Knowledge of radiation exposure associated with common trauma imaging modalities among orthopaedic surgeons,emergency medicine physicians,and general surgeons in the United States

BACKGROUND:Few contemporary studies have assessed physicians’knowledge of radiation exposure associated with common imaging studies,especially in trauma care.The purpose of this study was to assess the knowledge of physicians involved in caring for trauma patients regarding the effective radiation doses of musculoskeletal(MSK)imaging studies routinely utilized in the trauma setting.METHODS:An electronic survey was distributed to United States orthopaedic surgery,general surgery,and emergency medicine(EM)residency programs.Participants were asked to estimate the radiation dose for common imaging modalities of the pelvis,lumbar spine,and lower extremity,in terms of chest X-ray(CXR)equivalents.Physician estimates were compared to the true effective radiation doses.Additionally,participants were asked to report the frequency of discussing radiation risk with patients.RESULTS:A total of 218 physicians completed the survey;102(46.8%)were EM physicians,88(40.4%)wereorthopaedicsurgeons,and28(12.8%)weregeneralsurgeons.Physicians underestimated the effective radiation doses of nearly all imaging modalities,most notably for pelvic computed tomaography(CT)(median 50 CXR estimation vs.162 CXR actual)and lumbar CT(median 50 CXR estimation vs.638 CXR actual).There was no difference between physician specialties regarding estimation accuracy(P=0.133).Physicians who regularly discussed radiation risks with patients more accurately estimated radiation exposure(P=0.007).CONCLUSION:The knowledge among orthopaedic and general surgeons and EM physicians regarding the radiation exposure associated with common MSK trauma imaging is lacking.Further investigation with larger scale studies is warranted,and additional education in this area may improve care.

Prospective Study of Low-and Standard-dose Chest CT for Pulmonary Nodule Detection:A Comparison of Image Quality,Size Measurements and Radiation Exposure

Objective:To comprehensively and accurately analyze the out-performance of low-dose chest CT(LDCT)vs.standard-dose CT(SDCT).Methods:The image quality,size measurements and radiation exposure for LDCT and SDCT protocols were evaluated.A total of 117 patients with extra-thoracic malignancies were prospectively enrolled for non-enhanced CT scanning using LDCT and SDCT protocols.Three experienced radiologists evaluated subjective image quality independently using a 5-point score system.Nodule detection efficiency was compared between LDCT and SDCT based on nodule characteristics(size and volume).Radiation metrics and organ doses were analyzed using Radimetrics.Results:The images acquired with the LDCT protocol yielded comparable quality to those acquired with the SDCT protocol.The sensitivity of LDCT for the detection of pulmonary nodules(n=650)was lower than that of SDCT(n=660).There was no significant difference in the diameter and volume of pulmonary nodules between LDCT and SDCT(for BMI<22 kg/m^(2),4.37 vs.4.46 mm,and 43.66 vs.46.36 mm^(3);for BMI>22 kg/m^(2),4.3 vs.4.41 mm,and 41.66 vs.44.86 mm^(3))(P>0.05).The individualized volume CT dose index(CTDI_(vol)),the size specific dose estimate and effective dose were significantly reduced in the LDCT group compared with the SDCT group(all P<0.0001).This was especially true for dose-sensitive organs such as the lung(for BMI<22 kg/m^(2),2.62 vs.12.54 mSV,and for BMI>22 kg/m^(2),1.62 vs.9.79 mSV)and the breast(for BMI<22 kg/m^(2),2.52 vs.10.93 mSV,and for BMI>22 kg/m^(2),1.53 vs.9.01 mSV)(P<0.0001).Conclusion:These results suggest that with the increases in image noise,LDCT and SDCT exhibited a comparable image quality and sensitivity.The LDCT protocol for chest scans may reduce radiation exposure by about 80% compared to the SDCT protocol.

Comparison of two reader modes of computer-aided diagnosis in lung nodules on low-dose chest CT scan

Low-dose computerized tomography(LDCT)scanning is of great significance for monitoring and management of pulmonary nodules on chest computerized tomography(CT).Nevertheless,the malignant potential of these nodules is often difficult to detect,especially for some smaller pulmonary nodules on LDCT images.Recent advances using the state-of-art computer-aided detection(CAD)system have attempted to address this problem by identifying small nodules that can be easily missed during clinical practice.CAD is used in two reading modes:Concurrent-reader(CR)mode or second-reader(SR)mode.In this study,we prospectively evaluated the efficiency of a CAD system's SR and CR modes in detecting pulmonary nodules on LDCT.We found that the SR mode improves pulmonary nodule detection regardless of the dose and ex-perience level,especially for interns in the low-dose setting.The CR mode maintains the sensi-tivity of SR mode while significantly decreasing reading times.

Rotational Angiography for 3D Roadmapping of Catheter Interventions in Congenital Heart Disease: Comparison of a Diagnostic and a Low Dose Program

Objectives: To compare the image quality, accuracy and effective dose of the default diagnostic pro-gram with the low dose program. Methods: The diagnostic and low dose programs of three-dimen-sional rotational angiography were compared considering their signal to noise ratio, their carrier to noise ratio and their actual radiation dose in μGy⋅m2/kg. An anthropomorphic phantom underwent both types of scans to evaluate the effective dose. Comparative measurements of vessel diameters were taken in the diagnostic and the low dose program and compared to the angiography as exact basis. The image quality of the scans using the different programs was rated by a specialist physician. Results: The low dose scan does use significantly less radiation and still provides images, which are adequate for 3D navigation of catheter-based interventions. Conclusion: Three-dimensional rotational angiography can be applied with the low dose program and is sufficient for 3D navigation.

An investigation on patient dose in screen-film diagnostic radiology in Lhasa City,Xizang Autonomous Region,China

This study aimed to investigate patient dose in diagnostic screen-film radiographic examinations in the city of Lhasa,China.Seven out of the twenty-six hospitals registered with the Lhasa Health Bureau were included in the investigation.The entrance surface air Kerma(ESAK)of seven conventional screen-film radiology X-ray equipment in these hospitals was measured with a QA dosimeter in September 2012.The X-ray examinations were divided into three categories:PA(posterior-anterior)chest,upper/lower limb,and AP(anterior-posterior)lumbar spine.For each category,ESAKs were calculated and analyzed.The mean ESAK was 0.6 mGy for PA chest,0.3 mGy for upper/lower limb,and 1.8 mGy for AP lumbar spine.In addition,the mean ESAK value recorded for PA chest X-ray examinations exceeded the corresponding value recommended by the International Atomic Energy Agency(0.4 mGy).