Comparison of perioperative and subacute postoperative complications between LDR and HDR monotherapy brachytherapy for prostate cancer.

Purpose: We aim to investigate perioperative and subacute postoperative complications in patients undergoing LDR or HDR monotherapy for prostate cancer. We hypothesize a low rate of complications, and a favorable toxicity profile in patients treated with HDR compared to LDR.

Materials And Methods: A prospectively collected institutional database was queried for patients treated with HDR or LDR prostate monotherapy between 1998 and 2021.

A dosimetric analysis of rectal hydrogel spacer use in patients with recurrent prostate cancer undergoing salvage high-dose-rate brachytherapy.

Purpose: We hypothesize rectal hydrogel spacer (RHS) improves rectal dosimetry in patients undergoing salvage high-dose-rate brachytherapy (HDR-BT) for intact, recurrent prostate cancer (PC).

Methods And Materials: A prospectively collected institutional database was queried for recurrent PC patients treated with salvage HDR-BT from September 2015 to November 2021. Patients were offered RHS beginning June 2019.

2D IMRT QA passing rate dependency on coronal plane.

Intensity modulated radiation therapy (IMRT) delivery involves a complex series of beam angles and multileaf collimator (MLC) arrangements, requiring quality assurance to be performed to validate delivery before treatment. The purpose of this work is to investigate the effect of dose gradient on quality assurance (QA) passing rate. Many (n = 40) IMRT plans were delivered and measured using a 2D planar array of ion chambers; additionally, eleven plans were measured at several coronal planes.

Evaluating suggested stricter gamma criteria for linac-based patient-specific delivery QA in the conventional and SBRT environments.

Purpose: To evaluate AAPM TG-218 recommended tolerances for IMRT QA for conventional and SBRT delivery.

Methods: QA analysis was repeated for 150 IMRT/VMAT patients with varying gamma criteria. True composite delivery was utilized, corrected for detector and output variation.

Practical Clinical Implementation of the Special Physics Consultation Process in the Re-irradiation Environment.

Purpose: The purpose of this work is to present a practical, structured process allowing for consistent, safe radiation therapy delivery in the re-treatment environment.

Methods And Materials: A process for reirradiation is described with documentation in the form of a special physics consultation. Data acquisition associated with previous treatment is described from highest to lowest quality.

Robotic radiosurgery system patient-specific QA for extracranial treatments using the planar ion chamber array and the cylindrical diode array.

Robotic radiosurgery system has been increasingly employed for extracranial treatments. This work is aimed to study the feasibility of a cylindrical diode array and a planar ion chamber array for patient-specific QA with this robotic radiosurgery system and compare their performance. Fiducial markers were implanted in both systems to enable image-based setup.

Planning target volume-to-skin proximity for head-and-neck intensity modulated radiation therapy treatment planning.

Purpose: The goal of this work is to evaluate planning target volume (PTV)-to-skin proximity versus plan quality as well as the effects of calculation voxel size on dose uncertainty in the surface region.

Methods And Materials: A right-sided clinical target volume with the lateral border 5 mm from the surface was delineated on the computed tomographic data of a head-and-neck phantom. A 5-mm PTV expansion was generated except laterally where distances of 0-5 mm were used.

Measurement comparison and Monte Carlo analysis for volumetric-modulated arc therapy (VMAT) delivery verification using the ArcCHECK dosimetry system.

The objective of this study is to validate the capabilities of a cylindrical diode array system for volumetric-modulated arc therapy (VMAT) treatment quality assurance (QA). The VMAT plans were generated by the Eclipse treatment planning system (TPS) with the analytical anisotropic algorithm (AAA) for dose calculation. An in-house Monte Carlo (MC) code was utilized as a validation tool for the TPS calculations and the ArcCHECK measurements.