PT  - JOURNAL ARTICLE
AU  - Makoto Ohba
AU  - Yasuaki Kokubo
AU  - Koji Suzuki
AU  - Masafumi Kanoto
AU  - Yukihiko Sonoda
TI  - Influence of a Headrest on Reconstruction and Attenuation Correction of Human Brain SPECT Images
AID  - 10.2967/jnmt.120.244731
DP  - 2021 Mar 01
TA  - Journal of Nuclear Medicine Technology
PG  - 54--57
VI  - 49
IP  - 1
4099  - http://tech.snmjournals.org/content/49/1/54.short
4100  - http://tech.snmjournals.org/content/49/1/54.full
SO  - J. Nucl. Med. Technol.2021 Mar 01; 49
AB  - Previous reports suggest that a headrest significantly influences anterior and posterior cerebral blood flow. The present study aimed to clarify the influence of a headrest on reconstruction and attenuation correction (AC) of brain SPECT images. Methods: We evaluated the influence on cerebral blood flow in the anterior region (brain segments A + B), middle region (segments D + F), and posterior region (segment G) of the brain using filtered backprojection–AC based on the method of Chang (FBP-ChangAC), ordered-subset expectation maximization–ChangAC (OSEM-ChangAC), OSEM CT-based AC (OSEM-CTAC), and OSEM with no attenuation correction (OSEM-NoAC) with and without a headrest. The subjects were 17 healthy volunteers who underwent 99mTc-ECD SPECT. We compared the A + B/G and the D + F/G ratios of 99mTc-ECD SPECT images in each group. Results: For FBP-ChangAC, OSEM-ChangAC, and OSEM-NoAC, there were significant differences in A + B/G ratio between images obtained with a headrest and those obtained without. On the other hand, for OSEM-CTAC, there were no significant differences in A + B/G ratio regardless of whether a headrest was used. For FBP-ChangAC and OSEM-NoAC, there were significant differences in D + F/G ratio between images with a headrest and those without. For OSEM-CTAC and OSEM-ChangAC, there were no significant differences in D + F/G ratio regardless of whether a headrest was used. Conclusion: The influence of a headrest on image reconstruction and AC should be considered if FBP-ChangAC, OSEM-ChangAC, or OSEM-NoAC is used but not if OSEM-CTAC is used.