What is half beam block in radiotherapy?
Introduction: Single isocentre half-beam block (HBB) technique permits the avoidance of hot and cold spots. This technique is very useful in sparing the underlying ipsilateral lung and heart, if the left breast is treated.
What type of beam is used in radiation therapy?
Most radiation therapy machines use photon beams. Photons are also used in x-rays, but x-rays use lower doses. Photon beams can reach tumors deep in the body.
What is block in radiotherapy?
Custom blocks are the most commonly used field shaping device in radiotherapy. They offer many advantages in daily clinical use. However, as with all accessories used for patient treatments, care must be taken with their use.
What are the four types of radiation therapies?
The types of external-beam radiation therapy are:
- Three-dimensional conformal radiation therapy (3D-CRT).
- Intensity modulated radiation therapy (IMRT).
- Proton beam therapy.
- Image-guided radiation therapy (IGRT).
- Stereotactic radiation therapy (SRT).
- Permanent implants.
- Temporary internal radiation therapy.
Is external beam radiation painful?
The linear accelerator machine may rotate around your body to deliver radiation beams from different directions. You lie still and breathe normally during the treatment. Your radiation therapy team stays nearby in a room with video and audio connections so that you can talk to each other. You shouldn’t feel any pain.
What are the three types of radiation therapy?
Three common types of internal radiation therapy include:
- Brachytherapy involves radioactive material that is implanted in the body.
- Intraoperative radiation therapy (IORT) is used to treat an exposed tumor during cancer surgery.
- Stereotactic radiosurgery (SRS) is not actually surgery.
Why are wedges used in radiotherapy?
In radiation oncology, wedge filters are commonly used to improve the dose uniformity in the target volume. They can be used as missing tissue compensators or wedge pairs to alter the shape of isodose curves so that two beams can be angled with a small hinge angle at a target volume without creating a hotspot.
What are the treatment planning methods for HNC using external beam radiotherapy?
The treatment planning methods for HNC using external-beam radiotherapy have evolved from the traditional three-field technique in the early days to intensity-modulated radiotherapy (IMRT), and recently to the more efficient volumetric modulated arc therapy (VMAT).
What are the advantages of rotatable half-beam blocks?
The rotatable half-beam block solution offers a number of advantages for those therapy machines restricted to gantry, collimator, and turntable rotation. The rotatable half-beam block may be used for all three fields, thus offering a simplification of the mechanical accessories required to implement the technique.
What is the typical beam arrangement for the treatment of breast cancer?
The typical beam arrangement for the treatment of bilateral tumors consists of 9 coplanar 6 MV photon beams evenly distributed around the patient (0°, 40°, 80°, 120°, 160°, 200°, 240°, 280°, and 320°). The typical beam arrangement for the treatment of unilateral cases consists of 7 coplanar beams, angled from the tumor side.
What is a protractor used for on a rotatable half beam?
Photograph of the rotatable half-beam block assembly (block, plastic inset, turntable, tray). An alignment protractor, identical to that used by Svensson et al.,’ is used to aid and verify the alignment of the three fields along the match plane.