Endoluminal high-resolution MR imaging protocol for colon walls analysis in a mouse model of colitis
An endoluminal magnetic resonance (MR) imaging protocol including the design of an endoluminal coil (EC) was defined for high-spatial-resolution MR imaging of mice gastrointestinal walls at 4.7 T.
Materials and methods
A receive-only radiofrequency single-loop coil was developed for mice colon wall imaging. Combined with a specific protocol, the prototype was first characterized in vitro on phantoms and on vegetables. Signal-to-noise ratio (SNR) profiles were compared with a quadrature volume birdcage coil (QVBC). Endoluminal MR imaging protocol combined with the EC was assessed in vivo on mice.
The SNR measured close to the coil is significantly higher (10 times and up to 3 mm of the EC center) than the SNR measured with the QVBC. The gain in SNR can be used to reduce the in-plane pixel size up to 39 × 39 µm2 (234 µm slice thickness) without time penalty. The different colon wall layers can only be distinguished on images acquired with the EC.
Dedicated EC provides suitable images for the assessment of mice colon wall layers. This proof of concept provides gains in spatial resolution and leads to adequate protocols for the assessment of human colorectal cancer, and can now be used as a new imaging tool for a better understanding of the pathology.
KeywordsColorectal neoplasms Magnetic resonance imaging Colitis Instrumentation
This work was supported by the LABEX PRIMES (ANR-11-LABX-0063) of “Université de Lyon”, within the program “Investissements d’Avenir” (ANR-11-IDEX-0007) operated by the French National Research Agency (ANR).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflicts of interest.
Research involving animals
All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. All procedures performed in studies involving animals were in accordance with the ethical standards of the institution or practice at which the studies were conducted.
This study was approved by the institutional review board of the Université Claude Bernard Lyon 1 (reference number: DR2014-62-v1) and complied with ethics committee standards.
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