Precise image-guided irradiation of small animals: a flexible non-profit platform

Abstract

Preclinical in vivo studies using small animals are essential to develop new therapeutic options in radiation oncology. Of particular interest are orthotopic tumour models, which better reflect the clinical situation in terms of growth patterns and microenvironmental parameters of the tumour as well as the interplay of tumours with the surrounding normal tissues. Such orthotopic models increase the technical demands and the complexity of preclinical studies as local irradiation with therapeutically relevant doses requires image-guided target localisation and accurate beam application. Moreover, advanced imaging techniques are needed for monitoring treatment outcome. We present a novel small animal image-guided radiation therapy (SAIGRT) system, which allows for precise and accurate, conformal irradiation and x-ray imaging of small animals. High accuracy is achieved by its robust construction, the precise movement of its components and a fast high-resolution flat-panel detector. Field forming and x-ray imaging is accomplished close to the animal resulting in a small penumbra and a high image quality. Feasibility for irradiating orthotopic models has been proven using lung tumour and glioblastoma models in mice. The SAIGRT system provides a flexible, non-profit academic research platform which can be adapted to specific experimental needs and therefore enables systematic preclinical trials in multicentre research networks.

Scattered Dose Calculations and Measurements in a Life-Like Mouse Phantom

“…The widespread usage of small animal models has spurred development of physical phantoms of mice as well. Simple mouse phantoms, which are often no more than a tube with slots for the insertion of a detector, are prevalent for dosimetry (3, 5, 6, 21). The rise in popularity and capability of rapid prototyping tools, such as 3D printers and computer controlled milling machines, has allowed for a new generation of physical mouse phantoms with intricate features that closely mimic the animals they represent.…”

Radiation Biology Irradiator Dose Verification Survey

“…Thus, recent research has pushed to create systems which mimic the capabilities of human radiotherapy on small animal models. A number of experimental small animal irradiation systems have been developed in the past ten years, with some even becoming commercially available (2)(3)(4). These systems have high-resolution imaging capabilities, technically precise robotic movements, and energies scaled to match the small animal geometries.…”

“…The widespread usage of small animal models has spurred development of physical phantoms of mice as well. Simple mouse phantoms, which are often no more than a tube with slots for the insertion of a detector, are prevalent for dosimetry (3,5,6,21). The rise in popularity and capability of rapid prototyping tools, such as 3D printers and computer controlled milling machines, has allowed for a new generation of physical mouse phantoms with intricate features that closely mimic the animals they represent.…”

A method to combine target volume data from 3D and 4D planned thoracic radiotherapy patient cohorts for machine learning applications

“…Non-commercial research machines SARRP system (Xstrahl Ltd, UK) [8][9][10]; X-RAD 225Cx (Precision X-ray Inc., USA) [11] Brachytherapy-based system using an Ir-192 source [12] System based on the GE micro-CT scanner [5,13,14] X-ray image guidance system [15] Carbon nanotube [16] SAIGRT system [17] question how many tissue types are needed for proper dose calculation accuracy [34][35][36]. Dose reporting is another concern.…”