Novel Methods for Ultra-low Dose CBCT in Angiography (LoDosAngio)

Programme

KS 24/26, KS 24/26, Bridge call 2024/01

Project coordination

Danube Private University, Ass.-Prof. Dr. Sepideh Hatamikia 

Project partners

• Medical University Vienna
• medPhoton GmbH
• University of Cambridge Department of Applied Mathematics and Theoretical Physics

Researchers involved at DPU

• Poorya Mohammadi Nassab
• Clemens Karner

Abstract

Cone-beam computed tomography (CBCT) angiography is increasingly being used in the interventional radiology suite to facilitate and guide interventional procedures. Modern angiography is performed by injecting a radio-opaque contrast agent into the blood vessel joint with 3D CBCT imaging to examine blood flows. Nowadays, the radiation dose introduced by CBCT to the patient is becoming a major concern. The requirement for superior image quality usually comes at the cost of high radiation dose that raises concerns for short-term and long-term radiation effects. In addition, it has been shown that such contrast agents can lead to various side effects in several different angiography applications. The overall goal of the planned project is to innovate and validate methods to significantly reduce the total radiation (and contrast agent) dose during CBCT angiography procedures. The basic concept is that a prior 3D image normally is available for such procedures and that is used to constrain the reconstruction of the later CBCT scan(s) acquired with a much lower radiation dose/projection number. In the planned project, we first aim to develop novel prior image informed reconstruction algorithms to reconstruct a subsequent CBCT image with substantially fewer projection numbers, and thus significantly reduce the radiation dose and speed up the acquisition process. An optimal compromise between the projection number and the contrast agent amount will also be researched with the goal to reduce the iodine-based contrast agent dose needed. Additionally, the compatibility of this approach with lower contrast CO2 contrast agent will be studied. As the second main objective of this project, we aim to develop novel source-detector CBCT trajectories to be used in conjunction with the proposed advanced prior image informed reconstruction algorithms in order to even further reduce the overall radiation dose and decrease scan time for extended (longitudinal) FOV imaging. The focus of this project is on applications for cerebral angiography and lower extremity angiography. In addition, we will verify the performance of the developed techniques on the Loop-X system (medPhoton, Salzburg, Austria). The results of this project may help to enable CBCT angiography with extremely low radiation dose, faster image acquisition, lower contrast agent and larger FOV, allowing for more optimal diagnosis and treatment, ultimately leading to greater safety and better outcomes for patients.

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