: To evaluate the differences in treatment and outcomes between traumatic and atraumatic splenic lacerations. : This retrospective study included all patients with a diagnosis of splenic lacerations confirmed by computed tomography that presented from 01/2010 to 03/2023 at one tertiary hospital. The exclusion criteria included missing image data and death in the first 24 h due to extensive trauma.
View Article and Find Full Text PDF: Virtual non-contrast (VNC) series reconstructed from contrast-enhanced cardiac scans acquired with photon counting detector CT (PCD-CT) systems have the potential to replace true non-contrast (TNC) series. However, a quantitative comparison of the image characteristics of TNC and VNC data is necessary to determine to what extent they are interchangeable. This work quantitatively evaluates the image similarity between VNC and TNC reconstructions by measuring the stability of multi-class radiomics features extracted in intra-patient TNC and VNC reconstructions.
View Article and Find Full Text PDFBackground: The increased specificity of ultrahigh-resolution (UHR) photon-counting detector (PCD)-CT over energy-integrating detector (EID)-CT for coronary CT angiography (CCTA) could defer unwarranted downstream tests. The objective of the study was to simulate the cost-effectiveness of UHR CCTA in stable chest pain patients with coronary calcifications.
Methods: A decision and simulation model was developed using Monte Carlo simulations with 1000 bootstrap resamples to estimate the costs associated with PCD-CT in lieu of EID-CT for CCTA and the referral for subsequent testing.
Objectives: Introducing SPINEPS, a deep learning method for semantic and instance segmentation of 14 spinal structures (ten vertebra substructures, intervertebral discs, spinal cord, spinal canal, and sacrum) in whole-body sagittal T2-weighted turbo spin echo images.
Material And Methods: This local ethics committee-approved study utilized a public dataset (train/test 179/39 subjects, 137 female), a German National Cohort (NAKO) subset (train/test 1412/65 subjects, mean age 53, 694 female), and an in-house dataset (test 10 subjects, mean age 70, 5 female). SPINEPS is a semantic segmentation model, followed by a sliding window approach utilizing a second model to create instance masks from the semantic ones.
Purpose: To investigate the diagnostic performance of an automatic pipeline for detection of hydronephrosis on kidney's parenchyma on unenhanced low-dose CT of the abdomen.
Methods: This retrospective study included 95 patients with confirmed unilateral hydronephrosis in an unenhanced low-dose CT of the abdomen. Data were split into training (n = 67) and test (n = 28) cohorts.
Background: Photon-counting detector computed tomography (PCD-CT) is a groundbreaking technology with promising results for visualization of small bone structures.
Purpose: To analyze the delineation of the thoracic spine in multiplanar reconstructions (MPR) on PCD-CT compared to energy-integrating detector (EID)-CT.
Material And Methods: Two euthanized mice were examined using different scanners: (i) 20-slice EID-CT and (ii) dual-source PCD-CT at various CTDI values.
In the early diagnostic workup of acute pancreatitis (AP), the role of contrast-enhanced CT is to establish the diagnosis in uncertain cases, assess severity, and detect potential complications like necrosis, fluid collections, bleeding or portal vein thrombosis. The value of texture analysis/radiomics of medical images has rapidly increased during the past decade, and the main focus has been on oncological imaging and tumor classification. Previous studies assessed the value of radiomics for differentiating between malignancies and inflammatory diseases of the pancreas as well as for prediction of AP severity.
View Article and Find Full Text PDFBackground: Population-wide research on potential new imaging biomarkers of the kidney depends on accurate automated segmentation of the kidney and its compartments (cortex, medulla, and sinus).
Methods: We developed a robust deep-learning framework for kidney (sub-)segmentation based on a hierarchical, three-dimensional convolutional neural network (CNN) that was optimized for multiscale problems of combined localization and segmentation. We applied the CNN to abdominal magnetic resonance images from the population-based German National Cohort (NAKO) study.
Objectives: Aim of this study was to assess the value of virtual non-contrast (VNC) reconstructions in differentiating between adrenal adenomas and metastases on a photon-counting detector CT (PCD-CT).
Material And Methods: Patients with adrenal masses and contrast-enhanced CT scans in portal venous phase were included. Image reconstructions were performed, including conventional VNC (VNC) and PureCalcium VNC (VNC), as well as virtual monochromatic images (VMI, 40-90 keV) and iodine maps.
Purpose: The aim of this study was to evaluate the radiation dose, image quality, and the potential of virtual monoenergetic imaging (VMI) reconstructions of high-pitch computed tomography angiography (CTA) of the thoracoabdominal aorta on a dual-source photon-counting detector-CT (PCD-CT) in comparison with an energy-integrating detector-CT (EID-CT), with a special focus on low-contrast attenuation.
Methods: Consecutive patients being referred for an electrocardiogram (ECG)-gated, high-pitch CTA of the thoracoabdominal aorta prior to transcatheter aortic valve replacement (TAVR), and examined on the PCD-CT, were included in this prospective single-center study. For comparison, a retrospective patient group with ECG-gated, high-pitch CTA examinations of the thoracoabdominal aorta on EID-CT with a comparable scan protocol was matched for gender, body mass index, height, and age.
Purpose: To assess the reliability of virtual non-contrast (VNC) derived coronary artery calcium quantities in relation to heart rate and the VNC algorithm used compared to reference true non-contrast (TNC), considering several clinically established acquisition modes.
