Into the brain through the nostrils
Pioneering operation at Anuradhapura Hospital
There is purposeful concentration, while soft and soothing music plays in the background, as different teams of doctors and nurses, scrub up and move around Operating Theatre ( OT) C of the Anuradhapura Teaching Hospital.
On the operating table is a pretty middle-aged woman, but something seems unusual with her face – it seems unduly large, with the nose being pronounced.
While Consultant Anaesthetist Dr. Ayesha Abeyratne and her team are preparing the patient for surgery, two Consultants from different specialties are studying the Magnetic Resonance Imaging pictures. They are Consultant Ear, Nose and Throat (ENT) Surgeon, Dr. Daminda Dumingoarachchi who is also a Head and Neck Surgeon and Consultant Neurosurgeon, Dr. Stravinsky Perera. Although not present in the OT that day, Consultant ENT Surgeon Dr. Upul Abeysundara is also very much a part of this pioneering work in Sri Lanka.
It is a Monday morning and we too are in OT clothes and masks privy to viewing an operation not done anywhere else in the state sector, except the Anuradhapura Hospital.
Accessing the patient’s brain through the nostrils is what the ENT and Neuro Teams will do in one of many trailblazing procedures, while the Anaesthetic Team will ensure that her vitals are stable and the able theatre nursing staff will play their part.
Image- guided ( navigation- assisted) endoscopic trans-nasal trans-sphenoidal pituitary surgery is what we are about to view being performed in the country only since October this year. For, the 38-yearold patient lying inert on the operating table has a tumour just above her pituitary gland, between the optic nerves and the carotid arteries, making it a difficult operation- site to access. ( The pea- size pituitary gland is dubbed the ‘ master gland’ as it produces many hormones for the whole body, while also stimulating other glands to produce other hormones.)
Dr. Dumingoarachchi points out that the ENT navigator which the Anuradhapura Hospital was provided with recently, is like the GPS system of the brain which shows this vital organ’s architecture.
Dr. Perera explains that the patient has acromegaly, the abnormal production of growth hormones from the pituitary, causing a large nose and big hands etc. This is while it also causes an abnormal reduction in other hormones, affecting the functioning of the whole body. The enlarged pituitary is also compressing the main artery of the brain. A major issue is that the patient’s vision is being affected and if the tumour is not decompressed, she would go blind.
Matters also seem complicated as the patient had undergone ‘conventional’ brain surgery to remove an earlier tumour in the same area in 2009 in another hospital, but some parts had been left behind because it was complex surgery and the slightest slip of the scalpel could cause serious harm.
We watch in fascination as the surgical teams discuss how the tumour has grown around the right carotid artery making it a challenging procedure and is pressing down (compressing) on the brain.
This pituitary macroadenoma with acute intra- tumoural haemorrhage (bleeding) is “big” -- 5X3.8X3.5cms, says Dr. Perera, adding that laterally, the lesion extends to the right cavernous sinus encircling almost the full circumference of the cavernous part of the right carotid artery. The left carotid artery is spared.
Super-imposing the patient’s Computed Tomography (CT) scan with images of the real anatomy, the ‘ registration’ takes place for this ‘ re- do’ surgery, as he explains that the anatomy is distorted after her previous surgery done seven years ago.
In the freezing OT, we don’t feel the time passing as both the Neurosurgeon and the ENT Surgeon attend to their tasks, two pairs of hands working in tandem, not looking down at the patient but up at the two screens, while navigating the pathways through the nostrils to the brain.
Usually, such a large tumour above the pituitary gland will entail open-skull surgery, with the brain having to be retracted (drawn away from the site of the operation) to gain access to the tumour, we learn. While the dangers of such surgery are numerous, the patient also has to spend a long time in the Intensive Care Unit (ICU) in the recovery phase.
With the frontiers of medicine pushed b a ck more and more, D r. Dumingoarachchi says that now skullbase structures can be approached through the nose, ear and throat. “Such surgery involves dealing with pathologies located on the under-surface of the brain, with Neurosurgeons and ENT Surgeons together accessing the skull-base more easily through the nose, ear and throat.”
Pointing out that these trans-nasal and trans- labyrinthine approaches to the skull-base will help bring down the rate of revision neurosurgeries and cut down the time that the patient will have to spend in the ICU post-operatively, he adds
Anterior skull-base surgeries -Endoscopic anterior skull-base surgeries, starting with pituitary surgeries using the endoscopic trans-sphenoidal approach for the first time in Sri Lanka. The latest addition, in October this year, is image-guidance (navigation). The other procedures include cranio-pharyngioma, olfactory neuroblastoma, cerebrospinal fluid leak repairs, para-nasal sinus cancer resections and odontoid (cervical spine) decompression.
The advantages of this approach include a better field of view and ease of doing revision surgery if required, while leaving no external scars.
Nasal polyposis is also now being managed by image-guided powered full house functional endoscopic sinus surgeries, resulting in the reduction of the recurrence rate. This also cuts down revision surgeries.
Lateral skull- base surgeries – Throughmicroscopic lateral skullbase surgery, trans- labyrinthine acoustic neuromas have been removed. With direct access to these eighth- nerve tumours, no brain retraction has been necessitated, resulting in less post-operative morbidity. The whole tumour can be removed while preserving the seventh cranial nerve, as the hospital has also been given intra- operative cranial nerve monitoring facilities. Paying tribute to Dr. Palitha Mahipala, Director-General of Health Services, for making the navigator available to them, Dr. Dumingoarachchi also expresses appreciation to the Deputy DirectorGeneral ( DDG) of the Biomedical Division, Muditha Jayathilake, Biomedical Engineers Apsara and Kumuduni and DDG Dr. Lakshmi Somatunga for all their support.