This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
PurposeThis study aimed to assess the accuracy and dosimetric impact of the Acuros XB (AXB) algor... more PurposeThis study aimed to assess the accuracy and dosimetric impact of the Acuros XB (AXB) algorithm compared to the Anisotropic Analytical Algorithm (AAA) in two situations. First, simple phantom geometries were set and analyzed; moreover, volumetric modulated arc therapy (VMAT) clinical plans for Head & Neck and lung cases were calculated and compared.MethodsFirst, a phantom study was performed to compare the algorithms with radiochromic EBT3 film doses using one PMMA slab phantom and two others containing foam or air gap. Subsequently, a clinical study was conducted, including 20 Head & Neck and 15 lung cases irradiated with the VMAT technique. The treatment plans calculated by AXB and AAA were evaluated in terms of planning target volume (PTV) coverage (V95%), dose received by relevant organs at risk (OARs), and the impact of using AXB with a grid size of 1 mm. Finally, patient‐specific quality assurance (PSQA) was performed and compared for 17 treatment plans.ResultsPhantom do...
The aim of this study was to evaluate knowledge-based treatment planning (KBP) models in terms of... more The aim of this study was to evaluate knowledge-based treatment planning (KBP) models in terms of their dosimetry and deliverability and to investigate their clinical benefits. Three H&N KBP models were built utilizing RapidPlan™, based on the dose prescription, which is given according to the planning target volume (PTV). The training set for each model consisted of 43 clinically acceptable volumetric modulated arc therapy (VMAT) plans. Model quality was assessed and compared to the delivered treatment plans using the homogeneity index (HI), conformity index (CI), structure dose difference (PTV, organ at risk—OAR), monitor units, MU factor, and complexity index. Model deliverability was assessed through a patient-specific quality assurance (PSQA) gamma index-based analysis. The dosimetric assessment showed better OAR sparing for the RapidPlan™ plans and for the low- and high-risk PTV, and the HI, and CI were comparable between the clinical and RapidPlan™ plans, while for the interm...
Οι ακτίνες –Χ ανήκουν στις ιοντίζουσες ακτινοβολίες και ανακαλύφτηκαν από τον Röntgen to 1895. Στ... more Οι ακτίνες –Χ ανήκουν στις ιοντίζουσες ακτινοβολίες και ανακαλύφτηκαν από τον Röntgen to 1895. Στο ενεργειακό τους φάσμα διακρίνεται το συνεχές φάσμα που οφείλεται στην ακτινοβολία πεδήσεως και παρουσιάζει ένα μέγιστο που καθορίζεται από την επιλογή των kVp, και το γραμμικό, οι κορυφές του οποίου είναι χαρακτηριστικές του στοιχείου της ανόδου της λυχνίας. Κατά την αλληλεπίδραση των φωτονίων –Χ με την ύλη είναι πιθανά τα φαινόμενα: φωτοηλεκτρικό, Compton και δίδυμη γένεση. Για τις δέσμες που χρησιμοποιούνται στην Ακτινοδιαγνωστική, έως 150 keV, παρατηρούνται μόνο τα δύο πρώτα φαινόμενα, με τη φωτοηλεκτρική απορρόφηση να επικρατεί σε χαμηλές ενέργειες στα στοιχεία με υψηλό ατομικό αριθμό (οστά). Στην αναλογική ακτινογραφία η δέσμη ακτίνων –Χ, που παράγονται από τη λυχνία Coolidge, αφού αλληλεπιδράσουν με την προς εξέταση δομή προσπίπτουν στο φιλμ και σχηματίζουν την πρωτογενή ακτινολογική εικόνα. Η μορφή της εξαρτάται από την ατομική σύνθεση του υλικού, τα kVp, τα mAs και από τα φίλτρ...
The Coronavirus disease 2019 (COVID-19) pandemic continues to spread worldwide with over 260 mill... more The Coronavirus disease 2019 (COVID-19) pandemic continues to spread worldwide with over 260 million people infected and more than 5 million deaths, numbers that are escalating on a daily basis. Frontline health workers and scientists diligently fight to alleviate life-threatening symptoms and control the spread of the disease. There is an urgent need for better triage of patients, especially in third world countries, in order to decrease the pressure induced on healthcare facilities. In the struggle to treat life-threatening COVID-19 pneumonia, scientists have debated the clinical use of ionizing radiation (IR). The historical literature dating back to the 1940s contains many reports of successful treatment of pneumonia with IR. In this work, we critically review the literature for the use of IR for both diagnostic and treatment purposes. We identify details including the computed tomography (CT) scanning considerations, the radiobiological basis of IR anti-inflammatory effects, th...
Stereotactic ablative radiotherapy (SABR) is highly focused radiation therapy that targets well-d... more Stereotactic ablative radiotherapy (SABR) is highly focused radiation therapy that targets well-demarcated, limited-volume malignant or benign tumors with high accuracy and precision using image guidance. Stereotactic arrhythmia radioablation (STAR) applies SABR to treat cardiac arrhythmias, including ventricular tachycardia (VT) and atrial fibrillation (AF), and has recently been a focus in research. Clinical studies have demonstrated electrophysiologic conduction blockade and histologic fibrosis after STAR, which provides a proof of principle for its potential for treating arrhythmias. This review will present the basic STAR principles, available clinical study outcomes, and how the technique has evolved since the first pre-clinical study. In addition to the clinical workflow, focus will be given on the process for stereotactic radiotherapy Quality Assurance (QA) tests, as well as the need for establishing a standardized QA protocol. Future implications and potential courses of re...
