The FDA has approved a six-week TMS protocol for treating depression. However, a recent study at Stanford University, entitled Stanford Accelerated Intelligent Neuromodulation Therapy for Treatment-Resistant Depression (SAINT-TRD), demonstrated that when TMS was delivered in a more intensive schedule and accelerated pace, it provided remission from depression in 90% of patients in as little as 3 to 5 days. These results were published online April 7, 2020, in the American Journal of Psychiatry. A follow-up study published on October 29, 2021, in the American Journal of Psychiatry entitled Stanford Neuromodulation Therapy (SNT): A Double-Blind Randomized Controlled Trial confirmed these results and renamed the procedure from SAINT TMS to SNT TMS.
In the Stanford study, patients underwent ten sessions per day of 10-minute treatments, with 50-minute breaks between treatments. Each treatment was a modified version of “Theta Burst” TMS, requiring specialized equipment. After a day of therapy, one study participant’s mood score indicated she was no longer depressed, while it took up to five days for other participants. On average, three days of therapy were enough for participants to experience relief from depression. The follow-up study showed virtually identical results to the original study.
We treat patients using the same parameters used in the Stanford study. The only difference in our approach is that we use an effective office-based method of finding the treatment location, called direct brain mapping, rather than a combination of MRI and computer modeling, as was used in the original studies.
We have been treating patients using Accelerated TMS at Cambridge Biotherapies™, and our experience has made us optimistic that this new treatment approach represents a paradigm shift in TMS therapy. The area of the brain we target with TMS to treat depression is the left dorsolateral prefrontal cortex (LDLPFC). This area is relatively underactive in patients with depression, and when we re-activate this region using TMS, the symptoms of depression often remit.
There are two standard methods of locating the LDLPFC: the 5.5 cm rule and the F3 method.
Using the 5.5 cm rule, the clinician first places a paddle (referred to as a “coil”) that delivers single pulses of magnetic energy over the area of the patient’s head that roughly corresponds to the motor cortex, which is the part of the brain that controls all voluntary movement. By delivering individual pulses, the clinician isolates the location within the motor cortex that most reliably elicits activity from the contralateral (opposite) thumb. The treatment area is then marked 5.5 cm anterior to this spot.
The F3 method builds off the 10-20 system, used to locate sites for the placement of EEG (electroencephalography) leads. In the 10-20 system, the location referred to as F3 correlates to the LDLPFC. With the F3 method, three measurements of the patient’s head are taken, and then a computer program calculates corresponding measurements that allow the clinician to locate F3.
MRI and computer modeling together located the treatment areas in the Stanford study. On average, these areas were approximately 1 cm lateral to the F3 location. By finding the spot 1 cm lateral to F3 and using a coil that stimulates a large enough area, we can target the site that correlates to the location of all patients in the SNT studies whose treatment target areas were located using the combination of MRI and computer modeling.
Given that (1) our targeting method closely replicates the SNT method, and (2) we can deliver the same high-dose iTBS (intermittent theta burst) protocol that was used in the SNT studies, we have found that Accelerated TMS can offer results similar, if not identical to, SNT. To date, our years of expertise and experience supports this assertion.