[Radiation exposure of the patient caused by transmission measurement for myocardial perfusion SPECT].
OBJECTIVE
The aim was the determination of the radiation exposure to the patient caused by the transmission measurement for myocardial perfusion SPECT.


METHODS
Beside the emission measurement (Tc-99m-MIBI, A = 500 MBq) the myocardial perfusion SPECT simultaneously includes a transmission measurement using a Am-241-line source (A = 5550 MBq). During a simulation of the myocardial perfusion SPECT (without Tc-99m-MIBI) dose measurements with thermoluminescent dosimeters were carried out using a thorax phantom.


RESULTS
For an acquisition time of 20 min the absorbed doses amounted to: surface (xyphoid) 30 microGy, heart 25 microGy, lung 14 microGy, second thoracic vertebra 16 microGy, upper anterior mediastinum 16 microGy, liver 0 microGy. An estimation of the ratio of the effective doses caused by the transmission and the emission measurement of 3.6 x 10(-3) and 4.1 mSv, respectively, resulted in a value of 9 x 10(-4).


CONCLUSIONS
The radiation exposure of the patient caused by the transmission measurement can be neglected, and is therefore not a limiting factor regarding the general application of transmission measurement for clinical myocardial perfusion SPECT.
Seifert
H
H
Abteilung für Strahlentherapie, Universitätskliniken des Saarlandes, Homburg/Saar, Deutschland. rahsei@med-rz.uni-sb.de
Chapot
C
C
Schaefer
A
A
Donsch
P
P
Kirsch
C M
CM
D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D019047:Phantoms, Imaging; D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi; D013819:Thermoluminescent Dosimetry / Q000295:instrumentation* / Q000379:methods*; D015899:Tomography, Emission-Computed, Single-Photon / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*
D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi