Entrance surface air kerma in X-ray systems for paediatric interventional cardiology: a national survey

2015 ◽  
Vol 165 (1-4) ◽  
pp. 107-110 ◽  
Author(s):  
C. Ubeda ◽  
E. Vano ◽  
P. Miranda ◽  
E. Valenzuela ◽  
F. Vergara ◽  
...  
Keyword(s):  
National Survey ◽  
Interventional Cardiology ◽  
X Ray ◽  
Air Kerma ◽  
Entrance Surface Air Kerma

scholarly journals An Approach for Online Determining the Entrance Surface Air Kerma (ESAK) in Digital Radiology

2021 ◽  
Author(s):  
Ibrahim Idris Suliman
Keyword(s):  
Interventional Radiology ◽  
Digital Imaging ◽  
Digital Information ◽  
Patient Exposure ◽  
Digital Radiology ◽  
X Ray ◽  
Air Kerma ◽  
Dicom Header ◽  
Area Product ◽  
Entrance Surface Air Kerma

Abstract An online method is proposed to determine the entrance surface air kerma (ESAK) in digital radiology from console-displayed kerma area product (PKA) data. ESAK values were calculated from X-ray tube outputs and patient exposure factors across five X-ray examinations. The corresponding PKAvalues were taken from the Digital Imaging and Communications in Medicine (DICOM) header. Using linear regression between ESAK and values, the slope and intercept coefficients for each type of X-ray equipment and procedure were determined. The coefficient to determine ESAK from ranged from 59% for a posteroanterior chest to 88% for anteroposterior lumbar spine view X-ray procedures. The results demonstrated the possibility of online estimates of ESAK from a console that displayed using readily available digital information in radiology. The results may have important implications in interventional radiology, where ESAK values are crucial for preventing skin injuries due to prolonged fluoroscopy times.

scholarly journals Dosimetric evaluation of X-ray examinations of paranasal sinuses in pediatric patients

2016 ◽  
Vol 49 (2) ◽  
pp. 79-85 ◽  
Author(s):  
Beatriz de Lucena Villa-Chan Cantalupo ◽  
Aline Carvalho da Silva Xavier ◽  
Clemanzy Mariano Leandro da Silva ◽  
Marcos Ely Almeida Andrade ◽  
Vinícius Saito Monteiro de Barros ◽  
...  
Keyword(s):  
Paranasal Sinuses ◽  
Pediatric Patients ◽  
Radiological Examination ◽  
Patient Exposure ◽  
X Ray ◽  
Thermoluminescent Dosimeters ◽  
Air Kerma ◽  
Radiosensitive Organs ◽  
The City ◽  
Entrance Surface Air Kerma

Abstract Objective: To estimate the entrance surface air kerma (Ka,e) and air kerma in the region of radiosensitive organs in radiographs of pediatric paranasal sinuses. Materials and Methods: Patient data and irradiation parameters were collected in examinations of the paranasal sinuses in children from 0 to 15 years of age at two children's hospitals in the city of Recife, PE, Brazil. We estimated the Ka,e using the X-ray tube outputs and selected parameters. To estimate the air kerma values in the regions of the eyes and thyroid, we used thermoluminescent dosimeters. Results: The Ka,e values ranged from 0.065 to 1.446 mGy in cavum radiographs, from 0.104 to 7.298 mGy in Caldwell views, and from 0.113 to 7.824 mGy in Waters views. Air kerma values in the region of the eyes ranged from 0.001 to 0.968 mGy in cavum radiographs and from 0.011 to 0.422 mGy in Caldwell and Waters views . In the thyroid region, air kerma values ranged from 0.005 to 0.932 mGy in cavum radiographs and from 0.002 to 0.972 mGy in Caldwell and Waters views. Conclusion: The radiation levels used at the institutions under study were higher than those recommended in international protocols. We recommend that interventions be initiated in order to reduce patient exposure to radiation and therefore the risks associated with radiological examination of the paranasal sinuses.

scholarly journals Comparison of entrance surface air kerma measurement with MTS-N (LiF: Mg, Ti) chips with a kilovoltage X-ray source

