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Objectives To define and compare growth rates of the distal aorta in Marfan patients with and without aortic root replacement using serial MR angiography (MRA). Methods We retrospectively included 136 Marfan patients with a total of 645 MRAs who underwent a median of five MRAs (range: 2–13) at 1.5 T and 3 T in annual intervals. Of these, 41 patients (34.8 ± 12 years) had undergone aortic root replacement. The remaining 95 patients (29.0 ± 17 years) still had a native aorta and served as the control group. Thoracic aortic diameters were independently measured at eleven predefined levels. Estimated growth rates were calculated using a mixed effects model adjusted for sex, age, BMI, and medication. Results Marfan patients with aortic root replacement revealed the highest mean estimated growth rate in the proximal descending aorta (0.77 mm/year, CI: 0.31–1.21). Mean growth rates at all levels of the distal thoracic aorta were significantly higher in patients with aortic root replacement (0.28–0.77 mm/year) when compared to patients without aortic root replacement (0.03–0.07 mm/year) (all p Conclusion Distal thoracic aortic diameters increase at a significantly higher rate in Marfan patients with aortic root replacement compared to Marfan patients without aortic root replacement. Further studies are warranted to investigate if the increased growth rate of the distal thoracic aorta after aortic root replacement is caused by altered hemodynamics due to the rigid aortic root graft or due to the general genetic disposition of post-operative Marfan patients. Clinical relevance statement High growth rates of the distal aorta after aortic root replacement underline the need for careful life-long aortic imaging of Marfan patients after aortic root replacement. Key Points • Aortic growth rates in Marfan patients with aortic root replacement are highest in the mid-aortic arch, the proximal- and mid-descending aorta. • Growth rates of the distal thoracic aorta are significantly higher in Marfan patients with aortic root replacement compared to Marfan patients without aortic root replacement. • Antihypertensive medication, gender, and BMI have no significant impact on distal aortic growth rates in Marfan patients.

To evaluate the sensitivity, specificity, and interobserver reliability of high-pitch dual-source computed tomography angiography (CTA) in the detection of anomalous pulmonary venous connection (APVC) in infants with congenital heart defects and to assess the associated radiation exposure. 78 pulmonary veins in 17 consecutively enrolled patients with congenital heart defects (6 females; 11 males; median age: 6 days; range: 1-299 days) were retrospectively included in this study. All patients underwent high-pitch dual-source CTA of the chest at low tube voltages (70 kV). APVC was evaluated independently by two radiologists. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV), and interobserver agreement were determined. For standard of reference, one additional observer reviewed CT scans, echocardiography reports, clinical reports as well as surgical reports. In cases of disagreement the additional observer made the final decision based on all available information. Detection of APVC with high-pitch dual-source CTA revealed a good sensitivity (91 %) and specificity (99 %), with PPV and NPV of 98 % and 97 %. Interobserver agreement was almost perfect (Kappa = 0.84). The median DLP was 3.8 mGy*cm (IQR 3.3-4.7 mGy*cm) and the median radiation dose was 0.33 mSv (IQR 0.26-0.39 mSv). High-pitch dual-source CTA in infants with congenital heart defects allows for accurate and reliable assessment of APVC at a low radiation dose. · High-pitch dual-source CTA enables detection of anomalous pulmonary vein connection with high sensitivity in infants.. · Interrater reliability in the detection of anomalous pulmonary vein connection with high-pitch dual-source CTA is almost perfect.. · Radiation dose of high-pitch dual-source CTA in the cardiac examination of infants is low..· Well L, Weinrich JM, Meyer M et al. Sensitivity of High-Pitch Dual-Source Computed Tomography for the Detection of Anomalous Pulmonary Venous Connection in Infants. Fortschr Röntgenstr 2021; 193: 551 - 558.ZIEL: Bewertung der Sensitivität, Spezifität und Interrater-Reliabilität der High-Pitch-Dual-Source-Computertomografie-Angiografie (CTA) in der Detektion von Pulmonalvenenfehlmündungen bei Säuglingen mit angeborenen Herzfehlern und Bewertung der damit verbundenen Strahlenbelastung. In diese retrospektive Studie wurden 78 Lungenvenen aus 17 konsekutiv untersuchten Säuglingen mit angeborenen Herzfehlern eingeschlossen (6 Mädchen, 11 Jungen; Medianalter 6 Tage, Range 1–299 Tage). Bei allen Patienten wurde eine High-Pitch-Dual-Source-CTA des Thorax bei niedriger Röhrenspannung (70 kV) durchgeführt. Das Vorliegen von Pulmonalvenenfehlmündungen wurde von 2 Radiologen unabhängig voneinander bewertet. Sensitivität, Spezifität, positive (PPV) und negative prädiktive Vorhersagewerte (NPV) sowie die Interrater-Reliabilität wurden bestimmt. Als Referenzstandard diente die Kombination aus CT-Scans, Befunden der Echokardiografie, klinischen Berichten sowie Operationsberichten, die von einem erfahrenen Kinderradiologen in Zusammenschau ausgewertet wurden. Dieser entschied im Fall inkongruenter Befunde über die korrekte Interpretation. Die Detektion von Pulmonalvenenfehlmündungen mit der High-Pitch-Dual-Source-CTA gelang mit guter Sensitivität (91 %) und Spezifität (99 %), bei PPV und NPV von 98 % und 97 %. Die Interrater-Reliabilität war nahezu perfekt (Kappa = 0,84). Der Median des DLP betrug 3,8 mGy*cm (IQR 3,3–4,7 mGy*cm), die effektive Dosis betrug im Median 0,33 mSv (IQR 0,26–0,39 mSv). Die High-Pitch-Dual-Source-CTA bei Säuglingen mit angeborenen Herzfehlern ermöglicht eine genaue und zuverlässige Detektion von Lungenvenenfehlmündungen bei niedriger Strahlendosis. · Die High-Pitch-Dual-Source-CTA ermöglicht die Detektion von Pulmonalvenenfehlmündungen bei Säuglingen mit hoher Sensitivität.. · Die Interrater-Reliabilität bei der Erkennung von Pulmonalvenenfehlmündungen mit High-Pitch-Dual-Source-CTA ist hoch.. · Die Strahlendosis der High-Pitch-Dual-Source-CTA bei der kardialen Untersuchung von Säuglingen ist gering..

