Influence of device-assisted suction against resistance (Mueller maneuver) on image quality in CTPA for suspected lung embolism.

OBJECTIVES: To investigate the effect of a device-assisted suction against resistance Mueller maneuver (MM) on transient interruption of contrast (TIC) in the aorta and pulmonary trunk (PT) on computed tomography pulmonary angiogram (CTPA). METHODS: In this prospective single-center study, 150 patients with suspected pulmonary artery embolism were assigned randomly with two different breathing maneuvers (Mueller maneuver (MM) or standard end-inspiratory breath-hold command (SBC)) during routine CTPA. The MM was performed using a patented prototype (Contrast Booster™) which allows both the patient by means of visual feedback and the medical staff in the CT scanning room to monitor whether the patient is sucking sufficiently or not. Mean Hounsfield attenuation in descending aorta and PT was measured and compared. RESULTS: Overall, patients with MM showed an attenuation of 338.24 HU in the pulmonary trunk, compared to 313.71 HU in SBC (p = 0.157). In the aorta, the values for MM were lower compared to SBC (134.42 HU vs. 177.83 HU, p = 0.001). The TP-aortic ratio was significantly higher in the MM group at 3.86 compared to the SBC group at 2.26, p = 0.001. TIC phenomenon was absent in the MM group, whereas it was present in 9 patients (12.3%) in the SBC group (p = 0.005). Overall contrast was better on all levels for MM (p < 0.001). The presence of breathing artifacts was higher in the MM group (48.1% vs. 30.1%, p = 0.038), without clinical consequence. CONCLUSIONS: Performing the MM with the application of the prototype is an effective way of preventing the TIC phenomenon during i.v. contrast-enhanced CTPA scanning compared to the standard end-inspiratory breathing command. CLINICAL RELEVANCE: Compared to standard end-inspiratory breathing command, the device-assisted Mueller maneuver (MM) improves contrast enhancement and prevents the transient interruption of contrast (TIC) phenomenon in CTPA. Therefore, it may offer optimized diagnostic workup and timely treatment for patients with pulmonary embolism. KEY POINTS: • Transient interruption of contrast (TIC) may impair image quality in CTPA. • Mueller Maneuver using a device prototype could lower the rate of TIC. • Device application in clinical routine may increase diagnostic accuracy.

Sparse 3D contrast-enhanced whole-heart imaging for coronary artery evaluation.

BACKGROUND: We investigated the feasibility of evaluating coronary arteries with a contrast-enhanced (CE) self-navigated sparse isotropic 3D whole heart T1-weighted magnetic resonance imaging (MRI) study sequence. METHODS: A total of 22 consecutive patients underwent coronary angiography and/or cardiac computed tomography (CT) including cardiac MRI. The image quality was evaluated on a 3-point Likert scale. Inter-reader variability for image quality was analyzed with Cohen's kappa for the main coronary segments (left circumflex [LCX], left anterior descending [LAD], right coronary artery [RCA]) and the left main trunk (LMT). RESULTS: Inter-reader agreement for image quality of the coronary tree ranged from substantial to perfect, with a Cohen's kappa of 0.722 (RCAmid) to 1 (LCXprox). The LMT had the best image quality. Image quality of the proximal vessel segments differed significantly from the mid- and distal segments (RCAprox vs. RCAdist, p < 0.05). The LCX segments showed no significant difference in image quality along the vessel length (LCXprox vs. LCXdist, p = n.s.). The mean acquisition time for the study sequence was 553 s (±46 s). CONCLUSION: Coronary imaging with a sparse 3D whole-heart sequence is feasible in a reasonable amount of time producing good-quality imaging. Image quality was poorer in distal coronary segments and along the entire course of the LCX.

Serial Changes in Coronary Plaque Formation Using CT Angiography in Patients Undergoing PCSK9-Inhibitor Therapy With 1-year Follow-up.

