Optimizing Coronary Computed Tomography Angiography Using a Novel Deep Learning-Based Algorithm

Coronary computed tomography angiography (CCTA) is an essential part of the diagnosis of chronic coronary syndrome (CCS) in patients with low-to-intermediate pre-test probability. The minimum technical requirement is 64-row multidetector CT (64-MDCT), which is still frequently used, although it is prone to motion artifacts because of its limited temporal resolution and z-coverage. In this study, we evaluate the potential of a deep-learning-based motion correction algorithm (MCA) to eliminate these motion artifacts. 124 64-MDCT-acquired CCTA examinations with at least minor motion artifacts were included. Images were reconstructed using a conventional reconstruction algorithm (CA) and a MCA. Image quality (IQ), according to a 5-point Likert score, was evaluated per-segment, per-artery, and per-patient and was correlated with potentially disturbing factors (heart rate (HR), intra-cycle HR changes, BMI, age, and sex). Comparison was done by Wilcoxon-Signed-Rank test, and correlation by Spearman’s Rho. Per-patient, insufficient IQ decreased by 5.26%, and sufficient IQ increased by 9.66% with MCA. Per-artery, insufficient IQ of the right coronary artery (RCA) decreased by 18.18%, and sufficient IQ increased by 27.27%. Per-segment, insufficient IQ in segments 1 and 2 decreased by 11.51% and 24.78%, respectively, and sufficient IQ increased by 10.62% and 18.58%, respectively. Total artifacts per-artery decreased in the RCA from 3.11 ± 1.65 to 2.26 ± 1.52. HR dependence of RCA IQ decreased to intermediate correlation in images with MCA reconstruction. The applied MCA improves the IQ of 64-MDCT-acquired images and reduces the influence of HR on IQ, increasing 64-MDCT validity in the diagnosis of CCS

Wireless point-of-care ultrasound: First experiences with a new generation handheld device

AIM: To evaluate the diagnostic reliability of a new generation wireless point-of care ultrasound device for abdominal and thoracic findings. MATERIAL AND METHODS: 40 patients (16 females, 24 males 19 –80 years, on average 56.1 years) were scanned by an experienced examiner using the new wireless Vscan Air device for abdominal and thoracic findings. The probe frequencies were 2–5 MHz (convex probe) and 3–12 MHz for the linear probe. As a reference standard, all patients were also examined using high-end ultrasound (LOGIQ E9/LOGIQ E10). Results were interpreted independently by two examiners in consensus, also with regard to the image quality (0–4, from not assessable = 0, to excellent 4). RESULTS: In all 40 patients (100%) examination with conventional high-end ultrasound and the Vscan Air ultrasound device was feasible. Sensitivity, specificity, positive and negative predictive value for the diagnosis of abdominal and thoracic findings were 63.3%, 100%, 100%, and 40%, respectively. Most main diagnostic findings were detected using the mobile device compared to the high-end ultrasound. Limitations were found regarding characterization and classification of hepatic and renal tumorous lesions. Image quality revealed mostly minor diagnostic limitations for the mobile device, mean 2.9 (SD ± 0.300) and was excellent or with only minor diagnostic limitations for conventional high-end ultrasound, mean 3.25 (SD ± 0.438). CONCLUSION: Due to its easy application and its high diagnostic reliability, point-of-care ultrasound systems of the latest generation represent a valuable imaging method for the primary assessment of abdominal and thoracic findings, especially in patients on intensive care units or in emergency situations

Percutaneous Irreversible Electroporation: Long-term survival analysis of 71 patients with inoperable malignant hepatic tumors

Aim of this retrospective analysis was to evaluate the survival times after percutaneous irreversible electroporation (IRE) in inoperable liver tumors not amenable to thermal ablation. 71 patients (14 females, 57 males, median age 63.5 +/- 10.8 years) with 103 liver tumors were treated in 83 interventions using IRE (NanoKnife((R)) system). The median tumor short-axis diameter was 1.9 cm (minimum 0.4 cm, maximum 4.5 cm). 35 patients had primary liver tumors and 36 patients had liver metastases. The Kaplan-Meier method was employed to calculate the survival rates, and the different groups were compared using multivariate log-rank and Wilcoxon tests. The overall median survival time was 26.3 months; the median survival of patients with primary land secondary liver cancer did not significantly differ (26.8 vs. 19.9 months; p = 0.41). Patients with a tumor diameter > 3 cm (p < 0.001) or more than 2 lesions (p < 0.005) died significantly earlier than patients with smaller or fewer tumors. Patients with hepatocellular carcinoma and Child-Pugh class B or C cirrhosis died significantly earlier than patients with Child-Pugh class A (p < 0.05). Patients with very early stage HCC survived significantly longer than patients with early stage HCC with a median survival of 22.3 vs. 13.7 months (p < 0.05)

