PMID- 37132289
OWN - NLM
STAT- MEDLINE
DCOM- 20230608
LR  - 20230608
IS  - 1526-9914 (Electronic)
IS  - 1526-9914 (Linking)
VI  - 24
IP  - 6
DP  - 2023 Jun
TI  - Estimating size specific dose estimate from computed tomography radiograph 
      localizer with radiation risk assessment.
PG  - e13989
LID - 10.1002/acm2.13989 [doi]
LID - e13989
AB  - BACKGROUND: Quantifying radiation burden is necessary for optimizing imaging 
      protocols. The normalized dose coefficient (NDC) is determined from the 
      water-equivalent diameter (WED) and is used to scale the CTDIvol based on body 
      habitus to determine the size specific dose estimate (SSDE). In this study we 
      determine the SSDE prior to the CT scan and how sensitive the SSDE from WED is to 
      the lifetime attributable risk (LAR) from BEIR VII. METHOD: For calibration, 
      phantom images are used to relate the mean pixel values along a profile ( PPV  ) 
      of the CT localizer to the water-equivalent area (A(W) ) of the CT axial scan at 
      the same z-location. Images of the CTDIvol phantoms (32 cm, 16 cm, and  approximately 1 cm) and 
      ACR phantom (Gammex 464) were acquired on four scanners. The relationship between 
      the A(W) and PPV  was used to calculate the WED from the CT localizer for patient 
      scans. A total of 790 CT examinations of the chest and abdominopelvic regions 
      were used in this study. The effective diameter (ED) was calculated from the CT 
      localizer. The LAR was calculated based on the patient chest and abdomen using 
      the National Cancer Institute Dosimetry System for Computed Tomography (NCICT). 
      The radiation sensitivity index (RSI) and risk differentiability index (RDI) were 
      calculated for SSDE and CTDIvol. RESULTS: The WED from CT localizers and CT 
      axials scans show good correlation (R(2)  = 0.96) with the maximum percentage 
      difference being 13.45%. The NDC from WED correlates poorly with LAR for lungs 
      (R(2)  = 0.18) and stomach (R(2)  = 0.19), however that is the best correlation. 
      CONCLUSION: The SSDE can be determined within 20% as recommended by the report of 
      AAPM TG 220. The CTDIvol and SSDE are not good surrogates for radiation risk, 
      however the sensitivity for SSDE improves when using WED instead of ED.
CI  - (c) 2023 The Authors. Journal of Applied Clinical Medical Physics published by 
      Wiley Periodicals, LLC on behalf of The American Association of Physicists in 
      Medicine.
FAU - Burton, Christiane Sarah
AU  - Burton CS
AD  - Department of Diagnostic Imaging, St Jude Children's Research Hospital, Memphis, 
      Tennessee, USA.
FAU - Al-Ward, Shahad
AU  - Al-Ward S
AD  - Department of Radiation Oncology, St Jude Children's Research Hospital, Memphis, 
      Tennessee, USA.
LA  - eng
PT  - Journal Article
DEP - 20230503
PL  - United States
TA  - J Appl Clin Med Phys
JT  - Journal of applied clinical medical physics
JID - 101089176
RN  - 059QF0KO0R (Water)
SB  - IM
MH  - Humans
MH  - Radiation Dosage
MH  - *Tomography, X-Ray Computed/methods
MH  - *Radiometry/methods
MH  - Phantoms, Imaging
MH  - Water
MH  - Risk Assessment
PMC - PMC10243315
OTO - NOTNLM
OT  - CT
OT  - SSDE
OT  - localizer
OT  - water-equivalent diameter
COIS- The authors declare no conflicts of interest.
EDAT- 2023/05/03 06:42
MHDA- 2023/06/08 06:42
PMCR- 2023/05/03
CRDT- 2023/05/03 03:52
PHST- 2023/02/24 00:00 [revised]
PHST- 2022/10/25 00:00 [received]
PHST- 2023/03/27 00:00 [accepted]
PHST- 2023/06/08 06:42 [medline]
PHST- 2023/05/03 06:42 [pubmed]
PHST- 2023/05/03 03:52 [entrez]
PHST- 2023/05/03 00:00 [pmc-release]
AID - ACM213989 [pii]
AID - 10.1002/acm2.13989 [doi]
PST - ppublish
SO  - J Appl Clin Med Phys. 2023 Jun;24(6):e13989. doi: 10.1002/acm2.13989. Epub 2023 
      May 3.