scholarly journals CT of the medial clavicular epiphysis for forensic age estimation: hands up?

2021 ◽  
Author(s):  
Magdalini Tozakidou ◽  
Rieke L. Meister ◽  
Lennart Well ◽  
Kay U. Petersen ◽  
Sebastian Schindera ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Effective Dose ◽  
Age Estimation ◽  
Image Noise ◽  
Ct Scans ◽  
Forensic Age Estimation ◽  
Quantitative Image ◽  
The Impact ◽  
Medial Clavicular Epiphysis ◽  
Scan Length

Abstract Purpose The aim of this study was to assess the impact of arm position in computed tomography (CT) of the clavicle performed for forensic age estimation on clavicular position, image noise, and radiation dose. Methods and materials Forty-seven CT scans of the medial clavicular epiphysis performed for forensic age estimation were conducted with either hands and arms held upwards (CTHU, 28 persons) or positioned at the body (CTHD, 19 persons). Presets were identical for both positions (70 mAs/140 kVp; Brilliance iCT, Philips). Each CT scan was reconstructed with an iterative algorithm (i-Dose 4) and evaluated at the middle of the sternoclavicular joint. Clavicular angle was measured on a.p. topograms in relation to a horizontal line. Quantitative image noise was measured in air at the level of medial clavicular epiphysis. Effective dose and scan length were recorded. Results Hands-up position compared with hands-down position resulted in a lower lateral body diameter (CTHU 41.1 ± 3.6 cm vs. CTHD 44.6 ± 3.1 cm; P = 0.03), a reduced quantitative image noise (CTHU: 39.5 ± 9.2; CTHD: 46.2 ± 8.3; P = 0.02), and lower CTDIvol (5.1 ± 1.4 mGy vs. 6.7 ± 1.8 mGy; P = 0.001). Scan length was longer in patients examined with hands up (HU: 8.5 ± 3.4 cm; HD: 6.2 ± 2.1 cm; P = 0.006). Mean effective dose for CTHU was 0.79 ± 0.32 mSv compared with 0.95 ± 0.38 mSv in CTHD (P = 0.12). Clavicular angle was 17° ± 6° in patients with hands down and 32° ± 7° in patients with hands up (P < 0.001). Conclusion By elevated arm positioning, the image quality of clavicular CT scans can be improved while maintaining radiation dose compared with hands down. Clavicular position differs according to the hand position. Thus, positioning patients with elevated hands is advisable for forensic clavicular CT examinations, but multiplanar CT reconstructions should be adjusted to clavicular position and scan length should be reduced to a minimum.

scholarly journals Reducing Radiation Dose in Emergency CT Scans While Maintaining Equal Image Quality: Just a Promise or Reality for Severely Injured Patients?

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Ulrich Grupp ◽  
Max-Ludwig Schäfer ◽  
Henning Meyer ◽  
Alexander Lembcke ◽  
Alexander Pöllinger ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Effective Dose ◽  
Dose Reduction ◽  
Iterative Reconstruction ◽  
Study Groups ◽  
Image Noise ◽  
Effective Radiation Dose ◽  
Total Body ◽  
Effective Radiation ◽  
The Impact

Objective. This study aims to assess the impact of adaptive statistical iterative reconstruction (ASIR) on CT imaging quality, diagnostic interpretability, and radiation dose reduction for a proven CT acquisition protocol for total body trauma.Methods. 18 patients with multiple trauma (ISS≥16) were examined either with a routine protocol (n=6), 30% (n=6), or 40% (n=6) of iterative reconstruction (IR) modification in the raw data domain of the routine protocol (140 kV, collimation: 40, noise index: 15). Study groups were matched by scan range and maximal abdominal diameter. Image noise was quantitatively measured. Image contrast, image noise, and overall interpretability were evaluated by two experienced and blinded readers. The amount of radiation dose reductions was evaluated.Results. No statistically significant differences between routine and IR protocols regarding image noise, contrast, and interpretability were present. Mean effective dose for the routine protocol was25.3±2.9 mSv,19.7±5.8 mSv for the IR 30, and17.5±4.2 mSv for the IR 40 protocol, that is, 22.1% effective dose reduction for IR 30 (P=0.093) and 30.8% effective dose reduction for IR 40 (P=0.0203).Conclusions. IR does not reduce study interpretability in total body trauma protocols while providing a significant reduction in effective radiation dose.

