High-field diffusion tensor imaging of median, tibial, and sural nerves in type 2 diabetes with morphometric analysis

Pušnik, Luka (author), Gabor, Aljoša (author), Radochová, Barbara (author), Janáček, Jiří (author), Saudek, František (author), Alibegović, Armin (author), Serša, Igor (author), Cvetko, Erika (author), Umek, Nejc (author), Snoj, Žiga (author)

Background and Purpose: The primary objective was to compare diffusion tensor imaging (DTI) scalar parameters of peripheral nerves between subjects with type 2 diabetes mellitus (T2DM) and those without diabetes. Secondarily, we aimed to correlate DTI scalar parameters with nerve morphometric properties. Methods: Median, tibial, and sural nerves were harvested from 34 male cadavers (17 T2DM, 17 nondiabetic). Each nerve was divided into three segments. The initial segment was scanned using 9.4 Tesla MRI system (three-dimensional pulsed-gradient spin-echo sequence). DTI scalars were calculated from region-average diffusion-weighted signals. Second segment was optically cleared, acquired with optical projection tomography (OPT), and analyzed for morphometrical properties. Toluidine-stained sections were prepared from last segment, and axon- and myelin-related properties were evaluated. Results: DTI scalar parameters of median and tibial nerves were comparable between the groups, while sural nerves of T2DM exhibited on average 41% higher mean diffusivity (MD) (p = 0.03), 38% higher radial diffusivity (RD) (p = 0.03), and 27% lower fractional anisotropy (FA) (p = 0.005). Significant differences in toluidine-evaluated parameters of sural nerves were observed between the groups, with a positive correlation between FA with fiber density (p = 0.0001) and with myelin proportion (p < 0.0001) and an inverse correlation between RD and myelin proportion (p = 0.003). OPT-measured morphometric properties did not correlate with DTI scalar parameters. Conclusions: High-field DTI shows promise as an imaging technique for detecting axonal and myelin-related changes in small sural nerves ex vivo. The reduced fiber density and decreased myelin content, which can be observed in T2DM, likely contribute to observed FA reduction and increased MD/RD.

• Language: English
• Keywords: diffussion tensor, fractional anisotropy, histology, magnetic resonance imaging, microscopy, optical projection tomography
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: MF - Faculty of Medicine
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: 11 str.
• Numbering: Vol. 35, iss. 1, art. e70025
• PID: 20.500.12556/RUL-167756
• UDC: 616-07
• ISSN on article: 1552-6569
• DOI: 10.1111/jon.70025
• COBISS.SI-ID: 228292611
• Publication date in RUL: 10.03.2025

Record is a part of a journal

• Title: Journal of neuroimaging
• Publisher: Wiley, American Society of Neuroimaging
• ISSN: 1552-6569
• COBISS.SI-ID: 517766937

Licences

• License: CC BY-NC 4.0, Creative Commons Attribution-NonCommercial 4.0 International
• Link: http://creativecommons.org/licenses/by-nc/4.0/
• Description: A creative commons license that bans commercial use, but the users don’t have to license their derivative works on the same terms.

Secondary language

• Language: Slovenian
• Keywords: difuzijski tenzor, frakcijska anizotropija, histologija, slikanje z magnetno resonanco, mikroskopija, optična projekcijska tomografija