2021 ◽  
Vol 22 (1) ◽  
pp. 20-34
Author(s):  
Akintayo Daniel Omojola ◽  
Samuel Olaolu Adeneye ◽  
Michael Onoriode Akpochafor ◽  
Isiaka Olusola Akala ◽  
Azuka Anthonio Agboje
Keyword(s):  
Ionization Chamber ◽  
Radiation Detectors ◽  
Field Size ◽  
Peak Voltage ◽  
X Ray ◽  
Air Kerma ◽  
Image Distance ◽  
The Mean ◽  
Dose Accuracy ◽  
Entrance Surface Air Kerma

Objective: Radiation detectors are key components that ensure the accuracy and performances of dosimetry equipment. The study is aimed to compare the mean entrance surface air kerma (ESAK) between a DCT-10mm ionization chamber (IC) and MTS-N (LiF: Mg, Ti) chips when both detectors are exposed to ≤ 5mGy with a 10 by 10 field size, with an X-ray source and to determine the accuracy of the Thermoluminescent (TL) chips. Also, the dose will be compared to similar studies. Materials and Methods: A functional, Digital Radiography (DR) X-ray System was used. A DCT-10mm ionization chamber (IC) and an XR Multidetector was positioned at a Source to Image Distance (SID) of 100cm on polystyrene, about 20cm thick. An X-ray spectrum generated at a Practical Peak Voltage (PPV) of 60-107kV with Half Value Layer (HVL) of 2.4-4.3mmAl and filtration > 3mmAl was used. The same setup was used for the MTS-N chips. Results: The mean doses for 1-5 mGy with the MTS-N chips were 1.07±0.07, 1.60±0.13, 2.23±0.11, 2.58±0.07 and 3.45±0.10 mGy respectively, with accuracies of 7, 20, 26, 36 and 31%. Dose accuracy at 1and 2mGy was within 25% respectively. Dose accuracies at 3, 4 and 5mGy was within >25%. The correction factor for 1-5mGy was 0.94, 1.25, 1.35, 1.55 and 1.45 respectively. Conclusion: Validation of the MTS-N chips with the reference ionization chamber to this study was within 36%. The Radiation and Nuclear Safety Authority (STUK) recommends that ESAK be within 25% for entrance surface dose. ESAK accuracy mostly increased with dose as observed in this study.

ESTIMATION OF ENTRANCE SURFACE AIR KERMA IN DIGITAL RADIOGRAPHIC EXAMINATIONS

2021 ◽  
Vol 193 (1) ◽  
pp. 16-23
Author(s):  
Chanchal Kaushik ◽  
Inderjeet Singh Sandhu ◽  
A K Srivastava ◽  
Mansi Chitkara
Keyword(s):  
Cervical Spine ◽  
Lumbar Spine ◽  
Dose Assessment ◽  
Dose Calculations ◽  
Energy Agency ◽  
X Ray ◽  
Air Kerma ◽  
Tube Output ◽  
Effective Doses ◽  
Entrance Surface Air Kerma

Abstract Purpose: Contribution of radiation doses from medical X-ray examination to collective dose is significant. Unusually, high doses may increase the risk of stochastic effects of radiations. Therefore, radiation dose assessment was performed in 241 digital X-ray examinations in the study and was compared with published dose reference levels (DRLs). Methods: Entrance surface air kerma (ESAK) was calculated in chest PA, cervical AP/Lat, abdomen AP, lumbar AP/Lat and pelvis AP digital radiographic examinations (119 male and 122 female) following the International Atomic Energy Agency recommended protocol. Initially, 270 digital examinations were selected, reject analysis was performed and final 241 examinations were enrolled in the study for dose calculations. The exposure parameters and X-ray tube output were used for dose calculations. Effective doses were estimated with the help of conversion coefficients from ICRP 103. Results: Median ESAK (mGy) and associated effective doses obtained were cervical spine AP (1.30 mGy, 0.045 mSv), cervical spine Lat (0.25 mGy, 0.005 mSv), chest PA (0.11 mGy, 0.014 mSv), abdomen AP (0.90 mGy, 0.118 mSv), lumbar spine AP (1.52 mGy, 0.177 mSv), lumbar spine Lat (7.76 mGy, 0.209 mSv) and pelvis AP (0.82 mGy, 0.081 mSv). Results were compared with the studies of UK, Oman, India and Canada. Conclusion: The calculated ESAK and effective dose values were less than or close to previously published literature except for cervical spine AP and lumbar spine Lat. The results reinforce the need for radiation protection optimization, improving examination techniques and appropriate use of automatic exposure control in digital radiography. ESAK values reported in this study could further contribute to establishing local DRLs, regional DRLs and national DRLs.