Aortic diameter measurements play a crucial role for the indication of aortic root surgery in Marfan patients. However, for magnetic resonance angiography (MRA)-derived measurements, there is no consensus on whether the aortic wall should be included or excluded in the aortic diameter. The purpose of this retrospective study was to compare the reliability of non-contrast bright blood MRA aortic inner-to-inner and outer-to-outer edge measurements in patients with Marfan syndrome. Forty Marfan patients underwent ECG-gated balanced steady-state free-precession MRA of the aorta at 1.5 T. Two readers independently performed inner and outer measurements at different aortic levels. They rated the image quality of the delineation of both inner and outer vessel wall edges on a four-point scale. MRA-derived diameters of the sinuses of Valsalva were compared with echocardiography-derived diameters. Aortic vessel wall delineation score was rated higher at all levels for inner than for outer vessel walls (p

Background Aortic valve repair has become a treatment option for adults with symptomatic bicuspid (BAV) or unicuspid (UAV) aortic valve insufficiency. Our aim was to demonstrate the feasibility of 4D flow cardiovascular magnetic resonance (CMR) to assess the impact of aortic valve repair on changes in blood flow dynamics in patients with symptomatic BAV or UAV. Methods Twenty patients with adult congenital heart disease (median 35 years, range 18–64; 16 male) and symptomatic aortic valve regurgitation (15 BAV, 5 UAV) were prospectively studied. All patients underwent 4D flow CMR before and after aortic valve repair. Aortic valve regurgitant fraction and systolic peak velocity were estimated. The degree of helical and vortical flow was evaluated according to a 3-point scale. Relative flow displacement and wall shear stress (WSS) were quantified at predefined levels in the thoracic aorta. Results All patients underwent successful aortic valve repair with a significant reduction of aortic valve regurgitation (16.7 ± 9.8% to 6.4 ± 4.4%, p p = 0.014). Both helical flow (1.6 ± 0.6 vs. 0.9 ± 0.5, p p = 0.002) as well as both flow displacement (0.3 ± 0.1 vs. 0.25 ± 0.1, p = 0.031) and WSS (0.8 ± 0.2 N/m2 vs. 0.5 ± 0.2 N/m2, p Conclusions 4D flow CMR allows assessment of the impact of aortic valve repair on changes in blood flow dynamics in patients with bicuspid aortic valve disease.

OBJECTIVE. The purpose of this study is to investigate the feasibility of submillisievert CT of the skeletal pelvis of human cadavers using a standard-dose protocol and four different reduced-dose ...

