Objective: Our study retrospectively analyzed the clinical and imaging data of 42 consecutive  patients with PS whose diagnosis was uncertain at an early stage. The aim was to determine how MRI, integrated with early clinical evaluation, could help speed up and improve accuracy of the diagnosis.

Background: The emergence of disease modifying treatments for Parkinson’s disease (PD) or atypical parkinsonism , pushes towards an early and accurate diagnosis in patients with parkinsonian syndroms (PS).

Method: 42 consecutive patients were referred to a single movement disorders clinics (Paris, France). At baseline and after 2 years of follow up, brain MR imaging (MRI) and clinical assessment were performed in all patients. According to clinical consensus criteria, each patient was retrospectively classified as a probable or a possible case for PD, MSA, CBD or PSP. All the MRI scans were rated independently in a standardized manner, blinded to the diagnosis. In the absence of anatomical data, the silver standard diagnostic was the best movement disorders expert’s diagnosis after two years of follow up.

Results: Based on clinical criteria alone, our study showed a frequency of uncertain diagnosis (61%) at baseline that decreased at follow-up (44%). Based on MRI criteria at baseline, there was 58% of uncertain diagnosis. When mixing MRI and clinical criteria at baseline, we increased the certainty of 12% compared with clinical criteria alone. At baseline, when the diagnosis was uncertain with clinical criteria, MRI criteria refine or correct the diagnosis in 81% patients. The mean sensitivity and specificity of clinical criteria to diagnose MSA was, respectively, 86.5% and 54.5% whereas the sensitivity and specificity of MRI was 90.9% and 87.1%. The specificity of MRI was significantly higher than clinical criteria to diagnose MSA (p<0.001). There was no significant difference between sensitivity, specificity or PPV of MRI and clinical criteria for PD and PSP patients.

Conclusion: Our study shows the limitations of current clinical criteria for the diagnosis of atypical parkinsonian syndrome at early stage when the diagnosis is still uncertain. MRI could improve the differential diagnosis between MSA, PSP and PD but composite score or/and new markers are needed to improve the specificity and the sensibility of MRI criteria.

« Back to 2019 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/accuracy-of-clinical-diagnosis-of-atypical-parkinsonism-comparison-of-consensus-clinical-criteria-with-mri-criteria/