MRI of the locus coeruleus and substantia nigra Dr Timothy Rittman Academic Foundation Year 2
Substantia nigra Locus coeruleus
Imaging of SN
Sasaki et al
Effect of MT and SPIR
Magnetisation transfer Neuromelanin Macromolecules = short T2* Off resonance radiofrequency pulse Transfer of energy from macromolecules water ?iron SPIR presaturation pulse hidden MT effect
Method T1 MRI Repetition time 757ms Echo time 9.1ms Voxel size = 0.47x0.47x2.75mm3 SPIR 7 healthy volunteers MT not possible due to SAR limits
Results - Substantia nigra
Results - Locus coeruleus
Conclusion The substantia nigra and locus coeruleus are visible using T1 weighted imaging with SPIR Most likely due to an MT effect Sequence is sensitive to neuromelanin Specificity remains to be tested
Thanks to… Prof Auer All in Academic Radiology All at Sir Peter Mansfield Magnetic Resonance Centre Prof Mahida and Prof Hawkey