IMAGING

Use of Imaging Guidance in Treatment Room

Use of Imaging Guidance in Treatment Room

Introduction

Imaging has an important role to play in the management of patients with cancer. Imaging techniques are frequently used in the areas of detection, diagnosis and intervention. The use of imaging in the radiation therapy process has increased significantly in the last decade, from the treatment planning stage right through to the treatment room and follow up stages. The aim of these advances is to increase the accuracy and precision in the delivery of the dose to the tumour.

Image guidance in the treatment room enables a reduction in the effects of set-up errors and organ motion at the time of treatment using electronic portal imaging devices (EPID's) and cone beam CT e.g. the Elekta Synergy system and the Varian On Board Imaging system.

The tomotherapy is a type of radiotherapy, used to eradicate tumor pathologies or for palliative purposes, in which the radiation is emitted slice by slice (hence the use of the prefix Greek Volume, which means "slice"). This method of irradiation differs from other forms of external radiation therapy in which is irradiated simultaneously the entire volume of the tumor.

Advantages over Conventional Radiotherapy

Compared to conventional treatments, the tomotherapy allows more accurate irradiation of the target, with improved preservation of the surrounding tissues and the possibility in a same session of treating more than one target and with higher doses and circumscribed, with greater effectiveness of the treatment, the less commitment of the temporal structure and less effort for the patient.

The treatment can also be continuously adapted to the anatomical changes possibly occurring in the patient between a seat and the other.

Capture Images and Centering

In this phase anatomical data of the patient are obtained and the best practical solutions (position of the patient, accessories of immobilization) are identify in order to set the best possible treatment. The step of centering therefore does not involve the delivery of therapeutic doses, but has the sole purpose of "preparation technique" to the actual treatment. In the room diagnostic CT or PET -CT acquisition takes place and morphologic imaging in 3D of the lesion. This procedure is carried out in collaboration by the radiotherapist, from physical health , and medical radiology technician .

The technologist operates the first patient positioning and, together with the radiotherapist and physical health, identifies the correct coordinates tattooed centering the patient with indelible ink. Also prepares the means of ...