grow new nerve
endings to reconnect neurons whose links
were injured or severed.
• Undamaged axons can also sprout nerve
endings and connect with other undamaged
nerve cells, forming new neural pathways to
accomplish a needed function.
• In order to reconnect, the neurons need to be stimulated through
activity.
• Neuroplasticity allows us to compensate for irreparably damaged or
dysfunctional neural pathways by strengthening or rerouting our
remaining ones.
Transcranial Magnetic Stimulation
• “Compensatory Masquerade”
brain injury cases, cognitive disability. Allows already-constructed
pathways that neighbor a damaged area to respond to changes in
the body’s demands caused by lost function in some other area.
• “Homologous Region Adoption”
allows one entire brain area to take over functions from distant
brain areas that has been damaged.
• Cross model reassignment
allows the brain of a blind individual in learning to read Braille, to
rewire the sense of touch so it replaces the responsibilities of vision
in the brain areas linked with reading.
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Use it or Lose it!
Neuroplasticity throughout life span: “use it or lose it”
New research indicates that human brain cells are able to
regenerate new brain cells even into the golden years of age
70 and beyond if one’s brain is constantly challenged by and
engaged with a variety of stimulations and new experiences.
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Plasticity
• The capacity of the brain to change with learning is
known as plasticity.
• The brain may change in two aspects:
• 1. internal structure of the
Neurons; area of synapses.
• 2. increases in the number
of synapses between
neurons.
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Faraday’s Principle
• It is the electric stimulation via magnetic induction, not the
magnetic field, that does the effect, thus passing current
through the coil of the wire and then inducing the magnetic
field. Induced currents are critical to the rate of change of the
current, known as “Michael Faraday’s principle”
• I. The rate of change matters. The speed of the current affects the
depolarization of neurons.
• II. Orientation of the coil-critical-neural elements perpendicular to the
plane of the coil, using bidirectional pulses.
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TMS History
• At first, TMS was developed by Barker et al. It was used as a
brain mapping tool, as a tool to measure cortical excitability, as
a probe of neuronal networks, and as a modulator of brain
function.
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Low Frequency vs. High Frequency
TMS
Concept of Depolarization Function
• Low Frequency Stimulation--inhibitory, more focal effect
• High Frequency Stimulation--facilitatory, multiple, spread out,
global “dendritic, axonal effect”.
When higher frequency rTMS is applied, a longer lasting effect can be
induced which is thought to result from a long term potentiation (LTP),
or depression (LTD) at the neuronal level.
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What Could TMS Treat?
• I. Psychiatry: Depression (FDA approval, Oct 2008), treatment
refractory cases, co-morbid, Panic DO, OCD, PTSD, Addiction
(pathologic gambling), food, other substances cocaine, opiates,
nicotine, schizoaffective disorder.
• II. Chronic neuropathic pains, phantom pain, fibromyalgia,
Migraine headaches, Tourette's, tinnitus, painful dystonia.
• III. Neurology: Rehabilitation- after stroke , recovery-Aphasia,
Neglect, Brain Injury, Seizures
Transcranial Magnetic Stimulation
• For MDD patients who have not adequately benefited from prior
medication treatment attempts
• New treatment recently cleared by FDA
– Has been studied by researchers for 20+ years
• Works by using MRI-strength magnetic field pulses
• Activates nerve cells in the brain, causing them to normalize
neurotransmitter function
• Non-systemic and non-invasive
– Does not circulate in the blood throughout the body
– Does not involve surgery
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Transcranial Magnetic Stimulation
• In an open-label trial (most like real world clinical practice),
– 1 in 2 had a significant improvement in symptoms
– 1 in 3 had complete symptom resolution
• Patients also experienced significant improvement in anxiety,
appetite changes, aches and pains, and lack of energy
associated with depression
• Over 10,000 procedures performed in clinical trials
• No systemic side effects such as weight gain, sexual
dysfunction, nausea, dry mouth, and sedation
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NeuroStar TMS Therapy
Positive Value Proposition
• Significant chance of improvement (1 in 2)
– Despite not having adequately benefited from previous
treatment attempts
• No systemic side effects, such as weight gain and
sexual dysfunction
• Non-invasive, no anesthesia, no sedation
• Favorable benefit/risk ratio compared to alternatives
• Associated with less hospitalizations, doctor visits,
drugs, etc.
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FAQs—Clinical
•
What are the chances it will work?
– In open-label trial (most like real-world), 1 in 2 patients had significant
improvement & 1 in 3 had complete symptom resolution
•
How long will it take to feel better?
– May feel some improvement in 2 weeks, but most improvement will take 46 weeks
•
How long will the effect last?
– In a 6-month follow-up study, patients received a single medication as
maintenance treatment
– Approximately 1/2 had symptom recurrence and required TMS re-treatment
– Through the maintenance medication and the TMS re-treatment, less than
10% of patients relapsed
•
What are the side effects?
– Scalp pain or discomfort and headache
– Decreased significantly after the 1st week of treatment
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FAQs—Financial (cont.)
• How much does it cost?
– Recommend speaking about cost for acute course, not per
treatment
• Some will require more treatments, others less
– Put it in context with the cost of other treatments
• Acute course of ECT is ~$18,000
• Acute course of a branded drug combination is ~$2,000
– Provides good value for the money
• Significant chance of improvement (1 in 2)
• No systemic side effects
• Non-invasive, no anesthesia, no sedation
• Favorable benefit/risk ratio compared to alternatives
• Associated with less hospitalizations, doctor visits, drugs, etc.
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Indication Statement
• NeuroStar TMS Therapy® is indicated for the treatment of Major
Depressive Disorder in adult patients who have failed to
achieve satisfactory improvement from one prior
antidepressant medication at or above the minimal effective
dose and duration in the current episode
54-00008-000 Revision A
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Fair Balance Statements
• NeuroStar TMS Therapy is contraindicated in patients with
implanted metallic devices or non-removable metallic objects in
or around the head
• As with any antidepressant treatment, patients should be
monitored for symptoms of worsening depression
• NeuroStar TMS Therapy has not been studied in patients who
have not received prior antidepressant treatment
• Efficacy has not been established in patients who have failed to
receive benefit from two or more prior antidepressant
treatments at minimal effective dose and duration in the current
episode
• The most common adverse event related to treatment was
scalp pain or discomfort
54-00008-000 Revision A
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New APA Guidelines
and CPT Coding
•
APA GUIDELINES
•
Transcranial magnetic stimulation is now listed in the American Psychiatric
Association’s 2010 “Practice Guideline for the Treatment of Patients with Major
Depressive Disorder”
•
It is listed as an acute phase treatment option for patients who do not respond
adequately to pharmacotherapy.
•
This recent guideline states; “Acute phase treatment may include
pharmacotherapy, depression-focused psychotherapy, the combination of
medications and psychotherapy, or other somatic therapies such as
electroconvulsive therapy (ECT), transcranial magnetic stimulation (TMS), or
light therapy.” (APA Guidelines 2010; Pg 46).
•
CPT CODING
•
Effective January 01, 2011, the American Medical Association has elevated the
current codes to Category I CPT codes.
•
The new codes are published as 90867 for a treatment planning session, and
90868 for treatment delivery and management per session.
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