New waves in psychiatric treatment

Source: The Hitavada      Date: 23 Jul 2018 12:34:06


 

 

By Gargi Gupta

Magnetic waves to treat depression? The idea may sound newfangled, but that’s exactly what psychiatrists around the world have turned to – repetitive Transcranial Magnetic Stimulation (rTMS), as the technology is called, in their fight against this mental illness, which statistics say affects around 5 per cent of the population of India. And they report encouraging results. Dr Meena Kasargod, consultant psychiatrist at the Columbia Asia Referral Hospital, Yeshwanthpur (Bengaluru), has been using rTMS for the past six years. “Magnetic impulses are made to penetrate 4 mm into the brain to target the left prefrontal cortex, which is known to function abnormally in depression,” she explains. rTMS, Kasargod says, is “thought to work exactly like medicines, causing a redistribution of chemicals inside the brain.” These are serotonin, norepinephrine and dopamine, which regulate mood, and are imbalanced during depression. Patients are given 20 half-hour sessions a month, and report feeling 80 per cent better and lead a better quality of life.

rTMS is among a range of fast emerging technologies, called ‘neuromodulation’, being used to treat psychiatric illnesses in hospitals such as AIIMS, NIMHANS, and PGI-Chandigarh, over the past decade or so. Some of these, like rTMS, are non-invasive. Others like Deep Brain Stimulation, (DBS) require surgery. DBS, involves inserting an electrode, or LED inside the brain, which emits periodic electrical signals to stimulate affected parts of the brain. This is widely used in the treatment of Parkinson’s Disease and also Obsessive Compulsive Disorder (OCD). According to Dr Anurag Gupta, consultant neurosurgeon at the Fortis Flt Lt Rajan Dhall Hospital in Vasant Kunj, Delhi, “The brain’s limbic system controls behaviour and emotions, and any chemical disbalance, or a tumour or stroke that affects the limbic system can cause psychological disorders. When you target the limbic system, it can help to control OCD.” At Jaslok Hospital in Mumbai, Dr Paresh Doshi, director of the department of neurosurgery, has even used DBS to treat depression. “We have done surgeries on 14 patients of OCD and depression, including three from Australia and two from the US,” he says.The hospital will also shortly launch rTMS and Vegal Nerve Stimulation (VNS), another emergent neuromodulation technique, which has proved effective in the treatment of depression. In VNS, explains Doshi, an electrode, “like a pacemaker”, is inserted by surgical procedure near the collarbone to modulate serotonin levels. “It has a 60 per cent-70 per cent success rate,” he says. rTMS, on the other hand, has a 40 per cent50 per cent success rate and may require repeated sittings. Besides depression, rTMS has also been found effective in treating Anxiety Disorders, Attention Deficit Hyperactivity Disorder (ADHD), Tourette Syndrome (a disorder characterised by tics, or repetitive, involuntary movement), and Anorexia Nervosa. While they don’t obviate the need for medicines, rTMS causes them to be far more effective, leading to lower dosages, says Kasargod. Even surgical procedures such as DBS do not damage the brain unlike earlier surgeries, which caused lesions, says Gupta. “It does not ‘cure’, but gives symptomatic benefits and so helps quality of life to become better. In that sense, it has the same effect as medication, but without the side effects.” Agrees Dr Guruprasad Hosurkar, neurologist at Columbia Asia Hospital, “The complications with DBS are less. When it is switched off, the brain goes back to being what it was.

” But there are some pitfalls, the most important being the lack of regulation. There are high costs, for one.While rTMS costs around Rs 60,000 for the entire treatment, DBS is far more expensive at around Rs 10 lakh for the surgery. Two, in the US, the FDA approved rTMS only in 2008, but only in the treatment of depression. As for DBS, says Gupta, it has been certified for use by the USFDA for just three conditions – Parkinson’s, OCD and Dystonia (a movement disorder). In India, the regulatory mechanism for any developing technology such as neuromodulation is much more slack. According to Doshi, the Mental Health Act, 2017 allows psychiatric surgery to be performed, with the provision that it should be overseen by an ethics committee or a hospital review board.