Ketamine can make depersonalization/dissociation and have been used as a model for depersonalization in some studies. So, it makes state like the condition,- not curing it. Some with refractory depression can benefit from infusion with it. Never heard of any have had any benefits. Daniel Amen is charlatan who claims to be able to make diagnoses with the use of SPECT scans. SPECT scans are very old and have not be used in psychiatric research for more than 2.decades as it is not very precise. But, a charlatan can use it as a money machine.
I am waiting for the development of something called "Synchronized TMS". In reality is it developed and tested in depression in 3.trails. It is not approved to any condition but as a device for mental health wellbeing in the US. It works by adjusting and giving feed backs to brain accelerations that makes the diffrent brain waves- EEG.
It has 3.coils to the front, center and back of the brain making a small magnetic feedback to the oscillations deep in the brain. Depersonalization can be seen as abnormal state where the brain have to low oscillations (theta) and dysrhythmic -like you are on ketamine.
They take a qEEG of your brain to know the frequencies of the diffrent areas and feed it in a a computer connected to sTMS device so it can give feedback and reset the brain to more normal brain waves that is more synchronized.
I think they have 8-12.clinics in the US and California is optimal as their head quarter is there. A Eric Won is the head of it. It have never been tried but I find it to be the technology most promising for depersonalization.
They might also be interested in trying if it works in a refractory condition as depersonalization is.
A video with the device.
Synchronized TMS in anxiety and depression.
It have been sold to this company. Their site.
Brainwave Recording Locations