Analysis of plain X-ray and low resolution CT gonad dose arising from supplementary imaging after bone scanning

Kelly, J; Szczepura, K; Hogg, P; Tootell, AK

Abstract

Introduction:Bone scintigraphy has long been the first stop for patients undergoing
investigation of bone metastases. The procedure is recognised as being highly
sensitive to the disease however this corresponds to a low specificity. As a result
supplementary imaging to characterise and localise lesions is often required to aid
definitive diagnosis. There is a range of modalities that can be utilised for this
purpose including computed radiography (CR) digital radiography (DR),
multidetector computed tomography (MCDT) or CT acquisition using hybrid SPECTCT systems.The choice of modality has implications for patient dose, and therefore
careful justification of the chosen procedure is required. The reproductive organs
are recognised as radiosensitive, and so dose to these organs needs to be
considered.Aim:To compare the absorbed dose by the male and female
reproductive organs when imaging the lumbar spine using local protocols in CR, DR,
CT component of a SPECT-CT scanner and MDCT.Method:An ATOM 701-D
dosimetry phantom and calibrated thermoluminescent dosimeters (TLD) were
subjected to radiographic examinations of the lumbar spine using standard
department protocols. The TLDs were positioned within the phantom to measure
the absorbed dose of the ovaries and testes. Using three repeated measures,
antero-posterior and left lateral lumbar spine radiographs were acquired using
local diagnostic reference levels on CR and DR technology. CT Imaging of the
lumbar spine was carried out using a GE Infinia Hawkeye gamma camera and a GE
Lightspeed 64 CT scanner. The TLDs were read using a Hardshaw 3500 manual TLD
reader 24 hours after acquisition.Results:The absorbed dose to the ovaries was
found to be: DR 6.6mGy; CR 4.4mGy; MDCT 7.1mGy; hybrid CT 3.6mGy (p<0.05)The
absorbed dose to the testes was found to be: DR 8.1mGy; CR 4.9mGy; MDCT
4.0mGy; hybrid CT 1.7mGy (p>0.05)Comparison of results using ANNOVA found
that the organ dose from the different modalities were significantly different for
females, but not for males. Numerical comparison of the results demonstrates that
the hybrid CT acquisition resulted in a lower absorbed dose compared to the other
modalities for both males and females.Conclusion:This research demonstrates that
the dose from the CT component of the hybrid scanner results in the lowest
absorbed dose to the reproductive organs. However, surprisingly, the dose to the
testes from DR was found to be the highest dose.

Citation

Kelly, J., Szczepura, K., Hogg, P., & Tootell, A. (2011). Analysis of plain X-ray and low resolution CT gonad dose arising from supplementary imaging after bone scanning. European Journal of Nuclear Medicine and Molecular Imaging, 38(Sup. 2), S445. https://doi.org/10.1007/s00259-011-1913-y

• Journal Article Type: Conference Paper
• Conference Name: European Association of Nuclear Medicine (EANM) 2011
• Conference Location: Birmingham, UK
• End Date: Oct 19, 2011
• Publication Date: Sep 24, 2011
• Deposit Date: Feb 26, 2021
• Journal: European Journal of Nuclear Medicine and Molecular Imaging
• Print ISSN: 1619-7070
• Electronic ISSN: 1619-7089
• Publisher: Springer Verlag
• Volume: 38
• Issue: Sup. 2
• Pages: S445
• DOI: https://doi.org/10.1007/s00259-011-1913-y
• Publisher URL: https://doi.org/10.1007/s00259-011-1913-y
• Related Public URLs: http://link.springer.com/journal/259
• Additional Information: Event Type : Conference