Assessment of radiation exposure caused by transmission scans in SPECT: an anthropomorphic dosimetry study

• Published in: Biomedizinische Technik Vol. 47 Suppl 1 Pt 1; p. 474
• Main Authors: Bellemann, M E, Riemann, S, Käpplinger, S, Brix, G, Gottschild, D
• Format: Journal Article
• Language: English; German
• Published: Germany 2002
• Subjects: Gadolinium; Head - radiation effects; Humans; Phantoms, Imaging; Radiation Dosage; Radioisotopes; Thermoluminescent Dosimetry; Tomography, Emission-Computed, Single-Photon
• ISSN: 0013-5585
• DOI: 10.1515/bmte.2002.47.s1a.474

Transmission measurements are performed in SPECT to correct for attenuation of the gamma quanta in the body. In this study, we measured the additional radiation dose caused by transmission scans using a field of collimated 153Gd rod sources. Two measurement series were performed with a anthropomorphic phantom and thermoluminescence dosimeters. For a typical SPECT study, we found a mean dose rate of 2.2 +/- 0.8 micro Sievert per hour (range: 1.2-3.9 micro Sievert per hour). For a measurement time of 20 min, this corresponds to a mean equivalent patient radiation dose of 0.73 micro Sievert. Thus, the radiation exposure caused by transmission scans can be neglected compared to the radiopharmaceutical dose and may not be considered as a limiting factor for the clinical application of attenuation correction in SPECT.