Effect of Contrast Agent Administration on Size-Specific Dose Estimates (SSDE) Calculations based on Water Equivalent Diameter in CT Head Examinations

Moh. Shofi Nur Utami; Heri Sutanto; Choirul Anam; Muharam Budi Laksono

doi:10.32628/IJSRST2183124

Authors

Moh. Shofi Nur Utami Department of Physics, Faculty of Science and Mathematics, Diponegoro University, Semarang, Indonesia
Heri Sutanto Department of Physics, Faculty of Science and Mathematics, Diponegoro University, Semarang, Indonesia
Choirul Anam Department of Physics, Faculty of Science and Mathematics, Diponegoro University, Semarang, Indonesia
Muharam Budi Laksono Department of Radiology, Rumah Sakit Umum Daerah Majalengka, Majalengka, Indonesia

DOI:

https://doi.org//10.32628/IJSRST2183124

Keywords:

CT Head, water-equivalent diameter, size-specific dose estimate.

Abstract

Size-specific dose estimate (SSDE) is dose metrics of computed tomography, to calculate SSDE we first calculate the patient's body size. In CT head examination, the head size is better to use water-equivalent diameter (Dw), because Dw considers tissue attenuation. CT Head examination with contrast agent increased patient attenuation and increased Dw. In this study, we observed the effect of contrast agent on the Dw value on the axial image of patients with CT head examination. A total of 96 patients underwent a CT Head examination with a contrast agent in the two CT scan modalities. 46 patients underwent CT Head examination with contrast agent using CT Scanner Toshiba Alexion 16 and 50 patients underwent CT Head examination with contrast agent using CT Scanner GE Medical System Optima CT660. Dw value is calculated automatically using IndoseCT version 20b. We compared the Dw pre-contrast and Dw post-contrast values with the two independent sample t-test statistical analysis. To consider the effect of changing Dw values on SSDE we normalized dose coefficient (NDC). We did not find a significant difference between Dw pre-contrast and Dw post-contrast. The P-value statistical analysis results for the CT Scanner Toshiba Alexion 16 and the CT Scanner GE Medical System Optima CT660 were 0.65 and 0.45. The NDC change in this study was below 20%. On CT Head examination, the Dw and SSDE pre-contrast values can be used to estimate the Dw and SSDE post-contrast values.