Material And Methods: An ad hoc built coronary phantom containing four calcified lesions and an iodinated lumen was scanned using three cardiac acquisition modes three times within an anthropomorphic cardiac motion phantom simulating different heart rates (0, 60, 80, 100 bpm) and reconstructed with a conventional (VNC) and a calcium-sensitive (VNC) VNC algorithm. TNC reference was scanned at 0 bpm with non-iodinated lumen.
The aim of our study was to evaluate two different virtual non-contrast (VNC) algorithms applied to photon counting detector (PCD)-CT data in terms of noise, effectiveness of contrast media subtraction and aortic valve calcium (AVC) scoring compared to reference true non-contrast (TNC)-based results. Consecutive patients underwent TAVR planning examination comprising a TNC scan, followed by a CTA of the heart. VNC series were reconstructed using a conventional (VNC) and a calcium-preserving (VNC) algorithm.
View Article and Find Full Text PDFIn this anthropomorphic head phantom study, samples containing blood and contrast agent with concentrations ranging from 0 to 6 mg iodine per milliliter and another set of samples without blood for reference were scanned with a photon-counting detector CT using a standard cranial protocol. It was demonstrated that photon-counting detector CT can reliably distinguish hemorrhage and contrast media, including density determination of the latter. The technology promises to add value in several neuroimaging applications.
View Article and Find Full Text PDFAim: The aims of this study were to analyse all hospitalizations for acute diverticulitis in Germany from 2010 to 2021 and to assess the effects of the first 2 years of the SARS-CoV-2 pandemic on hospitalizations for acute diverticulitis.
Method: Using data from the German Federal Statistical Office, we analysed fully anonymized healthcare data of hospitalizations and treatment regimens with acute diverticulitis as the main diagnosis between 2010 and 2021. Logistic regression analyses for in-hospital mortality were performed.
Objectives: Medical imaging plays an essential role in healthcare. As a diagnostic test, imaging is prone to substantial overuse and potential overdiagnosis, with dire consequences to patient outcomes and health care costs. Clinical decision support systems (CDSSs) were developed to guide referring physicians in making appropriate imaging decisions.
View Article and Find Full Text PDFPurpose: Aim of this study was to determine which virtual non-contrast (VNC) reconstruction algorithm, applied to which contrast phase of computed tomography angiography, best matches true non-contrast (TNC) images in the assessment of active bleeding.
Method: Patients who underwent a triphasic scan (pre-contrast, arterial, portal venous contrast) on a photon-counting detector CT (PCD-CT) (120 kV, image quality level 68) with suspected active (tumor, postoperative, spontaneous or other) bleeding were retrospectively included in this study. Conventional (VNC) and a calcium-preserving VNC algorithm (VNC) were derived from both arterial (art) and portal venous (pv) contrast scans, and analyzed quantitatively and qualitatively by two independent and blinded raters.
Purpose: To analyze the conspicuity of pancreatic ductal adenocarcinoma (PDAC) in virtual monoenergetic images (VMI) on a novel photon-counting detector CT (PCD-CT) in comparison to energy-integrating CT (EID-CT).
Methods: Inclusion criteria comprised initial diagnosis of PDAC (reference standard: histopathological analysis) and standardized contrast-enhanced CT imaging either on an EID-CT or a PCD-CT. Patients were excluded due to different histopathological diagnosis or missing tumor delineation on CT.
Purpose: To investigate differences in thermal sensitivity of virtual monoenergetic imaging (VMI) series generated from photon-counting detector (PCD) CT data sets, regarding their use to improve discrimination of the ablation zone during percutaneous cryoablation.
Materials And Methods: CT-guided cryoablation was performed using an ex vivo model of porcine liver on a PCD-CT system. The ablation zone was imaged continuously for 8 min by acquiring a CT scan every 5 s.
Background: Aim of this study was to analyze long-term trends of hospitalizations, treatment regimen and in-hospital mortality of in-patients with acute mesenteric ischemia (AMI) over the past decade and effects of the SARS-CoV2-pandemic.
Methods: We analyzed fully anonymized data from the German Federal Statistical Office of patients with AMI between 2010 and 2020. Besides descriptive analyses of age, gender, in-hospital mortality, comorbidity burden and treatment regimen, multivariable logistic regression analyses were performed to identify independent variables associated with in-hospital mortality and different treatment.
Purpose: Aim of this study was to analyze hospitalizations due to ruptured and non-ruptured abdominal aortic aneurysms (rAAA, nrAAA) in Germany between 2005 and 2021 to determine long-term trends in treatment and the impact of the SARS-CoV-2 pandemic.
Materials And Methods: Fully anonymized data were available from the research data center (RDC) of the German Federal Statistical Office (Destatis). All German hospitalizations with the ICD-10 code "I71.
Purpose: To correlate CT values of the blood pool on VNC series with serum hemoglobin values for the detection of anemia in oncologic patients undergoing contrast-enhanced PCD-CT scans.
Methods: This prospective study (NCT04989192) included consecutive oncologic patients undergoing contrast-enhanced CT on a novel PCD-CT system between 08/2021 and 01/2022. The interval between complete blood count (CBC) and CT scan acquisition had to be no more than seven days.
Purpose: To investigate the usefulness of virtual monoenergetic image (VMI) reconstructions derived from scans on a novel photon-counting detector CT (PCD-CT) for artifact reduction in patients after posterior spinal fixation.
Methods: This retrospective cohort study included 23 patients status post posterior spinal fixation. Subjects were scanned on a novel PCD-CT (NAEOTOM Alpha, Siemens Healthineers, Erlangen, Germany) as part of routine clinical care.