Proposed Hydrogel-Implant Quality Score and a Matched-Pair Study for Prostate Radiation Therapy.

Purpose: SpaceOAR hydrogel has been Food and Drug Administration approved to reduce rectal toxicity in prostate radiation therapy. Training and certification for this procedure is performed by the manufacturer, without independent quality measures. We propose a Hydrogel-Implant Quality Score (HIQS) as a surrogate to quantify hydrogel placement accuracy, to assist clinicians in tracking their implant proficiency, and to support quality improvement.

Can automated treatment plans gain traction in the clinic?

Recently, there has been an increased interest in the feasibility and impact of automation within the field of medical dosimetry. While there have been many commercialized solutions for automatic treatment planning, the use of an application programming interface to achieve complete plan generation for specific treatment sites is a process only recently available for certain commercial vendors. Automatic plan generation for 20 prostate patients was achieved via a stand-alone automated planning script that accessed a knowledge-based planning solution.

Direct comparison between surface imaging and orthogonal radiographic imaging for SRS localization in phantom.

Purpose: Surface imaging (SI) offers a nonionizing, near real time alternative to radiographic imaging for intrafraction radiosurgery localization. In this work, we systematically compared a commercial SI system vs a commercial room mounted x-ray localization system in phantom.

Methods: An anthropomorphic head phantom with fiducial markers was imaged with linear accelerator on-board x-ray imaging, SI, and room mounted x-ray imaging (RM) at ±45° and ±90° couch angles for three different head tilts and six different isocenters (72 total positions).

Evaluation of offline adaptive planning techniques in image-guided brachytherapy of cervical cancer.

Modern three-dimensional image-guided intracavitary high dose rate (HDR) brachytherapy is often used in combination with external beam radiotherapy (EBRT) to manage cervical cancer. Intrafraction motion of critical organs relative to the HDR applicator in the time between the planning CT and treatment delivery can cause marked deviations between the planned and delivered doses. This study examines offline adaptive planning techniques that may reduce intrafraction uncertainties by shortening the time between the planning CT and treatment delivery.

A hybrid planning strategy for stereotactic body radiation therapy of early stage non-small-cell lung cancer.

Currently dynamic conformal arcs (DCA) and volumetric modulated arc therapy (VMAT) are two popular planning techniques to treat lung stereotactic body radiation therapy (SBRT) patients. Of the two, DCA has advantages in terms of multi-leaf collimator (MLC) motion, positioning error, and delivery efficiency. However, VMAT is often the choice when critical organ sparing becomes important.

Comparison of the progressive resolution optimizer and photon optimizer in VMAT optimization for stereotactic treatments.

The photon optimization (PO) algorithm was recently released by Varian Medical Systems to improve volumetric modulated arc therapy (VMAT) optimization within Eclipse (Version 13.5). The purpose of this study is to compare the PO algorithm with its predecessor, progressive resolution optimizer (PRO) for lung SBRT and brain SRS treatments.

Do we need a new CT scan for retreatment of intracranial SRS patients?

Purpose: To determine if the treatment planning computed tomography scan (CT) from an initial intracranial stereotactic radiosurgery (SRS) treatment can be used for repeat courses of SRS.

Methods And Materials: Twenty-five patients with 40 brain metastases that received multiple courses of SRS were retrospectively studied. Magnetic resonance scans from repeat SRS (rMR) courses were registered to CT scans from the initial SRS (iCT) and repeat SRS (rCT).

A novel method for radiotherapy patient identification using surface imaging.

Performing a procedure on the wrong patient or site is one of the greatest errors that can occur in medicine. The addition of automation has been shown to reduce errors in many processes. In this work we explore the use of an automated patient identification process using optical surface imaging for radiotherapy treatments.

A prospective evaluation of open face masks for head and neck radiation therapy.

Purpose: Head and neck (HN) radiation therapy patients are typically immobilized with closed thermoplastic masks that cover the face and may cause discomfort. In this work, we examine the use of open masks for HN radiation therapy.

Methods And Materials: Fifty HN patients were prospectively randomized into 2 groups (25 closed masks, 25 open masks).