tomotherapy

BACKGROUND/AIM: Interfractional anatomical variations cause considerable differences between planned and actual radiotherapy doses. This study aimed to investigate the efficacy of robust and planning target volume (PTV) margin-based optimizations for the anatomical variations in helical tomotherapy for prostate cancer. PATIENTS AND METHODS: Ten patients underwent treatment-planning kilovolt computed tomography (kVCT) and daily megavolt computed tomography (MVCT)...

BACKGROUND AND PURPOSE: TomoEDGE is an advanced technology for TomoTherapy treatment delivery by introducing a sliding-window dynamic jaw motion. The front and back jaws move independently at the start and end of a target volume along the longitudinal couch direction to reduce the undesired dose to the normal tissues. The accuracy of field width is essential to treatment delivery in this regard. The purpose of this work was to analyze the performance of dynamic jaws on helical tomotherapy and investigate the relationship with energy variation...

BACKGROUND: Inadequate computed tomography (CT) number calibration curves affect dose calculation accuracy. Although CT number calibration curves registered in treatment planning systems (TPSs) should be consistent with human tissues, it is unclear whether adequate CT number calibration is performed because CT number calibration curves have not been assessed for various types of CT number calibration phantoms and TPSs. PURPOSE: The purpose of this study was to investigate CT number calibration curves for mass density (ρ) and relative electron density (ρe )...

This study provides a concise and structured overview of a dosimetric comparison study conducted to assess the feasibility and effectiveness of 4 advanced radiotherapy techniques in treating brain metastases with hippocampus sparing and simultaneous integrated boost (HS-WBRT+SIB). Eleven patients with brain metastases previously treated with radiotherapy were included in the study. Planning CT scans with 2 mm slice thickness and MR imaging were used for contouring and dose prescription. The bilateral hippocampus and other organs at risk (OARs) were automatically contoured, and hippocampal avoidance regions (HAR) were defined as a 7 mm 3D expansion around the hippocampus...

BACKGROUND: Daily IGRT images show day-to-day anatomical variations in patients undergoing fractionated prostate radiotherapy. This is of particular importance in particle beam treatments. PURPOSE: To develop a digital phantom series showing variation in pelvic anatomy for evaluating treatment planning and IGRT procedures in particle radiotherapy. METHODS: A pelvic phantom series was developed from the planning MRI and kVCT (planning CT) images along with six of the daily serial MVCT images taken of a single patient treated with a full bladder on a Tomotherapy unit...

BACKGROUND: Studies comparing different radiotherapy treatment techniques-such as volumetric modulated arc therapy (VMAT) and helical tomotherapy (HT)-typically compare one treatment plan per technique. Often, some dose metrics favor one plan and others favor the other, so the final plan decision involves subjective preferences. Pareto front comparisons provide a more objective framework for comparing different treatment techniques. A Pareto front is the set of all treatment plans where improvement in one criterion is possible only by worsening another criterion...

BACKGROUND: Using adaptive radiotherapy (ART), to determine objective clinical criteria that identify extremity soft tissue sarcoma (ESTS) patients requiring adaptation of their preoperative radiotherapy (RT) plan. PATIENTS AND METHODS: We included 17 patients with a lower extremity ESTS treated between 2019 and 2021 with preoperative RT, using helicoidal intensity-modulated RT (IMRT) tomotherapy, before surgical resection. We collected clinical, tumor parameters and treatment data...

OBJECTIVE: This study aimed to discuss the dosimetric advantages of helical tomotherapy (HT) and volumetric modulated arc therapy (VMAT) technology in hippocampal avoidance whole-brain radiotherapy and provide references for clinical selection of ideal radiotherapy technology. METHODS: A total of 20 patients with hippocampal avoidance whole-brain radiotherapy were chosen randomly. Computed tomography (CT) and MRI scanning images were input into the treatment planning system (TPS)...

PURPOSE: To assess the value of radiation therapy (RT) with helical tomotherapy (HT) in the management of locally advanced malignant pleural mesothelioma (MPM) receiving no or lung-sparing surgery. METHODS: Consecutive MPM cases not undergoing extrapleural pneumonectomy and receiving intensity-modulated (IM) HT were retrospectively evaluated for local control, distant control, progression-free survival (PFS), and overall survival (OS). Impact of age, systemic treatment, RT dose, and recurrence patterns was analyzed by univariate and multivariate analysis...

In recent years Radiotherapy linear accelerator (linac) vendors have developed their own integrated quality control (QC) systems. Such Manufacturer-Integrated-Quality-Control (MIQC) has the potential to improve both the quality and efficiency of linac QC but is currently being developed and utilised in the absence of specific best-practice guidance. An Institute of Physics and Engineering in Medicine working party was commissioned with a view to develop guidance for the commissioning and implementation of MIQC...

AIMS: Low skeletal muscle mass index (SMI) has recently emerged as an independent prognostic factor in oncological patients and it is linked with poor survival and higher treatment toxicity. The present study aims to determine the possible impact of low SMI on survival and acute toxicity in oropharyngeal patients. METHODS: Seventy-six patients with locally advanced oropharyngeal squamous cell carcinoma (stage III-IVC) were treated in our institution with Helical TomoTherapy® (HT - Accuray, Maddison, WI, USA) between 2005 and 2021...

