scholarly journals Navigation and non-navigation CT scan of the sinuses: comparison of the effective doses of radiation in children and adults

Author(s):  
Noémie Villemure-Poliquin ◽  
Mario Chrétien ◽  
Jacques E. Leclerc

Abstract Background The advent of 3D navigation imaging has opened new borders to the endoscopic surgical approaches of naso-sinusal inflammatory and neoplastic disease. This technology has gained in popularity among otolaryngologists for endoscopic sinus and skull base surgeries in both adults and children. However, the increased tissue radiation required for data acquisition associated with 3D navigation protocols CT scans is a source of concern because of its potential health hazards. We aimed to compare the effective doses of radiation between 3D navigation protocols and standard protocols for sinus computed tomography (CT) scans for both the adult and pediatric population. Methods We performed a retrospective cohort study through electronic chart review of patients undergoing sinus CT scans (standard and 3D navigation protocols) from May 2019 to December 2019 using a Siemens Drive (VA62A) CT scanner. The effective dose of radiation was calculated in mSv for all exams. Average irradiation doses were compared using a Student’s T-Test or a Kruskall–Wallis test when appropriate. Results A total of 115 CT scans were selected for analysis, of which 47 were standard protocols and 68 were 3D navigation protocols CT scans. Among these, 31 exams were performed on children and 84 exams on adults. For the total population, mean effective dose in the non-navigation CT scans was 0.37 mSv (SD: 0.16, N = 47) and mean effective dose in the 3D navigation sinus CT group was 2.33 mSv (SD: 0.45, N = 68). The mean difference between the two groups was statistically significant 1.97 mSv (CI 95% − 2.1 to − 1.83; P < 0.0001). There was a sixfold increase in radiation with utilization of 3D navigation protocols. The ratio was identical when the pediatric as well as the adult subset of patients were analyzed. Conclusion In our center, utilization of 3D navigation sinus CT protocols significantly increases radiation exposure. Otolaryngologists should be aware of this significant increase and should attempt to decrease the radiation exposure of their patients by limiting unnecessary scan orders and by evaluating 3D acquisition protocols locally with radiation physicists. Level of evidence: Level IV. Graphical Abstract

2019 ◽  
Vol 186 (2-3) ◽  
pp. 386-390
Author(s):  
V Dufek ◽  
H Zackova ◽  
L Kotik ◽  
I Horakova

Abstract About 26 000 patients are treated per year with radiotherapy for non-malignant diseases in the Czech Republic. Approximately 75% of them are treated on X-ray therapy units and most of these patients undergo radiotherapy of heel spurs. The evaluation of radiation exposure of these patients was based on measured organ doses and on data from clinical practice. Collective effective doses for particular diagnoses were calculated in order to compare doses resulting from different diagnoses treated on X-ray therapy units. The collective effective dose from radiotherapy of heel spurs in the Czech Republic in 2013 was evaluated to 77 manSv. It represents 25.6% of the total collective effective dose for all diagnoses of radiotherapy for non-malignant diseases treated on X-ray therapy units.


2020 ◽  
Vol 189 (4) ◽  
pp. 466-474
Author(s):  
Wiam Elshami ◽  
Mohamed Abuzaid ◽  
Antti Pekkarinen ◽  
Mika Kortesniemi

Abstract Purpose Occupational radiation exposure for medical workers in radiology and cardiology was analyzed in nine hospitals in the UAE between 2002 and 2016. The purpose of the study was to determine the time trend and the differences in occupational radiation exposure among worker groups and hospitals in the country. Methods Readings of 5700 thermoluminescence dosimeters (TLDs) were obtained from 1011 medical workers and grouped into 5 worker groups (radiographers, diagnostic radiologists, nurses, cardiologists and physicians). Results The mean annual effective dose was from 0.38 to 0.62 mSv per worker. Even though an increase in the collective effective dose has been noticed during the study period, no significant time trend was observed in the mean effective dose. Furthermore, cardiologists received higher mean and maximum effective doses than the other worker groups. Conclusion The annual effective doses were below the limits set by national legislation and international standards, and for the average worker, the likelihood of high exposure is small. However, improvements in radiation protection practices could be implemented to reduce occupational radiation dose to cardiologists, who were the most exposed worker group in this study.


