Deep learning-based differentiation of peripheral high-flow and low-flow vascular malformations in T2-weighted short tau inversion recovery MRI.

BACKGROUND: Differentiation of high-flow from low-flow vascular malformations (VMs) is crucial for therapeutic management of this orphan disease. OBJECTIVE: A convolutional neural network (CNN) was evaluated for differentiation of peripheral vascular malformations (VMs) on T2-weighted short tau inversion recovery (STIR) MRI. METHODS: 527 MRIs (386 low-flow and 141 high-flow VMs) were randomly divided into training, validation and test set for this single-center study. 1) Results of the CNN's diagnostic performance were compared with that of two expert and four junior radiologists. 2) The influence of CNN's prediction on the radiologists' performance and diagnostic certainty was evaluated. 3) Junior radiologists' performance after self-training was compared with that of the CNN. RESULTS: Compared with the expert radiologists the CNN achieved similar accuracy (92% vs. 97%, p = 0.11), sensitivity (80% vs. 93%, p = 0.16) and specificity (97% vs. 100%, p = 0.50). In comparison to the junior radiologists, the CNN had a higher specificity and accuracy (97% vs. 80%, p < 0.001; 92% vs. 77%, p < 0.001). CNN assistance had no significant influence on their diagnostic performance and certainty. After self-training, the junior radiologists' specificity and accuracy improved and were comparable to that of the CNN. CONCLUSIONS: Diagnostic performance of the CNN for differentiating high-flow from low-flow VM was comparable to that of expert radiologists. CNN did not significantly improve the simulated daily practice of junior radiologists, self-training was more effective.

Comparison of Treponema-specific immunoglobulin G (IgG) index with Treponema pallidum particle agglutination (TPPA) index for detection of intrathecal Treponema-specific antibody synthesis for serological diagnosis of neurosyphilis.

The determination of Treponema-specific intrathecal immunoglobulin synthesis with the Treponema pallidum particle agglutination (TPPA) index is a well-established method recommended in German guidelines for the diagnosis of neurosyphilis. However, the TPPA test is no longer available. The aim of this study was to evaluate whether the determination of a Treponema-specific immunoglobulin G (IgG) index can substitute the TPPA index. Serum and cerebrospinal fluid (CSF) samples from patients with confirmed (n=6) and probable (n=3) neurosyphilis as well as patients with adequately treated syphilis without neurosyphilis (n=4) were investigated. In addition to index calculation further CSF parameters were determined. The results of the Treponema IgG and the TPPA index were consistent in all patients with confirmed neurosyphilis and non-neurosyphilis patients. In two patients with probable neurosyphilis the IgG index appeared more plausible than the TPPA index when taking into account all available laboratory and clinical data of the patients. In conclusion, the determination of Treponema-specific intrathecal immunoglobulin synthesis with the IgG index appears to be a suitable alternative to the TPPA index.

Quantification of contrast agent uptake in the hepatobiliary phase helps to differentiate hepatocellular carcinoma grade.

This study aimed to assess the degree of differentiation of hepatocellular carcinoma (HCC) using Gd-EOB-DTPA-assisted magnetic resonance imaging (MRI) with T1 relaxometry. Thirty-three solitary HCC lesions were included in this retrospective study. This study's inclusion criteria were preoperative Gd-EOB-DTPA-assisted MRI of the liver and a histopathological evaluation after hepatic tumor resection. T1 maps of the liver were evaluated to determine the T1 relaxation time and reduction rate between the native phase and hepatobiliary phase (HBP) in liver lesions. These findings were correlated with the histopathologically determined degree of HCC differentiation (G1, well-differentiated; G2, moderately differentiated; G3, poorly differentiated). There was no significant difference between well-differentiated (950.2 ± 140.2 ms) and moderately/poorly differentiated (1009.4 ± 202.0 ms) HCCs in the native T1 maps. After contrast medium administration, a significant difference (p ≤ 0.001) in the mean T1 relaxation time in the HBP was found between well-differentiated (555.4 ± 140.2 ms) and moderately/poorly differentiated (750.9 ± 146.4 ms) HCCs. For well-differentiated HCCs, the reduction rate in the T1 time was significantly higher at 0.40 ± 0.15 than for moderately/poorly differentiated HCCs (0.25 ± 0.07; p = 0.006). In conclusion this study suggests that the uptake of Gd-EOB-DTPA in HCCs is correlated with tumor grade. Thus, Gd-EOB-DTPA-assisted T1 relaxometry can help to further differentiation of HCC.

Impact of Surgical Evaluation of Additional Cine Magnetic Resonance Imaging for Advanced Thymoma with Infiltration of Adjacent Structures: The Thoracic Surgeon's View.

Background Preoperative radiological assessment is important for clarification of surgical operability for advanced thymic tumors. Objective was to determine the feasibility of magnetic resonance imaging (MRI) with cine sequences for evaluation of cardiovascular tumor invasion. Patients and Methods This prospective study included patients with advanced thymoma, who underwent surgical resection. All patients received preoperative computed tomography (CT) scan and cine MRI. Results Tumor infiltration was surgically confirmed in the pericardium (n = 12), myocardium (n = 1), superior caval vein (SCV; n = 3), and aorta (n = 2). A macroscopic complete resection was possible in 10 patients, whereas 2 patients with aortic or myocardial tumor invasion had R2 resection. The positive predictive value (PPV) was 50% for cine MRI compared with 0% for CT scan regarding myocardial tumor infiltration. The PPV for tumor infiltration of the aorta was 50%, with a higher sensitivity for the CT scan (100 vs. 50%). Infiltration of the SCV could be detected slightly better with cine MRI (PPV 75 vs. 66.7%). Conclusion Cine MRI seems to improve the accuracy of preoperative staging of advanced thymoma regarding infiltration of cardiovascular structures and supports the surgical approach.