Radiation exposure during the treatment of spinal deformities

2021 ◽  
pp. 1-7
Author(s):  
Jwalant S. Mehta ◽  
Kirsten Hodgson ◽  
Lu Yiping ◽  
James Swee Beng Kho ◽  
Ravindra Thimmaiah ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Ionizing Radiation ◽  
Effective Dose ◽  
Spinal Deformity ◽  
Background Radiation ◽  
Ct Scans ◽  
Intraoperative Fluoroscopy ◽  
The Difference ◽  
Risk Of Cancer ◽  
Surgical Group

Aims To benchmark the radiation dose to patients during the course of treatment for a spinal deformity. Methods Our radiation dose database identified 25,745 exposures of 6,017 children (under 18 years of age) and adults treated for a spinal deformity between 1 January 2008 and 31 December 2016. Patients were divided into surgical (974 patients) and non-surgical (5,043 patients) cohorts. We documented the number and doses of ionizing radiation imaging events (radiographs, CT scans, or intraoperative fluoroscopy) for each patient. All the doses for plain radiographs, CT scans, and intraoperative fluoroscopy were combined into a single effective dose by a medical physicist (milliSivert (mSv)). Results There were more ionizing radiation-based imaging events and higher radiation dose exposures in the surgical group than in the non-surgical group (p < 0.001). The difference in effective dose for children between the surgical and non-surgical groups was statistically significant, the surgical group being significantly higher (p < 0.001). This led to a higher estimated risk of cancer induction for the surgical group (1:222 surgical vs 1:1,418 non-surgical). However, the dose difference for adults was not statistically different between the surgical and non-surgical groups. In all cases the effective dose received by all cohorts was significantly higher than that from exposure to natural background radiation. Conclusion The treatment of spinal deformity is radiation-heavy. The dose exposure is several times higher when surgical treatment is undertaken. Clinicians should be aware of this and review their practices in order to reduce the radiation dose where possible.

Optimization of computed tomography urography protocol, 1997 to 2008: Effects on radiation dose

2009 ◽  
Vol 50 (4) ◽  
pp. 446-454 ◽  
Author(s):  
P. Dahlman ◽  
L. Jangland ◽  
M. Segelsjö ◽  
A. Magnusson
Keyword(s):  
Computed Tomography ◽  
Radiation Dose ◽  
Effective Dose ◽  
Excretory Urography ◽  
Ct Urography ◽  
Tube Current Modulation ◽  
Current Modulation ◽  
Tube Current ◽  
The Mean ◽  
The Impact

Background: Since computed tomography (CT) urography began to replace excretory urography as the primary imaging technique in uroradiology, the collective radiation dose to the patients has increased. Purpose: To examine the changes in the CT urography protocol for investigating suspected urinary tract malignancy between the years 1997 and 2008, and how these changes have influenced the mean effective dose. Material and Methods: The study was based on 102 patients (mean age 66.1±14.8 years, range 31–89 years; 30 female, 72 male) divided into five groups (groups A–E) corresponding to the time points at which changes were made to the CT urography protocol. The mean effective doses were estimated using the ImPACT CT Patient Dosimetry Calculator. Results: The number of scan phases at CT urography was reduced from four to three in 1999, resulting in a reduction of the mean effective dose from 29.9/22.5 (female [F]/male [M]) mSv (group A) to 26.1/18.9 (F/M) mSv (group B). In 2001, mAs settings were adapted to patient size, and the mean effective dose was reduced to 16.8/12.0 (F/M) mSv (group C). In 2005, scans were performed with a multidetector-row CT equipped with automatic tube current modulation in the x- and y-axis (CARE Dose). The effective mAs was also lowered in the unenhanced and excretory phase, yet the mean effective dose increased to 18.2/13.1 (F/M) mSv (group D), since the effective mAs had to be increased in the corticomedullary phase to maintain image quality. In 2008, as tube current modulation in the x-, y-, and z-axis was introduced (CARE Dose4D), the mean effective dose was reduced to 11.7/8.8 (F/M) mSv (group E). Conclusion: This study shows that the individual mean effective dose to patients undergoing CT urography has decreased by 60%, from 29.9/22.5 (F/M) mSv in 1997 to 11.7/8.8 (F/M) mSv in 2008.

