This information is of a general nature only. Please consult your doctor for specific advice concerning your condition.

What is Stereotactic Radiosurgery?

Radiosurgery is the use of sophisticated technology to identify a target (usually a brain tumour) and apply a 3 dimensional dose of radiation precisely to that target (within an accuracy of around 1 mm). It is an alternative to standard open surgery in some patients.

Radiosurgery involves collaborative planning by the neurosurgeon and radiation oncologist to design a treatment that will be accurately shaped to the tumour with a rapid fall off of dose nearby so that other critical structures are spared.

Radiosurgery planning

If the treatment uses radiation and not a scalpel, why is it called radiosurgery?

There are 3 reasons why it is called radiosurgery –

Firstly, there is an emphasis on exactly targeting a tumour and avoiding injury to any surrounding structures, similar to traditional open surgery.

Secondly, radiosurgery is usually a single dose, one-off treatment – again, similar to surgery.

The third reason is historical. Radiosurgery originated from a neurosurgeon, who conceived of a method of doing neurosurgery where the X-ray replaced the scalpel as a form of knife.

What conditions are suitable for radiosurgery treatment?

The most commonly treated tumours are secondary brain tumours (also known as metastases or mets), acoustic neuromas, meningiomas, and pituitary adenomas. There are a couple of non-tumour conditions which are also commonly treated called arteriovenous malformations (AVMs) and trigeminal neuralgia.

Other less common reasons for treatment include gliomas, craniopharyngioma, glomus tumours, cavernous malformations, chordomas and chondrosarcomas, tremor and epilepsy.

Radiosurgery is not suitable for all patients, so it is best to visit a team that has both neurosurgery and radiation oncology expertise.

What are the common names of radiosurgery systems?

Names such as Cyberknife, Gamma Knife and Novalis refer to systems specifically developed for radiosurgery use, but other units use Varian or other equipment.

A/Prof Jonker has previously used the Novalis Tx at the Lifehouse at RPA, and Gamma Knife at Macquarie University Hospital. He now uses the next generation intracranial radiosurgery device called the Zap-X, at St Vincent’s in Darlinghurst.

Zap-X Gyroscopic Radiosurgery platform

Do patients require an anaesthetic or admission to hospital?

No, patients receive their treatment whilst awake – and can return home the same day.

Is there any pain?

No – the X-rays are undetectable, you can’t see, hear or feel them!

What can I expect after the treatment?

It is common to feel a mild headache or some fatigue for a few days afterward. Usually, no special medications are required. Many patients will return to work the day following treatment. Most patient’s don’t lose any hair with this treatment, but occasionally patients will lose a very small amount of hair.

What follow-up is recommended?

Follow-up appointments will be made depending on the individual diagnosis. Radiosurgery generally controls tumours rather than making them disappear and so most patients are followed up long term.

Do patients always have their treatment in a single session?

There is an alternative to radiosurgery called fractionated stereotactic radiotherapy. It differs only in that the same precise technology delivers the treatment to the tumour using smaller individual doses over multiple days.

Why would a patient have their tumour treated over multiple days when it might be more appealing to get it over and done with in a single session?

Certain tumours have important nerves intimately associated with them- or even within the tumour. In these cases it may not be desirable to give the high single dose of radiation to the tumour since a portion of the nerve may receive the high dose intended for the tumour, with potential for complications. This can be particularly relevant for tumours around the hearing (cochlear) nerve and seeing (optic) nerve.

I have heard about frameless radiosurgery, what is this?

Traditionally radiosurgery has required the application of a head frame to achieve the precise positioning of the patient (and their tumour) for their treatment.

Most of the modern radiosurgery devices including the Zap-X have methods of achieving similar accuracy in positioning the patient using image guidance systems on the radiosurgery machine. A mask is used in these patients, though it is the image guidance system and not the mask itself that ensures accuracy down to the last millimetre.

What complications can occur?

This is always best discussed in the context of the patient’s individual condition.