Cranial Stereotactic Patient

What is Cranial Stereotactic Radiosurgery (CSRS)?

Cranial Stereotactic Radiosurgery is a precise way of delivering a high dose of radiation therapy to a small, localised lesion or growth (benign or malignant) within the brain or cranium. This type of treatment requires a high degree of accuracy.

This treatment uses a standard linear accelerator (linac) with specialised accessories, immobilisation masks and treatment cones. The cones produce very small and accurate beams designed to deliver the dose of radiation therapy to the small treatment targets. The linac will move around the patient to deliver the treatment.

Generally, this type of radiation therapy requires one CT-Simulation appointment and then only one or two Treatment appointments.

What is involved in the CT-Simulation procedure?

CT-Simulation: This is the first step in the treatment planning process. This session generally will take 45-60 minutes and involves:

  • Making a thermoplastic immobilisation mask: This is important to help keep patients still, due to the high degree of accuracy required for treatment; the mask takes 30 minutes to “set”.
  • Patients are encouraged to bring music to listen to or there is a selection available.
  • Recording the set-up instructions; this is again important for the treatment set-up accuracy.
  • CT scanning of the treatment region.
  • Finally, an Education Session with the nursing staff. Nurses will discuss any treatment side-effects and the management of these. A separate Information Sheet will be provided.

The next appointment after CT-Simulation is the Treatment Appointment; this appointment is given at the time of CT-simulation. During the period of time between the CT-Simulation and Treatment appointments, the Radiation Oncology staff will prepare the treatment plan.

What happens on the treatment day?

The duration of this appointment depends on the treatment plan. Generally, the appointment is 45-60 minutes in duration. Treatment involves multiple ‘arcs’ which involves the machine rotating around the patient whilst the treatment is delivered.

The treatment procedure will involve:

  • Set up with immobilisation mask.
  • Recording and verifying the set-up measurements.
  • Taking X-rays to verify treatment accuracy.
  • Delivery of the treatment arcs.

The staff will inform you when they are ready to commence:

  • Staff exit the treatment room during the verification X-rays and treatment; however, patients are monitored by cameras and microphones.
  • X-rays will be taken prior to the treatment of each arc.
  • Each arc will take approximately 30 to 60 seconds to deliver.
  • Patients do not feel anything during treatment; a buzzing noise will be heard while the treatment arc is delivered.
  • The staff will re-enter the room for each treatment position.

When all arcs are treated, the mask will be removed.

After treatment care

  • Patients are required to spend a couple of hours in the department after treatment for monitoring.
  • Patients are given instructions regarding medications, follow-up appointments, and whom to contact in case of problems/emergencies.

Further information

If you have any concerns or for further information, please contact the Radiation Oncology Department.

Tel: 02 4014 3125
Monday-Fridays between 8:00am-4:30pm