PURPOSE: Previous studies have shown positive effects of intensive low-density lipoprotein (LDL)-lowering therapy on atheroma volume using invasive intravascular ultrasound. This study describes the changes in coronary plaque composition on coronary computed tomography angiography in patients treated with proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors. MATERIALS AND METHODS: In this prospective study, coronary plaques were analyzed using third-generation dual-source computed tomography before and after 1 year of PCSK9-inhibitor treatment. Plaque markers included total plaque volume (TPV), calcified plaque volume (CPV), noncalcified plaque volume (NCPV), lumen volume and vessel volume (VV), minimal luminal area (MLA), minimal lumen diameter (MLD), corrected coronary opacification, eccentricity, remodeling index, and functional plaque parameters. Primary endpoint was defined as change in TPV; the secondary endpoint was TPV or CPV regression or nominal change in plaque parameters. RESULTS: We analyzed 74 coronary plaques in 23 patients (60±9 y, 65% male). After 1 year of PCSK9-inhibitor treatment, LDL was reduced from 148 to 66 mg/dL ( P <0.0001). Significant changes were found for VV (196 to 215 mm 3 , P =0.0340), MLA (3.1 to 2.6 mm 2 , P =0.0413), and MLD (1.7 to 1.4 mm, P =0.0048). TPV, CPV, NCPV, lumen volume, and functional plaque parameters did not change significantly ( P >0.05). CONCLUSIONS: Coronary artery plaque analysis by coronary computed tomography angiography highlights that LDL lowering therapy affects plaque composition. The primary endpoint of TPV change was not reached; however, VV, MLA, and MLD changed significantly.

Anthropometric measurements of the pediatric hip using CT-based simulated anteroposterior radiographs of the pelvis.

Normal anatomical variants and pathological deformities of the pediatric hip can only be differentiated after a prior definition of normal ranges for anthropometric parameters with increasing age. Aim of the present study was to provide reliable reference values of the pediatric hip morphometry, using computed tomography (CT)-based rotation-corrected summation images of the pelvis that simulate the widely available plain radiograph-based measurements, but offer the higher precision of the CT technique. This retrospective study included 85 patients (170 hips) under 15 years of age (0-15). The measured anthropometric parameters included femur head extrusion index, lateral center-edge angle, acetabular inclination, Tönnis angle, and femoral neck-shaft angle. Mean values, range, SD, P values, intra-rater, and inter-rater reliability were calculated. All measurements correlated with age. None of the measurements correlated with gender or side. Rapid growth phases were noted in all measurements at the age of 12 (14 in males and 11 in females). The inter-rater and intra-rater reliability was high (range inter/intraclass correlation coefficient 0.926-0.998 Cronbach's alpha 0.986-0.998). The present work provides age- and gender-related normative values of the classically used hip measurements as well as growth phases describing pediatric hip morphology in a broad age range. A discrepancy was noted between the values measured in the current study and the classical X-ray-based reference values in the literature especially for the Tönnis angle and LCEA values. This suggests that the rotation and inclination correction in the CT-based techniques might have the advantage of compensating for a possible overestimation in the conventional X-ray-based methods.

The development of visuospatial abilities and their impact on laparoscopic skill acquisition: a clinical longitudinal study.

OBJECTIVES: To investigate how visuospatial abilities develop and influence intraoperative laparoscopic performance during surgical residency training programmes. BACKGROUND: Laparoscopic surgery is a challenging technique to acquire and master. Visuospatial ability is an important attribute but most prior research have predominantly explored the influence of visuospatial abilities in lab-based settings and/or among inexperienced surgeons. Little is known about the impact of visuospatial profiles on actual laparoscopic performance and its role in shaping competency. METHOD: A longitudinal observational cohort study using a pair-matched design over 27 months. At baseline, visuospatial profiles of 43 laparoscopic surgeons of all expertise levels and 19 control subjects were compared. The development of visuospatial abilities and their association with intraoperative performance of 18 residency surgeons were monitored during the course of their laparoscopic training. RESULTS: Laparoscopic surgeons significantly outperformed the control group on the measure of spatial visualisation (U = 273.0, p = 0.03, η2 = 0.3). Spatial visualisation was found to be a significant predictor of laparoscopic expertise (R2 = 0.70, F (1.60) = 6.788, p = 0.01) and improved with laparoscopic training (B = 4.01, SE = 1.83, p = 0.02, 95% CI [0.40, 7.63]). From month 6 to 18, a strong positive correlation between spatial visualisation and intraoperative depth perception (r = 0.67, p < 0.01), bimanual dexterity (r = 0.60, p < 0.01), autonomy (r = 0.78, p < 0.01) and the total score (r = 0.70, p < 0.01) were observed but a strong relationship remained only with autonomy (r = 0.89, p < 0.01) and total score (r = 0.80, p < 0.01) at 18 months. CONCLUSION: In this longitudinal cohort study, visuospatial abilities associate with laparoscopic skills and improve with training. Spatial visualisation may be characteristic of laparoscopic expertise as it has clear association with competency development during laparoscopy residency training programme.

Anthropometric three-dimensional computed tomography reconstruction measurements of the acetabulum in children/adolescents.

