Stereotactic MR-guided online adaptive radiotherapy reirradiation (SMART reRT) for locally recurrent pancreatic adenocarcinoma: A case report
Introduction: Stereotactic MR-guided online adaptive radiation therapy (SMART) has demonstrated a superior radiotherapeutic ratio for pancreatic patients, by enabling dose escalation while minimizing the dose to the proximal gastrointestinal organs at risk through online adaptive radiotherapy. The safe delivery of stereotactic body radiation therapy (SBRT) is of particular importance in the reirradiation setting and has been historically limited to CT-based nonadaptive modalities. Herein, we report the first use of online adaptive radiotherapy in the reirradiation setting, specifically for treatment of locally recurrent pa...
Source: Medical Dosimetry - June 10, 2021 Category: Radiology Authors: Delia G. Doty, Michael D. Chuong, Andres G. Gomez, John Bryant, Jessika Contreras, Tino Romaguera, Diane Alvarez, Rupesh Kotecha, Minesh P. Mehta, Alonso N. Gutierrez, Kathryn E. Mittauer Source Type: research

Lens dose to standing patients treated with electrons to the hand
This study measures the dose beside an applicator at a depth of 3 mm in a phantom as an estimate of lens dose for such patients. The lens dose is investigated as a function of height, distance, beam energy, applicator size, and cutout fill on a Varian Trilogy linear accelerator. (Source: Medical Dosimetry)
Source: Medical Dosimetry - May 28, 2021 Category: Radiology Authors: Jonathon Van Schelt Source Type: research

Comment on: “Effects of gas-filled temporary breast tissue expanders on radiation dose from modulated rotational photon beams”
We welcome the article “Effects of gas-filled temporary breast tissue expanders on radiation dose from modulated rotational photon beams”1 by Kairn et al., which was recently published in Medical Dosimetry. We would like to congratulate with the authors for their excellent study on effects of radiotherapy on breast ti ssue expanders in post mastectomy reconstructive surgery, a current and controversial issue given the high rate of complications. In this regard, we sincerely appreciate the citation of our article on the positive effect of autologous fat grafting (AFG) in combination with second stage breast recons truct...
Source: Medical Dosimetry - May 24, 2021 Category: Radiology Authors: Andrea Battistini, Valeriano Vinci, Maria Angela Romeo, Benedetta Agnelli, Corrado Tinterri, Francesco Klinger Tags: Letter to the Editor Source Type: research

Incidence of work related musculoskeletal disorders in medical dosimetry
Musculoskeletal disorders (MSDs) account for almost 70 million physician office visits per year in the United States and are the most common workplace injuries. These are conditions involving the nerves, tendons, muscles, and supporting structures of the body. Previous studies have concluded that computer users are at high risk of developing work-related musculoskeletal disorders (WRMSDs). As computer users, medical dosimetrists are at risk of developing WRMSDs, yet there is a lack of information regarding the incidence of WRMSDs among medical dosimetrists. (Source: Medical Dosimetry)
Source: Medical Dosimetry - May 23, 2021 Category: Radiology Authors: Alicia Wilson, John Keefe, Hanaan Habibulla, Nishele Lenards, Ashley Hunzeker, Matt Tobler, Sabrina Zeiler, Ashley Fellows Source Type: research

Dosimetric comparison and secondary malignancy risk estimation for linac-based and robotic stereotactic radiotherapy in uveal melanoma
It was aimed to investigate the dosimetric differences among linac-based and robotic stereotactic radiotherapy (SRT) techniques for the treatment of uveal melanoma and to evaluate secondary malignancy risks for these different SRT techniques. Ten patients who received robotic SRT with CyberKnife were retrospectively included in this study. A total dose of 54 Gy in three fractions was prescribed to the planning target volume (PTV). For each patient, non-coplanar micro-multileaf collimator based dynamic conformal arc (DCA), intensity-modulated radiotherapy (IMRT) and circular cone based DCA (cDCA) plans were generated. (Sour...
Source: Medical Dosimetry - May 16, 2021 Category: Radiology Authors: Fatih Biltekin, Gozde Yazici Source Type: research

