Non-coplanar lung SABR treatments delivered with a gantry-mounted x-ray tube.

To create two non-coplanar, stereotactic ablative radiotherapy (SABR) lung patient treatment plans compliant with the radiation therapy oncology group (RTOG) 0813 dosimetric criteria using a simple, isocentric, therapy with kilovoltage arcs (SITKA) system designed to provide low cost external radiotherapy treatments for low- and middle-income countries (LMICs).A treatment machine design has been proposed featuring a 320 kVp x-ray tube mounted on a gantry. A deep learning cone-beam CT (CBCT) to synthetic CT (sCT) method was employed to remove the additional cost of planning CTs.

Metal artifact correction in photon-counting detector computed tomography: metal trace replacement using high-energy data.

Background: Metal artifacts have been an outstanding issue in computed tomography (CT) since its first uses in the clinic and continue to interfere. Metal artifact reduction (MAR) methods continue to be proposed and photon-counting detectors (PCDs) have recently been the subject of research toward this purpose. PCDs offer the ability to distinguish the energy of incident x-rays and sort them in a set number of energy bins.

Investigation of image quality of MV and kV CBCT with low-Z beams and high DQE detector.

Purpose: To investigate cone beam computed tomography (CBCT) image quality using novel combinations of kilovoltage (kV) and megavoltage (MV) beams and detector materials.

Methods: MV and kV CBCT imaging was simulated using the Fastcat hybrid Monte Carlo application. CBCT imaging with various beam energies was investigated: 2.

Experimental validation of Fastcat kV and MV cone beam CT (CBCT) simulator.

Purpose: To experimentally validate the Fastcat cone beam computed tomography (CBCT) simulator against kV and MV CBCT images acquired with a Varian Truebeam linac.

Methods: kV and MV CBCT images of a Catphan 504 phantom were acquired using a 100 kVp beam with the on-board imager (OBI) and a 6 MV treatment beam with the electronic portal imaging device (EPID), respectively. The kV Fastcat simulation was performed using detailed models of the x-ray source, bowtie filter, a high resolution voxelized virtual Catphan phantom, anti-scatter grid, and the CsI scintillating detector.

fastCAT: Fast cone beam CT (CBCT) simulation.

Purpose: To develop fastCAT, a fast cone-beam computed tomography (CBCT) simulator. fastCAT uses pre-calculated Monte Carlo (MC) CBCT phantom-specific scatter and detector response functions to reduce simulation time for megavoltage (MV) and kilovoltage (kV) CBCT imaging.

Methods: Pre-calculated x-ray beam energy spectra, detector optical spread functions and energy deposition, and phantom scatter kernels are combined with GPU raytracing to produce CBCT volumes.

Photon-counting computed tomography of lanthanide contrast agents with a high-flux 330-m-pitch cadmium zinc telluride detector in a table-top system.

We present photon-counting computed tomography (PCCT) imaging of contrast agent triplets similar in atomic number ( ) achieved with a high-flux cadmium zinc telluride (CZT) detector. The table-top PCCT imaging system included a -pitch CZT detector of size capable of using six energy bins. Four 3D-printed 3-cm-diameter phantoms each contained seven 6-mm-diameter vials with water and low and high concentration solutions of various contrast agents.