2020 ◽  
Vol 65 (1) ◽  
pp. 13-16
Author(s):  
S. Somov

Purpose: Improving the quality of radiation assessment of patients of the medical institution of the dental profile using the calculated values of effective doses. Material and methods: Using the RED-2018 and ORTO-2018 programs, the values of effective patient exposure doses for 29 medical organizations of the dental profile were calculated. The obtained values of the effective dose were compared with the values specified in the methodological recommendations MP 0100 / 1659-07-26 of February 16, 2007 “Filling of forms of federal state statistical observation 3-DOZ”. Results: The analysis showed that the doses obtained using the RED-2018 and ORTO-2018 computer programs, respectively, are 21 and 14 times lower than the doses indicated in the methodological recommendations MP 0100 / 1659-07-26. Conclusion: It is shown that the developed computer programs can be applied by a dentist practicing physician who performs an x-ray examination in order to automatically and reliably determine the patient’s dose when performing x-ray-mathematical studies in accordance with the guidelines of MU 2.6.1.2944-11 “Monitoring effective doses of patients during x-ray examinations” also used in the preparation of radiation hygienic passports of organizations and statistical form 3-DOZ. The indication of the actually calculated values of the effective dose of the patient, rather than repeatedly overestimated averages, will reduce the level of radiophobia in society.


Author(s):  
J. Bazoma ◽  
G. B. Dallou ◽  
P. Ondo Meye ◽  
C. Bouka Biona ◽  
Saïdou ◽  
...  

The present study aimed at estimating organ and effective doses from computed tomography (CT) scans of paediatric patients in three hospitals in Brazzaville, Congo Republic. A total of 136 data on paediatric patients, from 0.25 (3 months) to 15 years old, who underwent head, chest, abdomen – pelvis (AP) and chest – abdomen – pelvis (CAP) CT scans was considered. The approach followed in the present study to compute organ doses was to use pre-calculated volume CT dose index (CTDIvol) – and 100 milliampere-second (mAs) – normalized organ doses determined by Monte Carlo (MC) simulation. Effective dose were then derived using the international commission on radiological protection (ICRP) publications 60 and 103 formalism. For comparison purposes, effective dose were also computed using dose-length product (DLP) – to – effective dose conversion factors. A relatively high variation in organ and effective doses was observed in each age group due to the dependence of patient dose on the practice of technicians who perform the CT scan within the same facility or from one facility to another, patient size and lack of adequate training of technicians. In the particular case of head scan, the brain and the eye lens were delivered maximum absorbed doses of 991.81 mGy and 1176.51 mGy, respectively (age group 10-15 y). The maximum absorbed dose determined for the red bone marrow was 246.08 mGy (age group 1-5 y). This is of concern as leukaemia and brain tumours are the most common childhood cancers and as the ICRP recommended absorbed dose threshold for induction of cataract is largely exceeded. Effective doses derived from MC calculations and ICRP publications 60 and 103 tissues weighting factors showed a 0.40-17.61 % difference while the difference between effective doses derived by the use of k- factors and those obtained by MC calculations ranges from 0.06 to 224.87 %. The study has shown that urgent steps should be taken in order to significantly reduce doses to paediatric patients to levels observed in countries where dose reduction techniques are successfully applied.


Biology ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 646
Author(s):  
Rosario Francesco Grasso ◽  
Flavio Andresciani ◽  
Carlo Altomare ◽  
Giuseppina Pacella ◽  
Gennaro Castiello ◽  
...  

(1) Background: The aim of this retrospective study is to assess safety and efficacy of lung radiofrequency (RFA) and microwave ablation (MWA) using an augmented reality computed tomography (CT) navigation system (SIRIO) and to compare it with the standard CT-guided technique. (2) Methods: Lung RFA and MWA were performed with an augmented reality CT 3D navigation system (SIRIO) in 52 patients. A comparison was then performed with a group of 49 patients undergoing the standard CT-guided technique. All the procedures were divided into four groups based on the lesion diameter (>2 cm or ≤2 cm), and procedural time, the number of CT scans, radiation dose administered, and complications rate were evaluated. Technical success was defined as the presence of a “ground glass” area completely covering the target lesion at the immediate post-procedural CT. (3) Results: Full technical success was achieved in all treated malignant lesions for all the considered groups. SIRIO-guided lung thermo-ablations (LTA) displayed a significant decrease in the number of CT scans, procedure time, and patients’ radiation exposure (p < 0.001). This also resulted in a dosage reduction in hypnotics and opioids administrated for sedation during LTA. No significant differences were observed between the SIRIO and non-SIRIO group in terms of complications incidence. (4) Conclusions: SIRIO is an efficient tool to perform CT-guided LTA, displaying a significant reduction (p < 0.001) in the number of required CT scans, procedure time, and patients’ radiation exposure.