scholarly journals A Study of Entrance Surface Air Kerma for Patients Undergoing Chest and Abdomen from Digital Radiography at Chulabhorn Hospital

2019 ◽  
Vol 37 (1) ◽  
pp. 51
Author(s):  
Atchara Promduang ◽  
Napapong Pongnapang ◽  
Napat Ritlumlert ◽  
Sutthirak Tangruangkiat ◽  
Monchai Phonlakrai
Keyword(s):  
Digital Radiography ◽  
Computed Radiography ◽  
Energy Agency ◽  
X Ray ◽  
Code Of Practice ◽  
Air Kerma ◽  
Technical Report Series ◽  
Male Patients ◽  
The Mean ◽  
Entrance Surface Air Kerma

Objective: The main purpose of this study was to investigate the typical dose for standard-sized patients in chest (posteroanterior; PA) and abdomen (anteroposterior; AP) digital radiography.Material and Methods: The air kerma was measured by the ionization chamber (Radical Corporation, model 10X6-6) in X-ray equipment manufactured by General Electric Healthcare Definium 8000 System for different kilovoltage peak (kVp) settings in each X-ray examination. The entrance surface air kerma (ESAK) was determined in 422 mediumsized patients in different projections: chest (PA) and abdomen (AP), according to the recommended protocol of the International Atomic Energy Agency Technical Report Series Number 457 (Technical Reports Series No. 457 “Dosimetry in Diagnostic Radiology: An International Code of Practice).Results: The mean entrance surface air kerma values for chest (PA) radiography in female and male patients were 0.08 milligray (mGy) and 0.09 mGy, respectively and for abdomen (AP) radiography for both genders were 0.98 mGy and 1.06 mGy, respectively.Conclusion: The mean entrance surface air kerma values of this study were less than the diagnostic reference levels from the IAEA 1996, Korea 2007, United Kingdom 2010 and Japan 2015, in all projections. Patient doses (ESAK) in chest (PA) and abdomen (AP) digital radiography at Chulabhorn Hospital were less than the other guidelines, because of the use of a high kVp technique for the chest and the automatic exposure control for the abdomen. Furthermore, Thai people are smaller than Westerners. We studied in digital radiography only that literally provides lowest radiation dose compares with screen film and computed radiography.

PROPOSED NATIONAL DIAGNOSTIC REFERENCE LEVELS FOR STANDARD RADIOGRAPHIC X-RAY PROCEDURES IN SUDAN

2020 ◽  
Vol 190 (4) ◽  
pp. 419-426
Author(s):  
Nada A Ahmed ◽  
E H Basheir ◽  
A B Farah ◽  
T S Mohammedzein ◽  
I I Suliman
Keyword(s):  
Lumbar Spine ◽  
Dose Optimization ◽  
Radiation Doses ◽  
Diagnostic Reference Levels ◽  
Reference Levels ◽  
X Ray ◽  
Air Kerma ◽  
Tube Output ◽  
The Mean ◽  
Entrance Surface Air Kerma

Abstract This study aimed to calculate patient radiation doses for adults during the seven most commonly performed conventional X-ray procedures, and to propose national diagnostic reference levels (DRLs). A representative sample of patients from 29 hospitals was included. The entrance surface air kerma (ESAK) was calculated by measuring X-ray tube output and the corresponding technical and exposure factors for each patient. Third-quartile values of the mean ESAK distributions were proposed as DRL values. The DRLs in mGy were as follows: 0.6 for chest postero–anterior (PA), 3.5 for skull AP, 1.7 for skull lateral (LAT), 2.7 for abdominal, 2.6 for pelvic AP, 3.7 for lumbar spine AP and 8 for lumbar spine LAT. Compared with literature, the maximum percentages increase were in chest PA (329%) and skull AP (187%). Since the suggested DRL for chest PA was higher than literature values, dose optimization and a review of its value is recommended.

