Your Gamma Knife Radiosurgery Treatment Day
A frame which is secured to the head, is crucial to the treatment and forms the basis for accurately identifying the position of the abnormal target tissue and also for securely positioning you for the gamma knife radiosurgery treatment.
After a light breakfast on the day of treatment you will be transferred to a clinical room, shown the frame and prepared for its application. The process of positioning the frame takes approximately 10 minutes. Some discomfort may be experienced as local anaesthetic is applied at the points of contact with the head.
Measurements are made over the surface of the scalp so that the size, shape and exact location of the head are known with reference to the frame.
You will then have an MRI and/or CT scan (and an angiogram where appropriate) which provides up-to-date images of the abnormalities to be treated. These images have special markers on, which enable the precise position of the abnormality to be determined.
When your MRI scan is complete you will be taken to the Gamma Knife Suite where refreshments and a well deserved break is taken. This is when your individualised treatment plan will be constructed by the Physics team. This may take some time as a NeuroRadiologist, Physics staff and the Radiosurgery Consultant are all involved, (the complexity of the condition being treated may also affect this). The Radiographers looking after you will do their best to keep you advised of how the process is going.
Preparing for an MRI scan
This shows how you will be positioned on the bed of the MRI scanner, once that you are positioned and comfortable the scan takes approx 20mins. It may be necessary to give contrast dye via a small canula in your arm.
This shows a plan that has just had the area for treatment marked up. the next image above is a final treatment plan. A number of radiation fields of different sizes are used to formulate the Gamma Knife treatment plan which when ready is sent to the gamma knife control in preparation for treatment delivery. When your plan has been approved and further checked you will be taken into the treatment room to start your treatment. The frame is used to precisely position your head to the planned positions within the treatment machine.
The treatment staff will carefully explain everything, making you as comfortable as possible and only when you are happy, does the treatment commence.
Prior to the treatment we may take a quick CT scan around your head to verify that you are correctly positioned for treatment.
The patient couch then moves into the central body of the treatment unit (much like an MRI scanner) in order to deliver the first field of the Gamma Knife treatment. For your comfort and safety the Treatment Staff will watch over the treatment process via video cameras. During your treatment you will be able to relax and listen to music whilst still being able to talk to the Radiographers via an intercom as and when you wish. The treatment couch will move in order to accurately position you for each treatment field and you may sense thiese gentle movements of the couch.
The time taken to deliver the treatment can vary from around 30 minutes up-to several hours depending upon the size/shape of the treatment area and the sometimes intricate nature of the individual Gamma Knife treatment plan.