Patients with genetic aortic syndromes such as Marfan or Loeys-Dietz syndrome have a decreased life expectancy due to the risk of aortic dissection and rupture. Imaging plays an important role in the acute setting but also in the initial diagnosis and image-based monitoring. In this article, we provide an overview of the most common genetic aortic syndromes and recommended imaging strategies. Furthermore, we highlight modern imaging methods allowing for the quantification of hemodynamic changes in aortic disease. This is a narrative review article on genetic aortic syndromes and recommended imaging strategies, where we take into account expert opinions and standard-of-care practices from our own center. Radiological imaging plays a key role in the initial diagnosis and surveillance of patients with genetic aortic syndromes. Radiologists contribute significantly to the multi-disciplinary setting of genetic aortic syndromes with knowledge of special features and recommended imaging methods. Accurate measurement of the aorta is crucial, particularly in terms of diameter-based surgical treatment algorithms. Modern imaging methods like 4D-flow MRI and pulse wave velocity have a potential to further improve individualized risk stratification in patients with genetic aortic syndromes. · The risk for cardiovascular complications such as acute aortic syndrome is increased in patients with genetic aortic syndromes.. · Recommended time intervals between image-based monitoring depend on the underlying aortic disease.. · CT-angiography should be used only in the acute setting.. · Non-contrast MR-angiography is adequate for screening and image-based monitoring of patients with genetic aortic syndromes..· Weinrich JM, Lenz A, Girdauskas E et al. Current and Emerging Imaging Techniques in Patients with Genetic Aortic Syndromes. Fortschr Röntgenstr 2020; 192: 50 - 58. Genetische Aortenerkrankungen wie das Marfan- oder Loeys-Dietz-Syndrom umfassen ein relativ kleines, jedoch wichtiges kardiovaskuläres Patientenkollektiv. Die betroffenen Patienten unterscheiden sich durch diverse Phänotypen, haben jedoch alle bereits in jungem Alter ein sehr hohes Risiko für ein akutes Aortensyndrom. Sowohl in der Akutsituation als auch im Rahmen der Vorsorge ist die Schnittbildgebung unverzichtbar. In diesem Übersichtsartikel stellen wir die häufigsten genetischen Aortenerkrankungen und die für sie empfohlene Bildgebung vor. Darüber hinaus geben wir einen Ausblick auf moderne Methoden zur Erfassung der Hämodynamik bei Aortenerkrankungen. Diese Übersichtsarbeit basiert auf der Kombination publizierter Expertenmeinungen sowie den klinischen Standards unseres auf Aortenerkrankungen spezialisierten Zentrums. Die radiologische Bildgebung ist zentraler Bestandteil der initialen Diagnosestellung und Verlaufskontrolle genetischer Aortenerkrankungen und unterscheidet sich in Abhängigkeit der Grunderkrankung. Durch Kenntnis der Besonderheiten genetischer Aortenerkrankungen und der empfohlenen Bildgebungstechniken trägt der Radiologe wesentlich zur optimalen Patientenbetreuung bei. Die genaue Vermessung der Aortendiameter beeinflusst maßgeblich den interdisziplinären Beschluss eines prophylaktischen chirurgischen Aortenersatzes. Moderne Bildgebungstechniken wie die 4D-Fluss-MRT und die Pulswellengeschwindigkeit haben das Potenzial, die individualisierte Risikostratifizierung bei Patienten mit genetischen Aortenerkrankungen zu verbessern. · Patienten mit genetischen Aortenerkrankungen haben bereits in jungem Alter ein erhöhtes Risiko für vaskuläre Komplikationen wie das akute Aortensyndrom.. · Die Schnittbildgebung ist sowohl in der Akutsituation als auch im Rahmen der Vorsorge unverzichtbar.. · Die empfohlenen Zeitabstände und die Zielorgane für bildgebende Verlaufsuntersuchungen unterscheiden sich in Abhängigkeit von der Aggressivität der genetischen Aortenerkrankung.. · Die CT-Angiografie sollte nur in der Akutsituation oder in der präoperativen bzw. präinterventionellen Therapieplanung eingesetzt werden.. · Im Rahmen der Vorsorge empfiehlt sich die native MR-Angiografie der Aorta..· Weinrich JM, Lenz A, Girdauskas E et al. Current and Emerging Imaging Techniques in Patients with Genetic Aortic Syndromes. Fortschr Röntgenstr 2020; 192: 50 – 58.

We present a patient with severe tracheal stenosis resulting from a compression by the innominate artery 6 months after an arterial switch operation in a dextro-transposition of the great arteries. Segmentation and three-dimensional (3D) visualization were derived from a contrast-enhanced dual-source computed tomography and post-processing was performed using a dedicated open-source platform (3D Slicer). Post-processing allowed a comprehensible visualization of the relationship of the innominate artery to the trachea when compared to standard computer tomography reformations. Finally, the surgical approach to move the innominate artery anteriorly in order to relieve the tracheal obstruction was emphasized based on the improved 3D visualization of the actual pathology. An effective aortopexy could be performed and the postoperative result was confirmed by a second 3D visualization. About 3 months of follow-up, the patient is completely asymptomatic. Three-dimensional visualization offers excellent opportunities for diagnosis, treatment planning and follow-up in patients with a vascular-related tracheal stenosis in the context of congenital heart disease.

We evaluated the accuracy of preoperative CT in staging colonic diverticulitis (ACD) by using the classification of diverticular disease (CDD) and investigated the diagnostic impact of water enema (WE) and visceral obesity.In this retrospective study, the radiological and hospital information system was searched for patients who underwent CT for clinically suspected ACD prior to surgery between 2009 and 2019. From the initial population (n = 164), we included 155 patients (94.5 %) (85 women; mean age: 58 ± 13 years) matching the following inclusion criteria: i.) clinically suspected ACD, ii.) i.v. contrast-enhanced CT, iii.) surgery for ACD within 1 week after CT, iv.) histopathological report that proved ACD. The remaining 9 patients (5.5 %) were excluded because histopathological reports were lacking (n = 3) or CT was performed without intravenous contrast agent (n = 6). WE (+ butylscopolamine i.v.) was performed in 93 patients (group A, 60 %). 62 patients (group B, 40 %) had no WE. Visceral-to-subcutaneous fat ratio (V/S) was determined for each patient. Two radiologists blinded for final diagnosis independently staged ACD according to CDD and assessed prevalence and confidence ratings of ACD-related CT-findings: pericolonic fat stranding, covered- and free-perforation, local and generalized peritonitis, abscess. Interobserver-agreement of CT-findings were assessed and effects of WE and V/S ratio on the diagnostic accuracy of CT with surgical and histopathological findings as reference were determined by calculating a logistic regression model.CT-staging showed high accuracy (94 %) and excellent interrater-correlation (ICC 0.96) for staging ACD. WE had no positive impact neither on diagnostic accuracy of staging, nor on confidence ratings of ACD-related CT-findings (all p 0.5). Confidence ratings were significantly higher in examinations without WE for perforation, peritonitis as well as abscesses (all p 0.5). Confidence ratings for the assessment of local peritonitis improved significantly with higher V/S (p = 0.049). The increase of V/S significantly correlated with the probability for correct CDD staging of ACD in CT (p = 0.023).Increase of visceral obesity significantly improves accuracy of CT in preoperative staging acute colonic diverticulitis. However, independently of the degree of visceral obesity, water enema has no diagnostic benefit and may therefore be omitted. Overall, CT proves high accuracy in preoperative staging ACD using the classification of diverticular disease.Retrospective study, observational study.

