Dm. Toma et al., Influence of arm positioning on rest/stress technetium-99m labeled sestamibi tomographic myocardial perfusion imaging, J NUCL CARD, 6(2), 1999, pp. 163-168
Background. Single photon emission computed tomography (SPECT) myocardial p
erfusion imaging (MPI) is routinely performed with patients' arms positione
d above their heads to avoid potential attenuation artifact and reduced ima
ge quality. Currently no data are available to support the use of this prac
tice using Tc-99m SPECT MPI.
Methods and Results. Forty-one patients referred for routine rest/stress MP
I were imaged using the standard protocol with arms positioned above their
heads and again with their arms at their sides. The patients were injected
with 10 to 45 mCi (370 to 1665 MBq) of Tc-99m-labeled sestamibi (Tc-99m-ses
tamibi), and SPECT images were acquired 30 to 90 minutes later. Thirty pati
ents were imaged on an ADAC Vertex dual-head camera and 11 patients on an A
DAC Cirrus single-head camera. Images were interpreted by 3 nuclear cardiol
ogists without knowledge of patient identity, arm position, or camera type
using a 17-segment scoring model, No significant differences were noted in
the percentage of abnormal study results, reversibility extent, or location
of MPI defects between the 2 arm positions in the same patients. Image qua
lity was also similar.
Conclusion. Arm positioning does not influence the interpretation of 99mTc-
sestamibi SPECT myocardial perfusion imaging with regard to image quality o
r defect location and extent.