Evidence map›Paper›PMID 41672497›Full record

ArticleMagnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine2026

Effects of Postmortem Intervals on Quantitative MRI in Unfixed and Fixed Swine Brain: Implications for Ex Vivo MRI Applications.

Lixian Wang, Naoya Oishi, Shin-Ichi Urayama, Takashi Hanakawa

Abstract read
In one paragraph

Article in Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors.

Lixian WangHuman Brain Research Center, Graduate School of Medicine, Kyoto University, Kyoto Kyoto, Japan.
Naoya OishiHuman Brain Research Center, Graduate School of Medicine, Kyoto University, Kyoto Kyoto, Japan.
Shin-Ichi UrayamaHuman Brain Research Center, Graduate School of Medicine, Kyoto University, Kyoto Kyoto, Japan.
Takashi HanakawaHuman Brain Research Center, Graduate School of Medicine, Kyoto University, Kyoto Kyoto, Japan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeThe postmortem interval (PMI) alters tissue properties that shape quantitative MRI (qMRI) signals. We systematically investigated the effects of PMI on relaxation times, depending on tissue characteristics, in both unfixed and fixed pig brains.

methodsTwelve pig brains (n = 12) were scanned in both unfixed and fixed states at 3 PMI windows (≈12, 24, 48h). Quantitative T1, T2, and T2* maps were acquired with identical protocols at controlled room temperature (~24°C). We assessed the PMI effects on relaxation times in the gray matter (GM) and the white matter (WM) at both group and sample levels, while fixation-induced effects and inter-sample variability were evaluated using pairwise rank correlation and coefficient of variation (CV) visualization.

resultsIn unfixed tissues, T1 significantly differed among PMI groups in GM (P = 0.0141) and WM (P = 0.0315) in the early window (≤24h). In the same window, PMI-T1 correlations were observed in both GM (r = 0.921, P = 0.007) and WM (r = 0.876, P = 0.013). T2 showed no group differences but exhibited an inverse correlation with PMI in WM (r = -0.849, P = 0.015). No significant PMI-T2* relationships were detected (all P > 0.05). At later PMI (20-50h), PMI-qMRI correlations diminished. Fixation processes altered all qMRI parameters. Notably, the PMI effects on T1 in the unfixed brains were preserved even after fixation at an ordinal level, although fixation introduced substantial inter-sample variability.

conclusionPMI exerts the most robust effects on T1. Fixation has a significant impact on qMRI values, mitigating the apparent PMI effect and increasing the inter-sample variability. However, it is still possible to retrieve the PMI effects from fixed brain at the level of rank order, providing practical guidance for further ex vivo qMRI studies on PMI.

Indexed as

BrainMagnetic Resonance ImagingPostmortem ChangesAnimalsImage Processing, Computer-AssistedPostmortem ImagingSwineTime FactorsTissue FixationWhite Matterex vivo magnetic resonance imagingformalin fixationpostmortem intervalquantitative magnetic resonance imagingrelaxation properties

Identifiers

PMID41672497
PMCPMC13481156

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.