High doses of radiation to the hippocampus have been correlated with increased cognitive decline following radiation therapy for brain metastases. To mitigate these effects, a variety of hippocampal sparing techniques have been implemented for both whole brain radiation therapy (WBRT) and stereotactic radiosurgery (SRS). The goal of this review article is to provide a practical resource for the clinical implementation of hippocampal-sparing radiation therapy, starting with a brief background on the function and delineation of the hippocampal structure, as well as radiation effects on the hippocampus and the most widely recommended dose constraints...

AIM: Cardiac damage caused by radiation in the long term varies according to the radiation dose received by the heart. In this study, it was aimed to evaluate the damage caused by different radiation doses in the heart, together with hemodynamic parameters, immunhistochemistry, and histopathological analyzes for long term. METHOD AND MATERIALS: The animals were divided into four groups: The rats in control group (Group 1) were not irradiated; the rats in group 2 were irradiated with 5 Gy; the rats in group 3 were irradiated with 10 Gy and the rats in group 4 were irradiated with 20 Gy...

BACKGROUND: Intensity-modulated radiation therapy (IMRT) requires delivery quality assurance (DQA) to ensure treatment accuracy and safety. Irradiation techniques such as helical tomotherapy (HT) have become increasingly complex, rendering conventional verification methods insufficient. This study aims to develop a novel DQA system to simultaneously verify dose distribution and multi-leaf collimator (MLC) opening during HT. METHODS: We developed a prototype detector consisting of a cylindrical plastic scintillator (PS) and a cooled charge-coupled device (CCD) camera...

OBJECTIVE: The purpose of this scoping review was to explore the top 100 most cited articles in helical tomotherapy (HT) through bibliometric analysis and visualization tools, help researchers comprehensively understand the research hotspots of HT, and provide clear and intuitive network visualization. METHODS: The Web of Science Core Collection and the search strategy of "Title (TI)=(tomotherapy)" were used to search for articles related to HT as of 27 May 2023...

BACKGROUND/AIM: To compare heart, left ventricle (LV) and coronary artery dose-sparing with three-dimensional conformal radiotherapy (3D-CRT) vs. helical tomotherapy (HT) in left-sided breast cancer (BC). PATIENTS AND METHODS: 3D-CRT and HT treatments were planned for 20 patients (pts). Computed tomography (CT) scans without and with intravenous contrast (ic) were performed and co-registered. Left breast and organs at risk (OARs) were contoured. Dose-volume histograms (DVHs) for 3D-CRT and HT treatment plans were evaluated in terms of planning target volume for evaluation (PTVeval) coverage and dose to the OARs...

BACKGROUND: This study aimed to evaluate an a-priori multicriteria plan optimization algorithm (mCycle) for locally advanced breast cancer radiation therapy (RT) by comparing automatically generated VMAT (Volumetric Modulated Arc Therapy) plans (AP-VMAT) with manual clinical Helical Tomotherapy (HT) plans. METHODS: The study included 25 patients who received postoperative RT using HT. The patient cohort had diverse target selections, including both left and right breast/chest wall (CW) and III-IV node, with or without internal mammary node (IMN) and Simultaneous Integrated Boost (SIB)...

Orbital meningioma is a rare type of orbital tumor with high invasiveness and recurrence rates, making it extremely challenging to treat. Due to the special location of the disease, surgery often cannot completely remove the tumor, requiring postoperative radiation therapy. Here, we report a case of an elderly male patient with right-sided proptosis, visual impairment, and diplopia. Imaging diagnosis revealed a space-occupying lesion in the extraconal space of the right orbit. Pathological and immunohistochemical examination of the resected tumor confirmed it as a grade 3 anaplastic meningioma...

Neoadjuvant chemotherapy, when combined with radiotherapy, serves as an optional treatment for patients with locally advanced sigmoid colon cancer and is usually performed in conjunction with complete mesocolic excision. The substantial movement of surrounding organs in cases of sigmoid colon cancer frequently leads to toxicity in normal tissues. The present report details the case of a 76-year-old man diagnosed with locally advanced sigmoid colon cancer. Initially, treatment using the Tomotherapy Hi-Art system was selected; however, during image guidance from the first to the sixth fractions, the tumor location underwent a marked change, exceeding the range of the planning target volume...

This study presents a new treatment planning approach merging 3D-CRT and VMAT fields into a hybrid treatment plan (HybTP), in order to achieve an optimum dose coverage of the planning target volume (PTV) and protection of OAR. Craniospinal axis irradiation (CSI) treated with 3D conformal radiotherapy (3D-CRT) is associated with high doses to the heart and eye lenses but provides better sparing of lungs and kidneys compared to volumetric modulated arc therapy (VMAT). VMAT treatment spares eye lenses and the heart, but lungs and kidneys are not as effective as 3D-CRT...