Difference Between dTMS and rTMS

Deep TMS and Repetitive TMS treatments are being used in cases of severe treatment-resistant depression. While the methods are similar, there are certain basic differences that dictate the results.

Brain stimulation therapies have been gaining increasing leverage as an alternative treatment for depression. They are usually preferred when first-line treatments like medication and psychotherapy fail to achieve the desired results.

Of these, Transcranial Magnetic Stimulation (TMS) has managed to achieve some breakthrough remissions and is one of the popular brain stimulation methods for treating depression and other mental health conditions.  In fact, there are two types of TMS clinical therapies offered by depression treatment centers – repetitive TMS (rTMS) and deep TMS (dTMS).

The rTMS was developed first and is considered the standard TMS treatment while the dTMS is basically an improvement over the rTMS technique. But, both these methods are primarily drug-free and non-invasive treatments that manage to normalize the neural activity in the brain. It is painless and do not require sedation – the patient can return to work immediately.

The basic TMS technique is simple – a large coil (similar to an MRI magnet) is used to transmit electromagnetic pulses to specific parts of the brain. The coil has to be carefully positioned based on the targeted brain cells (associated with mood) that have to be stimulated. This slowly changes the neural pathways so as to alleviate the symptoms of depression.

Both the methods have proved to be safe, effective and free of any physical or neurological side effects.

Let us understand the primary differences between these two types of TMS therapies:

Shape – rTMS uses a magnetic coil that is shaped like the figure 8 while dTMS is done using an H coil (H-1 usually but a new H-7 has been developed recently).

Pulse rate – In standard rTMS treatment, the electromagnetic field is repeatedly pulsed into the brain with increasing strength thus creating a stronger electromagnetic induction. In contrast, dTMS works on a continuous strength that maintains a steady electromagnetic pulse throughout the treatment.

Range – The rTMS coil manages to penetrate around 3cms into the skull. This allows it to stimulate the prefrontal cortex alone. On the other hand, dTMS treatment can safely penetrate up to 4cms. Therefore, it manages to reach deeper brain structures directly and can stimulate broader areas of the brain.

Duration – rTMS therapy has to be delivered for around 35 to 40 minutes to have the desired impact while dTMS sessions last for 20 minutes only.

Efficacy – Studies show that the response rate of rTMS (after six weeks - 30 sessions) is about 58% with about 37% of the patients achieving remission. In the same duration, around 75% of patients responded positively to the treatment and 51% managed to achieve remission.  The broader range of activation in dTMS is considered the reason for the superior response rate.

Therefore, a direct Transcranial Magnetic Stimulation near me is a more effective option for mental health conditions; of course only under the guidance of an appropriate healthcare professional.