Reproducible aortic diameter measurements are crucial for assessment of aortic growth and aneurysm formation in patients with Marfan syndrome. The objective of this study was to perform an intraindividual comparison of aortic measurements at 1.5 T and 3 T using non-contrast magnetic resonance angiography (MRA) in pre-surgical and post-surgical Marfan patients.Forty consecutive Marfan patients were retrospectively evaluated by ECG-gated 2D balanced steady-state free precession (bSSFP) MRA at 1.5 T and 3 T after 363 ± 58 days. 24 patients were before and 16 patients after aortic root surgery. Two readers independently measured aortic diameters at seven aortic levels and rated the image quality/image artifacts (1 = poor/severe, 4 = excellent/none). Contrast-to-noise ratio (CNR) and signal intensity slopes between aortic lumen and vessel walls were semiautomatically determined.In pre-surgical Marfan patients, interobserver agreement of aortic root diameter measurements was significantly higher at 3 T compared to 1.5 T (p0.05). In post-surgical Marfan patients, image quality and artifacts were significantly worse at 3 T compared to 1.5 T (p0.05). CNR was higher at 3 T compared to 1.5 T at all aortic levels. Significantly steeper slopes of signal intensity curves were observed at 3 T at all aortic levels (p0.001).In pre-surgical Marfan patients, non-contrast MRA provides higher reproducibility of aortic diameter measurements at 3 T compared to 1.5 T. In post-surgical Marfan patients, metallic implants result in significantly worse imaging artifacts and reduced image quality at 3 T compared to 1.5 T. Therefore, we propose to monitor the thoracic aorta with non-contrast MRA at 3 T in pre-surgical Marfan patients and at 1.5 T in post-surgical Marfan patients.

PurposeFeasibility of a highly reduced-dose lumbar spine CT protocol using iterative reconstruction (IR) in a human cadaver model.Materials and methodsThe lumbar spine of 20 human cadavers was repeatedly examined using three different reduced-dose protocols (RDCT) with decreasing reference tube current-exposure time products (RDCT-1: 50 mAs; RDCT-2: 30 mAs; RDCT-3: 10 mAs) at a constant tube voltage of 140 kV. A clinical standard-dose protocol (SDCT) served as the reference (reference tube current-exposure time product: 70 mAs; tube voltage: 140 kV). Images were reconstructed using filtered back projection (FBP) and two increasing levels of IR: IRL4 and IRL6. A five-point scale was used by two observers to assess the diagnostic quality of anatomical structures (cortical and trabecular bone, intervertebral foramina, pedicles and intervertebral joints, spinous and transverse processes). Objective image noise (OIN) was measured. Results were interpreted using a linear mixed-effects regression model.ResultsRDCT-2 with IRL6 (1.2 ± 0.5mSv) was the lowest reduced-dose protocol which provided diagnostically acceptable and equivalent image quality compared to the SDCT (2.3 ± 1.1mSV) with FBP (p > 0.05). All RDCT protocols achieved a significant reduction of the mean (±SD) effective radiation doses (RDCT-1: 1.7±0.9mSv; RDCT-2: 1.2±0.5mSv; RDCT-3: 0.4±0.2mSv; p < 0.05) compared to SDCT. OIN was lower in all RDCT protocols with the application of IRL4 and IRL6, compared to the SDCT with FBP (p < 0.05).ConclusionHighly reduced-dose lumbar spine CT providing diagnostically acceptable image quality is feasible using IR in this cadaver model and may be transferred into a clinical setting.

Vasculitides are a complex group of diseases sharing the defining feature of inflamed vessel walls. Vasculitides can be classified depending on the size of the predominantly affected vessels. Modern cross-sectional imaging methods have become a cornerstone in the diagnosis of vasculitis and may help in narrowing down differential diagnoses. This review presents the most important imaging modalities and typical findings in large and medium size vasculitis, implementing current imaging recommendations.

