Localizing moving targets and organs using motion-managed CTs

Interfraction and Respiratory Organ Motion During Conformal Radiotherapy in Gastric Cancer

“…Investigators have examined respiratory amplitude on fluoroscopy (23,24) or by tracking the liver with a scintillation camera after 99 Tc administration (24,25). Ultrasonography (26)(27)(28), CT performed in voluntary breath hold expiration and inspiration (6,12,19), magnetic resonance imaging (29)(30)(31), and respiratory sorted CT imaging (4D CT) (13,17,32,33) have all been used more recently. The breath hold technique used in our study likely overestimated the excursion during normal quiet breathing.…”

“…Published data has addressed the respiratory motion of liver, pancreas (including liver and pancreatic tumors), kidneys, and diaphragm (6,11,12,(16)(17)(18). The practice at the Princess Margaret Hospital when this study began involved the use of real-time fluoroscopy and application of a minimal 1-cm (0.5-cm posteriorly) PTV margin beyond the CTV.…”

Extra-cranial Stereotactic Radiation Therapy (ESRT) in the treatment of inoperable stage 1 & 2 non-small-cell lung cancer patients with highly mobile tumours: a literature review

“…10,11 Additionally, Respiratory Induced Tumour Motion (RITM) during a course of radiotherapy treatment will have an effect on accurate target coverage; thoracic tumours have been observed to move more than 2 cm (ref. 12) and unless there is some way of correctly assessing or inferring tumour position during treatment, on an individual basis, the margin that needs to be applied to account for the motion is too large to facilitate dose escalation. 12,13 Extra-cranial Stereotactic Radiation Therapy (ESRT) has been implemented using a variety of techniques to address the issue of RITM during treatment in a number of centres around the world.…”

“…12) and unless there is some way of correctly assessing or inferring tumour position during treatment, on an individual basis, the margin that needs to be applied to account for the motion is too large to facilitate dose escalation. 12,13 Extra-cranial Stereotactic Radiation Therapy (ESRT) has been implemented using a variety of techniques to address the issue of RITM during treatment in a number of centres around the world. 14À16 Localisation and targeting techniques in ESRT are similar to those developed and established in Intracranial Stereotactic Radiation Therapy (ISRT).…”

Performance Characteristics and Quality Assurance Aspects of Kilovoltage Cone-Beam CT on Medical Linear Accelerator

“…In both treatment techniques, the targets and relative surrounding critical tissues must be in the static state and repeated positioning would yield almost the same coordinates except where motion-gating technique is implemented. [7][8][9] The need for this higher degree of precision and accuracy has lead to the emergence of image-guided radiation therapy (IGRT) technologies.…”