What is source to skin distance?

Source-skin distance (SSD) means the distance from the source to the center of the entrant x-ray field in the plane tangent to the patient skin surface. Spot-film device means a device in- tended to transport and/or position a radiographic image receptor between the x-ray source and fluoroscopic image receptor.

What is skin distance?

The distance between the focal spot of the x-ray tube (where x-rays are produced) marked with a red dot on the intra-oral x-ray head to the skin surface of the patient.

What is source distance?

Source Surface Distance (SSD) The SSD is the distance from the source (the target for photons; a virtual source for electrons) to the surface of the patient or phantom.

What is target to skin distance?

The target to skin distance (TSD) is one of the most common measurements taken for radiation therapy. This value is used for determination of the depth at which the treatment time is calculated. The optical distance indicator (ODI) is most often used to find the TSD.

What is source to axis distance?

The source-axis distance (SAD) is a treatment machine design parameter that affects integral dose, dose rate and patient clearance. The aim of this work was to investigate the effect of source-axis distance on integral dose for conformal arc therapy.

What is SSD in radiation?

Source to skin distance (SSD) is almost used as an important reference to examine the depth of an x- ray in radiotherapist treatment [1]. The aim of this study is to characterize and to measure the dosimetric output of 6 and 10 MV Varian Clinac CX linear accelerator using the variation of SSD.

What is SSD in radiography?

What is the image distance?

The image distance is simply the distance from the object to the thin lines. The image distance is the distance from the thin lens to the image. The focal length is a characteristic of the thin lens, and it specifics the distance at which parallel rays come to a focus.

What is SSD in radiotherapy?

What is CAX in radiation therapy?

The radiation field edges in each image were used to determine the center of the radiation field. In this study, the CAX was defined as a line passing through the source spot and the center of the radiation field.

What is difference between SSD and sad in radiotherapy?

Modern photon beam radiotherapy is carried out with a variety of beam energies and field sizes under one of two set-up conventions: a constant source to surface distance (SSD) for all beams or an isocentric set-up with a constant source to axis distance (SAD).

What is FSD in radiotherapy?

[*A frequently used alternative term for the ‘focus to skin distance’ ( FSD ) is the ‘source to skin distance’ ( SSD ).] 4.4. Manual calculation of the ‘depth dose’ The radiation dose that is prescribed by the oncologist is the dose to the point of treatment.