Stereocon 2019 highlights advances in high precision neurosurgery

November 15, 2019 0 By FM

The 16th annual conference of Indian Society of Stereotactic and Functional Neurosurgery (ISSFN) – Stereocon2019 – brought to focus the latest advances in the field of stereotactic and functional neurosurgery, including radiosurgery.

The three-day conference, which was organised by the Cochin Neurological Society under the aegis of ISFN, was held in Kochi from 19th to 21st September 2019.

“The conference focuses on what you call stereotactic surgery and functional neurosurgery,” explains Dr. Dilip Panickar, Senior Consultant in Neurosurgery, Aster Medcity, Kochi and the organising chairman of Stereocon 2019.

Stereotactic surgery deals with high precision neurosurgery where mathematical principles and accurate targeting are used to arrive at the destination in a very precise and controlled way. 

Functional neurosurgery refers to an extension of stereotactic neurosurgery, which essentially serves to improve function, or deal with illnesses that affect the functioning of the human body or the nervous system. Classic examples are Parkinson’s disease and epilepsy, he adds.

Advances in neuromodulation techniques like deep brain stimulation (DBS) are speeding the growth of functional neurosurgery, making it one of the most rapidly expanding neurosurgical fields.

Modulation of neural activity of the central, peripheral or autonomic system is achieved by delivering a low-voltage electrical stimulation or a pharmaceutical agent directly onto the target area by means of an implanted medical device. 

DBS uses a surgically implanted medical device, similar to a cardiac pacemaker, to deliver mild electrical pulses to precisely targeted areas of the brain. 

DBS is indicated for various conditions ranging from movement disorders to psychiatric disorders, to persistent vegetative state. 

DBS may also alleviate symptoms in treatment-resistant clinical depression, and for intractable obsessive-compulsive disorder (OCD) once the patient cannot be benefitted by medical or other therapies, noted Dr. Paresh K. Doshi, Director of Neurosurgery, Jaslok Hospital, Mumbai. 

One of the key challenges in the use of functional neuromodulation techniques like DBS is a lack of awareness and reluctance among neurologists to refer patients for such surgery, averred Dr Sandeep Vaishya, Director of Neuro & Spine Surgery at Fortis Hospital, Vasant Kunj..

Studies have confirmed that nucleus accumbens stimulation for OCD may help in severe cases 

Half of today’s neurologists are neither aware of, nor trained in, DBS. Parkinson’s is a chronic, progressive disease. Each patient would have been to at least 3-4 neurologists in the last 7-8 years. Once they start getting worse, they might think the neurologist is not good enough and move to another. Even if one of neurologists tells them not to go for the surgery, the patients turn reluctant.

Nevertheless, one in ten neurologists recommend surgery. 

“There is lack of awareness, whether wilful or not, it is very difficult to say. It remains a challenge not only in India but also in many other countries.” he said. 

Neuromodulation for pain

Another area for application of neuromodulation may be in pain management where conservative options are rendered ineffective.

“Pain management is often an under-diagnosed, under treated and neglected aspect of a disease,” says Dr. Preethi P Doshi, Pain Management specialist and Consultant at Bhatia Hospital, Mumbai.

There are a variety of targets for providing neurostimulation, right from non-invasive to invasive, in the form of Repetitive Transcranial Magnetic Stimulation (rTMS), DBS, motor cortex stimulation, spinal cord stimulation, and some completely non-invasive techniques like Transcutaneous Electrical Nerve Stimulation (TENS).

Neuromodulation has three components: leads, an implantable pulse generator and a computerised patient/physician controller device which helps titrate the pain relief according to the requirement.

Spinal cord stimulation (SCS) for the treatment of pain involves delivery of electricity to the nerves in order to change their activity.

SCS involves a trial phase, and only if the patient responds well to the trial is he moved to the regular routine. 

“In the theatre, the patient is awake for the trial phase because we do an intraoperative stimulation by introduction of a lead which goes into the dorsal epidural space under fluoroscopic guidance. The patient experiences the system for 3-7 days and this is a very important part, where the pain and its side-effects are understood. If it is a complex progressive pain, we would choose multiple contact points so that we have more freedom of programming to give the best possible relief to the patients,” explains Dr Preethi.

Peripheral nerve stimulation (PNS) is another approach to treat chronic pain. It involves surgery that places a small electrical device (a wire-like electrode) next to one of the peripheral nerves.

PNS is used when a patient has very localised neuropathic pain. The physician can introduce a subcutaneous lead which can result in the control of the pain. This is especially useful for truncal, axial, back and neck pain, where conventional methods are not helpful.

The conference also discussed surgical management of dystonia and neurosurgical procedures for spasticity. 

Operative approaches in epilepsy surgery, epilepsy evaluation techniques — including stereoelectroencephalography (stereo-EEG) — and the evolution and future of surgery were also discussed.

Using Stereo-EEG procedure, electrodes are placed directly in the brain to identify where epileptic seizures start. Surgeons can then remove the part of the brain that is causing the seizures.

Genetic engineering promise 

Research in tissue engineering, genetics and nanotechnology holds new promise with respect to neuromodulation devices.

“People are proceeding in that direction so fast that in the next 10 years, all this hardware will go out and more of genetically engineered, genetically deliverable material will come up,” says Dr. Krishnakumar K, Professor at Department of Neurosurgery, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum.

He also gave an update on research into newer techniques like a hybrid DBS device which may also be capable of delivering stem cells or neurotransmitter or a drug onto the target site.

The first day of the event included a pre-conference workshop on stereotactic radiosurgery at Aster Medcity and on functional neurosurgery at Amrita Institute. Around 100 participants convened at the event.