A diagnosis of brain tumour evokes emotions of fear or even despair in patients and their loved ones. Many dread permanent disability or even early death, despite treatment. As the brain is one of the most critical organs in the body, any impact on it is generally considered serious.
Interview: Dr. Harisha P N, Senior Consultant, Neurosurgery, Manipal Hospital Yeshwanthpur.
Are all brain tumours cancerous?
No, many are benign and potentially curable by neurosurgery (and sometimes with other modalities). Examples of such tumours include meningioma (tumours in outer three layers of brain tissues), pituitary adenoma (tumours of the pituitary gland), schwannoma (tumours on peripheral nerves), and craniopharyngioma (tumours of the central nervous system).
Is surgery for brain tumours safe?
Safety in surgery has improved vastly due to technological advances—detailed studies of micro neurosurgical anatomy, improved microsurgical instruments and accessories, better understanding of functions in different areas of the brain, and techniques to monitor and preserve them during surgery.
Surgeries for brain tumour removal are usually performed with an operating microscope (or sometimes with an endoscope/exoscope), which provides excellent visualisation with a combination of magnification and brilliant illumination of the area of operation.
What are some recent advances that have contributed to increased safety of neurosurgical procedures?
Some of them are:
Neuronavigation: This is akin to using a GPS while operating on on the brain. Operations on the brain can involve exploring some deep and delicate areas through very narrow corridors. Navigation helps orient the surgeon through various important anatomical structures by showing the exact area of surgery in a preoperative MRI or CT scan “map”.
Intraoperative imaging: High-resolution ultrasound scans and tumour fluorescence performed through dyes depicts the amount of tumour removed at different stages of the operation and discovers residual tumours.
Intraoperative neurophysiological monitoring: It helps identify and preserve delicate structures (e.g., cranial nerves, critical brain tracts) that are in and around the brain tumour.
What is awake brain surgery?
When the tumour is located close to critical areas of the brain (e.g., those controlling speech and language or hand/leg movements), the neurosurgeon is usually wary of trying to remove the tumour completely, as this might risk causing disability to the patient. However, by keeping the patient awake during surgery, these critical areas can be identified and monitored throughout the operation to confirm that the critical functions are fully intact. Advances in the practice of neuroanesthesia and the fact that the brain itself has a few pain receptors have facilitated awake brain surgery. The patient is made to sleep during some parts of the surgery, which are painful, but during the crucial phase of tumour removal, the person is fully awake and performing certain tasks (specific to the area of the brain at risk) to aid monitoring. This allows the surgeon to completely remove the tumour, despite it being located very close to critical brain areas.
