PMID- 3488528
OWN - NLM
STAT- MEDLINE
DCOM- 19860916
LR  - 20190903
IS  - 0143-3636 (Print)
IS  - 0143-3636 (Linking)
VI  - 7
IP  - 5
DP  - 1986 May
TI  - Effects of centre-of-rotation shift on contrast and spatial resolution of the 
      SPECT system.
PG  - 373-9
AB  - The effects of centre-of-rotation (COR) shift of the rotating camera-based single 
      photon emission commuted tomography (SPECT) system on tomographic images were 
      investigated quantitatively. Contrast and spatial resolution variations as a 
      function of COR shift were measured for all shifts less than 1 pixel, in steps of 
      0.1 pixels. This region encompasses the typical COR variations. The behaviour of 
      these indices was analysed. In addition, the validity of the limit imposed on the 
      allowable COR shift, as utilized in the current SPECT quality control protocols, 
      was examined. The value of either +/- 0.5 or +/- 0.25 pixels is presently in use 
      as the limit. From this study, both limits result in the loss of resolution. The 
      resolution loss will increase the uncertainties of volume and concentration 
      measurements. For a COR shift of 0.25 pixels, the spatial resolution loss is 
      approximately 5%. This small spatial resolution loss may not affect the 
      qualitative evaluation of tomographic images. However, any loss of resolution 
      should be avoided. For a COR shift of 0.1 pixels, there is no observed loss of 
      resolution. This value should be a desirable choice as the maximum allowable COR 
      shift since it ensures the optimum performance of the SPECT system.
FAU - Saw, C B
AU  - Saw CB
LA  - eng
PT  - Journal Article
PL  - England
TA  - Nucl Med Commun
JT  - Nuclear medicine communications
JID - 8201017
SB  - IM
MH  - *Rotation
MH  - *Tomography, Emission-Computed/instrumentation
EDAT- 1986/05/01 00:00
MHDA- 1986/05/01 00:01
CRDT- 1986/05/01 00:00
PHST- 1986/05/01 00:00 [pubmed]
PHST- 1986/05/01 00:01 [medline]
PHST- 1986/05/01 00:00 [entrez]
AID - 10.1097/00006231-198605000-00007 [doi]
PST - ppublish
SO  - Nucl Med Commun. 1986 May;7(5):373-9. doi: 10.1097/00006231-198605000-00007.