Home › Research › Digital health tools
Reducing between scanner differences in multi-center PET studies
Joshi A, Koeppe RA, Fessler JA.. NeuroImage, 2009-02-06
Topic: Risk, prevention and care in population studies
This work is part of the multi-center Alzheimer's Disease Neuroimaging Initiative (ADNI), a large multi-site study of dementia, including patients having mild cognitive impairment (MCI), probable Alzheimer's disease (AD), as well as healthy elderly controls. A major portion of ADNI involves the use of [(18)F]-fluorodeoxyglucose (FDG) with positron emission tomography (PET). The objective of this paper is the reduction of inter-scanner differences in the FDG-PET scans obtained from the 50 participating PET centers having fifteen different scanner models. In spite of a standardized imaging protocol, systematic inter-scanner variability in PET images from various sites is observed primarily due to differences in scanner resolution, reconstruction techniques, and different implementations of scatter and attenuation corrections. Two correction steps were developed by comparison of 3-D Hoffman brain phantom scans with the 'gold standard' digital 3-D Hoffman brain phantom: i) high frequency correction; where a smoothing kernel for each scanner model was estimated to smooth all images to a common resolution and ii) low frequency correction; where smooth affine correction factors were obtained to reduce the attenuation and scatter correction errors. For the phantom data, the high frequency correction reduced the variability by 20%-50% and the low frequency correction further reduced the differences by another 20%-25%. Correction factors obtained from phantom studies were applied to 95 scans from normal control subjects obtained from the participating sites. The high frequency correction reduced differences similar to the phantom studies. However, the low frequency correction did not further reduce differences; hence further refinement of the procedure is necessary.
Key findings
- Two correction steps were developed by comparison of 3-D Hoffman brain phantom scans with the 'gold standard' digital 3-D Hoffman brain phantom: i) high frequency correction; where a smoothing kernel for each scanner model was estimated to smooth all images to a common resolution and ii) low frequency correction; where smooth affine correction factors were obtained to reduce the attenuation and scatter correction errors.
- For the phantom data, the high frequency correction reduced the variability by 20%-50% and the low frequency correction further reduced the differences by another 20%-25%.
- Correction factors obtained from phantom studies were applied to 95 scans from normal control subjects obtained from the participating sites.
- The high frequency correction reduced differences similar to the phantom studies.
- However, the low frequency correction did not further reduce differences; hence further refinement of the procedure is necessary.
Why it matters
This methods study developed two correction steps to reduce inter-scanner differences in FDG-PET scans across 50 PET centers, reducing variability in phantom data. It is a technical imaging study and does not test any treatment, cure, or prevention for Alzheimer's disease.
New to this subject? Start with our plain-English guide: Digital health →
Study details
- Evidence strengthLow
How this study scored 49/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (NeuroImage) |
| Journal's citation record | 4 / 4 | NeuroImage: journal h-index 523 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2009 — within 20 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 5 / 7 | Cited 247 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 13.0 citations a year over 19 year(s) since 2009 |
| Impact for its field and year | 3 / 6 | Cited 4.7× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 18 other studies in this library |
| Still being cited | 3 / 4 | Cited 51 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author Jeffrey A. Fessler: h-index 72 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | University of Michigan: institution h-index 2,240 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | PubMed indexes it as a multicentre study |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 19457369) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 49 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
- DOI: 10.1016/j.neuroimage.2009.01.057
- PubMed: 19457369
- Original source →
- Free full text: PubMed Central →
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Joshi, A., Koeppe, R. A., & Fessler, J. A. (2009). Reducing between scanner differences in multi-center PET studies. NeuroImage. https://doi.org/10.1016/j.neuroimage.2009.01.057
Vancouver
Joshi A, Koeppe RA, Fessler JA. Reducing between scanner differences in multi-center PET studies. NeuroImage. 2009. doi:10.1016/j.neuroimage.2009.01.057. PMID: 19457369.
BibTeX
@article{joshi2009-19457369,
author = {Joshi, A. and Koeppe, R. A. and Fessler, J. A.},
title = {{Reducing between scanner differences in multi-center PET studies}},
journal = {NeuroImage},
year = {2009},
doi = {10.1016/j.neuroimage.2009.01.057},
pmid = {19457369},
url = {https://doi.org/10.1016/j.neuroimage.2009.01.057}
}
Later studies that cite this one
18 studies in the alzhub library list this one in their references. Showing the 8 highest-scoring.
Related studies in Digital health tools
Also in Digital health tools
178 studies in the library are filed under Digital health tools with no topic tag they share with another; these are this study's neighbours in a fixed tour of them. The Digital health tools hub.