Long story short, i am a long term patient of the brai2n clinic in Antwerp. Dirk De Ridder was my physician. I had done a TMS test which was negative so i was prescribed a neuronavigated TMS test. It is the same principle but the coil is placed by a robotic arm guided by your neuroimaging data. Thus, in order to know very precisely where my tinnitus activity is they made a fMRI so i have pretty images of my tinnitus.
Of course it is mostly the auditory cortex which is lighted up. They were able to tell me my main tinnitus frequency was 8300 hz. Audiological tests gave no reliable result.
In addition: some EEG images of my poor brain:
This one shows the connections between activated brain zones:
By the way, i have some news from the clinic: De Ridder Left for New Zealand. He keeps in touch with the clinic weekly via skype. One of his research colleagues, Sven Vanneste who has copublished many recent papers with him went to Dallas to work with Kilgard on VNS ! So all that is left is an ENT, Paul Van Den Heyning as director of the clinic. He was codirector with De Ridder. They are looking for other physicians to complete the staff.
They aren't satisfied with their pilot study on VNS. Initially, 7 of the 10 patients had good results but most reverted back to their previous states. Long terms wise, only two of them have a light amelioration. Shown by both the EEGs and the questionnaires. I was told that the tinnitus of the lab rats was recent and some of the human test patients had tinnitus as old as 8 years. Also the implantation wasn't complete: they had just an electrode on their vagus nerve but used an external stimulator which was used only in hospital for short sessions. Maybe with an implanted stimulator sending impulses all day long the results will be better.
I was also told about the electrode implantations. They are still perfecting this. Since overctive cortical zones stimulate each other, taming one zone with one electrode is efficient with a minority of cases. that's why they experiment with mutli electrode implants. Sometimes 3 or 4 electrodes on different cortical sites ! The problem is often the tinnitus is tamed at first but comes back after a while and they have to find new stimulation parameters. They told me they still need several years to perfect this. Some lucky patients have had a total suppression of their tinnitus with that but they are a tiny few.
Anyway an implantation of one electrode costs around 20 000 € ! I don't want to guess how much it would cost for mutli electrode implants.