Chae‐Seon Hong

PURPOSE: The authors evaluated the effects of multileaf collimator (MLC) leaf width (2.5 vs. 5 mm) on dosimetric parameters and delivery efficiencies of intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) for head and neck (H&N) cancers. METHODS: The authors employed two types of mock phantoms: large-sized head and neck (LH&N) and small-sized C-shape (C-shape) phantoms. Step-and-shoot IMRT (S&S_IMRT) and VMAT treatment plans were designed with 2.5- and 5.0-mm

PURPOSE: To reduce radiation doses to the tongue, a patient-specific semi-customized tongue displacement device (SCTDD) was developed using a 3D printer (3DP) for head and neck (H&N) radiation therapy (RT). Dosimetric characteristics of the SCTDD were compared with those of a standard mouthpiece (SMP). MATERIALS AND METHODS: The SCTDD consists of three parts: a mouthpiece, connector with an immobilization mask, and tongue displacer, which can displace the tongue to the contralateral side of the

We first developed and validated the multivariable NTCP model for the lymphedema incidence in patients with breast cancer after radiation therapy. The multivariable NTCP model showed excellent performance and robustness in predicting lymphedema in both internal and completely independent external validations. The multivariable model for lymphedema prediction was robust and reliable for different treatment modalities and fractionation regimens.

AimsObjective evaluation of radiation dermatitis is important for analysing the correlation between the severity of radiation dermatitis and dose distribution in clinical practice and for reliable reporting in clinical trials. We developed a novel radiation dermatitis segmentation system based on convolutional neural networks (CNNs) to consistently evaluate radiation dermatitis.Materials and methodsThe radiation dermatitis segmentation system is designed to segment the radiation dermatitis occur

Purpose: The European Society of Radiation & Oncology and Advisory Committee on Radiation Oncology Practice (ESTRO-ACROP) presented new guidelines for clinical target volume (CTV) delineation in post-mastectomy radiation therapy (PMRT) after implant-based immediate breast reconstruction (IBR-i). This study evaluated the dosimetric characteristics, dosimetric accuracy, and delivery accuracy of these guidelines in volumetric modulated arc therapy (VMAT). Methods and Materials: This retrospecti

TH-3DCRT showed excellent carotid-sparing capability, while offering high efficiency and maintaining good PTV coverage.

Abstract Many situations are classified into more than two categories in real world. In this work, we consider ROCsurface and VUS, which are graphical representation methods for classification models with three categories.The standard criteria of AUC for the probability of default based on Basel II is extended to the VUS for ROCsurface; therefore, the standardized criteria of VUS for the classification model is proposed. The ranges ofAUC, K-S and mean difference statistics corresponding to VUS value

BACKGROUND: Tomotherapy-based total body irradiation (TBI) is performed using the head-first position (HFP) and feet-first position (FFP) due to treatment length exceeding the 135 cm limit. To reduce the dosimetric variation at the match lines, we propose and verify a volumetric gradient matching technique (VGMT) by combining TomoHelical (TH) and TomoDirect (TD) modes. METHODS: of solid water phantom. Planning target volume (PTV) was divided into upper, lower, and gradient volumes. The junction

Predicting the radiation dose‒toxicity relationship is important for local tumor control and patients' quality of life. We developed a first intuitive evaluation system that directly matches the three-dimensional (3D) dose distribution with the skin surface image of patients with radiation dermatitis (RD) to predict RD in patients undergoing radiotherapy. Using an RGB-D camera, 82 3D skin surface images (3DSSIs) were acquired from 19 patients who underwent radiotherapy. 3DSSI data acquired inclu

Radiation pneumonitis (RP) has been a challenging obstacle in treating stage III lung cancer patients. Beam angle optimization (BAO) technique for Tomotherapy was developed to reduce the normal lung dose for stage III non-small cell lung cancer (NSCLC). Comparative analyses on plan quality by 3 different Intensity-modulated radiation therapy (IMRT) methods with BAO were done. Ten consecutive stage IIIB NSCLC patients receiving linac-based static IMRT (L-IMRT) with total 66 Gy in 33 fractions to

PURPOSE: This study aimed to investigate the parameters with a significant impact on delivery quality assurance (DQA) failure and analyze the planning parameters as possible predictors of DQA failure for helical tomotherapy. METHODS: In total, 212 patients who passed or failed DQA measurements were retrospectively included in this study. Brain (n = 43), head and neck (n = 37), spinal (n = 12), prostate (n = 36), rectal (n = 36), pelvis (n = 13), cranial spinal irradiation and a treatment field i

Purpose: Various deformable image registration (DIR) methods have been used to evaluate organ deformations in 4-dimensional computed tomography (4D CT) images scanned during the respiratory motions of a patient. This study assesses the performance of 10 DIR algorithms using 4D CT images of 5 patients with fiducial markers (FMs) implanted during the postoperative radiosurgery of multiple lung metastases. Methods: To evaluate DIR algorithms, 4D CT images of 5 patients were used, and ground-truths