References

Lee KH, Lee JM, Moon SK, Baek Jh, Park JH, Flohr TG, Kim KW, Kim SJ, Han JK, Choi BI. Attenuation-based Automatic Tube Voltage Selection and Tube Current Modulation for Dose Reduction at Contrast-enhanced Liver CT. Radiology. 2012; 265: 437 – 447.
Shuaib W, Tiwana, MH, Chokshi FH, Johnson JO, Bedi H, Khosa F. Utility of CT head in the acute setting: value of contrast and non-contrast studies. Irish Journal of Medical Science. 2015; 184: 631 – 635.
Sahbaee P, Abadi E, Segras WP, Marin D, Nelson RC, Samei E. The Effect of Contrast Medium on Radiation Dose in CT: Part II – A Systemic Evaluation across 58 Patient Models1. Radiology. 2017; 283: 749 – 757.
Solberg TD, Iwamoto KS, Norman A. Calculation of radiation dose enhancement factors for dose enhancement therapy of brain tumors. Phys. Med. Biol. 1992;37:439 – 443.
Hricak H, Brenner DJ, Adelstein SJ, Frush DP, Hall EJ, Howell RW, McCollough CH, Mettler FA, Pearce MS, Suleiman OH, Thrall JH, Wagner LK. Managing radiation use in medical imaging: a multifaceted challenge. Radiology. 2011; 258: 889 – 905.
Turner AC, Zankl M, DeMarco JJ, Cagnon CC, Zhang D, Angel E, Cody DD, Stevens DM, McCollough CH, McNitt-Gray MF. The feasibility of a scanner-independent technique to estimate organ dose from MDCT scans: using CTDIvol to account for differences between scanners. Med. Phys. 2010; 37: 1816 – 1825.
Bauhs JA, Vrieze TF, Primak AN, Bruesewitz MR, McCollough CH. CT Dosimetry: Comparison of Measurement Techniques and Devices. Radiographics. 2008; 28: 245 – 253.
Wang J, Duan X, Christner JA, Leng S, Yu L, McCollough CH. Attenuation-based estimation of patient size for size-specific dose estimation in CT. Part I. Development and validation of methods using the CT image. Med. Phys. 2012; 39: 6764 – 6771.
Franck C, Vandenoorde C, Goethals I, Smeets P, Achten E, Verstraete K, Thierens Hm Bacher K. The role of Size-Specific Dose Estimate (SSDE) in patient-specific organ dose and cancer risk estimation in pediatric chest and abdominopelvic CT examinations. Eur. Radiol. 2016; 26(8); 2646 – 2655.
Huda W, Mettler FA. Volume CT dose index and dose-length product displayed during CT: What good are they?. Radiology. 2011; 258: 236 – 242.
McCollough CH, Leng S, Yu L, Cody DD, Boone JM, McNitt-Gray MF. CT dose index and patient dose: They are not the same thing. Radiology. 2011; 259: 311 – 316.
Larson DB, Wang LL, Podberesky DJ, Goske MJ. System for verifiable CT radiation dose optimization based on image quality. Part I. Optimization model. Radiology. 2013; 269: 167 – 176.
Larson DB, Malarik RJ, Hall SM, Podberesky DJ. System for verifiable CT radiation dose optimization based on image quality. Part II. Process control system. Radiology. 2013; 269: 177 – 185.
American Association of Physicists in Medicine. Report of AAPM TG 204: Size-specific dose estimates (SSDE) in pediatric and adult body CT examinations. AAPM. 2011: 1 – 22.
Brink JA and Morin RL. Size-specific Dose Estimation for CT: How Should It be Used and What Does It Mean?. Radiology. 2012; 265: 666 – 668.
Kalender WA. X-Ray Computed Tomography. Phys Med Biol. 2014; 51: R29 – R43.
American Association of Physicists in Medicine. Report of AAPM TG 220: Use of water equivalent diameter for calculating patient size and size-specific dose estimates (SSDE). AAPM. 2014: 1 – 23.
Moore BM, Brady SL, Mirro AE, Kaufman RA. Size-specific dose estimate (SSDE) provides a simple method to calculate organ dose for pediatric CT examinations. Med. Phys. 2014; 41(7): 1 – 10.
American Association of Physicists in Medicine. Report of AAPM TG 293: Size-Specific Dose Estimate (SSDE) for Head CT. AAPM. 2019: 1 – 24.
Viggiano B, Rose S, Szczykutowicz TP. Effect of contrast agent administration on water equivalent diameter in CT. Med. Phys. 2021; 48: 1117 – 1124.
Nitasari A, Anam C, Budi WS, Wati AL, Syarifudin S, Dougherty G. Comparisons of water-equivalent diameter measured on images of abdominal routine computed tomography with and without contrast agent. Atom Indonesia. 2020.
Leng S, Shiung M, Duan X, Yu L, Zhang Y, McCollough CH. Size-specific dose estimates for chest, abdominal, and pelvic CT: effect of intrapatient variability in water-equivalent diameter. Radiology. 2015;276: 184 – 190.
Anam C, Haryanto F, Widita R, Arif I, Dougherty G. Automated Calculation of water equivalent diameter (Dw) based on AAPM Task Group 220. J Appl Clin Med Phys. 2016; 17(4): 320 – 333.
McCollough S, Moen T, Schneider J, Vrieze T, Leng S, McCollough C. Impact of Tube Potential On Water Equivalent Diameter and Size Specific Dose Estimate Values for Head, Chest, and Abdomen CT Scans, Mayo Clinic, Rochester, MN Presented at the 2019 AAPM Summer Meeting, San Antonio Texas, USA. https://doi.org/10.1002/mp.13596
Amato E, Salamone I, Naso S, Bottari A, Gaeta M, Blandino A. Can Contrast Media Increase Organ Doses in CT Examinations? A Clinical Study. AJR. 2013; 200: 1288 – 1293.
McCollough C, Bakalyar DM, Bostani M, et al. Use of water equivalent diameter for calculating patient size and size-specific dose estimates (SSDE) in CT: the report of AAPM task group 220. AAPM Report 2014; 2014: 6 – 23.
Yu L, Bruesewitz MR, Thomas KB, Fletcher JG, Kofler JM, McCollough CH. Optimal tube potential for radiation dose reduction in pediatric CT: principles, clinical implementations, and pitfalls. Radiographics. 2011; 31:835 – 848.