Forensic age estimation by the Schmeling method: computed tomography analysis of the medial clavicular epiphysis

2014 ◽  
Vol 129 (1) ◽  
pp. 203-210 ◽  
Author(s):  
Oguzhan Ekizoglu ◽  
Elif Hocaoglu ◽  
Ercan Inci ◽  
Ibrahim Sayin ◽  
Dilek Solmaz ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Age Estimation ◽  
Forensic Age Estimation ◽  
Tomography Analysis ◽  
Schmeling Method ◽  
Medial Clavicular Epiphysis

Quantifying decreased radiation exposure from modern CT scan surveillance programs of germ cell tumors.

2016 ◽  
Vol 34 (2_suppl) ◽  
pp. 478-478
Author(s):  
Stephanie Anne Holler Howard ◽  
Michael Rosenthal ◽  
Lei Qin ◽  
Brandon David Bernard ◽  
Clair Beard ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Radiation Exposure ◽  
Transport Model ◽  
Biological Effects ◽  
Absolute Risk ◽  
Clinical Stage ◽  
Germ Cell Tumors ◽  
Ct Scans ◽  
Rank Test ◽  
The Impact

478 Background: Active surveillance (AS) is increasingly used to manage clinical stage I testicular cancer (CS1TC,) but has the risk of radiation exposure from CT scans. Modern CT scanners with iterative reconstruction techniques (IRT) produce equivalent image quality with less radiation dose compared with traditional filtered back projection (FBP). Data examining timing of CS1TC relapses on AS have suggested it is safe to decrease CT scanning of abdomen and pelvis from the NCCN 2009 guideline of approximately 16 scans over 5 years to 7 scans. We examine the impact of the CT upgrade and decreased scans on radiation dose and associated risks. Methods: This IRB-approved study enrolled 24 CS1TC patients who had CT scans on the same Toshiba Aquilion 64 CT before and after IRT software installation. Dose-length product and CT dose index volume were recorded. A medical physicist calculated effective doses. Radiation doses were compared using the Wilcoxon signed rank test. Median effective dose per scan was multiplied by scan number based on 16 and 7 scan 5 year AS protocols to calculate an estimated cumulative dose (ECD). Lifetime attributable risk (LAR) of dying of a radiation-associated solid tumor was estimated for a single exposure at age 35 using the excess absolute risk transport model from the Biological Effects of Ionizing Radiation VII analysis of long-term atomic bomb survivors. Results: Median pre and post upgrade doses were 12.5 mSv and 7.7 mSv respectively (p < 0.0001). A linear regression model with a constrained zero intercept fit to the data found that IRT dose was best estimated as 61% of FBP dose (95% CI 0.56 – 0.66). Table 1 lists ECD and LAR data for both AS regimens pre and post upgrade. Conclusions: IRT, as part of an integrated approach to optimize patient outcome, should reduce CT-related risks by about 39%. This reduction, combined with the scan reduction of newer AS regimens, further significantly lowers the already small potential mortality of imaging associated cancers. [Table: see text]

Effect of Thermal Insulation on Image Quality and Radiation Dose in Polytrauma Computed Tomography

2020 ◽  
Vol 71 (2) ◽  
pp. 238-243
Author(s):  
Paweł Podsiadło ◽  
Robert Chrzan ◽  
Grzegorz Liszka ◽  
Tomasz Sanak ◽  
Sylweriusz Kosiński ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Image Quality ◽  
Radiation Dose ◽  
Thermal Insulation ◽  
Noise Intensity ◽  
Independent Risk Factor ◽  
Ct Scans ◽  
Self Heating ◽  
The Impact ◽  
Image Homogeneity

Purpose: Unintentional drop in body temperature in trauma victims is an independent risk factor for mortality. We aimed to assess the impact of thermal insulation on image quality and radiation dose in polytrauma computed tomography (CT). Methods: Thirteen different insulating covers were used to wrap CT phantoms. Images were assessed subjectively at a radiological workstation and analyzed digitally with dedicated software evaluating the noise intensity, spatial resolution, and image homogeneity. The radiation dose was measured using a dosimeter. Results: Most materials did not cause significant artifacts apart from 2 heating pads. Although the radiation dose was increased by the majority of insulating covers (up to 64.66%), certain covers decreased the absorbed radiation (up to −7.35%). Conclusions: The majority of insulating systems do not cause artifacts in CT scans. When using covers with self-heating warmers, removing the heating pad is suggested due to the risk of considerable artifacts appearing. Certain insulating covers may increase or decrease the radiation dose.

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