OBJECTIVE. The purpose of this study was to determine the prevalence and demographic distribution of colonic diverticulitis (CD) and alternative diagnoses (AD), as well as the diagnostic accuracy of MDCT in patients with suspected CD. MATERIALS AND METHODS. This study retrospectively included 1069 patients (560 women) undergoing MDCT for the evaluation of suspected CD. The prevalence of CD and AD was determined and the diagnostic accuracy of MDCT calculated. The final clinical diagnosis derived from the discharge report served as the standard of reference. Prevalence of diagnoses by age, sex, and admission status were compared using Cochran-Armitage, chi-square, and Fisher exact tests. RESULTS. Prevalence of CD was 52.5% (561/1069) and of AD was 39.9% (427/1069). In the remaining 7.6% (81/1069) no final clinical diagnosis was established. The most frequent AD were appendicitis (12.6%, 54/427), infectious colitis (10.5%, 45/427), infectious gastroenteritis (8.2%, 35/427), urolithiasis (6.1%, 26/427), and pyelonephritis (4.9%, 21/427). The prevalence of diverticulitis and AD varied statistically significantly according to both age (p < 0.001) and admission status (p < 0.001). Also, the prevalence of the 10 most frequent specific AD varied statistically significantly according to sex (p = 0.022). CT had a sensitivity and specificity of 99.1% and 99.8% for diagnosing CD and 92.7% and 98.8% for AD, respectively. CONCLUSION. In about 40% of patients with suspected diverticulitis a broad spectrum of AD is causative for symptoms. MDCT provides high diagnostic accuracy in the diagnosis of diverticulitis and AD. The prevalence of diagnoses is related to admission status and demographic data; in particular age-related AD have to be considered in patients with clinically suspected diverticulitis.

Objectives This study analyzed the presence of myocardial fibrosis detected by late gadolinium-enhancement (LGE) cardiac magnetic resonance (CMR) in correlation with the performance of competitive triathletes objectified by an exercise test and individual competition history. Background Myocardial fibrosis detected by LGE CMR has been reported to occur in 0% to 50% of asymptomatic athletes. However, the cause and mechanisms of myocardial fibrosis are unclear. Methods Eighty-three asymptomatic triathletes undergoing >10 training h per week (43 ± 10 years of age; 65% male) and 36 sedentary controls were studied by using LGE and extracellular volume (ECV) CMR. Parameters of physical fitness were measured by spiroergometry. Triathletes reported their lifetime competition results. Results LGE CMR revealed focal nonischemic myocardial fibrosis in 9 of 54 (17%) male triathletes (LGE + ) but in none of the female triathletes (p + triathletes had higher peak exercise systolic blood pressure (213 ± 24 mm Hg) than LGE − triathletes (194 ± 26 mm Hg; p + triathletes (93 ± 7 g/m 2 ) than in LGE − triathletes (84 ± 11 g/m 2 ; p 0.05). ECV in LGE − myocardium was higher in LGE + triathletes (26.3 ± 1.8%) than in LGE − triathletes (24.4 ± 2.2%; p + triathletes completed longer cumulative distances in swimming and cycling races and participated more often in middle and Iron Man distances than LGE − triathletes. A cycling race distance of >1,880 km completed during competition had the highest accuracy to predict LGE, with an area under the curve value of 0.876 (p Conclusions Myocardial fibrosis in asymptomatic triathletes seems to be associated with exercise-induced hypertension and the race distances. There appears to be a safe upper limit, beyond which exercise may result in myocardial fibrosis.

Background To determine the type and frequency of vascular and organ malformations in adults with thalidomide embryopathy (TE) using non-contrast magnetic resonance angiography (MRA) and to assess the effect of the observed malformations on renal function. Methods and Results: The institutional ethics committee approved this prospective study and written informed consent was given by all 78 subjects (50 females) with TE (mean age: 55±1.1 years), who were examined by non-contrast MRA at 3T. ECG-triggered balanced turbo field echo images of the chest, abdomen and pelvis were obtained in coronal and sagittal orientations. Two observers assessed the frequency of vascular and organ malformations. Serum creatinine and estimated glomerular filtration rate (eGFR) were obtained to assess renal function. In 58 subjects, 99 vascular anomalies were observed, including 68 arterial (69%) and 31 venous anomalies (31%); 15 patients had 16 abdominal organ malformations including 12 kidney anomalies and 4 cases of gallbladder agenesis. Most vascular anomalies affected the renal vessels (n=66, 67%) or supraaortic arteries (n=28, 28%). Serum creatinine and eGFR revealed normal renal function in all subjects. Conclusions Vascular and organ anomalies occurred in a high number of subjects with TE without evidence of renal dysfunction. Information about the presence of malformations may be important for future surgical interventions in subjects with TE.

