A framework for assumption-free assessment of imperfect geometry of a linac C-arms

TL;DR

This paper introduces a geometric algebra-based framework for assessing and calibrating the imperfect geometry of radiotherapy C-arms, providing closed-form solutions for correction shifts at each gantry angle.

Contribution

It presents a novel geometric algebra approach and calibration methods for accurately determining and correcting C-arm geometry imperfections in radiotherapy devices.

Findings

Framework effectively models imperfect geometry.

Calibration methods yield precise correction shifts.

Closed-form solutions simplify implementation.

Abstract

In the present paper a general setup for determination of imperfect geometry of radiotherapeutic devices has been proposed that base on geometric algebra framework. To account for this imperfect geometry, two methods of a calibration were presented, consisting of determining for each angular position of a gantry a correction shift which must be applied to the origin of a laboratory frame of reference to place it along a radiation axis for this angular position. Closed form solutions for these corrections are provided.