ABSTRACT
The purpose of this study was to investigate papilledema (PA) as a diagnostic criterion for the presence of antemortem or agonal cerebral edema despite normal postmortem brain swelling on postmortem magnetic resonance imaging (PMMR) in comparison with conventional autopsy.One hundred subjects with head PMMR and autopsy were included in this study. The sensitivities, spec icities, positive predictive values (PPVs), negative predictive values (NPVs), and accuracies were calculated in terms of the PA, PMMR, and cerebral edema on autopsy. Spearman r tests were used to analyze the linear correlations of PA and the radiological and autoptic determination of cerebral edema.In autopsy, the sensitivity regarding the presence of PA and cerebral edema was 66.2% (PPV, 70.5%), and specificity was 48.6% (NPV, 28.3%), with an overall accuracy of 60%. On PMMR, the sensitivity was 86.6% (PPV, 95%). The specificity was 90.9% (NPV, 34%), with an overall accuracy of 88%. The Spearman correlation revealed a statistically significant result (P < 0.001), which indicated a strong linear correlation of the presence of PA and cerebral edema with the autopsy results and the PMMR results.The presence of PA may aid in the diagnoses of cerebral edema despite normal postmortem brain swelling based on PMMR.
Subject(s)
Brain Edema/diagnosis , Magnetic Resonance Imaging , Papilledema/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Cause of Death , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Postmortem Changes , Predictive Value of Tests , Retrospective Studies , Sensitivity and Specificity , Young AdultABSTRACT
PURPOSE: The aim of the study was to evaluate contrast-enhanced MRI, diffusion-weighted MRI (DW MRI), and (68)Ga-DOTATATE positron emission tomography (PET)/CT in the detection of intermediate to well-differentiated neuroendocrine tumors (NET) of the pancreas. METHODS: Eighteen patients with pathologically proven pancreatic NET who underwent MRI including DW MRI and PET/CT within 6 weeks of each other were included in this retrospective study. Two radiologists evaluated T2-weighted (T2w), T2w + DW MRI, T2w + contrast-enhanced T1-weighted (CE T1w) MR images, and PET/CT for NET detection. The sensitivity and level of diagnostic confidence were compared among modalities using McNemar's test and a Wilcoxon signed rank test. Apparent diffusion coefficients (ADC) of pancreatic NETs and normal pancreatic tissue were compared with Student's t test. RESULTS: Of the NETs, 8/23 (34.8 %) and 9/23 (39.1 %) were detected on T2w images by observers 1 and 2, respectively. Detection rates improved significantly by combining T2w images with DW MRI (observer 1: 14/23 = 61 %; observer 2: 15/23 = 65.2 %; p < 0.05) or CE T1w images (observer 1: 14/23 = 61 %; observer 2: 15/23 = 65.2 %; p < 0.05). Detection rates of pancreatic NET with PET/CT (both observers: 23/23 = 100 %) were statistically significantly higher than with MRI (p < 0.05). The mean ADC value of NET (1.02 ± 0.26 × 10(-3) mm(2)/s) was statistically significantly lower than that of normal pancreatic tissue (1.48 ± 0.39 × 10(-3) mm(2)/s). CONCLUSION: DW MRI is a valuable adjunct to T2w imaging and comparable to CE T1w imaging in pancreatic NET detection, quantitatively differentiating between NET and normal pancreatic tissue with ADC measurements. (68)Ga-DOTATATE PET/CT is more sensitive than MRI in the detection of pancreatic NET.
