Page 26 - Delaware Medical Journal - March 2016

Deep Transcranial Magnetic Stimulation:
A Promising Drug-Free Treatment Modality in the Treatment of Chronic Low Back Pain
Erin Yates, BSc and Ganesh Balu, MD
Deep Transcranial Magnetic Stimulation (dTMS) is the next generation of technology used to treat Major Depressive Disorder (MDD). dTMS has been proven to be a safe and effective treatment modality for MDD and may have secondary benefits in patients with chronic low back pain by reducing pain related morbidity. We are presenting two case studies with MDD and chronic low back pain to demonstrate the effectiveness of both the antidepressant and analgesic effects of dTMS.
Background: Transcranial Magnetic Stimulation (rTMS) utilizes MRI-strength magnetic pulses outside the cranium to stimulate the brain to a depth of approximately 1 cm. The technique was approved by the US Food and Drug Administration (FDA) for the treatment of Major Depressive Disorder (MDD) in 2008. In 2013 the Brainsway Deep Transcranial
Magnetic Stimulation (dTMS) device, which has the potential for cranial penetration up to 5 cm received FDA clearance
for pharmacotherapy and psychotherapy resistant MDD. The mechanism of action of dTMS in MDD is not completely understood. However, its clinical efficacy is proven.1 The effect of dTMS on the brain has been studied since 1985 in
clinical trials and has been demonstrated as an effective treatment modality for refractory depressive symptoms. The mechanism of action of dTMS is thought to be mediated by increased connectivity between the dorsolateral prefrontal cortex (DLPFC) and the thalamus and reduced subgenual cingulate to caudate connectivity. These brain areas are believed to be responsible for modulating mood. Chronic pain is often accompanied by MDD. Specifically, chronic low back pain is highly prevalent and accompanied by significant disability.2 Low back pain is defined as chronic when the pain is continuous for more than three months.3 The current chronic pain treatment algorithm includes judicious use of non pharmacological interventions like physical therapy, chiropractic adjustments, therapeutic massage, or acupuncture combined with pharmacological interventions that utilize non-narcotic or narcotic oral medications, spinal/paraspinal injections and,
in selected cases, surgery. In patients who fail this extensive algorithm for chronic pain management and are left with significant morbidity and disability, coincident MDD frequently becomes refractory to therapy. Two illustrative examples
of chronic low back pain patients with medically refractory MDD treated successfully using dTMS are presented here to discuss the potential therapeutic benefits for both MDD and chronic low back pain in this setting.
Keywords: Drug-free, non-narcotic, no side effects, decrease in medications, cost effective chronic pain treatment
CASE STUDIES
Case Study 1
A 63-year old male patient with dual diagnosis of chronic MDD of 10-year duration and chronic low back pain of 15-year duration presented to us for management. He was on 100 mg of sertraline
q daily for more than a year and had previously failed trials of disc herniation and accompanying degenerative changes without any evidence of surgically correctable root compression or other relevant pathology. The patient had no spinal surgical intervention and his pain was partially managed with 100 mg daily dosing of Tramadol. The patient was offered a course of dTMS therapy as an outpatient option. The patient participated in 26 dTMS sessions

remaining six sessions over a three week period). Sessions were
20 minutes in duration and consisted of a two-second period of
18 Hz rapid magnetic pulses followed by 20-seconds of down time and then back to a two-second burst of pulses. Before undergoing dTMS his Visual Analog Scale (VAS) pain rating was 8/10. Upon completion of dTMS the patient has an average VAS of 5/10 and his MDD went into remission with Becks Depression Inventory (BDI) and PHQ9 scores of 0 (Figure 1). Four months post treatment the patient continues to be in remission from depressive symptoms and has titrated off his antidepressants while still experiencing reduced pain. The patient suffered no adverse events throughout and remained treatment compliant for the seven weeks of dTMS therapy.
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Del Med J | March 2016 | Vol. 88 | No. 3
Abstract