In the realm of mental health treatment, innovative technologies continue to revolutionize traditional therapeutic approaches. One procedure that has gained widespread acceptance in treating psychiatric and neurological disorders is transcranial magnetic stimulation (TMS). TMS is a noninvasive treatment that uses magnetic stimulation to activate specific regions of the brain.

The two best-known procedures of TMS are repetitive transcranial stimulation (rTMS) and deep transcranial stimulation (deep TMS). One major difference between the two (which explains the “r” and “deep” prefixes) is that rTMS repeatedly pulses the targeted field at a shallow depth, while deep TMS delivers stimulation deeper and with a wider area of influence.

Similarities Between deep TMS and rTMS

Both deep TMS and rTMS are noninvasive treatments that use magnetic pulses to activate specific brain regions, helping to regulate mood and emotions by balancing neuronal circuits. The prevailing theory of depression suggests that an imbalance in neurotransmitters like serotonin, dopamine, or norepinephrine plays a critical role in mood regulation. TMS helps restore balance to these neurotransmitters, alleviating depression.

Both forms of TMS are safe and well-tolerated, with no significant physical or neurological side effects. They can also be used alongside medication without additional side effects. A 2019 study showed that combining TMS with an antidepressant had a higher response rate than medication alone. The study further demonstrated that, in treating major depression, deep TMS combined with medication had a 67% response rate, compared to 44% for rTMS with the same medication. While both are more effective than medication alone, deep TMS has a higher response and remission rate than rTMS.

Differences Between deep TMS and rTMS

A key difference between deep TMS and rTMS lies in their coil design and targeting approach. rTMS uses a figure-eight coil to target a focused area at a depth of 0.27 inches (0.7 cm), stimulating the dorsolateral prefrontal cortex (DPC), which is responsible for executive and cognitive functions such as working memory, attention control, and abstract reasoning. While effective in treating depression, rTMS’s limited reach into deeper brain regions may shorten the remission period for some patients. The shallow focus of rTMS may also limit its effectiveness in treating neurological disorders located deeper in the brain.

Deep TMS, by contrast, uses an H-coil design in a helmet that stimulates up to 1.25 inches (3.2 cm) into the brain. This allows for deeper and broader stimulation, reaching areas inaccessible to traditional rTMS.

Deeper Stimulation with deep TMS

Deep TMS offers the advantage of reaching deeper brain structures and modulating neural circuits involved in complex mental health conditions. Its H-coil design stimulates deeper prefrontal cortical areas that connect to subcortical networks. By targeting these deeper regions, deep TMS provides more comprehensive treatment for major depression, influencing areas like the anterior cingulate cortex and other limbic structures, which play key roles in emotion regulation and motivation.

Deep TMS’s ability to reach deeper brain regions also makes it effective in treating conditions such as obsessive-compulsive disorder (OCD) and post-traumatic stress disorder (PTSD). It also shows potential in treating neurological disorders like Alzheimer’s, Parkinson’s, Multiple sclerosis (MS), and neuropathic pain.

Broader Stimulation with deep TMS

Deep TMS’s broader stimulation can influence multiple neural circuits simultaneously, making it particularly effective for treatment-resistant depression. While rTMS focuses on a singular target during treatment, deep TMS can treat multiple neural sites in one session. This has significant implications for neurological disorders like Parkinson’s disease. For example, a recent study concluded that stimulating both the right and left frontal cortex simultaneously provided the best outcomes for patients with Parkinson’s.

Precision of Coil Placement

Deep TMS can target deeper brain regions with greater precision than rTMS. The smaller, more focused stimulation area of rTMS can lead to inconsistencies in treatment if the coil is not positioned correctly during each session. Studies have shown that misplacement of the rTMS coil by technicians can reduce the treatment effect by as much as 48%.

In contrast, deep TMS stimulates a broader area, ensuring that the target region is consistently treated with each session.

Side Effects

Both rTMS and deep TMS are associated with mild and short-lived side effects, such as headaches, scalp discomfort, lightheadedness, and facial muscle tingling. One side effect unique to deep TMS is temporary jaw pain, reported by 10% of patients. Although there is a slightly higher risk of seizures with deep TMS due to its broader reach, the seizure rate is comparable to that of antidepressant medications. Unlike medications, deep TMS is not associated with side effects such as nausea, weight gain, loss of sexual desire, or fatigue.

Conclusion

TMS is a proven treatment for major depressive disorder (MDD), especially for those with treatment-resistant depression. Deep TMS, however, goes beyond traditional rTMS by accessing deeper cortical and limbic areas critical for reversing depression. Moreover, the broader reach of deep TMS opens possibilities for treating a wide range of neurological disorders, such as Parkinson’s, Alzheimer’s, MS, and neuropathic pain. While rTMS has its strengths, particularly for more superficial brain regions, deep TMS offers a wider scope of treatment possibilities, both psychiatric and neurological.

To find out if deepTMS may be right for you, call ReNu and schedule a free consultation.