Diagnosis of pericardial effusion with a new generation hand-carried ultrasound device in cardiothoracic intensive care unit patients

Background: Technological advances introduced hand-carried ultrasound (HCU) imagers in daily clinical workflow providing several benefits such as fast bedside availability and prompt diagnosis. Purpose: To evaluate the diagnostic yield of a latest generation HCU imager compared to contrast-enhanced multidetector computed tomography (MDCT) for the detection of pericardial effusion (PE) in cardiothoracic intensive care unit (ICU) patients. Material and Methods: Thirty-six patients from a cardiothoracic ICU were enrolled to this study irrespective of their underlying disease. All patients were examined with a new generation HCU for the presence of PE. Definite diagnosis of PE was based on findings of MDCT as standard of reference. Statistical analysis was performed using PASW 18. Results: PE was identified in 20 patients by MDCT (prevalence 56%). The HCU examination was carried out technically successfully in all patients. Sensitivity, specificity, positive and negative predictive value of HCU for the diagnosis of PE were 75%, 88%, 88%, and 74%, respectively. Conclusion: HCU provides rapid, practical, reliable, and cost-effective diagnosis of PE in patients on cardiothoracic ICU

Influence of hepatic fibrosis and inflammation: Correlation between histopathological changes and Gd-EOB-DTPA-enhanced MR imaging

Objective To evaluate the influence of an active inflammatory process in the liver on Gd-EOB-DTPA-enhanced MR imaging in patients with different degrees of fibrosis/cirrhosis. Material and methods Overall, a number of 91 patients (61 men and 30 women; mean age 58 years) were included in this retrospective study. The inclusion criteria for this study were Gd-EOB-DTPA-enhanced MRI of the liver and histopathological evaluation of fibrotic and inflammatory changes. T1-weighted VIBE sequences of the liver with fat suppression were evaluated to determine the relative signal change (RE) between native and hepatobiliary phase (20 min). In simple and multiple linear regression analyses, the influence of liver fibrosis/cirrhosis (Ishak score) and the histopathological degree of hepatitis (Modified Hepatic Activity Index, mHAI) on RE were evaluated. Results RE decreased significantly with increasing liver fibrosis/cirrhosis (p < 0.001) and inflammation (mHAI, p = 0.004). In particular, a correlation between RE and periportal or periseptal boundary zone hepatitis (moth feeding necrosis, mHAI A, p = 0.001) and portal inflammation (mHAI D, p < 0.001) was observed. In multiple linear regression analysis, both the degree of inflammation and the degree of fibrosis were significant predictors for RE (p < 0.01). Conclusion The results of this study suggest that the MR-based hepatic enhancement index RE is not only influenced by the degree of fibrosis, but also by the degree of inflammation

Diet-Induced and Age-Related Changes in the Quadriceps Muscle: MRI and MRS in a Rat Model of Sarcopenia

Background: Knowledge about the molecular pathomechanisms of sarcopenia is still sparse, especially with regard to nutritional risk factors and the subtype of sarcopenic obesity. Objective: The aim of this study was to characterize diet-induced and age-related changes on the quality and quantity of the quadriceps muscle in a rat model of sarcopenia by different magnetic resonance (MR) techniques. Methods: A total of 36 6-month-old male Sprague-Dawley rats were randomly subdivided into 2 groups and received either a high-fat diet (HFD) or a control diet (CD). At the age of 16 months, 15 HFD and 18 CD rats underwent MR at 1.5 T. T1-weighted images as well as T2 relaxation time maps were acquired perpendicular to the long axis of the quadriceps muscles. Maximum cross-sectional area (CSA) of the quadriceps muscle was measured on T1-weighted images, and T2 relaxation times of muscle were assessed in a region without visible intramuscular fat (T2lean muscle) and across the complete CSA (T2muscle). Furthermore, 1H-MR spectroscopy was performed to evaluate the relative lipid content of the quadriceps muscles. These measurements were repeated 5 months later in the surviving 8 HFD and 14 CD rats. Results: HFD rats revealed significantly decreased CSA and CSA per body weight (BW) as well as prolonged T2 relaxation times of muscle. A higher weight gain (upper tertile during the first 6 months of diet in CD rats) resulted in a significant change of T2muscle, but had no relevant impact on CSA. Advancing age up to 21 months led to significantly decreased BW, CSA and CSA/BW, significantly prolonged T2muscle and T2lean muscle and enlarged lipid content in the quadriceps muscle. Conclusions: In an experimental setting a chronically fat-enriched diet was shown to have a relevant and age-associated influence on both muscle quantity and quality. By translational means the employed MR techniques give rise to the possibility of an early detection and noninvasive quantification of sarcopenia in humans, which is highly relevant for the field of geriatrics

Prognostic factors affecting survival after surgical resection of gastrointestinal stromal tumours: a two-unit experience over 10 years

BACKGROUND: Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal neoplasm of the gastrointestinal (GI) tract which has only been recently described based on their specific immunohistochemistry and the presence of particular KIT-related mutations which potentially make them targets for tyrosine kinase inhibition. METHODS: Sixty-one patients (29 M; 32 F, median age 60 years; range: 23–86 years) between June 1994 and March 2005, were analyzed from two allied institutions. Patient, tumour, and treatment variables were analyzed to identify factors affecting survival. RESULTS: Of the 61 patients, 55 (90%) underwent complete surgical resection of macroscopic disease. The 5-year overall survival (OS) rate in the 61 patients was 88% and the 5-year disease-free survival (DFS) in the 55 cases completely resected was 75%. Univariate analysis revealed that R0 resection was strongly associated with a better OSrate (p < 0.0001). Likewise, univariate analysis also showed high mitotic count of > 10 mitoses/per 50 HPF was a significant variable in worse prognosis for OS (≤ 10 mitoses/per 50 HPF 95% 5-year OS vs. > 10 mitoses/per 50 HPF 74% 5-year OS, respectively; p = 0.013). On subsequent multivariate analysis, only high mitotic count remained as a significant negative prognostic variable for OS (p = 0.029). Among patients resected for cure, there were 8 recurrences during follow-up. The mean time to recurrence was 21 ± 10 months (range: 4–36 months). Univariate analysis revealed that mitotic count of > 10 mitoses per 50 high power fields, intratumoural necrosis, and pathological tumour size (> 10 cm in maximal diameter) significantly correlated with DFS (p = 0.006, 0.002 and 0.02, respectively), with tumour necrosis and high mitotic count remaining as independent predictive variables affecting prognosis on subsequent multivariate analysis. CONCLUSION: Most GISTs are resectable with survival principally dependent upon mitotic count and completeness of resection. Future metabolic and genetic analyses will define the role of and resistance to induction or postoperative adjuvant targeted kinase inhibition therapy

Resection and local therapy for liver metastases

In 30–50% of patients the liver is a preferred site of distant disease for many malignant tumours. Due to the high incidence, most of the available data relate to metastases arising from colorectal primaries. Surgical resection is at present the only treatment offering potential cure. The achievable 5-year survival rate is 30%. However, only 10–15% of patients with colorectal liver metastases can undergo potentially curative liver resection. Therefore, accurate staging is an important prerequisite in selecting patients who would benefit from surgery. Recurrence of hepatic metastases after potentially curative resection occurs in up to 60% of the cases. Results demonstrate that re-resection of liver metastases can provide long-term survival rates in a carefully selected group of patients without extrahepatic disease. Because of the high rate of recurrences following an apparently curative resection several authors investigated the use of adjuvant chemotherapy (systemic, intraportal, and hepatic arterial infusion). Until recently none had shown effectiveness. Pre-operative chemotherapy seems to be a promising approach in patients with liver metastases initially considered unsuitable for radical surgery. Recently, neoadjuvant chemotherapy has been proposed as an alternative approach to conventional surgery as initial management with the aim of improving the results in resectable liver metastases. Interventional strategies (ethanol injection, cryosurgery, laser-induced thermotherapy, radio-frequency ablation) and combined modalities (surgical/interventional) are additive methods which may help to improve treatment results in the future

Contrast enhanced ultrasonography (CEUS) to detect abdominal microcirculatory disorders in severe cases of COVID-19 infection: First experience

In the hands of experienced examiners, the contrast enhanced sonography (CEUS) offers the possibility to analyze dynamic microcirculatory disturbances in real time dynamically without any risk for kidneys and thyroid gland even in severe progressing disease bedside. Based on severe COVID-19 infections, first experiences with abdominal CEUS examinations are presented. In the stage of an imminent organ failure with significantly reduced kidney and liver function, CEUS can be used to show a narrowing of the organ-supplying arteries, as well as a delayed capillary filling of vessels near the capsule, a regional reduced parenchymal perfusion or an inflammatory hyperemia with capillary hypercirculation. It is possible to quickly rule out organ infarction and to dynamically record the mesenteric arterial and venous blood flow