State of the art: diagnostic tools and innovative therapies for treatment of advanced thymoma and thymic carcinoma.

In this review article, state-of-the-art diagnostic tools and innovative treatments of thymoma and thymic carcinoma (TC) are described with special respect to advanced tumour stages. Complete surgical resection (R0) remains the standard therapeutic approach for almost all a priori resectable mediastinal tumours as defined by preoperative standard computed tomography (CT). If lymphoma or germ-cell tumours are differential diagnostic considerations, biopsy may be indicated. Resection status is the most important prognostic factor in thymoma and TC, followed by tumour stage. Advanced (Masaoka-Koga stage III and IVa) tumours require interdisciplinary therapy decisions based on distinctive findings of preoperative CT scan and ancillary investigations [magnetic resonance imaging (MRI)] to select cases for primary surgery or neoadjuvant strategies with optional secondary resection. In neoadjuvant settings, octreotide scans and histological evaluation of pretherapeutic needle biopsies may help to choose between somatostatin agonist/prednisolone regimens and neoadjuvant chemotherapy as first-line treatment. Finally, a multimodality treatment regime is recommended for advanced and unresectable thymic tumours. In conclusion, advanced stage thymoma and TC should preferably be treated in experienced centres in order to provide all modern diagnostic tools (imaging, histology) and innovative therapy techniques. Systemic and local (hyperthermic intrathoracic chemotherapy) medical treatments together with extended surgical resections have increased the therapeutic options in patients with advanced or recurrent thymoma and TC.

Acute necrotizing pancreatitis: laboratory, clinical, and imaging findings as predictors of patient outcome.

OBJECTIVE: In patients with acute necrotizing pancreatitis, we analyzed whether laboratory and clinical findings determined in the early phase of disease and morphologic features on contrast-enhanced CT (CECT) at the beginning of the late phase of disease are helpful in predicting patient outcome and whether CECT findings provide additional information in establishing prognosis compared with the laboratory and clinical findings. MATERIALS AND METHODS: A retrospective analysis of 99 patients with acute necrotizing pancreatitis was performed. Four laboratory variables (albumin, calcium, C-reactive protein, WBC count) and three clinical variables (Acute Physiology, Age, Chronic Health Evaluation [APACHE] II score; Simplified Acute Physiology Score [SAPS] II; persistent organ failure) were assessed. Five morphologic features on CECT including Balthazar grade and CT severity index were reviewed. The endpoints of patient outcome were peripancreatic or pancreatic infection, need for intervention, duration of organ failure, ICU and hospital stays, and death. Based on receiver operating characteristic curve analysis for infection, high-and low-risk groups for each prognostic variable were calculated and univariable and multivariable Cox regression analyses were carried out. RESULTS: In our study population of 99 patients (63 men, 36 women; median age, 52 years; age range, 18-84 years), 25 patients (25%) developed infection, 42 patients (42%) experienced organ failure, and 12 patients (12%) died. Regarding the laboratory and clinical variables, albumin level, APACHE II score, and particularly persistent organ failure were the strongest independent predictors of patient outcome. Regarding the imaging variables, Balthazar grade and a morphologic feature that takes the distribution of intrapancreatic necrosis into account were the strongest independent predictors. In the multivariable analysis of all studied variables, imaging variables were independent and strong predictors of patient outcome and provided additional information in establishing prognosis compared with clinical and laboratory findings. CONCLUSION: In patients with suspected or proven acute necrotizing pancreatitis, performing CECT at the beginning of the late phase of disease is recommended to identify patients at increased risk for adverse outcomes.

Assessing quantitative post-mortem changes in the gray matter of the human frontal cortex proteome by 2-D DIGE.

The number of proteomics studies concerning human brain samples has been increasing in recent years, in particular in the discovery of biomarkers for neurological diseases. The human brain samples are obtained from brain banks, which are interested in providing high quality human nervous tissue. In order to provide brain banks as well as scientists working in the proteomics field with measures for tissue quality, the critical factors after death, the effect of post-mortem interval (PMI) and storage temperature on the human brain proteome were investigated. This study was focused on the gray matter of the frontal cortex. The PMI was artificially prolonged from the time of autopsy (2 h after death) by storing samples at 4 degrees C or room temperature over 18, 24, and 48 h. The samples were analyzed by 2-D DIGE using a pH 4-7 gradient, revealing a time course of quantitative protein changes. The degradation of three proteins, peroxiredoxin-1, stathmin, and glial fibrillary acidic protein were further confirmed by Western-blot analysis. Proteins vulnerable to PMI were analyzed by the 2-D DIGE analysis of cortex samples from three donors, and were derived from a variety of functional groups, including metabolic, structural, stress response, antioxidants, synaptosomal, and neuronal proteins.