The key element for differentiation between normal anatomical variants and pathological deformities is the prior definition of normal ranges for anthropometric parameters of acetabulum according to each age group. Aim of the present study is to analyze the development of the acetabulum in children/adolescents by accurate anthropometric measurements using 3D-CT scans and determine the variations occurring depending on age, gender and/or side. This retrospective observational study included 85 patients (170 hips) under 15 years of age (0-15) undergoing 1.5mm CT scanning for non-hip related reasons. The measurements were performed by 2 board-certified orthopaedic surgeons. Each year of life represented an age group forming a total of 16 groups. Median number of patients per age group was 12 (range 4-16). The anthropometric parameters included acetabular volume, inclination, version, depth (coronal and axial), width (coronal and axial), Tönnis angle as well as anterior and posterior acetabular sector angles. Mean values, range, standard deviation, p-values, intra- and interrater reliability were calculated. All measurement values correlated significantly with age. Statistically, there was no side or gender related difference. Rapid growth phases were observed at the age of 11-12. The inter- and intrarater reliability was high (range ICC 0.8-0.99, Cronbach alpha 0.86-0.99, Bland-Altman good agreement). The present data provides age- and gender-related normative values as well as growth phases describing acetabular morphology. It should help paediatricians as well as paediatric and orthopaedic surgeons as a tool for early diagnosis of deformity and guidance for possible procedures.

Preparing for future waves and pandemics: a global hospital survey on infection control measures and infection rates in COVID-19.

A survey of hospitals on three continents was performed to assess their infection control preparedness and measures, and their infection rate in hospital health care workers during the COVID-19 pandemic. All surveyed hospitals used similar PPE but differences in preparedness, PPE shortages, and infection rates were reported.

Detectability of Lung Nodules in Ultra-low Dose CT.

BACKGROUND/AIM: Investigation of the influence of different ultra-low dose computed tomography (ULDCT) protocols on the detection of solid and subsolid nodules in a phantom study. PATIENTS AND METHODS: A chest phantom with pulmonary nodules was scanned with different CT protocols ranging from ultra-low dose settings with spectral shaping to a standard low dose lung cancer screening protocol. Image analysis was performed with different reconstruction algorithms and dedicated computer aided detection (CAD), which was compared to manual readout. RESULTS: The highest sensitivity rates (83%) were achieved for the 90 mAs and 120 mAs protocols when reconstructed with ADMIRE 3 or 5 and manual readout. The only statistically significant difference was found for subsolid nodules with preference of manual readout compared to CAD (p<0.05). Dose levels for the mAs settings ranged from 0.029 to 0.2 mSv. CONCLUSION: Reliable detectability rates for solid nodules were achieved; CAD software did not prove reliable for subsolid nodules.

Anthropometry of the proximal femur and femoral head in children/adolescents using three-dimensional computed tomography-based measurements.

PURPOSE: Defining normal anthropometric ranges of proximal femur and femoral head for each age group in children/adolescents is a necessity when differentiating normal anatomical variants from pathological deformities. Aim of this study is to define a set of normal anthropometric parameters based on 3D-CT measurements in normal asymptomatic children/adolescents and analyse the variations arising depending on age, side, and/or gender. METHODS: Morphology of the proximal femur was retrospectively assessed in 170 hips (85 children, < 15 years). Measurements included covered femoral head volume (CFHV), femoral head diameter (FHD), femoral head extrusion index (FHEI), coronal alpha angle (CAA), lateral centre-edge angle (LCEA), anterior (AOS) and posterior head-neck offset (POS) and femoral neck-shaft angle (FNSA). Correlation analyses as well as inter- and intra-rater reliability were performed. RESULTS: CFHV, LCEA, FHD and AOS/POS increased with age and FHEI, CAA, and FNSA decreased with age. None of the measurements correlated with the side. AOS showed a poor correlation with gender. Rapid growth phases were observed at the age of 1, 7 and 11. The inter- and intra-rater reliability was high (range ICC 0.8-0.99 Cronbach alpha 0.86-0.99). CONCLUSION: This data delivers a description of growth phases as well as gender and age-correlated reference values of the proximal femoral morphology that could be used by paediatricians and orthopaedic/paediatric surgeons to early diagnose proximal femur deformities and provide guidance in the planning of possible operations.

Deterministic Arterial Input Function selection in DCE-MRI for automation of quantitative perfusion calculation of colorectal cancer.

Development of a deterministic algorithm for automated detection of the Arterial Input Function (AIF) in DCE-MRI of colorectal cancer. Using a filter pipeline to determine the AIF region of interest. Comparison to algorithms from literature with mean squared error and quantitative perfusion parameter Ktrans. The AIF found by our algorithm has a lower mean squared error (0.0022 ±â€¯0.0021) in reference to the manual annotation than comparable algorithms. The error of Ktrans (21.52 ±â€¯17.2%) is lower than that of other algorithms. Our algorithm generates reproducible results and thus supports a robust and comparable perfusion analysis.

