The comparison of Size-Specific Dose Estimate (SSDE) in chest CT examination calculated based on volumetric CT Dose Index (CTDIvol) reference phantom and Dose Length Product (DLP)

Abstract We assessed variations in chest CT usage, radiation dose and image quality in COVID-19 pneumonia. Our study included all chest CT exams performed in 533 patients from 6 healthcare sites from Brazil. We recorded patients’ age, gender and body weight and the information number of CT exams per patient, scan parameters and radiation doses (volume CT dose index—CTDIvol and dose length product—DLP). Six radiologists assessed all chest CT exams for the type of pulmonary findings and classified CT appearance of COVID-19 pneumonia as typical, indeterminate, atypical or negative. In addition, each CT was assessed for diagnostic quality (optimal or suboptimal) and presence of artefacts. Artefacts were frequent (367/841), often related to respiratory motion (344/367 chest CT exams with artefacts) and resulted in suboptimal evaluation in mid-to-lower lungs (176/344) or the entire lung (31/344). There were substantial differences in CT usage, patient weight, CTDIvol and DLP across the participating sites.

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Use of Multiphase CT Protocols in 18 Countries: Appropriateness and Radiation Doses

Canadian Association of Radiologists Journal ◽

10.1177/0846537119888390 ◽

2020 ◽

pp. 084653711988839 ◽

Cited By ~ 2

Author(s):

Shivam Rastogi ◽

Ramandeep Singh ◽

Riddhi Borse ◽

Petra Valkovic Zujic ◽

Doris Segota ◽

...

Keyword(s):

Radiation Dose ◽

Chest Ct ◽

Radiation Doses ◽

Energy Agency ◽

Dose Length Product ◽

Ct Dose ◽

Clinical Indications ◽

Ct Dose Index ◽

Multiphase Ct ◽

Routine Chest

Purpose: To assess the frequency, appropriateness, and radiation doses associated with multiphase computed tomography (CT) protocols for routine chest and abdomen–pelvis examinations in 18 countries. Materials and Methods: In collaboration with the International Atomic Energy Agency, multi-institutional data on clinical indications, number of scan phases, scan parameters, and radiation dose descriptors (CT dose–index volume; dose–length product [DLP]) were collected for routine chest (n = 1706 patients) and abdomen–pelvis (n = 426 patients) CT from 18 institutions in Asia, Africa, and Europe. Two radiologists scored the need for each phase based on clinical indications (1 = not indicated, 2 = probably indicated, 3 = indicated). We surveyed 11 institutions for their practice regarding single-phase and multiphase CT examinations. Data were analyzed with the Student t test. Results: Most institutions use multiphase protocols for routine chest (10/18 institutions) and routine abdomen–pelvis (10/11 institutions that supplied data for abdomen–pelvis) CT examinations. Most institutions (10/11) do not modify scan parameters between different scan phases. Respective total DLP for 1-, 2-, and 3-phase routine chest CT was 272, 518, and 820 mGy·cm, respectively. Corresponding values for 1- to 5-phase routine abdomen–pelvis CT were 400, 726, 1218, 1214, and 1458 mGy cm, respectively. For multiphase CT protocols, there were no differences in scan parameters and radiation doses between different phases for either chest or abdomen–pelvis CT ( P = 0.40-0.99). Multiphase CT examinations were unnecessary in 100% of routine chest CT and in 63% of routine abdomen–pelvis CT examinations. Conclusions: Multiphase scan protocols for the routine chest and abdomen–pelvis CT examinations are unnecessary, and their use increases radiation dose.

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CORRIGENDUM TO: TOWARD NATIONAL CT DIAGNOSTIC REFERENCE LEVELS IN THE UNITED ARAB EMIRATES: A MULTICENTER REVIEW OF CT DOSE INDEX AND DOSE LENGTH PRODUCT

Radiation Protection Dosimetry ◽

10.1093/rpd/ncaa155 ◽

2020 ◽

Vol 190 (4) ◽

pp. 473-473

Author(s):

Mohamed M Abuzaid ◽

Wiam Elshami ◽

A El Serafi ◽

T Hussien ◽

J R McConnell ◽

...

Keyword(s):

United Arab Emirates ◽

Diagnostic Reference Levels ◽

Reference Levels ◽

Dose Length Product ◽

Ct Dose ◽

Ct Dose Index ◽

Dose Index

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SU-GG-I-14: A Method to Estimate Cone-Beam CT Dose Index and Cone-Beam Dose Length Product

Medical Physics ◽

10.1118/1.3468047 ◽

2010 ◽

Vol 37 (6Part3) ◽

pp. 3104-3104

Author(s):

S Kim ◽

H Song ◽

E Samei ◽

F Yin ◽

T Yoshizumi

Keyword(s):

Cone Beam Ct ◽

Cone Beam ◽

Dose Length Product ◽

Ct Dose ◽

Ct Dose Index ◽

Beam Dose ◽

Dose Index

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Dose Is Not Always What It Seems: Where Very Misleading Values Can Result From Volume CT Dose Index and Dose Length Product

Journal of the American College of Radiology ◽

10.1016/j.jacr.2013.10.010 ◽

2014 ◽

Vol 11 (3) ◽

pp. 233-237 ◽

Cited By ~ 12

Author(s):

J. Anthony Seibert ◽

John M. Boone ◽

Sandra L. Wootton-Gorges ◽

Ramit Lamba

Keyword(s):

Dose Length Product ◽

Ct Dose ◽

Ct Dose Index ◽

Volume Ct ◽

Dose Index

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Reduced Kilovoltage in Computed Tomography–Guided Intervention in a Community Hospital: Effect on the Radiation Dose