Dosimetry and optimization in digital radiography based on the contrast-detail resolution

2018 ◽  
Vol 6 (3) ◽  
Author(s):  
Wilson Otto Gomes Batista ◽  
Alexandre Gomes De Carvalho
Keyword(s):  
Image Quality ◽  
Inverse Image ◽  
Point Of View ◽  
Complete Analysis ◽  
Portable Devices ◽  
Evaluation Tool ◽  
Air Kerma ◽  
Direct Radiography ◽  
Definition Of ◽  
Entrance Surface Air Kerma

Contrast-detail (C-D) curves are useful in evaluating the radiographic image quality in a global way. The objective of the present study was to obtain the C-D curves and the inverse image quality figure. Both of these parameters were used as an evaluation tool for abdominal and chest imaging protocols. The C-D curves were obtained with the phantom CDRAD 2.0 in computerized radiography and the direct radiography systems (including portable devices). The protocols were 90 and 102 kV in the range of 2 to 20 mAs for the chest and 80 kV in the range of 10 to 80 mAs for the abdomen. The incident air kerma values were evaluated with a solid state sensor. The analysis of these C-D curves help to identify which technique would allow a lower value of the entrance surface air kerma, Ke, while maintaining the image quality from the point of view of C-D detectability. The results showed that the inverse image quality figure, IQFinv, varied little throughout the range of mAs, while the value of Ke varied linearly directly with the mAs values. Also, the complete analysis of the curves indicated that there was an increase in the definition of the details with increasing mAs. It can be concluded that, in the transition phase for the use of the new receptors, it is necessary to evaluate and adjust the practised protocols to ensure, at a minimum, the same levels of the image quality, taking into account the aspects of the radiation protection of the patient.

Impact on dose and image quality of a software-based scatter correction in mammography

2017 ◽  
Vol 59 (6) ◽  
pp. 649-656 ◽  
Author(s):  
Teresa Monserrat ◽  
Elena Prieto ◽  
Benigno Barbés ◽  
Luis Pina ◽  
Arlette Elizalde ◽  
...  
Keyword(s):  
Image Quality ◽  
Scatter Correction ◽  
Inverse Image ◽  
Clinical Image ◽  
Air Kerma ◽  
Average Glandular Dose ◽  
Standard Mode ◽  
Entrance Surface Air Kerma ◽  
Clinical Cases

Background In 2014, Siemens developed a new software-based scatter correction (Progressive Reconstruction Intelligently Minimizing Exposure [PRIME]), enabling grid-less digital mammography. Purpose To compare doses and image quality between PRIME (grid-less) and standard (with anti-scatter grid) modes. Material and Methods Contrast-to-noise ratio (CNR) was measured for various polymethylmethacrylate (PMMA) thicknesses and dose values provided by the mammograph were recorded. CDMAM phantom images were acquired for various PMMA thicknesses and inverse Image Quality Figure (IQFinv) was calculated. Values of incident entrance surface air kerma (ESAK) and average glandular dose (AGD) were obtained from the DICOM header for a total of 1088 pairs of clinical cases. Two experienced radiologists compared subjectively the image quality of a total of 149 pairs of clinical cases. Results CNR values were higher and doses were lower in PRIME mode for all thicknesses. IQFinv values in PRIME mode were lower for all thicknesses except for 40 mm of PMMA equivalent, in which IQFinv was slightly greater in PRIME mode. A mean reduction of 10% in ESAK and 12% in AGD in PRIME mode with respect to standard mode was obtained. The clinical image quality in PRIME and standard acquisitions resulted to be similar in most of the cases (84% for the first radiologist and 67% for the second one). Conclusion The use of PRIME software reduces, in average, the dose of radiation to the breast without affecting image quality. This reduction is greater for thinner and denser breasts.

Sign in / Sign up

Export Citation Format

Share Document