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
PurposeThis study aimed to assess the accuracy and dosimetric impact of the Acuros XB (AXB) algor... more PurposeThis study aimed to assess the accuracy and dosimetric impact of the Acuros XB (AXB) algorithm compared to the Anisotropic Analytical Algorithm (AAA) in two situations. First, simple phantom geometries were set and analyzed; moreover, volumetric modulated arc therapy (VMAT) clinical plans for Head & Neck and lung cases were calculated and compared.MethodsFirst, a phantom study was performed to compare the algorithms with radiochromic EBT3 film doses using one PMMA slab phantom and two others containing foam or air gap. Subsequently, a clinical study was conducted, including 20 Head & Neck and 15 lung cases irradiated with the VMAT technique. The treatment plans calculated by AXB and AAA were evaluated in terms of planning target volume (PTV) coverage (V95%), dose received by relevant organs at risk (OARs), and the impact of using AXB with a grid size of 1 mm. Finally, patient‐specific quality assurance (PSQA) was performed and compared for 17 treatment plans.ResultsPhantom do...
The aim of this study was to evaluate knowledge-based treatment planning (KBP) models in terms of... more The aim of this study was to evaluate knowledge-based treatment planning (KBP) models in terms of their dosimetry and deliverability and to investigate their clinical benefits. Three H&N KBP models were built utilizing RapidPlan™, based on the dose prescription, which is given according to the planning target volume (PTV). The training set for each model consisted of 43 clinically acceptable volumetric modulated arc therapy (VMAT) plans. Model quality was assessed and compared to the delivered treatment plans using the homogeneity index (HI), conformity index (CI), structure dose difference (PTV, organ at risk—OAR), monitor units, MU factor, and complexity index. Model deliverability was assessed through a patient-specific quality assurance (PSQA) gamma index-based analysis. The dosimetric assessment showed better OAR sparing for the RapidPlan™ plans and for the low- and high-risk PTV, and the HI, and CI were comparable between the clinical and RapidPlan™ plans, while for the interm...
Οι ακτίνες –Χ ανήκουν στις ιοντίζουσες ακτινοβολίες και ανακαλύφτηκαν από τον Röntgen to 1895. Στ... more Οι ακτίνες –Χ ανήκουν στις ιοντίζουσες ακτινοβολίες και ανακαλύφτηκαν από τον Röntgen to 1895. Στο ενεργειακό τους φάσμα διακρίνεται το συνεχές φάσμα που οφείλεται στην ακτινοβολία πεδήσεως και παρουσιάζει ένα μέγιστο που καθορίζεται από την επιλογή των kVp, και το γραμμικό, οι κορυφές του οποίου είναι χαρακτηριστικές του στοιχείου της ανόδου της λυχνίας. Κατά την αλληλεπίδραση των φωτονίων –Χ με την ύλη είναι πιθανά τα φαινόμενα: φωτοηλεκτρικό, Compton και δίδυμη γένεση. Για τις δέσμες που χρησιμοποιούνται στην Ακτινοδιαγνωστική, έως 150 keV, παρατηρούνται μόνο τα δύο πρώτα φαινόμενα, με τη φωτοηλεκτρική απορρόφηση να επικρατεί σε χαμηλές ενέργειες στα στοιχεία με υψηλό ατομικό αριθμό (οστά). Στην αναλογική ακτινογραφία η δέσμη ακτίνων –Χ, που παράγονται από τη λυχνία Coolidge, αφού αλληλεπιδράσουν με την προς εξέταση δομή προσπίπτουν στο φιλμ και σχηματίζουν την πρωτογενή ακτινολογική εικόνα. Η μορφή της εξαρτάται από την ατομική σύνθεση του υλικού, τα kVp, τα mAs και από τα φίλτρ...
The Coronavirus disease 2019 (COVID-19) pandemic continues to spread worldwide with over 260 mill... more The Coronavirus disease 2019 (COVID-19) pandemic continues to spread worldwide with over 260 million people infected and more than 5 million deaths, numbers that are escalating on a daily basis. Frontline health workers and scientists diligently fight to alleviate life-threatening symptoms and control the spread of the disease. There is an urgent need for better triage of patients, especially in third world countries, in order to decrease the pressure induced on healthcare facilities. In the struggle to treat life-threatening COVID-19 pneumonia, scientists have debated the clinical use of ionizing radiation (IR). The historical literature dating back to the 1940s contains many reports of successful treatment of pneumonia with IR. In this work, we critically review the literature for the use of IR for both diagnostic and treatment purposes. We identify details including the computed tomography (CT) scanning considerations, the radiobiological basis of IR anti-inflammatory effects, th...
Stereotactic ablative radiotherapy (SABR) is highly focused radiation therapy that targets well-d... more Stereotactic ablative radiotherapy (SABR) is highly focused radiation therapy that targets well-demarcated, limited-volume malignant or benign tumors with high accuracy and precision using image guidance. Stereotactic arrhythmia radioablation (STAR) applies SABR to treat cardiac arrhythmias, including ventricular tachycardia (VT) and atrial fibrillation (AF), and has recently been a focus in research. Clinical studies have demonstrated electrophysiologic conduction blockade and histologic fibrosis after STAR, which provides a proof of principle for its potential for treating arrhythmias. This review will present the basic STAR principles, available clinical study outcomes, and how the technique has evolved since the first pre-clinical study. In addition to the clinical workflow, focus will be given on the process for stereotactic radiotherapy Quality Assurance (QA) tests, as well as the need for establishing a standardized QA protocol. Future implications and potential courses of re...
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