The purpose of this study is to assess the diagnostic yield of low-dose (LD) CT for alternative diagnoses in patients with suspected urolithiasis.In this retrospective study, we included 776 consecutive patients who underwent unenhanced abdominal CT for evaluation of suspected urolithiasis. All examinations were performed with an LD CT protocol; images were reconstructed using iterative reconstruction. The leading LD CT diagnosis was recorded for each patient and compared with the final clinical diagnosis, which served as the reference standard.The mean (± SD) effective dose of CT was 1.9 ± 0.6 mSv. The frequency of urolithiasis was 82.5% (640/776). LD CT reached a sensitivity of 94.1% (602/640), a specificity of 100.0% (136/136), and an accuracy of 95.1% (738/776) for the detection of urolithiasis. In 93 of 136 patients (68.4%) without urolithiasis, alternative diagnoses were established as the final clinical diagnoses. Alternative diagnoses were most commonly located in the genitourinary (n = 53) and gastrointestinal (n = 18) tracts. LD CT correctly provided alternative diagnoses for 57 patients (61.3%) and was false-negative for five patients (5.4%). The most common clinical alternative diagnoses were urinary tract infections (n = 22). Seven diagnoses missed at LD CT were located outside the FOV. For 43 of all 776 patients (5.5%), neither LD CT nor clinical workup could establish a final diagnosis. The sensitivity, specificity, and accuracy of LD CT for the detection of alternative diagnoses were 91.9% (57/62), 95.6% (43/45), and 93.5% (100/107), respectively.LD CT enables the diagnosis of most alternative diagnoses in the setting of suspected urolithiasis. The most frequent alternative diagnoses missed by LD CT are urinary tract infections or diagnoses located outside the FOV of the abdominopelvic CT scan.

Gadoxetate disodium is an intracellular contrast agent for magnetic resonance imaging (MRI) of the liver. Recent publications revealed that injection of gadoxetate disodium can lead to imaging artifacts due to transient severe motion (TSM) in the arterial phase of contrast-enhanced liver MRI. In this review we present and discuss published frequencies of TSM, contrast injection and image acquisition protocols, potential risk factors, and proposed strategies to avoid or minimize the effects of TSM.Two reviewers independently searched the PubMed search engine for "transient severe motion artifact" and related terms. Reference lists of retrieved articles were also searched. The two reviewers selected in consensus nine studies that reported both frequencies of TSM and potential risk factors. Study data were extracted by both reviewers, and disagreement was resolved by consensus.TSM is caused by impaired breath-hold ability after gadoxetate disodium injection and occurs in 5 - 22 % of patients. The dose of applied contrast agent, repeated exposure to gadoxetate disodium, high BMI and pulmonary disease have been described as potential risk factors for TSM. However, there are only few concordant results on this topic and the pathophysiology of TSM has not been identified. Proposed strategies for the prevention of TSM are slow injection rates and low doses of diluted gadoxetate disodium. Accelerated and free-breathing MRI sequence protocols and breath-hold training may minimize the effects of TSM. Further prospective studies are needed to confirm these strategies and to identify the underlying mechanism of TSM.· TSM occurs in 5 - 22 % of patients after gadoxetate disodium injection.. · Potential risk factors of TSM are dose, repeated exposure, BMI, pulmonary disease.. · The underlying mechanism for TSM has not been identified.. · Slow injection rates and diluted gadoxetate disodium may prevent TSM.. · Accelerated image acquisition or free-breathing sequences may mitigate the effects of TSM..· Well L, Weinrich JM, Adam G et al. Transient Severe Respiratory Motion Artifacts After Application of Gadoxetate Disodium: What We Currently Know. Fortschr Röntgenstr 2018; 190: 20 - 30.Dinatriumgadoxetat ist ein intrazelluläres Kontrastmittel für die Leberbildgebung in der Magnetresonanztomografie (MRT). In aktuellen Publikationen wurde das Auftreten transienter schwerer Atemartefakte (TSA) nach Gabe von Dinatriumgadoxetat beschrieben, die zur Reduktion der Bildqualität in der arteriellen Konstrastmittelphase führen. In diesem Übersichtsartikel vergleichen wir den Einfluss publizierter Untersuchungsprotokolle und potentieller Risikofaktoren auf die Häufigkeit des Auftretens der TSA. Zudem diskutieren wir vorgeschlagene Strategien zur Vermeidung oder Minimierung der Effekte der TSA.Diese Übersichtsarbeit basiert auf einer Literaturrecherche der PubMed Datenbank, welche nach „transient severe motion artifact“ und verwandten Begriffen unabhängig voneinander von zwei Autoren durchsucht wurde. Die Literaturverzeichnisse der identifizierten Arbeiten wurden ebenfalls durchsucht. Zwei Autoren wählten gemeinsam neun Arbeiten aus, in denen sowohl die Frequenz der TSA als auch potentielle Risikofaktoren untersucht wurden. Relevante Studiendaten wurden von den Autoren extrahiert, Diskrepanzen der extrahierten Daten wurden im Konsens gelöst.Die TSA werden durch eine Beeinträchtigung der Atemanhaltefähigkeit nach Gabe von Dinatriumgadoxetat verursacht und treten in 5 – 22 % aller Dinatriumgadoxetat-verstärkten Leber-MRTs auf. Die Kontrastmitteldosis, wiederholte Dinatriumgadoxetat-Exposition, hoher Body Mass Index sowie pulmonale Erkrankungen werden als potentielle Risikofaktoren für das Auftreten der TSA beschrieben. Allerdings finden sich nur wenig übereinstimmende Resultate hinsichtlich der Risikofaktoren, und die ursächliche Pathophysiologie der TSA ist bis heute ungeklärt. Vorgeschlagene Strategien zur Vermeidung der TSA sind niedrige Injektionsraten und Gabe von verdünntem, niedrig dosiertem Dinatriumgadoxetat. Durch kürzere Sequenzen, Aufnahmen ohne Atemstillstand und Atemtraining der Patienten soll der Effekt der TSA minimiert werden. Zukünftige prospektive Studien müssen diese Strategien bestätigen und den zugrundeliegenden Mechanismus für das Auftreten der TSA ermitteln.· Die Dinatriumgadoxetat-verstärkte Leber-MRT führt in 5 – 22 % zu transienten schweren Atemartefakten.. · Potentielle Risikofaktoren für TSA sind Kontrastmitteldosis, wiederholte Dinatriumgadoxetat-Gabe, BMI sowie Lungenerkrankungen.. · Die Ursache für das Auftreten von TSA ist bislang ungeklärt.. · Niedrige Injektionsraten und verdünntes Dinatriumgadoxetat sollen das Auftreten von TSA vermeiden.. · Kürzere oder durchgeatmete MRT-Sequenzen sollen den Effekt der TSA minimieren..

