Contribution of the Mesencephalon Indices to Differential Diagnosis of Parkinsonian Disorders.

BACKGROUND AND PURPOSE: This study aimed to assess the sensitivity and specificity of brain stem morphologic changes to differentiate the progressive supranuclear palsy (PSP) from Parkinson disease (PD) and multiple system atrophy (MSA), by single and combined magnetic resonance imaging (MRI) measurements. MATERIALS AND METHODS: Peduncle angle (PA), pons area (P), mesencephalon area (M), middle cerebellar peduncles (MCPs), and superior cerebellar peduncles (SCPs) were measured in 14 PSP, 43 PD, 8 MSA patients, and 45 age-matched control participants on T1-weighted MRI. Neurologists clinically diagnosed all patients. Additionally, P/M ratio, MCPs/SCPs ratio, the previously defined Magnetic Resonance Parkinsonism Index, MRPI: (P/M) · (MCP/SCP), and also the Akdeniz Index (AKI) that we termed were calculated, AKI: (P/M) · (PA/180). Two blinded radiologists evaluated all MR images and inter-/intraobserver variations were measured. RESULTS: Both M and SCPs were significantly lower and P/M, MCPs/SCPs, and PA were significantly higher in PSP patients than the other groups (P < .001). This significance was related to patients with PSP and PD. But all single measurements showed some overlapping values. Therefore, previously defined MRPI was calculated and shown to distinguish patients (negative predictive values: 92%, sensitivity: 78%, specificity: 82%). In this study, interobserver correlation (0.68) was found low for MRPI. Therefore, we identified a more practical index: the Akdeniz Index, which has same diagnostic power with MRPI and higher interobserver correlation (0.91). CONCLUSION: The Akdeniz Index identified in our study is a practical index with high diagnostic power and can reinforce radiological distinguishing of PSP and PD, which are clinically difficult to distinguish.

Role of extrapancreatic necrosis volume in determining early prognosis in patients with acute pancreatitis.

PURPOSE: This study aims to evaluate the capacity of the clinical and radiological findings and the extrapancreatic necrotic tissue volume in early (2-6 days) computerized tomography (CT) images of patients diagnosed with AP to predict reliably the temporary or permanent organ failure and other local or systemic complications due to pancreatitis. MATERIALS AND METHODS: Adult patients who were diagnosed with AP based on Revised Atlanta classification and underwent abdomen CT scans between May 2015 and May 2018 were examined retrospectively. Extrapancreatic necrosis volume was compared to various clinical parameters that indicate the prognosis of AP such as C-reactive protein (CRP) at 48-72th h, organ failure, infection, requirement for percutaneous or surgical intervention, length of hospital stay, and mortality, and to various imaging-based scoring systems such as the computerized tomography severity index (CTSI) and the modified CTSI (mCTSI). The receiver operating characteristic (ROC) curve was used to estimate the optimal threshold for predicting clinical prognosis. RESULTS: Extrapancreatic necrosis volume had moderate positive correlation with length of hospital stay (p = 0.0001) and CRP (at 48-72th h) (p = 0.0001) and strong positive correlation with CTSI (p = 0.0001), mCTSI (p = 0.0001), and white blood cell count (p = 0.0001). CONCLUSION: Extrapancreatic necrosis volume was found to be particularly better in predicting organ failure and infection compared to the imaging-based scoring systems (Balthazar, CTSI, and mCTSI) and the laboratory-based scoring systems (CRP at 48-72th h).