Motorisation drives transcranial magnetic stimulation ( TMS ) treatment
CONTROL & AUTOMATION ALTERNATIVE MEDICAL TREATMENTS
EMS
Motorisation drives transcranial magnetic stimulation ( TMS ) treatment
Around one billion people are currently suffering from a mental health disorder , according to statistics from the World Health Organisation . Many patients are prescribed medication or counselling sessions to treat their condition , but not all patients find relief . Increasingly , alternative treatments such as transcranial magnetic stimulation ( TMS ) are being researched for such cases . Here , Dave Walsha , sales manager at DC motor supplier EMS , explores TMS and its underlying technology .
Rates of ‘ common ’ mental health disorders such as depression and anxiety rose by more than 25 per cent in 2020 , as the Covid-19 pandemic hit . In the UK , the presence of moderate to severe depressive symptoms in adults increased from ten per cent prepandemic to 19 per cent by June 2020 .
Common treatments for mental health conditions include medication , as well as therapy and counselling services . But not all patients find the relief they ’ re seeking in traditional treatments , and as such , more novel methods are being researched to help those with mental health conditions get the care they need .
One example of such a treatment is TMS . During treatment , the patient sits on a chair and a treatment coil is applied to their head . A TMS machine passes an electric current through the magnetic coil to generate a magnetic field , typically around two Tesla — a similar strength to an MRI scanner . This magnetic field is used to either stimulate or inhibit neurons in the cerebral cortex , the outer layer of the brain .
Exact locations and frequencies used for treatment vary depending on the condition being treated . When used for depression , the coil is placed over areas in the brain responsible for emotional control . For patients diagnosed with depression , these areas are often ‘ underactive ’ — by stimulating the neurons , this part of the brain can be reactivated , alleviating the negative symptoms experienced by the patient .
Repetitive TMS treatment can influence brain function , resulting in positive effects lasting
Motorisation is essential in many medical technologies , and TMS is no exception .
long after the treatment has finished . In fact , some studies of patients with depression have reported the clinical benefits of TMS are still present months after completing a course .
ENSURING PRECISE TREATMENT Crucial to the success of TMS treatment is the precision of the coil positioning . A course of TMS treatment typically comprises of one session daily , over a period of four to six weeks . Repetition is key in achieving the best possible patient outcome , but in order to do this , the machine must be able to accurately position itself each time .
Such accurate positioning is difficult to achieve manually . As a result , robotic arms have been developed to precisely position the coil , based on previous scans and measurements of the patient ’ s head . An optical monitoring system can be used to detect any head movements made throughout the treatment and allow the TMS machine to compensate accordingly .
POWERED BY MOTORS Motors used within these robotic arms must meet stringent requirements . For those motors closest to the coil , high electromagnetic compatibility ( EMC ) immunity is required . This is due to the strength of the magnetic field emitted , and to minimise any interference caused by the equipment .
A high starting torque is desirable for the machine to adjust quickly to sudden head movements . With the repeated nature of TMS treatments , it ’ s likely that the machine will be running for extended periods every day . As a result , the motors must also be able to work reliably , and without overheating or any loss of precision .
To achieve this , gearheads with a reduced backlash should be chosen , with encoders to guarantee precise positioning . A variety of small brushless DC motors can provide the high levels of torque required in the arm for it to adjust quickly , while still being compact enough to allow the machine to fit comfortably within a treatment room and move around the patient .
Finding micromotors capable of meeting such requirements while being compliant to medical regulations can be a challenge . FAULHABER motors , supplied in the UK and Ireland by EMS , have already been trialled and successfully implemented in a variety of medical applications , including TMS machines .
Motorisation is essential in many medical technologies , and TMS is no exception . Delivering treatments with high levels of precision time and time again is made possible with robotics . As the medical field continues to make advancements and explore other treatments , there ’ s no doubt that motors will continue to play a powerful and significant role .
For further information , please visit www . ems-limited . co . uk
42 PECM Issue 63