Background According to the as low as reasonably achievable (ALARA) principle, radiation exposure in computed tomography (CT) should be minimized while maintaining adequate image quality. Dedicated CT protocols combined with iterative reconstruction (IR) can reduce radiation dose and/or improve image quality. Purpose To investigate the feasibility of extremely reduced-dose (RD) CT of the thoracic spine in human cadavers using a standard-dose (SD) and three different RDCT protocols reconstructed with filtered back projection (FBP) and IR. Material and Methods The thoracic spines of 11 cadavers were examined using different RDCT protocols with decreasing reference tube currents (RDCT-1: 50 mAs; RDCT-2: 30 mAs; RDCT-3: 10 mAs) at 140 kV. A clinical SDCT (70 mAs, 140 kV) served as reference. Raw data were reconstructed using FBP and two increasing levels of IR (IRL4 and IRL6). Images were evaluated for image quality, diagnostic acceptability, and visibility of anatomical structures according to a 5-point-scale. Results Regardless of the reconstruction technique, image quality was rated as diagnostically acceptable for all cadavers in SDCT and RDCT-1. Image quality of reconstructions with FBP were generally rated lower. Application of IR improved image quality ratings in SDCT and RDCT. RDCT-2 with IR was the most reduced-dose CT protocol which enabled diagnostically acceptable image quality in all cadavers. Compared to SDCT, RDCT protocols resulted in significantly reduced effective radiation doses (SDCT: 4.1 ± 1.5 mSv; RDCT-1: 2.9 ± 1.1 mSv; 2:1.7 ± 0.6 mSv; 3:0.6 ± 0.1 mSv; P = 0.001). Conclusion Diagnostically acceptable RDCT of the thoracic spine with 1.7 mSv is feasible using IR.

To assess the impact of iterative reconstruction and filtered back projection (FBP) on image quality in computed tomography (CT)-based forensic age estimation of the medial clavicular epiphysis. CT of the clavicle was performed in 19 patients due to forensic reasons (70 mAs/140 kVp). Raw data were reconstructed with FBP and with an iterative algorithm at level 4 and 6. Clavicular ossification stage was determined by two radiologists in consensus, firstly on FBP reconstructed images and secondly after reviewing all reconstructions including iDose 4 and 6. In addition, the 3 reconstructions were compared regarding artefacts and delineation of the meta-/epiphyseal interface. Quantitative image noise was measured. Quantitative noise was lower in iDose 6 reconstructed images than in FBP (P < 0.042), but not significantly lower between iDose 4 and FBP (P = 0.127). Side by side comparison revealed lesser qualitative image noise on both iDose reconstructed images than for FBP. The meta-/epiphyseal interface delineation was rated better on both iDose levels than with FBP. In 3 of 19 patients, the clavicular ossification stage was reclassified after iterative reconstructions had been additionally reviewed. Using iterative CT reconstruction algorithms, a reduction of image noise and an enhancement of image quality regarding the meta-/epiphyseal clavicular interface can be achieved. The study highlights the importance of image standardization as variation of reconstruction technique has impact on forensic age estimation.

Our aim was to determine the prevalence of tuberculosis (TB), the number needed to screen (NNS), and the diagnostic accuracy of chest X-ray (CXR) screening to detect active pulmonary TB during the 2015 European refugee crisis. We evaluated data of all refugees who underwent CXR screening in a single-centre of one German metropolitan area in 2015. We determined the prevalence of TB, NNS, and accuracy of CXR to detect active pulmonary TB. Reference method for active TB was the database of all definite TB cases registered at the Department of Public Health. A total of 17,487 immigrants underwent single-centre CXR screening in 2015; prevalence of definite pulmonary TB was 0.103%. The NNS for detecting one case of active pulmonary TB was 1749. CXR had a sensitivity of 55.6% [95% confidence interval (CI) 30.8–78.5%) and a specificity 98.3% (CI 98.1–98.5%) to reveal one case of active TB. Our single-centre study indicates that chest X-ray screening for TB during the 2015 European refugee crisis was of low yield due the low prevalence of TB and high number needed to screen, thus implicating the need for improved screening algorithms adapted to the overwhelming number of refugees. • Prevalence of pulmonary tuberculosis (TB) among refugees in 2015 was low (0.103%). • The number needed to screen to detect one case of active pulmonary TB was 1749. • Tuberculosis X-ray screening resulted in a low sensitivity and high specificity. • Tuberculosis X-ray screening during the European refugee crisis is of low yield. • Improved screening algorithms are needed due to the overwhelming the number of refugees.

