TY - JOUR T1 - Characterization of the FDOPA uptake of the brainstem and diencephalon in parkinsonian syndromes by PET / MRI JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1493 LP - 1493 VL - 60 IS - supplement 1 AU - Quentin Demonceau AU - Georges Demonceau AU - Vincent Lebon Y1 - 2019/05/01 UR - http://jnm.snmjournals.org/content/60/supplement_1/1493.abstract N2 - 1493Objectives: FDOPA PET / CT is commonly used for the investigation of dopaminergic denervation, the diagnosis being based on striatal uptake. But other brain structures, including monoaminergic neurons of the brainstem and diencephalon, metabolize FDOPA and are likely to be affected. Using the values ​​automatically generated by a homemade PET / MRI atlas, we looked for alterations in the FDOPA uptake in parkinsonian syndromes. We retrospectively selected 35 patients who underwent FDOPA PET / MRI examination, 15 with Parkinson's syndrome according to clinical and scintigraphic data, 20 others considered very unlikely to have this condition (the control group). Methods: The T1 images of each patient were registered on the T1 images of a model where 28 anatomical regions had been previously identified. The adjustment parameters were then applied to FDOPA images acquired 90 min after injection. In each region VOIs of different sizes were then generated: 1 voxel (1mm3), 27 voxels or a volume adapted to the size of the region to be studied. The mean SUV, alone or compared to that of the other regions, was used to distinguish the 2 groups, by the way of a Student's test. Results: The results were similar, using different sizes of VOIS. In the parkinsonian group, a significant reduction in SUV was observed in the substantia nigra (p = 0.008) and hypothalamus (p = 0.03). Furthermore subtracting the mean SUV of those regions from that of the pulvinar mildly increased their signification (resp. 0.0002 and 0,02). We did not observe any significant difference in the midbrain, the A8 zone, the reticular or the raphe nuclei. In the supratentorial area, the occipital region was unaffected too, in contrast to the striatum. The best discriminations between parkinsonian and control groups, obtained by combining the activities of the whole regions, were provided by the difference between the SUV of, on the one hand, the putamen and, on the other hand, the pulvinar and the A8 area (both with p less than 10-8). Conclusions: For the first time in nuclear medicine, we think we have been able to automatically demonstrate the involvement of nuclei of the brainstem and diencephalon in Parkinson's syndrome. This opens perspectives in terms of early detection, staging and differential diagnosis of this disease. ER -