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Clinical Neuroradiology Sep 2023In 1971, the first computed tomography (CT) scan was performed on a patient's brain. Clinical CT systems were introduced in 1974 and dedicated to head imaging only. New... (Review)
Review
In 1971, the first computed tomography (CT) scan was performed on a patient's brain. Clinical CT systems were introduced in 1974 and dedicated to head imaging only. New technological developments, broader availability, and the clinical success of CT led to a steady growth in examination numbers. Most frequent indications for non-contrast CT (NCCT) of the head include the assessment of ischemia and stroke, intracranial hemorrhage and trauma, while CT angiography (CTA) has become the standard for first-line cerebrovascular evaluation; however, resulting improvements in patient management and clinical outcomes come at the cost of radiation exposure, increasing the risk for secondary morbidity. Therefore, radiation dose optimization should always be part of technical advancements in CT imaging but how can the dose be optimized? What dose reduction can be achieved without compromising diagnostic value, and what is the potential of the upcoming technologies artificial intelligence and photon counting CT? In this article, we look for answers to these questions by reviewing dose reduction techniques with respect to the major clinical indications of NCCT and CTA of the head, including a brief perspective on what to expect from current and future developments in CT technology with respect to radiation dose optimization.
Topics: Humans; Artificial Intelligence; Radiation Dosage; Tomography, X-Ray Computed; Computed Tomography Angiography; Angiography; Radiographic Image Interpretation, Computer-Assisted
PubMed: 36862232
DOI: 10.1007/s00062-023-01271-5 -
Anticancer Research Oct 2017To evaluate the efficacy of topical corticosteroids in managing acute radiation dermatitis (RD) in female breast cancer patients. (Meta-Analysis)
Meta-Analysis Review
AIM
To evaluate the efficacy of topical corticosteroids in managing acute radiation dermatitis (RD) in female breast cancer patients.
MATERIALS AND METHODS
MEDLINE, EMBASE, CINAHL, CENTRAL, ScienceDirect, Google Scholar and Clinicaltrials.gov were searched up to and including March 2017 to identify Randomised Controlled Trials (RCTs) assessing topical corticosteroids for the management and prevention of acute RD.
RESULTS
Ten RCTs (919 participants) were identified. Meta-analysis, including results for 845 participants, demonstrated significant benefits of topical corticosteroids in preventing the incidence of wet desquamation (OR: 0.29; 95%CI: 0.19-0.45; p<0.0001) and reducing the mean RD score (SMD: -0.47, 95%CI: -0.61 - -0.33, p<0.00001).
CONCLUSION
Topical corticosteroids impacted on the incidence of wet desquamation and the average RD score observed in female breast cancer patients. The use of topical corticosteroids can reduce pruritus in participants and improve quality of life.
Topics: Administration, Cutaneous; Adrenal Cortex Hormones; Breast Neoplasms; Chi-Square Distribution; Dermatologic Agents; Female; Humans; Odds Ratio; Quality of Life; Radiodermatitis; Radiotherapy, Adjuvant; Risk Factors; Treatment Outcome
PubMed: 28982842
DOI: 10.21873/anticanres.11960 -
European Journal of Epidemiology Dec 20172016 marked the 30th anniversary of the Chernobyl Nuclear Power Plant accident. We and others wrote reviews for the 25th anniversary. Since then, additional papers have... (Review)
Review
2016 marked the 30th anniversary of the Chernobyl Nuclear Power Plant accident. We and others wrote reviews for the 25th anniversary. Since then, additional papers have appeared and it seems timely to highlight lessons learned. To present, not a systematic review, but a commentary drawing attention to notable findings. We include not only recent reports and updates on previous results, but key findings from prior Chernobyl studies. The dose-dependent increase in Papillary Thyroid Cancer (PTC) following childhood I-131 exposure in Ukraine and Belarus has now been shown to persist for decades. Studies of post-Chernobyl PTCs have produced novel information on chromosomal rearrangements and gene fusions, critical to understanding molecular mechanisms. Studies of clean-up workers/liquidators suggest dose-related increases of thyroid cancer and hematological malignancies in adults. They also report increases in cardiovascular and cerebrovascular disease. If confirmed, these would have significant public health and radiation protection implications. The lens opacities following low to moderate doses found earlier are also a concern, particularly among interventional radiologists who may receive substantial lens doses. Finally, there is some, inconsistent, evidence for genetic effects among offspring of exposed persons. Further efforts, including improved dosimetry, collection of information on other risk factors, and continued follow-up/monitoring of established cohorts, could contribute importantly to further understand effects of low doses and dose-rates of radiation, particularly in young people, and ensure that appropriate public health and radiation protection systems are in place. This will require multinational collaborations and long-term funding.