Canadian Association of Radiologists Journal ◽

10.1016/j.carj.2014.04.002 ◽

2014 ◽

Vol 65 (4) ◽

pp. 345-351 ◽

Cited By ~ 6

Author(s):

Saman Rezazadeh ◽

Steven J. Co ◽

Simon Bicknell

Keyword(s):

Low Dose ◽

Effective Diameter ◽

Tube Voltage ◽

Dose Length Product ◽

Ct Guided ◽

Ct Dose ◽

Patient Size ◽

Ct Dose Index ◽

Volume Ct ◽

Dose Index

Purpose The purpose of this study was to determine whether low-kilovoltage (80 or 100 kV) computed tomography (CT)-guided interventions performed in a community-based hospital are feasible and to compare radiation exposure incurred with conventional 120 kV potential. Materials and Methods Effective doses (ED) received by patients who underwent CT-guided intervention were analysed before and after a low-dose kilovoltage protocol was instituted in our department. We performed CT-guided procedures of 93 consecutive patients by using conventional 120-kV tube voltage (50 patients) and a low voltage of 80 or 100 kV for the remainder of this cohort. Automatic tube current modulation was enabled to obtain the best image quality. Procedure details were prospectively recorded and included examination site and type, slice width, tube voltage and current, dose length product, volume CT dose index, and size-specific dose estimate. Dose length product was converted to ED to account for radiosensitivity of specific organs. Statistical comparisons with test differences in the ED, volume CT dose index, size-specific dose estimate, and effective diameter (patient size) were made by using the Student t test. Results All but 6 of the procedures performed at 80 kV were successful, for a success rate of 86%. At lower voltages, the ED was significantly ( P < .01) reduced, on average, by 57%, 73%, and 65% for the pelvic, chest, and abdomen procedures, respectively. Conclusion A low-dose radiation technique by using 80 or 100 kV results in a high technical success rate for pelvic, chest, and abdomen CT-guided interventional procedures, although dramatically decreasing radiation exposure. There was no significant difference in effective diameter (patient size) between the conventional and the low-dose groups, which would suggest that dose reduction was indeed a result of kVp change and not patient size.

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The comparison of size-specific dose estimate in CT examination based on head and body PMMA phantom

Journal of Physics and Its Applications ◽

10.14710/jpa.v1i1.3905 ◽

2018 ◽

Vol 1 (1) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Mohd Hanafi Ali ◽

Choirul Anam ◽

Freddy Haryanto ◽

Geoff Dougherty

Keyword(s):

Equivalent Diameter ◽

Correction Factors ◽

K Value ◽

Dose Estimate ◽

Light Speed ◽

Ct Examination ◽

Ct Dose ◽

Patient Size ◽

Ct Dose Index ◽

The Impact

Nowadays, a dose estimate for individual patients undergoing CT examination is carried out using the metric of size-specific dose estimate (SSDE), which is calculated by multiplying a volume CT dose index (CTDIvol) and a correction factor that is a function of patient size. Two CTDIvol values are based on head and body PMMA phantoms. There are also two values of correction factors (k), both for head and body PMMA phantoms. The purpose of this study was to compare the SSDE values calculated using head and body PMMA phantoms with their corresponding correction factors (k). The CTDIvol values were derived from the ImPACT 1.04 software for 12 CT scanners: Sensation 4, Sensation 16, Sensation 64, Light Speed, Light Speed 16, Light Speed VCT, Secura, Brilliance 16, Brilliance 64, Asteion Dual, Aquilion 4, and Aquilion 16. The size of the patients who underwent CT examination was characterized by a water-equivalent diameter (Dw) from 10 cm to 45 cm. The results indicated that the differences in SSDE values based on head and body CTDIvol were within 20%. Thus, the SSDE value can be calculated using the head or body CTDIvol bases with corresponding k value.

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VOLUME CT DOSE INDEX AND DOSE-LENGTH PRODUCT VALUES ACCORDING TO FACILITY SIZE IN JAPAN

Radiation Protection Dosimetry ◽

10.1093/rpd/ncz284 ◽

2020 ◽

Vol 188 (2) ◽

pp. 261-269

Author(s):

Yuta Matsunaga ◽

Yuya Kondo ◽

Kenichi Kobayashi ◽

Masanao Kobayashi ◽

Kazuyuki Minami ◽

...

Keyword(s):

Computed Tomography ◽

Contrast Agent ◽

Ct Scanner ◽

Dose Length Product ◽

Ct Dose ◽

Volume Computed Tomography ◽

Ct Dose Index ◽

Computed Tomography Dose Index ◽

Facility Size ◽

Dose Index

Abstract The aim of this study was to investigate differences in volume computed tomography dose index (CTDIvol) and dose-length product (DLP) values according to facility size in Japan. A questionnaire survey was sent to 3000 facilities throughout Japan. Data from each facility were collected including bed number, computed tomography (CT) scan parameters employed and the CTDIvol and/or DLP values displayed on the CT scanner during each examination. The CTDIvol and DLP for 11 adult and 6 paediatric CT examinations were surveyed. Comparison of CTDIvol and DLP values of each examination according to facility size revealed key differences in CT dose between small and large facilities. This study highlights the importance of lowering the dose of coronary artery examination with contrast agent in smaller facilities and of lowering the dose of adult and paediatric head CT without contrast agent in larger facilities. The results of this study are valid in Japan.

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Volume CT Dose Index and Dose-Length Product Displayed during CT: What Good Are They?

Radiology ◽

10.1148/radiol.10100297 ◽

2011 ◽

Vol 258 (1) ◽

pp. 236-242 ◽

Cited By ~ 112

Author(s):

Walter Huda ◽

Fred A. Mettler

Keyword(s):

Dose Length Product ◽

Ct Dose ◽

Ct Dose Index ◽

Volume Ct ◽

Dose Index

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