ABSTRACT
Radiation?induced heart disease ( RIHD) is a common type of radiation?induced damages in chest radiotherapy. There are no obvious short?term symptoms in patients with RIHD. However, RIHD causes irreversible permanent damages to the heart over time, which undermines the quality of life. Patients with severe RIHD even have a risk of death from myocardial infarction caused by coronary atherosclerosis. This paper summarizes the research advances in epidemiology, diagnosis, mechanisms of radiation?induced injury in various parts of the heart, radiotherapy techniques, and treatment. Reduction in radiation range and dose, early diagnosis, and early treatment are recommended for patients to reduce heart injury and improve the quality of life.
ABSTRACT
The Medline and CNKI databases were searched with the key words of radiation-induced myocardial damage,damage pathway,pathogenesis,and intervention,and 37 articles were obtained.The pathogenesis of radiation-induced myocardial damage may be related to various mechanisms such as oxidative stress,transforming growth factor-β,renin-angiotensin system,mast cells,and endothelial dysfunction.The pathogenesis of radiation-induced myocardial damage is a complex process involving various mechanisms,and currently,there are ongoing studies on the cellular and molecular mechanisms involved in its pathogenesis and interventions.
ABSTRACT
Objective To explore the setup errors of two different position fixing techniques in radiotherapy for thoracic canc -er, and analyze and compare the accuracy and repeatability of the two different techniques .Methods Sixty four patients with thoracic cancer were selected in our hospital from December 2011 to June 2013 .All patients received radiotherapy .Patients were divided into two groups by means of random number table .Each group had 32 cases.The low-temperature thermoplastic membrane group used ther-moplastic membrane method to fix position while vacuum bag group with negative pressure fixed position by vacuum bag method .The setup errors in the right/left direction (X-axis), anterior/posterior direction (Z-axis), head/foot direction (Y-axis) and three dimen-sional directions ( I) were compared and analyzed between the two groups .Results The low-temperature thermoplastic membrane group was able to reduce the setup errors significantly in the Z-axis (1.13 ±0.33 /2.33 ±1.24, P 0.05).Conclusions Position fixing technique with low-temperature thermoplastic membrane can help to fix position in radiotherapy for thoracic cancer , reduce the setup errors in the Z-axis, and improve the setup accuracy .
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Objective To study the set-up accuracy in radiotherapy of thoracic neoplasms by improving the body immobilization method.Methods Fifty patients with thoracic neoplasms were randomly divided into conventional group (without electrode paste) and improved group (with electrode paste).Using simulator for position calibration and center field digital image reconstruction from treatment planning system.Then compare the set-up accuracy of two groups with different body methods by grouped t-test.Results Set-up error in the left-right,superior-inferior,anterior-posterior direction were 2.5 ± 1.5 and 2.4 ± 1.4(P =0.010),4.4 ± 2.0 and 2.2 ± 1.2 (P =0.000),2.2 ± 1.3 and 2.1 ± 1.0 (P =0.100) in conventional group and improved group,respectively.Conclusions The improved body immobilization method improves setup accuracy in radiotherapy for thoracic neoplasms which also will be effective for clinical treatment.
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Objective To assess the rotational set-up errors in patients with thoracic neoplasms. Methods 224 kilovohage cone-beam computed tomography (KVCBCT) scans from 20 thoracic tumor pa-tients were evaluated retrospectively. All these patients were involved in the research of " Evaluation of the residual set-up error for online kilovohage cone-beam CT guided thoracic tumor radiation". Rotational set-up errors, including pitch, roll and yaw, were calculated by 'aligning the KVCBCT with the planning CT, using the semi-automatic alignment method. Results The average rotational set-up errors were -0.28°±1.52°, 0.21°± 0.91° and 0.27°± 0. 78° in the left-fight, superior-inferior and anterior-posterior axis, respective-ly. The maximal rotational errors of pitch, roll and yaw were 3.5°, 2.7° and 2.2°, respectively. After cor-rection for translational set-up errors, no statistically significant changes in rotational error were observed. Conclusions The rotational set-up errors in patients with thoracic neoplasms were all small in magnitude. Rotational errors may not change after the correction for translational set-up errors alone, which should be e-valuated in a larger sample future.