Addressing intimate partner violence during the COVID-19 pandemic and beyond: how radiologists can make a difference.

Faced with the COVID-19 pandemic, many countries both in Europe and across the world implemented strict stay-at-home orders. These measures helped to slow the spread of the coronavirus but also led to increased mental and physical health issues for the domestically confined population, including an increase in the occurrence of intimate partner violence (IPV) in many countries. IPV is defined as behavior that inflicts physical, psychological, or sexual harm within an intimate relationship. We believe that as radiologists, we can make a difference by being cognizant of this condition, raising an alert when appropriate and treating suspected victims with care and empathy. The aim of this Special Report is to raise awareness of IPV among radiologists and to suggest strategies by which to identify and support IPV victims. KEY POINTS: • The COVID-19 pandemic led to a marked increase in the number of intimate partner violence (IPV) cases, potentially leading to increased emergency department visits and radiological examinations. • Most IPV-related fractures affect the face, fingers, and upper trunk, and may easily be misinterpreted as routine trauma. • Radiologists should carefully review the medical history of suspicious cases, discuss the suspicion with the referring physician, and proactively engage in a private conversation with the patient, pointing to actionable resources for IPV victims.

A quantitative CT parameter for the assessment of pulmonary oedema in patients with acute respiratory distress syndrome.

OBJECTIVES: The aim of this study was to establish quantitative CT (qCT) parameters for pathophysiological understanding and clinical use in patients with acute respiratory distress syndrome (ARDS). The most promising parameter is introduced. MATERIALS AND METHODS: 28 intubated patients with ARDS obtained a conventional CT scan in end-expiratory breathhold within the first 48 hours after admission to intensive care unit (ICU). Following manual segmentation, 137 volume- and lung weight-associated qCT parameters were correlated with 71 clinical parameters such as blood gases, applied ventilation pressures, pulse contour cardiac output measurements and established status and prognosis scores (SOFA, SAPS II). RESULTS: Of all examined qCT parameters, excess lung weight (ELW), i.e. the difference between a patient's current lung weight and the virtual lung weight of a healthy person at the same height, displayed the most significant results. ELW correlated significantly with the amount of inflated lung tissue [%] (p<0.0001; r = -0.66) and was closely associated with the amount of extravascular lung water (EVLW) (p<0.0001; r = 0.72). More substantially than the oxygenation index (PaO2/FiO2) or any other clinical parameter it correlated with the patients' mean SOFA- (p<0.0001, r = 0.69) and SAPS II-Score (p = 0.0005, r = 0.62). Patients who did not survive intensive care treatment displayed higher values of ELW in the initial CT scans. CONCLUSIONS: ELW could serve as a non-invasive method to quantify the amount of pulmonary oedema. It might serve as an early radiological marker of severity in patients with ARDS.

Fusion imaging to evaluate the radiographic anatomical relationship between primary tumors and local recurrences in retroperitoneal soft tissue sarcoma.

BACKGROUND: Local recurrence (LR) of retroperitoneal soft tissue sarcoma (RPS) is a common and life-threatening event. The evaluation of the exact anatomical patterns of local recurrence might help to improve local treatment in RPS. METHODS: Of our local database we extracted ten patients with LR of RPS with axial MRI and/or CT datasets of the primary tumor (PT) and the LR. Using the Osirix DICOM viewer Version v.3.9.4 64-bit (Pixmeo, Geneva, Switzerland) we performed a three-step fusion algorithm consisting of: a) 3-point co-registration of the axial datasets depicting the PT and the LR using three abdominal landmarks b) re-orientation of the datasets and c) image fusion. We evaluated the feasibility of this technique with regard to categorizing the localization of LR as within or distant from the PT. RESULTS: Fusion imaging was feasible in seven out of ten patients. In the other three patients anatomical shifting of organs after surgery led to a relevant mismatch of anatomical landmarks and impeded interpretation of the fused images. In five of seven patients with successful fusion imaging, local recurrences were located within the anatomical borders of the primary tumor, in two out of seven patients local recurrences were distant to the primary. CONCLUSIONS: Fusion imaging of primary tumors and local recurrences is feasible in most patients with RPS. Most local recurrences occurred within the anatomical localization of the primary tumor. For further investigations validation of the technique in larger patient cohorts is required.

Intimate partner violence crisis in the COVID-19 pandemic: how can radiologists make a difference?