Topics: Carcinoma, Papillary; Cardiovascular Diseases; Cataract; Chernobyl Nuclear Accident; Dose-Response Relationship, Radiation; Humans; Leukemia; Neoplasms, Radiation-Induced; Radiation Exposure; Radiation Injuries; Thyroid Cancer, Papillary; Thyroid Neoplasms
PubMed: 28929329
DOI: 10.1007/s10654-017-0303-6 -
Journal of Vascular Surgery Sep 2015Endovascular aortic repair has become increasingly popular the last years for the treatment of abdominal aortic aneurysms (EVAR) and thoracic aortic aneurysms. EVAR is... (Review)
Review
BACKGROUND
Endovascular aortic repair has become increasingly popular the last years for the treatment of abdominal aortic aneurysms (EVAR) and thoracic aortic aneurysms. EVAR is less invasive compared with the classic open approach, related to a decreased immediate postoperative morbidity and mortality. Those beneficial characteristics of EVAR do not come without a cost, since EVAR requires that the patient will be exposed to a significant amount of radiation during preoperative planning, graft placement, and consecutive follow-up. This systematic review examines the periprocedural radiation exposure to patients and staff as well as ways to ameliorate it.
METHODS
A systematic literature search was conducted using the MEDLINE electronic database. All articles reporting radiation exposure to alive humans during EVAR were eligible for review. Only studies publishing numerical data regarding radiation exposure were included in the Results section. Other relevant articles were used for further discussion.
RESULTS
Twenty-four studies, both prospective and retrospective in nature, were included. These studies revealed that the radiation exposure depends on the specific type of procedure, with more complex procedures carrying greater radiation burden. Variations in the positioning and operating of the fluoroscopic unit may significantly alter radiation dose to both patients and staff. There was an apparent lack of education among vascular specialists and trainees in terms of radiation safety awareness. At follow-up, a significant number of patients needed additional procedures, and all required radiographic imaging, further increasing the radiation exposure to alarming levels.
CONCLUSIONS
Every effort should be made to decrease radiation exposure related to endovascular aortic procedures. Attempts must be directed towards maximizing the operator's awareness, welcoming new imaging technology emitting less radiation, and shifting to follow-up strategies that require minimal or no radiation.
Topics: Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Aortography; Endovascular Procedures; Humans; Occupational Exposure; Radiation Dosage; Radiation Injuries; Radiation Monitoring; Radiation Protection; Radiography, Interventional; Risk Assessment; Risk Factors
PubMed: 26169014
DOI: 10.1016/j.jvs.2015.05.033 -
Journal of Medical Imaging and... Dec 2020Low-dose radiation exposure to Canadians is exponentially increasing due to the influx of diagnostic imaging and medical procedures that utilize radiation. Despite the... (Meta-Analysis)
Meta-Analysis
Eliminating the stigma: A systematic review of the health effects of low-dose radiation within the diagnostic imaging department and its implications for the future of medical radiation.
BACKGROUND
Low-dose radiation exposure to Canadians is exponentially increasing due to the influx of diagnostic imaging and medical procedures that utilize radiation. Despite the use of medical radiation since 1896, the standardized acceptable dose for the Canadian public is still debated. The current annual dose limit for the public is set at 1 millisievert (mSv). This set dose limit intrinsically restricts the use of medical radiation for diagnosis due to concerns of public health.
METHODS
This systematic review is in the form of a retrospective meta-analysis of previous experimental studies and observational reviews of low-dose radiation health effects. A database search using PubMed and Medscape identified 1,296 articles using the terms "low-dose radiation", "radiation hormesis", "radiation safety", "dose exposure", and "medical radiation". Full text articles were excluded for the following reasons: radiation dose level not <100mSv, results of radiation effects not included, or no inclusion of biologic effects on living tissue. After screening, 15 studies were selected for inclusion.
