Seonghee Kang

The prognostic role of aberrant serum miRNA expression for predicting response to sorafenib treatment in advanced hepatocellular carcinoma (HCC) patients has not been well characterized. We aimed to identify specific serum miRNAs that are associated with positive radiologic responses or improved survival in sorafenib-treated HCC patients. miR-18a, miR-21, miR-139-5p, miR-221, miR-224, and miR-10b-3p, were selected for analysis. Serum samples from 24 patients with advanced stage HCC and 25 patien

This study aims to analyze dose distribution and treatment time of endobronchial brachytherapy (EBBT) by changing the position step size of the dwell position. A solid water phantom and an intraluminal catheter were used in the treatment plan. The treatment plans were generated for 3, 5, 7, and 10 cm treatment lengths, respectively. For each treatment length, the source position step sizes were set as 2.5, 5, and 10 mm. Three reference points were set 1 cm away from the central axis of the cathe

This study is to assess the clinical use of commercial PerFRACTION™ for patient-specific quality assurance of volumetricmodulated arc therapy. Forty-six pretreatment verification plans for patients treated using a TrueBeam STx linear accelerator for lesions in various treatment sites such as brain, head and neck (H&N), prostate, and lung were included in this study. All pretreatment verification plans were generated using the Eclipse treatment planning system (TPS). Dose distributions obtained f

Purpose: This study aims to provide a direct, head-to-head comparison of treatment head leakage across seven modern clinical linear accelerators (linacs; Varian VitalBeam, TrueBeam STx, and Halcyon as well as Elekta Harmony Pro) measured under a consistent protocol. It characterizes the effects of machine architecture, manufacturer, and photon energy on the treatment head leakage profile. Methods: Gafchromic EBT4 films were calibrated and placed at 16 (C-arm) or 17 (ring-gantry) treatment head s

Purpose: Conventional gonadal shields are manufactured in standardized sizes and shapes and do not conform to individual testicular contours, causing discomfort. We developed a novel patientspecific gonadal shield using thermoplastic sheets and tested its feasibility through dosimetric evaluations. Methods: During the computed tomography simulation, custom lead shields were fabricated using thermoplastic sheets that were molded to the testicular shape of the patient. The shielding efficacy was e

Purpose: This study evaluated various methods for determining the half-value layer (HVL) of kilovoltage (kV) beams produced by the Varian TrueBeam STx on-board imager. By comparing these methods with the standard ionization chamber approach, the study aimed to identify practical solutions for HVL determination and dosimetric characterization of kV beams, particularly in resource-limited settings. Methods: HVLs for kV beams (40–140 kVp) were measured using an Exradin A12 ionization chamber and a

This study compared the dose calculated using the electron Monte Carlo (eMC) dose calculation algorithm employing the old version (eMC V13.7) of the Varian Eclipse treatment-planning system (TPS) and its newer version (eMC V16.1). The eMC V16.1 was configured using the same beam data as the eMC V13.7. Beam data measured using the VitalBeam linear accelerator were implemented. A box-shaped water phantom (30×30×30 cm3) was generated in the TPS. Consequently, the TPS with eMC V13.7 and eMC V16.1 ca

Purpose: This study aimed to develop a deep learning architecture combining two task models to generate synthetic computed tomography (sCT) images from low-tesla magnetic resonance (MR) images to improve metallic marker visibility. Methods: Twenty-three patients with cervical cancer treated with intracavitary radiotherapy (ICR) were retrospectively enrolled, and images were acquired using both a computed tomography (CT) scanner and a low-tesla MR machine. The CT images were aligned to the corres

Purpose: This study investigated the dose perturbation according to the size of the sensitive volume in the dosimeter in small-field dosimetry. Methods: The dose profiles with different field sizes were measured using three different dosimeters: the CC13, Razor ion chamber, and Edge solid-state detector. Both the open and wedged beams with different field sizes were employed in the measurement. The profiles were measured in a water phantom at maximum dose depths of 5, 10, and 20 cm. The penumbra

Herein, we provide a concise review of the critical role of motion management in radiation therapy, with a focus on photon radiation therapy, real-time control of respiratory motion, and image-guided radiation therapy (IGRT) in lung stereotactic body radiation therapy (SBRT). The dynamic nature of human anatomy, particularly in regions prone to movement such as the thoracic and abdominal areas, poses significant challenges in accurately targeting tumors during radiation therapy. This review expl

Purpose This study aimed to compare treatment outcomes and toxicity profile between imaged-guided brachytherapy (IGBT) versus conventional brachytherapy (CBT) performed by the same practitioner during the same time period.Materials and Methods Medical records of 104 eligible patients who underwent brachytherapy for locally advanced cervical cancer were retrospectively reviewed. Fifty patients (48.1%) underwent IGBT, and 54 (51.9%) patients underwent CBT. All patients underwent concurrent chemora

Purpose: This study evaluated the features of a pressure mapping system for patient motion monitoring in radiation therapy. Methods: The pressure mapping system includes an MS 9802 force sensing resistor (FSR) sensor with 2,304 force sensing nodes using 48 columns and 48 rows, controller, and control PC (personal computer). Radiation beam attenuation caused by pressure mapping sensor and signal perturbation by 6 and 10 mega voltage (MV) photon beam was evaluated. The maximum relative pressure va

Purpose: Accurate operation of the multi-leaf collimator (MLC), a key technology in intensity modulated radiation therapy (IMRT), is essential for safe and optimal radiation treatment. The HalcyonTM linear accelerator has a collimator with low leakage and radiation transmission, making it suitable for IMRT. The limitations of the existing HalcyonTM MLC quality assurance (QA) method were supplemented with a mathematical method, and the results were analyzed. Methods: Electric portal imaging devic

Purpose: T his s tudy e valuated t he c linical f easibility a nd d osimetric a ccuracy o f a newly implemented ceiling-mounted spoiler (CMS) system for total body irradiation (TBI) and established beam parameters for extended source-to-surface distance (SSD) setups. Methods: The CMS consisted of modular acrylic panels (1.5 cm thick, 50×147 cm²) mounted on ceiling rails aligned with the treatment position, which was located 400 cm from the isocenter. Detachable magnetic sections enabled full-bod

Purpose: The enhanced leaf modeling (ELM) algorithm, introduced in Eclipse v18, includes rounded leaf tip geometry to enhance the accuracy of multi-leaf collimator (MLC) modeling. This study aimed to assess the clinical consistency of empirically optimized dosimetric leaf gap (DLG) and transmission parameters used in the previous version (v16) when applied to the upgraded ELM algorithm. Methods: The DLG and transmission values optimized in Eclipse v16 were re-evaluated using the ELM model in v18