ULTRASONOGRAPHY AND MR IMAGING IN PROGRESSIVE SUPRANUCLEAR PALSY William Liboni, Piero Pignatta, Elisabetta Salzedo, Sara Giordano, Filippo Molinari Bologna, 4-9 Oct 2010

Introduction Non-invasive detection and monitoring of movement disorders is the purpose of a clinician and neuroradiologist: for assessing markers useful to early diagnosis; to verify the progression of biological events. Up to now, conventional diagnostic tools for assessing the degeneration of substantia nigra (SN) and nigro-striatal pathways has proven inadequate due to their inability to diagnose the pathology before the onset of clear clinical pathological signs. Moreover, discrimination among idiopathic PD and atypical (ADP) Parkinsonism disorders in early stages is difficult: only 75% patients with PSP have correct probable diagnosis. The characteristic signs are at time challenging, since they have similar apparences. In most cases, the median interval between onset and diagnosis is 3 years.

Sample population age and sex matches MEN Subjects Age Subjects Sex WOMEN

Transcranial Sonography (TCS) and MRI MCA M BR SN A LN Third ventricle Standardized scanning planes (see Walter et al. UMB, 2007) TCS: low cost not invasive tool can asses Midbrain (M), Substantia Nigra (SN), Brainstem Raphe (BR), aqueduct (A), putaminal (LN).

DaTScan TCS Strio-nigratal degeneration - SN hyper-echogenicity A-PD Idiopathic PD A-PD PSP SN Hyperichogenicity: PD  95% almost all PSP  20% controls  12% LN Hyperichogenicity: PD  16% almost all PSP  80% controls  --%

Quantitative evaluation in conventional MRI MRPI = 28.2 In 2010 the same subject showed a MRPI = 48.4

(ADC-FA quantitative indices) Advanced MRI techniques: DTI (Diffusion Tensor Imaging) (ADC-FA quantitative indices) Regions-of-Interest (ROIs) M1 frontal lobe LN SN MCP SCP DTI-based tractography

Interval between symptoms onset and MRI investigation > 6 yrs 4<x<=6 yrs <=3 yrs 50% 17% 33%

MRI data comparison Regional ADC-FA values were calculated in each ROI. Median ADC and FA values were adapted as rapresentative indices of ADC and FA values. ADC index – median ± dev std FA index – median ± dev std ROI PSP PD MSA Controls Frontal lobe 0.88±0.002 0.83±0.03 0.84±0.009 0.8±0.03 Precentral gyrus 0.84±0.03 0.79±0.02 0.82±0.05 0.78±0.02 LN 0.84±0.02 0.78±0.03 0.84±0.05 0.76±0.001 SN 0.84±0.11 0.75±0.03 MCP 0.8±0.05 0.89±0.19 0.79±0.03 SCP 0.92±0.14 0.9±0.06 0.93±0.2 0.88±0.03 ROI PSP PD MSA Controls Frontal lobe 0.46±0.05 0.52±0.02 0.45±0.06 0.52±0.04 Precentral gyrus 0.48±0.03 0.49±0.03 0.47±0.03 0.52±0.03 LN 0.54±0.03 0.53±0.04 0.56±0.02 SN 0.58±0.02 0.6±0.03 0.58±0.09 0.62±0.02 MCP 0.58±0.03 0.59±0.02 0.56±0.08 SCP 0.53±0.007 0.58±0.001 0.53±0.0076 0.55±0.0005

Conclusions TCS is a low-cost diagnostic modality to assess mesencephalic and putaminal echogenicity (most likely reflecting iron not bound to ferritine) TCS discriminates between PD and PSP MRI is sensititve to biological and structural changes in movement disorders Conventional MRI has limited power in assessing early pathological stages Computer quantitative analysis can help clinicians in discriminating between PD, MSA and PSP (Quattrone et al., Radiology, 2008) Diffusion MRI using ADC-FA values modification, in selected areas characteristic of pathology involvement, could discriminate bewteen healthy and Parkinsonism, and, further, could discriminate between PD and PSP (and possibly MSA) Our pilot study demonstrates the possibility of obtaining indicative descriptors of the presence and the progression of the pathology TCS is a very repeatable and low-cost techniques; MR at 1.5T is relatively diffused and accessible to population and with overall costs compatible with mass screening.