2020 ◽  
Vol 33 (6) ◽  
pp. 838-844
Author(s):  
Jan-Helge Klingler ◽  
Ulrich Hubbe ◽  
Christoph Scholz ◽  
Florian Volz ◽  
Marc Hohenhaus ◽  
...  

OBJECTIVEIntraoperative 3D imaging and navigation is increasingly used for minimally invasive spine surgery. A novel, noninvasive patient tracker that is adhered as a mask on the skin for 3D navigation necessitates a larger intraoperative 3D image set for appropriate referencing. This enlarged 3D image data set can be acquired by a state-of-the-art 3D C-arm device that is equipped with a large flat-panel detector. However, the presumably associated higher radiation exposure to the patient has essentially not yet been investigated and is therefore the objective of this study.METHODSPatients were retrospectively included if a thoracolumbar 3D scan was performed intraoperatively between 2016 and 2019 using a 3D C-arm with a large 30 × 30–cm flat-panel detector (3D scan volume 4096 cm3) or a 3D C-arm with a smaller 20 × 20–cm flat-panel detector (3D scan volume 2097 cm3), and the dose area product was available for the 3D scan. Additionally, the fluoroscopy time and the number of fluoroscopic images per 3D scan, as well as the BMI of the patients, were recorded.RESULTSThe authors compared 62 intraoperative thoracolumbar 3D scans using the 3D C-arm with a large flat-panel detector and 12 3D scans using the 3D C-arm with a small flat-panel detector. Overall, the 3D C-arm with a large flat-panel detector required more fluoroscopic images per scan (mean 389.0 ± 8.4 vs 117.0 ± 4.6, p < 0.0001), leading to a significantly higher dose area product (mean 1028.6 ± 767.9 vs 457.1 ± 118.9 cGy × cm2, p = 0.0044).CONCLUSIONSThe novel, noninvasive patient tracker mask facilitates intraoperative 3D navigation while eliminating the need for an additional skin incision with detachment of the autochthonous muscles. However, the use of this patient tracker mask requires a larger intraoperative 3D image data set for accurate registration, resulting in a 2.25 times higher radiation exposure to the patient. The use of the patient tracker mask should thus be based on an individual decision, especially taking into considering the radiation exposure and extent of instrumentation.


2008 ◽  
Vol 47 (04) ◽  
pp. 175-177 ◽  
Author(s):  
J. Dolezal

SummaryAim: To assess a radiation exposure and the quality of radiation protection concerning a nuclear medicine staff at our department as a six-year retrospective study. Therapeutic radionuclides such as 131I, 153Sm, 186Re, 32P, 90Y and diagnostic ones as a 99mTc, 201Tl, 67Ga, 111In were used. Material, method: The effective dose was evaluated in the period of 2001–2006 for nuclear medicine physicians (n = 5), technologists (n = 9) and radiopharmacists (n = 2). A personnel film dosimeter and thermoluminescent ring dosimeter for measuring (1-month periods) the personal dose equivalent Hp(10) and Hp(0,07) were used by nuclear medicine workers. The wearing of dosimeters was obligatory within the framework of a nationwide service for personal dosimetry. The total administered activity of all radionuclides during these six years at our department was 17,779 GBq (99mTc 14 708 GBq, 131I 2490 GBq, others 581 GBq). The administered activity of 99mTc was similar, but the administered activity of 131I in 2006 increased by 200%, as compared with the year 2001. Results: The mean and one standard deviation (SD) of the personal annual effective dose (mSv) for nuclear medicine physicians was 1.9 ± 0.6, 1.8 ± 0.8, 1.2 ± 0.8, 1.4 ± 0.8, 1.3 ± 0.6, 0.8 ± 0.4 and for nuclear medicine technologists was 1.9 ± 0.8, 1.7 ± 1.4, 1.0 ± 1.0, 1.1 ± 1.2, 0.9 ± 0.4 and 0.7 ± 0.2 in 2001, 2002, 2003, 2004, 2005 and 2006, respectively. The mean (n = 2, estimate of SD makes little sense) of the personal annual effective dose (mSv) for radiopharmacists was 3.2, 1.8, 0.6, 1.3, 0.6 and 0.3. Although the administered activity of 131I increased, the mean personal effective dose per year decreased during the six years. Conclusion: In all three professional groups of nuclear medicine workers a decreasing radiation exposure was found, although the administered activity of 131I increased during this six-year period. Our observations suggest successful radiation protection measures at our department.


