Test-retest variability and reliability of <sup>123</sup>I-IBZM SPECT measurement of striatal dopamine D<inf>2</inf> receptor availability in healthy volunteers and influence of iterative reconstruction algorithms

Ana M. Catafau, Santiago Bullich, Mónica Danús, María M. Penengo, Albert Cot, Sergio Abanades, Magí Farré, Javier Pavía, Domènec Ros

Research output: Contribution to journalArticleResearchpeer-review

19 Citations (Scopus)

Abstract

Objective: 123I-IBZM single photon emission computed tomography (SPECT) is a widely used method to measure D2 receptor availability. However, test-retest variability and reliability have not been reported yet. This study aimed to further characterize 123I-IBZM SPECT in healthy volunteers (HVs), by assessing (1) pseudoequilibrium interval after bolus injection; (2) normal specific uptake ratio (SUR) values using filtered-backprojection (FBP); and the iterative reconstruction algorithm ordered-subsets expectation maximization (OSEM); (3) test-retest variability and reliability (intraclass correlation coefficient); and (4) influence of OSEM on test-retest variability and reliability. Methods: Ten HVs (Group A) were scanned twice 48 h apart for test-retest variability and reliability measurements, and n = 4 of them were sequentially scanned over time. Eighteen HVs (Group B) were scanned once at pseudoequilibrium. For reconstruction FBP was used. Test-retest scans were reconstructed in addition using OSEM. SPECT-MRI coregistration was used for region of interest drawing. Results: Pseudoequilibrium was achieved at 90 min postinjection (p.i.) and maintained until the end of the SPECT session (n = 4), and mean SUR at this time point was 0.96 ± 0.14 (Groups A + B, n = 28). Mean SUR at test was 0.96 ± 0.19 and at retest 0.94 ± 0.19 (Group A, n = 10). Using FBP, test-retest variability was (12.7 ± 9.6)% and reliability was 0.74. Using OSEM with 18 equivalent iterations, test-retest variability and reliability were improved to (6.5 ± 5.2)% and 0.84, respectively. Conclusions: 123I-IBZM SPECT imaging using the bolus injection and a single scan at 90 min p.i. is a reproducible method showing acceptable test-retest variability and reliability. Test-retest variability and reliability can be substantially improved using OSEM with 12-36 equivalent iterations. ©2007 Wiley-Liss, Inc.
Original languageEnglish
Pages (from-to)62-69
JournalSynapse
Volume62
Issue number1
DOIs
Publication statusPublished - 1 Jan 2008

Keywords

  • Filtered-backprojection
  • Ordered-subsets expectation maximization

Fingerprint Dive into the research topics of 'Test-retest variability and reliability of <sup>123</sup>I-IBZM SPECT measurement of striatal dopamine D<inf>2</inf> receptor availability in healthy volunteers and influence of iterative reconstruction algorithms'. Together they form a unique fingerprint.

Cite this