Color VISION for improved ultrasound visualization of brachytherapy needles.

Background: High dose rate brachytherapy is commonly used in the treatment of prostate cancer. Treatment planning is often performed under transrectal ultrasound (US) guidance, but brachytherapy needles can be challenging to digitize due to the presence of poor US conspicuity and imaging artifacts. The plan accuracy and quality, however, are dependent on the proper visualization of the needles with millimeter accuracy.

Pencil Beam Scanning Proton Therapy for Pregnant Patients With Brain and Head and Neck Cancers.

Purpose: When radiation therapy is medically necessary for pregnant patients, photon-based treatments (XRT) have traditionally been used, whereas proton radiation therapy (PRT) is avoided due to concerns about neutron dose. This retrospective study analyzes pregnant patients treated with XRT and models the equivalent dose that would have been delivered to the fetus with proton radiation compared with XRT. The purpose of this work is to provide a comprehensive analysis of pencil beam scanning proton therapy (PBS-PRT) for pregnant patients and to evaluate whether PBS-PRT should be the new standard of practice for treating pregnant patients with brain and head and neck cancers.

A new way to visualize prostate brachytherapy needles using ultrasound color Doppler and needle surface modifications.

Purpose: Suboptimal ultrasound conspicuity of the brachytherapy applicator can lead to inaccurate image reconstructions of the applicator resulting in decreased tumor control or increased normal tissue dose. This feasibility study aims to improve ultrasound conspicuity of high-dose rate (HDR) brachytherapy needles by modifying the surface of the needles to produce a color Doppler twinkling signature.

Materials And Methods: Surface modifications of standard 17-gauge titanium HDR brachytherapy needles included laser-scribing, application of polymethyl methacrylate (PMMA), and coating with a commercially available echogenic coating.

Intensity modulated high dose rate ocular brachytherapy using Se-75.

Purpose: We propose an alternative to LDR brachytherapy for the treatment of ocular melanomas by coupling intensity modulation, through the use of a gold shielded ring applicator, with a middle energy HDR brachytherapy source, Se-75. In this study, we computationally test this proposed design using MCNP6.

Methods And Materials: An array of discrete Se-75 sources is formed into a ring configuration within a gold shielded applicator, which collimates the beam to a conical shape.

Shielded high dose rate ocular brachytherapy using Yb-169.

We propose an approach for treating ocular melanoma using a new type of brachytherapy treatment device. This device couples Yb-169, a middle-energy high dose rate (HDR) brachytherapy source, with a gold shielded ring applicator to better conform radiation exposures to the tumor. In this study, we computationally test the dosimetric output of our proposed shielded ring applicator design using MCNP6 and validate it against an I-125 COMS plaque.

Monte Carlo dosimetric characterization of a new high dose rate Yb brachytherapy source and independent verification using a multipoint plastic scintillator detector.

Purpose: A prototype Yb source was developed in combination with a dynamic rotating platinum shield system (AIM-Brachy) to deliver intensity modulated brachytherapy (IMBT). The purpose of this study was to evaluate the dosimetric characteristics of the bare/shielded Yb source using Monte Carlo (MC) simulations and perform an independent dose verification using a dosimetry platform based on a multipoint plastic scintillator detector (mPSD).

Methods: The TG-43U1 dosimetric parameters were calculated for the source model using RapidBrachyMCTPS.