PMID- 34488213
OWN - NLM
STAT- MEDLINE
DCOM- 20220126
LR  - 20220126
IS  - 1361-6498 (Electronic)
IS  - 0952-4746 (Linking)
VI  - 41
IP  - 4
DP  - 2021 Nov 24
TI  - Simplified approach to estimation of organ absorbed doses for patients undergoing 
      abdomen and pelvis CT examination.
LID - 10.1088/1361-6498/ac241d [doi]
AB  - The volumetric computed tomography (CT) dose index (CTDI(vol)) is the measure of 
      output displayed on CT consoles relating to dose within a standard phantom. This 
      gives a false impression of doses levels within the tissues of smaller patients 
      in Southeast Asia. A size-specific dose estimate (SSDE) can be calculated from 
      the CTDI(vol)to provide an assessment of doses at specific positions within a 
      scan using size-specific conversion factors. SSDE is derived using the water 
      equivalent diameter (D(w)) of the patient, but calculation ofD(w)requires 
      sophisticated computer software. This study aimed to evaluate relationships 
      betweenD(W)and effective diameter (D(Eff)), which can be measured more readily, 
      in order to estimate SSDE at various positions within a routine clinical abdomen 
      and pelvis CT examination for Thai patients. An in-house ImageJ algorithm was 
      developed to measureD(w), effective diameter (D(Eff)), and SSDE on CT slices 
      located at the heart, liver, kidneys, colon, and bladder, on 181 CT examinations 
      of abdomen and pelvis. Relationships betweenD(Eff)andD(w)were determined, and 
      values of organ absorbed dose usingD(Eff)were estimated. This approach was 
      validated using a second cohort of 54 patients scanned on a different CT scanner. 
      The results revealed that ratios betweenD(Eff)andD(w)at the heart level were 
      1.11-1.13 and those for the others were about 1.00. Additionally, the 
      SSDE/CTDI(vol)ratio was estimated for each organ in terms of exponential 
      functions using the relationships betweenD(w)andD(Eff)for individual organs. In 
      summary, this study proposed a simple method for estimation of organ absorbed 
      doses for Southeast Asian patients undergoing abdomen and pelvis CT examinations 
      where sophisticated computer software is not available.
CI  - (c) 2021 Society for Radiological Protection. Published on behalf of SRP by IOP 
      Publishing Limited. All rights reserved.
FAU - Sookpeng, S
AU  - Sookpeng S
AUID- ORCID: 0000-0003-1796-3199
AD  - Radiological Technology Department, Faculty of Allied Health Sciences, Naresuan 
      University, Muang, Phitsanulok Province, 65000 Thailand.
FAU - Martin, C J
AU  - Martin CJ
AUID- ORCID: 0000-0002-0784-9002
AD  - Department of Clinical Physics and Bioengineering, University of Glasgow, Glasgow 
      G12 8QQ, United Kingdom.
FAU - Lopez-Gonzalez, M R
AU  - Lopez-Gonzalez MR
AD  - Department of Clinical Physics and Bioengineering, Institute of Neurosciences and 
      Psychology, University of Glasgow, Glasgow, G12 8QQ, United Kingdom.
LA  - eng
PT  - Journal Article
DEP - 20211124
PL  - England
TA  - J Radiol Prot
JT  - Journal of radiological protection : official journal of the Society for 
      Radiological Protection
JID - 8809257
SB  - IM
MH  - *Abdomen
MH  - Humans
MH  - Pelvis/diagnostic imaging
MH  - Phantoms, Imaging
MH  - Radiation Dosage
MH  - *Tomography, X-Ray Computed
OTO - NOTNLM
OT  - CTDIvol
OT  - SSDE
OT  - effective diameter
OT  - water equivalent diameter
EDAT- 2021/09/07 06:00
MHDA- 2022/01/27 06:00
CRDT- 2021/09/06 20:28
PHST- 2021/07/23 00:00 [received]
PHST- 2021/09/06 00:00 [accepted]
PHST- 2021/09/07 06:00 [pubmed]
PHST- 2022/01/27 06:00 [medline]
PHST- 2021/09/06 20:28 [entrez]
AID - 10.1088/1361-6498/ac241d [doi]
PST - epublish
SO  - J Radiol Prot. 2021 Nov 24;41(4). doi: 10.1088/1361-6498/ac241d.