A new index for evaluating the fit of dose distribution to target volume: Dose distribution fix index
To develop a new dose evaluation index, fit index (FI), to help evaluate the fit between isodose surfaces at different percentages of the prescription dose and the target volume. Two types of FI, differential and cumulative, were defined. The differential fit index (dFI) was defined as the ratio of the integral dose of volume occupied by an isodose surface to the integral dose of the planning target volume. The cumulative fit index (cFI) was defined as the integral of dFI from the minimum dose of clinical significance to the 100% prescription dose. (Source: Medical Dosimetry)
Source: Medical Dosimetry - May 14, 2021 Category: Radiology Authors: Lingling Yan, Yingjie Xu, Bin Liang, Jianrong Dai Tags: Dosimetry Source Type: research

Multiple case dosimetric evaluation of VMAT scalp irradiation using 3D milled bolus
Adequate dose homogeneity and full prescription dose delivery to the scalp still remains a dosimetric problem during scalp irradiation due to the anatomical shape of the cranium. Confounding variables such as gravity, the irregular and convex shape of the cranium, air gaps between scalp surface and commercial bolus, and potential inconsistencies in a 3D printed bolus can negatively impact the dose delivered to the scalp surface during scalp irradiation. The purpose of this retrospective case study was to implement the use of a 3D milled rigid bolus technique combined with volumetric modulated arc therapy (VMAT) treatment p...
Source: Medical Dosimetry - May 12, 2021 Category: Radiology Authors: Zachary Casto, Michal Liu, Nishele Lenards, Ashley Hunzeker, Wesley Zoller, Dukagjin M Blakaj Source Type: research

Investigation of interfractional variation in lung tumor position under expiratory-phase breath hold using cone-beam computed tomography in stereotactic body radiation therapy
We investigated the interfractional variation in the tumor position during lung stereotactic body radiotherapy (SBRT) under expiratory-phase breath hold (BH) using cone-beam computed tomography (CBCT). (Source: Medical Dosimetry)
Source: Medical Dosimetry - May 11, 2021 Category: Radiology Authors: Hideharu Miura, Shuichi Ozawa, Minoru Nakao, Yoshiko Doi, Yoshinori Adachi, Masahiko Kenjo, Yasushi Nagata Source Type: research

Impact of treatment planning quality assurance software on volumetric-modulated arc therapy plans for prostate cancer patients
Software that evaluates the quality of treatment plans (PlanIQTM) has become commercially available in recent years. It includes a feasibility assessment tool that provides the ideal dose volume histogram (DVH) for each organ at risk, based on the ideal dose falloff from the prescribed dose at the target boundary. It is important to investigate whether the PlanIQTM assessment tool (Feasibility DVHTM) can assist treatment planners who have limited to no experience in treatment planning. Therefore, the present study aimed to evaluate this tool's usefulness for improving the quality of treatment plans. (Source: Medical Dosimetry)
Source: Medical Dosimetry - May 7, 2021 Category: Radiology Authors: Motoharu Sasaki, Yuji Nakaguchi, Takeshi Kamomae, Akimi Kajino, Hitoshi Ikushima Source Type: research

Measuring foetal dose from tomotherapy treatments
This study presents the first investigation of foetal doses delivered during helical tomotherapy treatments. Six treatment plans were delivered to an anthropomorphic phantom using a tomotherapy machine. These included treatments of the brain, unilateral and bilateral head-and-neck, chest wall, and upper lung. (Source: Medical Dosimetry)
Source: Medical Dosimetry - April 29, 2021 Category: Radiology Authors: Samuel C. Peet, Tanya Kairn, Craig M. Lancaster, Jamie V. Trapp, Steven R. Sylvander, Scott B. Crowe Tags: Medical physics Source Type: research

