It is often used in proton therapy, to reduce unnecessary radiation exposure to surrounding non-cancerous cells.
Ionizing radiation photons or x-rays (IMRT) use pencil beam scanning to precisely target a tumor.
Several charged particles devices used with Proton therapy cancer centers use pencil beam scanning.
[2] The newer proton therapy machines use a pencil beam scanning technology.
[4] The Paul Scherrer Institute was the developer of spot beam.