What are organs at risk?

What are organs at risk?

The organs at risk (OARs) are the healthy tissues / organs placed near the clinical target volume (CTV) whose irradiation could cause damage that would make changes to the radiotherapy treatment plan. The heart, for example, in radiotherapy with LINAC of the left breast cancer, is an organ at risk.

What are the organs at risk in prostate cancer?

The organs at risk included the urinary bladder, rectum, and heads of the femur (left and right).

What is oar in radiotherapy?

What are the organs at risk in head and neck cancer radiotherapy?

The organs at risk are: cerebellum (c), brain stem (b), mandible (d), thyroid gland (e) and brain (a). Table 1 shows the doses received by the OARs for all patients.

What is a serial organ?

Classic serial organs are the spinal cord and intestinal tract where loss of function will occur if even a small length of either structure is sacrificed.

What is a parallel organ?

A parallel organ, like the liver or kidney, has redundancy built in, and a certain fraction of the organ parenchyma (or functional subunits) can be sacrificed and the organ will maintain function.

Is kidney a parallel organ?

The kidney is an example of an organ with parallel architecture. The smallest subunit is the nephron which function independently of each other. Therefore damage to a subunit does not affect the function of the other subunits. The spinal cord is a classical example of an organ with serial architecture.

What is a series organ?

Serial Organs are organs in which disabling any subunit causes the entire organ to fail. Parallel Organs are organs in which many or all of the subunits must be disabled to cause organ failure.

Is the liver a parallel organ?

Is the heart a parallel organ?

A classical example for a se- rial-parallel organ is the heart: the coronary arteries are a parallel and the myocardium a serial organ.

What is a Hammond RT3?

The Hammond RT3 is a bulky organ made up of all analog parts. It has two keyboards, each spanning about five octaves, in addition to the black preset keys on the left. It also has about two octaves of foot pedals. It is a fully polyphonic organ, with no limitations whatsoever.

What are parallel organs?