KEY POINTS: • The COVID-19 crisis resulted in a variety of physical and mental health issues beyond the viral infection itself, as indicated by an increase in domestic violence.• Radiologists should be aware of typical intimate partner violence (IPV) injury patterns, actively ask potential IPV victims about the cause of injury, and be familiar with support systems for IPV victims of their institutions.• Emergency and radiology departments should review their protocols for identifying and supporting IPV victims, and train their staff to work together to implement these measures during and beyond the COVID-19 crisis.

Comparison of Machine Learning Computed Tomography-Based Fractional Flow Reserve and Coronary CT Angiography-Derived Plaque Characteristics with Invasive Resting Full-Cycle Ratio.

BACKGROUND: The aim is to compare the machine learning-based coronary-computed tomography fractional flow reserve (CT-FFRML) and coronary-computed tomographic morphological plaque characteristics with the resting full-cycle ratio (RFRTM) as a novel invasive resting pressure-wire index for detecting hemodynamically significant coronary artery stenosis. METHODS: In our single center study, patients with coronary artery disease (CAD) who had a clinically indicated coronary computed tomography angiography (cCTA) and subsequent invasive coronary angiography (ICA) with pressure wire-measurement were included. On-site prototype CT-FFRML software and on-site CT-plaque software were used to calculate the hemodynamic relevance of coronary stenosis. RESULTS: We enrolled 33 patients (70% male, mean age 68 ± 12 years). On a per-lesion basis, the area under the receiver operating characteristic curve (AUC) of CT-FFRML (0.90) was higher than the AUCs of the morphological plaque characteristics length/minimal luminal diameter4 (LL/MLD4; 0.80), minimal luminal diameter (MLD; 0.77), remodeling index (RI; 0.76), degree of luminal diameter stenosis (0.75), and minimal luminal area (MLA; 0.75). CONCLUSION: CT-FFRML and morphological plaque characteristics show a significant correlation to detected hemodynamically significant coronary stenosis. Whole CT-FFRML had the best discriminatory power, using RFRTM as the reference standard.

Additional Value of Machine-Learning Computed Tomographic Angiography-Based Fractional Flow Reserve Compared to Standard Computed Tomographic Angiography.

Background: Machine-learning-based computed-tomography-derived fractional flow reserve (CT-FFRML) obtains a hemodynamic index in coronary arteries. We examined whether it could reduce the number of invasive coronary angiographies (ICA) showing no obstructive lesions. We further compared CT-FFRML-derived measurements to clinical and CT-derived scores. Methods: We retrospectively selected 88 patients (63 ± 11years, 74% male) with chronic coronary syndrome (CCS) who underwent clinically indicated coronary computed tomography angiography (cCTA) and ICA. cCTA image data were processed with an on-site prototype CT-FFRML software. Results: CT-FFRML revealed an index of >0.80 in coronary vessels of 48 (55%) patients. This finding was corroborated in 45 (94%) patients by ICA, yet three (6%) received revascularization. In patients with an index ≤ 0.80, three (8%) of 40 were identified as false positive. A total of 48 (55%) patients could have been retained from ICA. CT-FFRML (AUC = 0.96, p ≤ 0.0001) demonstrated a higher diagnostic accuracy compared to the pretest probability or CT-derived scores and showed an excellent sensitivity (93%), specificity (94%), positive predictive value (PPV; 93%) and negative predictive value (NPV; 94%). Conclusion: CT-FFRML could be beneficial for clinical practice, as it may identify patients with CAD without hemodynamical significant stenosis, and may thus reduce the rate of ICA without necessity for coronary intervention.

Blunt force trauma: an exceptional example of an ancient Egyptian mummy head.

In the course of a scientific cooperation between the German Mummy Project at the Reiss-Engelhorn-Museen, Mannheim (Germany) and the Musée National d'Histoire et d'Art Luxembourg (Luxembourg), an ancient Egyptian mummy head was analyzed using a multidisciplinary approach including radiocarbon dating, ultra-high resolution computed tomography, physical anthropology, forensic medicine and Egyptology. Dated to the Roman Period, the mummy head belonged to an upper-class woman between 25 and 35 years of age. Computed tomography revealed a lethal blunt force trauma affecting the dorsal parts of the parietal bones, below the intact overlaying soft tissue. Moreover, ancient medical treatment was evidenced through localized shaving of the hair on the affected area, which indicates that efforts have been made to keep the woman alive. This astonishing example of homicide demonstrates the enormous scientific benefit brought by the multidisciplinary investigation of mummified bodies and body parts, and sheds light on life, death and medical care of a woman from Roman Period Egypt.