RESULTS
The concerns of radiation exposure are based on epidemiological and experimental studies that have indicated that high-dose ionizing radiation has toxic effects and increases cancer risk. In contrast, low-dose radiation has experimentally demonstrated various beneficial effects through a combination of molecular and cohort studies, randomized control trials, and observational analysis. The limitation of radiation in medical imaging is founded on the assumption that low-dose radiation health risks are a linear extrapolation of high-dose radiation.
DISCUSSION/CONCLUSIONS
Through a systematic review of research, it is proposed that the current dose-response extrapolation for radiation-related health risks cannot be linearly based on the effects at high doses. By altering this knowledge, we could effectively improve patient diagnosis and public health by redefining the restrictions of current radiation limits within diagnostic imaging.
Topics: Canada; Diagnostic Imaging; Humans; Radiation Dosage; Radiation Exposure; Radiation Injuries; Radiation Protection; Stereotyping
PubMed: 33342484
DOI: 10.1016/j.jmir.2020.07.052 -
Health Physics Mar 2019Well-characterized animal models that mimic the human response to potentially lethal doses of radiation are required to assess the efficacy of medical countermeasures...
The Gastrointestinal Subsyndrome of the Acute Radiation Syndrome in Rhesus Macaques: A Systematic Review of the Lethal Dose-response Relationship With and Without Medical Management.
Well-characterized animal models that mimic the human response to potentially lethal doses of radiation are required to assess the efficacy of medical countermeasures under the criteria of the US Food and Drug Administration's Animal Rule. Development of a model for the gastrointestinal acute radiation syndrome requires knowledge of the radiation dose-response relationship and time course of mortality and morbidity across the acute and prolonged gastrointestinal radiation syndrome. The nonhuman primate, rhesus macaque, is a relevant animal model that has been used to determine the efficacy of medical countermeasures to mitigate major signs of morbidity and mortality relative to the hematopoietic acute radiation syndrome, gastrointestinal acute radiation syndrome, and lung injury. It can be used to assess the natural history of gastrointestinal damage, concurrent multiple organ injury, and aspects of the mechanism of action for acute radiation exposure and treatment. A systematic review of relevant studies that determined the dose-response relationship for the gastrointestinal acute and prolonged radiation syndrome in the rhesus macaque relative to radiation dose, quality, dose rate, exposure uniformity, and use of medical management has never been performed.
Topics: Acute Radiation Syndrome; Animals; Dose-Response Relationship, Radiation; Gastrointestinal Diseases; Gastrointestinal Tract; Macaca mulatta
PubMed: 30624353
DOI: 10.1097/HP.0000000000000903 -
Dysphagia Feb 2021Videofluoroscopic swallowing study (VFSS) is generally used to diagnose dysphagia and oropharyngeal aspiration during swallowing movement. Patients and bolus-feeding...
Videofluoroscopic swallowing study (VFSS) is generally used to diagnose dysphagia and oropharyngeal aspiration during swallowing movement. Patients and bolus-feeding operators (such as occupational therapist and speech language pathologist) may undergo multiple VFSS procedure, placing them at risk for more radiation exposure due to increased scan time. The present study investigated the dose-area product, effective dose of various protocols, and summarized dose reports from various studies of VFSS. The PubMed database searched for relevant publications reporting radiation dose in the VFSS procedure. 13 articles were selected to be reviewed. This systematic review involved 13 peer-reviewed articles that reported the specific dose of the VFSS procedure. The articles were categorized into three types: operator radiation dose, adult patient radiation dose, and pediatric radiation dose. The operator dose reports showed that the operators' scattering exposure, equivalent dose (across the whole body, eyes, and hands), and annual effective dose were significantly lower than the annual dose limit of 20 mSv. Both adult and pediatric patient dose reports showed that the effective dose, which was estimated from recorded dose-area product, was significantly lower than the annual background exposure of 2.4 mSv in various protocols. The present literature review suggested that the radiation dose of VFSS by modified barium swallowing is acceptable in both operators and patients. However, various radiation protection strategies should be conducted during the procedure to reduce the risk of stochastic effect.
Topics: Adult; Child; Deglutition; Deglutition Disorders; Fluoroscopy; Humans; Radiation Dosage; Radiation Exposure
PubMed: 32279120
DOI: 10.1007/s00455-020-10112-3 -
Head & Neck Nov 2013Patients receiving radiotherapy (RT) for head and neck tumors are at risk of developing sensorineural hearing loss. The objective of this study was to analyze the... (Review)
Review
BACKGROUND
Patients receiving radiotherapy (RT) for head and neck tumors are at risk of developing sensorineural hearing loss. The objective of this study was to analyze the literature regarding sensorineural hearing loss after RT for head and neck cancer.
