Posted by jrbecker on June 19, 2004, at 18:16:04
In reply to Re: rTMS'rs out there ??? jr becker, posted by Pfinstegg on June 18, 2004, at 21:19:11
I will be sure to give you guys a full report in a couple of weeks (3 weeks in).
Pfinstegg, it's too bad you were disqualified from the study b/c of your left-handedness. I don't even recall being asked the question about dominant hand usage when I was originally screened.
Scott, I would echo Pfinstegg's statement about rTMS being less effective than ECT. However, in one recent study rTMS was found to be effective in remitting 55% of patients vs. 64% in bilateral ECT. Secondly, they are still figuring out the optimal ways to enhance efficacy for rTMS. For this study, Neuronetics has manufactured brand new high-tech models to be used. And the procedural protocols such as angle of stimulation, location, frequency, treatment duration, etc; are becoming more and more fine-tuned to leverage the treatment outcome. For instance, this study is the first to increase the stimulation to 120% of one's motor threshold. In the past, 110% has been the typical limit. Lastly, in terms of comparing ECT to rTMS once again, it's apparent that ECT's advantage comes from its ability to cause a grand-mal seizure in the brain, thus affecting the deeper regions of the brain (e.g., the limbic system). rTMS, like Pfinstegg mentioned, is much more localized in its stimulation of the prefrontal cortex (and probably parts close to it like the anterior cingulate). I believe that this is in fact the benefit of rTMS over ECT for some individuals. It's been shown that individuals suffering from bipolar disorder [and probably atypical depression] show dysfunction in the PFC region in addition to deeper brain regions. Some studies have also shown that melancholic unipolars display PFC deficits, but probably to a much lesser degree. Anyways, this is why I hold a torch for the potential of rTMS. Newer ECT methods, such as nondominant right unilateral ECT or rapidpulse right unilateral ECT might also be beneficial for the same above reasons and have been reported to cause less side effects (e.g., ST memory loss) than other forms of ECT.
As for when it might be approved, the researchers and I have talked about this quite a bit. Because of the recent VNS approval it looks quite optimistic, especially since their data did not look as effective as past rTMS studies have. A potential obstacle to a speedy rTMS approval might be some political maneuvering from clinicians in the ECT camp who perhaps [falsely] see rTMS as a potential threat to it.Neuronetics, the maker of the newest magnetic stimulation devices, is the major backer of the current national rTMS study. The study includes 16 sites, and will be including 287 subjects in all. At this point, it seems that most of the sites have been very slow in being able to enroll subjects, mostly because the eligibility criteria is so stringent. Because of this, I have tended to be more conservative in predicting a possible approval by the FDA any time soon. If I had to guess, I would say 2-3 years.
But I could be wrong on this. For one thing, it seems that a few of the sites are finally beginning to enroll more and more subjects. Secondly, I've been told that the company might be approaching the FDA midway through the trial if the preliminary data analysis looks good. So perhaps an approval by the end of 2005 isn't completely out of the question. I will keep my ear to the ground on this one for you all and hope to give some frequent updates.
JRB
poster:jrbecker
thread:357593
URL: http://www.dr-bob.org/babble/20040614/msgs/358161.html