Isocenter in

aerial photography Aerial photography (or airborne imagery) is the taking of photographs from an aircraft or other airborne platforms. When taking motion pictures, it is also known as aerial videography. Platforms for aerial photography include fixed-wing aircra ...

: it is a point where a line cuts an angle of 90 degree of tier/2. It is the point on the aerial photo platform that directly falls on a line half-way between the Principal point and the Nadir point. In imaging physics and

radiation oncology Radiation therapy or radiotherapy, often abbreviated RT, RTx, or XRT, is a therapy using ionizing radiation, generally provided as part of cancer treatment to control or kill malignant cells and normally delivered by a linear accelerator. Radia ...

, the ''isocenter'' is termed as the point in space through which the central rays of the radiation beams pass. In

there is typically talk of two isocenters: *radiation isocenter and *mechanical isocenter. Radiation isocenter is the point in space through which the central beam of radiation passes whereas the mechanical isocenter is the point where optical beams intersect. The two are closely related but differ in terms of their functionality and working in Space. Isocenter definition in

Radiotherapy Radiation therapy or radiotherapy, often abbreviated RT, RTx, or XRT, is a therapy using ionizing radiation, generally provided as part of cancer treatment to control or kill malignant cells and normally delivered by a linear accelerator. Radia ...

: The point in space relative to the treatment machine about which various components of the linac rotate. The

gantry A gantry is an overhead bridge-like structure supporting equipment such as a crane, signals, or cameras. Devices and structures *Gantry (medical), cylindrical scanner assembly used for medical 3D-imaging or treatment *Gantry (transport), an over ...

rotation defines a horizontal axis which cuts a vertical axis defined by the rotation of the treatment couch. The treatment collimators also rotate about an axis pointing through the isocentre. The ''source to isocenter distance'' (SIsoD) can be an important parameter to control in determining patient exposure and image quality in diagnostic

computed tomography A computed tomography scan (CT scan; formerly called computed axial tomography scan or CAT scan) is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers ...

and

fluoroscopy Fluoroscopy () is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope () allows a physician to see the internal structure and functio ...

References

External links

Description of radiation isocenter

Isocenter verification for linac-based stereotactic radiation therapy: review of principles and techniques
Radiation therapy Medical physics {{nuclear-med-stub