METHODS
Seven databases were searched to identify eligible studies. Eligible articles were independently assessed for quality by 2 authors.
RESULTS
Fourteen articles were evaluated. There was considerable heterogeneity among studies. The reported incidence of sensorineural hearing loss (SNHL) varied from 0% to 85% for the speech frequencies and from 27% to 95% for high frequencies. As the follow-up increased, an increase in the incidence of SNHL was observed. The minimum cochlear dose reported to be a risk factor for SNHL was 45 Gy.
CONCLUSIONS
High quality literature in the topic is lacking. Radiation-induced SNHL is progressive, permanent, and dose-dependent. Total dose and follow-up time are important factors affecting incidence rates.
Topics: Cohort Studies; Dose-Response Relationship, Radiation; Female; Follow-Up Studies; Head and Neck Neoplasms; Hearing Loss, Sensorineural; Humans; Male; Radiation Injuries; Radiotherapy Dosage; Radiotherapy, Conformal; Radiotherapy, Intensity-Modulated; Retrospective Studies; Risk Assessment; Time Factors; Treatment Outcome
PubMed: 23280686
DOI: 10.1002/hed.23201 -
Critical Reviews in Oncology/hematology Nov 2021Re-irradiation (re-RT) is a treatment modality that has been actively investigated in recurrent lung cancer or in lung metastases appeared in previously irradiated... (Meta-Analysis)
Meta-Analysis Review
Thoracic re-irradiation with 3D-conformal or more advanced techniques: A systematic review of treatment safety by the Re-irradiation Study Group of the Italian Association of Radiation and Oncology AIRO.
Re-irradiation (re-RT) is a treatment modality that has been actively investigated in recurrent lung cancer or in lung metastases appeared in previously irradiated areas. A literature search, according PRISMA recommendations and a meta-analysis technique were performed with the aims to identify possible factors related to the toxicity incidence and severity of ≥ G3 acute toxicity. 1243 patients and 36 studies, met inclusion criteria. Our results, showed that there was no difference in ≥ G3 acute (10,5%) toxicity rate with respect to different radiation techniques, cumulative dose and re-irradiation total dose and fractionation. Factors eventually related to severe toxicity were described. The frequent lack of a sufficient description of the treatment's intent, the heterogeneity in technique and radiotherapy regimen, makes balancing risk and benefit of re-RT based on published data even more difficult.
Topics: Dose Fractionation, Radiation; Humans; Italy; Neoplasm Recurrence, Local; Radiotherapy Dosage; Re-Irradiation
PubMed: 34688894
DOI: 10.1016/j.critrevonc.2021.103500 -
Clinical Neuroradiology Jun 2023The introduction of the first whole-body CT scanner in 1974 marked the beginning of cross-sectional spine imaging. In the last decades, the technological advancement,... (Review)
Review
The introduction of the first whole-body CT scanner in 1974 marked the beginning of cross-sectional spine imaging. In the last decades, the technological advancement, increasing availability and clinical success of CT led to a rapidly growing number of CT examinations, also of the spine. After initially being primarily used for trauma evaluation, new indications continued to emerge, such as assessment of vertebral fractures or degenerative spine disease, preoperative and postoperative evaluation, or CT-guided interventions at the spine; however, improvements in patient management and clinical outcomes come along with higher radiation exposure, which increases the risk for secondary malignancies. Therefore, technical developments in CT acquisition and reconstruction must always include efforts to reduce the radiation dose. But how exactly can the dose be reduced? What amount of dose reduction can be achieved without compromising the clinical value of spinal CT examinations and what can be expected from the rising stars in CT technology: artificial intelligence and photon counting CT? In this article, we try to answer these questions by systematically reviewing dose reduction techniques with respect to the major clinical indications of spinal CT. Furthermore, we take a concise look on the dose reduction potential of future developments in CT hardware and software.
Topics: Humans; Artificial Intelligence; Cross-Sectional Studies; Radiation Dosage; Tomography, X-Ray Computed; Spine
PubMed: 36416936
DOI: 10.1007/s00062-022-01227-1