2.Problems with rTMS
1) We do not know exact locations where the emotional overregulation done in the prefrontal cortex making the emotional numbing and suppressing the emotional system. In scan the right DLPFC, the right VLPFC, the anterior cingulate and the dorsomedial prefrontal and in some the right orbito frontal cortex. This are extremely many and very confusing locations. The right DLPFC is a standard location for depression done by almost all rTMS clinics and very few respond to this location if you have depersonalization disorder in its primary form. If it's secondary to depression the response rate it likely much higher. The fact is we don't know the core locations. The brains scans done dates back between 2000-2015. The size of the patients groups have been around 12 and most studies say that you have to and a patient group of at least 20 and a control group of the same size to reduce errors. Newer scannings are also needed as the technology have evolved. fMRI scanners have become much faster as the computers supporting them have more power. These scanners are for research only. You can not as a private person get a fMRI and those on the private market do likely not have enough computer power as those used in research-simply too costly. fMRI and the older and less effective PET and the very, very old SPECT are functional scanners and are looking a brain metabolism- over and under active areas in the brain to stimuli. In a recent evolution of brain imaging studies done in depersonalization they said that they excluded PET, SPECT and QEEG studies as worthless as they are old and very imprecise. So, why as a patient use money on "mental horoscopes of the brain" that QEEG, PET and Spect are. I can tell you for free that it is pointless.
Scanners like MRI, CT are structural scanners that looks at the structure of the physical brain, for injuries, stroke lessons or tumors. In most with depersonalization such a scaning will come out as normal.
You use a MRI scan not for diagnosis with rTMS but for location of areas. Because our brain structures are slightly different from person to person it can be very difficult to locate an area in the brain. You might risk not stimulating the correct area in the brain without neuronavigation from MRI. So, it has nothing to do with understanding the disorder a MRI is taken but location of areas in the individual brain.
To sum up. We don't known exactly location where the emotional regulation is done. The recent evaluation I referred to point towards the anterior cingulate and the dorsomedial prefrontal cortex.
Here is a brain scaning picture of emotional regulation in depersonalization from 2015 and on the picture there is and overactivity in the right VLPFC and the anterior cingulate and the dorsomedial prefrontal cortex. The problem is that these locations are much deep into the brain for a normal rTMS coil to stimulate. https://www.ncbi.nlm.nih.gov/core/lw/2.0/html/tileshop_pmc/tileshop_pmc_inline.html?title=Click%20on%20image%20to%20zoom&p=PMC3&id=4890597_fpsyg-07-00432-g0002.jpg
2) rTMS in Europe and the US are only approved for depression at the right or left DLPFC. These locations are easy to find without neuronavigation and easy to stimulate as they are on the frontal brain of cortex. There is no brain tissue above these areas. All rTMS it set up for the location and stimulation of the two locations only. In people with depression around 50% will respond at these locations and the rest will not. That is because in depression the emotional regulation likely comes from much deeper locations in the brain in many who don't respond. These people with depression can't get a treatment either with the equipment used in most places now. As there are some conflicting data about the locations in depersonalization we could say that it it likely that the anterior cingulate cortex and the dorsomedial prefrontal cortex plays a role along with right VLPFC. So, you want rTMS at these locations. But, most clinics can not locate these locations as they don't have neuronavigation. But, the coil they use is a normal butterfly 8.coil. It can stimulate 1.cm into the brain. If you look at the brain scan you can see that the activity of the right VLPFC is much deeper than 1.cm. You can likely stimulate 30% of the right VLPFC with a normal coil. The anterior cingulate and the dorsomedial prefrontal cortex can not be stimulated at all with a normal coil as they are too deep. There are coils developed that can stimulate these areas and they are used in research for depression, OCD and PTSD. They are not approved for clinical use in clinics yet. You have to work at approved research facility that have the right to use this equipment for research. A deep coil has just been approved in the US for OCD and that is for the stimulation of the anterior cingulate and the dorsomedial prefrontal cortex.
you can try the right VLPFC with the stimulation of 30% of it that a normal coil can do or you can wait until there are private providers that uses deep coil in Europe and that the French rTMS at the angular gyrus might also come up with some ideas for where the emotional regulation in done in the prefrontal cortex.