Author(s):  
Sebastian Zensen ◽  
Sumitha Selvaretnam ◽  
Marcel Opitz ◽  
Denise Bos ◽  
Johannes Haubold ◽  
...  

Abstract Purpose Apart from the commonly applied manual needle biopsy, CT-guided percutaneous biopsies of bone lesions can be performed with battery-powered drill biopsy systems. Due to assumably different radiation doses and procedural durations, the aim of this study is to examine radiation exposure and establish local diagnostic reference levels (DRLs) of CT-guided bone biopsies of different anatomical regions. Methods In this retrospective study, dose data of 187 patients who underwent CT-guided bone biopsy with a manual or powered drill biopsy system performed at one of three different multi-slice CT were analyzed. Between January 2012 and November 2019, a total of 27 femur (A), 74 ilium (B), 27 sacrum (C), 28 thoracic vertebrae (D) and 31 lumbar vertebrae (E) biopsies were included. Radiation exposure was reported for volume-weighted CT dose index (CTDIvol) and dose–length product (DLP). Results CTDIvol and DLP of manual versus powered drill biopsy were (median, IQR): A: 56.9(41.4–128.5)/66.7(37.6–76.2)mGy, 410(203–683)/303(128–403)mGy·cm, B: 83.5(62.1–128.5)/59.4(46.2–79.8)mGy, 489(322–472)/400(329–695)mGy·cm, C: 97.5(71.6–149.2)/63.1(49.1–83.7)mGy, 627(496–740)/404(316–515)mGy·cm, D: 67.0(40.3–86.6)/39.7(29.9–89.0)mGy, 392(267–596)/207(166–402)mGy·cm and E: 100.1(66.5–162.6)/62.5(48.0–90.0)mGy, 521(385–619)/315(240–452)mGy·cm. Radiation exposure with powered drill was significantly lower for ilium and sacrum, while procedural duration was not increased for any anatomical location. Local DRLs could be depicted as follows (CTDIvol/DLP): A: 91 mGy/522 mGy·cm, B: 90 mGy/530 mGy·cm, C: 116 mGy/740 mGy·cm, D: 87 mGy/578 mGy·cm and E: 115 mGy/546 mGy·cm. The diagnostic yield was 82.4% for manual and 89.4% for powered drill biopsies. Conclusion Use of powered drill bone biopsy systems for CT-guided percutaneous bone biopsies can significantly reduce the radiation burden compared to manual biopsy for specific anatomical locations such as ilium and sacrum and does not increase radiation dose or procedural duration for any of the investigated locations. Level of Evidence Level 3.


Author(s):  
Anas M Ababneh ◽  
Qutad M Samarah

Abstract It is inevitable that we are exposed to radiation daily from various sources and products that we consume on daily basis. The use of toothpaste for oral hygiene is one of the most common daily practices by humans and yet very little data are available regarding its radiation content. In this work, we investigated the concentrations of gamma emitting radionuclides in toothpaste samples consumed in Jordan. 40K and 226Ra were detected in almost one-third of the samples, whereas 228Ra was detected in nearly half of them. The corresponding activity concentrations in the detected samples were in the ranges of 68.7–154.2, 4.6–14.1 and 1.3–10.0 Bq/kg, respectively. Dose assessment of accidental ingestion of toothpaste for children and adults was made, and its contribution to the annual effective dose was found to be very minimal with maximum doses of ~2.9 and 1.3 μSv for children and adults, respectively.


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