DIBH-IMRT for RTOG 1304, Cancer of the left breast: A case study
The purpose of this case study is to describe an external beam radiation therapy planning technique for carcinoma of the left breast. A female patient on protocol NSABP B-51/RTOG 1304 presented with unusual anatomy and large habitus. Deep inspiration breath-hold (DIBH) IMRT was used in conjunction a DIBH-3D conformal radiotherapy (3DCRT) tangential boost plan to meet the dose criteria for protocol compliance. Traditionally 3DCRT planning using a DIBH technique would be used for both billing authorization and as DIBH-IMRT involves a longer treatment time and more difficulty in terms of patient compliance; however, the patie...
Source: Medical Dosimetry - April 29, 2021 Category: Radiology Authors: Jeannie Anderson, Frank Guoqing Fan Source Type: research

Dual-energy computed tomography image-based volumetric-modulated arc therapy planning for reducing the effect of contrast-enhanced agent on dose distributions
To compare the effect of a contrast-enhanced (CE) agent on volumetric-modulated arc therapy plans based on four types of images —virtual monochromatic images (VMIs) captured at 70 and 140 keV (namely VMI70 and VMI140, respectively), water density image (WDI), and virtual non-contrast image (VNC) generated using a dual-energy computed tomography (DECT) system. A tissue characterization phantom and a multi-energy phantom wer e scanned, and VMI70, VMI140, WDI, and VNC were retrospectively reconstructed. (Source: Medical Dosimetry)
Source: Medical Dosimetry - April 28, 2021 Category: Radiology Authors: Shingo Ohira, Riho Komiyama, Yuhei Koike, Hayate Washio, Naoyuki Kanayama, Shoki Inui, Yoshihiro Ueda, Masayoshi Miyazaki, Masahiko Koizumi, Teruki Teshima Source Type: research

Minimizing clearance issues with prone breast patients on Varian linear accelerators through isocenter placement
The prone position is frequently used for breast irradiation in an effort to minimize dose to normal tissue and reduce skin toxicities. Immobilization required for prone breast irradiation can cause collision issues with the linear accelerator, disrupting treatment and negatively affecting the patient experience. The purpose of this retrospective study was to determine if an isocenter location guideline could be developed to prevent collisions with the prone breast immobilization device and gantry head, while still creating a clinically acceptable treatment plan. (Source: Medical Dosimetry)
Source: Medical Dosimetry - April 24, 2021 Category: Radiology Authors: Lauren Wilson, Rob Rohe, Nishele Lenards, Ashley Hunzeker, Matt Tobler, Sabrina Zeiler, Ashley Fellows Source Type: research

Design of a motion simulation system to assist respiratory gating for radiation therapy
Stereotactic ablative radiotherapy (SABR) aims to deliver high doses of radiation to kill cancer cells and shrink tumors in less than or equal to 6 fractions. However, organ motion during treatment is a challenging issue for this kind of technique. We develop a control system via Bluetooth technology to simulate and correct body motion during SABR. Methods: Radiation doses were analyzed, and the radiation damage protection capability was checked by external beam therapy 3 (EBT3) films irradiated by a linear accelerator. (Source: Medical Dosimetry)
Source: Medical Dosimetry - April 24, 2021 Category: Radiology Authors: Jian-Kuen Wu, Shih-Han Chen, Feng-Ming Hsu, Shu-Hsien Liao, Yu-Jen Wang Source Type: research

Convolutional neural network and transfer learning for dose volume histogram prediction for prostate cancer radiotherapy
To adopt a transfer learning approach and establish a convolutional neural network (CNN) model for the prediction of rectum and bladder dose-volume histograms (DVH) in prostate patients treated with a VMAT technique. One hundred forty-four VMAT patients with intermediate or high-risk prostate cancer were included in this study. Data were split into two sets: 120 and 24 patients, respectively. The second set was used for final validation. To ensure the accuracy of the training data, we developed a ground-truth analysis for detecting and correcting for all potential outliers. (Source: Medical Dosimetry)
Source: Medical Dosimetry - April 22, 2021 Category: Radiology Authors: Eva M. Ambroa, Jaime P érez-Alija, Pedro Gallego Tags: Research Article Source Type: research