B Kogelman – STSM Report

Bauke Kogelman, Netherlands

Bauke Kogelman hosted by prof. Blamire and dr. Paola Porcari, Newcastle Magnetic Resonance Centre, Newcastle University

August to November  2014


Newcastle University (NCL) and Leiden University Medical Center (LUMC) are collaborating within the BIOMAGE-NMD project to validate and optimize diffusion MRI to assess muscle damage in pre-clinical models for Duchenne Muscle Dystrophy. Therefore I undertook a Short Term Scientific Mission with three aims:


Aim I: Compare scanner performances on both sides. To collaborate on diffusion MRI to assess muscle damage it is essential to have same similar scanner performance at both sites. Both sides are equipped with a preclinical 7T MRI. To ensure similar scanner performance, phantoms were scanned at both sides by a number of sequences. From the acquired data T1, T2 and diffusion weighted values were extracted and compared. Signal-to-Noise ratios were assessed. I was able to watch and see how the scanner worked and functioned and determined the similarities and differences in terms of sequence settings between our systems. Secondly diffusion sequences were compared at most basic level; gradients were compared and differences were identified.


Aim II: Establish a measurement and histology protocol for preclinical muscle MR-DTI measurements. I was able to see how DTI scans were obtained and how the preclinical model was positioned and monitored. Therefore I was able to determine that a similar setup can also be achieved in the LUMC. Working with dr. Paola Porcori, we discussed the end-points regarding histology. We determined which parameters from a histology viewpoint are of importance to assess diffusion parameters. We agreed on determining fiber size, area’s of de- en regeneration (necrosis) and cell permeability and to correlate the diffusion parameters to these parameters. The histology parameters will be determined based on Standard Operation Procedures DMD_M.1.2.001 and DMD_M.1.2.007 from the TREAT-NMD network (http://www.treat-nmd.eu)


Aim III: Receive training concerning the new novel MR-DTI schemes to assess muscle damage. University College London (UCL) is developing new MR-DTI schemes that are optimized to quantify muscle damage. These new schemes consist of different timings and diffusion weighted values for MR-DTI measurements. I received training concerning shimming and performing MR-DTI-scans. I watched and learned how shimming is performed in NLC. We discussed how to assess the shim quality and I determined that the used strategy is also feasible and comparable within our institution. We discussed diffusion weighted settings and strategies on how to set these parameters. In our collaboration we are going to perform MR-DTI scans were the diffusion times are longer then conventional and in this setting the imaging gradients are not negligible. We discussed strategies to handle the influences of these gradients.