Gamma knife technology

A ground-breaking piece of technology that delivers non-invasive radiation treatment for brain conditions.

What is Gamma Knife technology?

The Leksell Gamma Knife is a ground-breaking piece of equipment used to treat brain tumours and certain brain conditions. It directs radiation beams to a specific point in the brain without the need to cut into the skin. Because it's non-invasive and so exact it can treat tumours previously considered inoperable due to the high risk of complications, such as those near in or near the brain stem and other deep-seated lesions.

Unlike conventional radiation therapy, its precision means healthy brain tissue shouldn't be affected by the radiation. It's accurate to within 0.5mm and one treatment is usually enough. This can reduce the overall dose of unwanted radiation by up to 100 times compared to other treatments. As side effects are minimal, people who've had Gamma Knife treatment can often go home the same day.

Conditions we can treat

Head based tumours, often these are benign tumours including:

Meningioma
Vestibular schwannoma (Acoustic neuroma)
Arteriovenous malformation (AVM)
Pituitary adenoma
Functional disorders such as Trigeminal neuralgia (severe facial pain) and epilepsy.

The gamma knife can also be used for movement disorders such as Parkinson's disease. malignant deposits from cancer elsewhere in the body and some vascular disorders related to brain tumours.

Worldwide, more than one million patients have been treated with Gamma Knife radiosurgery, of which 81% have been treated for malignant or benign tumours.

Gamma Knife radiosurgery vs convention surgery and cancer treatment

What are the benefits?

Treatment can usually be delivered in a single day
Rapid return to work
No surgical complications such as bleeding, infection or leakage of cerebrospinal-spinal fluid.

The Gamma Knife system was the first ever radiosurgery device and works by damaging the tumour cells so they can no longer grow. It has revolutionised the treatment of certain benign and malignant tumours in and around the brain, replacing the need for surgery in many cases.

Unlike conventional radiotherapy, radiosurgery is only directed at the abnormal tissue and so it spares the normal brain tissue nearby.

Gamma knife treatment set up still video.jpg

Why the Icon?

Although the Gamma Knife has now been in general use for over 30 years, technology has advanced tremendously during that time and the latest model reflects this. Because the state-of-the-art Icon delivers radiation with unbeaten precision and accuracy, it allows both patient and physician greater choice when planning scans and treatment. In order to deliver beams of radiation with submillimetre accuracy, the patient’s head must be held securely to avoid inaccuracy due to movement. The Icon offers more flexibility than earlier machines.

For earlier Gamma Knife models, a rigid frame had to be fixed to the patient’s head with four pins under local anaesthetic. The frame prevents head movement during treatment and allows precise delivery of radiation.

The Icon adds the option of using a standard radiotherapy mask to immobilise the patient, although the frame remains an option where the extra precision is necessary. The HCA UK London Gamma Knife Centre was the first Icon centre in London to use a radiotherapy mask.

“No patient or radiosurgery treatment is exactly the same as another. The Gamma Knife Icon offers freedom to adapt and optimise treatment planning.
”

Mr Cormac Gavin

Honorary Consultant Neurosurgeon, St Bartholomew’s NHS Hospital, London

How does Gamma Knife radiosurgery treatment work?

Gamma knife radiosurgery is not an actual 'knife', the technology uses Gamma rays that treats targets within the brain. Gamma knife works by putting 192 beams of radiation through the head, all converging at one point. The beams go through the brain doing very little damage until they get to the point where the lesion is. The accuracy of the gamma rays is better than half a millimetre.

Prior to treatment a lightweight frame, shaped like a box is fitted around the head, pins are put into the frame to stabilise the patient into the correct position and reduced movement during the radiosurgery. The frame helps the surgeon accurately identify the position of the abnormal target tissue.

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