Objective To quantify standard values of the discus interpubicus in healthy subjects and to determine reliability and repeatability using T2 relaxation time measurements at 3T. Methods 20 asymptomatic participants (10 male, 10 female; mean age: 27.3 years ±4.1, BMI: 22.2 ±1.8) underwent a 3T Magnetic Resonance Imaging (MRI) of the pelvic region in a supine position. We included sagittal and para-axial T2w sequences centred over the pubic symphysis in order to identify the complete discus interpubicus. For quantitative analysis, a multi-echo Turbo Spin Echo (TSE) sequence (including 12 echo times between 6.4 and 76.8 ms) was acquired and analysed by using an in-house developed quantification plugin tool (qMapIt) extending ImageJ. Two readers in consensus defined three central slices of the pubic symphysis with the greatest length. For each slice, both readers separately placed three regions-of-interest (ROI) covering the whole discus interpubicus. Both readers repeated the ROI placements in identical fashion after a four-week interval on the original MRI images. Statistical analysis included intraclass correlation coefficient (ICC), nonparametric Wilcoxon test, Fisher exact test and mean relaxation time in ms and 95% confidence intervals. Results T2 relaxation time analysis was performed for all 20 participants. In total, a mean relaxation time of all analysed segments for both observers was 48.6 (±6.3 ms), with a mean relaxation time for observer 1 of 48.7 (±6.0 ms) and for observer 2 of 48.5 ms (±6.6ms). The calculated ICC comparing inter- and intrarater reproducibility was excellent in all segments (≥0.75). Conclusion T2 mapping of the discus interpubicus demonstrates good inter- and intrarater repeatability as well as reliability. Mean relaxation times were calculated with 48.6ms in healthy volunteers.

Aim To evaluate the benefit of extracellular gadolinium-based contrast agent (GBCA) enhanced magnetic resonance imaging (MRI) in addition to conventional non-enhanced T2-weighted imaging (WI) for quantification of inflammatory or fibrotic alterations in the liver parenchyma of patients with primary sclerosing cholangitis (PSC). Material and methods MRI (3 T) examinations were reviewed retrospectively by two radiologists in 27 PSC patients (age 42.9±15.6 years), and 19 controls. Regions of interest (ROIs) were drawn onto T2 hyperintense and T2 isointense areas and copied to section position matched non-enhanced and delayed-phase contrast-enhanced T1WI. Signal intensities (SI) obtained from ROIs of the multiphase T1WI were used to calculate relative liver enhancement (RLE). The interobserver agreement of RLE and quantified T2 signal was calculated using Bland–Altman analysis. RLE assessed for both T2 hyperintense (RLEhyper) and T2 isointense (RLEiso) areas were compared in patients and controls (RLEhealthy). Results The interobserver agreement of RLE in affected hyperintense areas (bias −0.77, limits of agreement −51.7 to 50.1) was superior to the quantification of T2 signal only in these areas (bias −3.35, limits of agreement −162.4 to 155.7). The RLEhyper (86.2±9.7%) was higher than the RLEiso (59.8±6.2%, p=0.03) and the RLEhealthy (53.2±2.7%, p=0.002). The mean RLEiso was not significantly different from the RLEhealthy (p=0.3). Conclusion The extracellular gadolinium-based RLE of T2 hyperintense areas could be a useful add-on for routine follow up MRI in the detection of early inflammatory changes, possibly preceding formation of fibrotic scarring in PSC patients, if validated in larger cohorts.

Objectives To evaluate the accuracy of assessment of neurovascular bundle (NVB) infiltration using multiparametric magnetic resonance imaging (mpMRI) and PI-RADS V2 prior to prostatectomy. Methods The ethics committee approved this retrospective study with waiver of informed consent. N = 198 consecutive patients with biopsy proved cancer underwent standardized mpMRI at 3T prior to surgery. NVB infiltration was assessed for each side (a total of 396). Maximum PI-RADS V2 scores were determined for the posterolateral areas adjacent to the NVBs. Imaging results were correlated with postoperative pathology and standard descriptive statistics were calculated. Results Overall T-staging sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of mpMRI were 64.4%, 89.2%, 82.4%, 76.2% and 78.3%, respectively. In 396 cases NVB infiltration was predicted with 75.3%, 94.0%, 80.2%, 92.1 % and 89.4 % sensitivity, specificity, PPV, NPV and accuracy, respectively. Analyses of 396 NVB and their adjacent PI-RADS V2 scores with pathology revealed significantly more NVB-infiltrations in suspect scores of 5 and 4 vs. uncertain scores of 3–1 (81/264 vs. 16/132, p = 0.0001). Considering scores higher than 3 as a criterion of infiltration demonstrated moderate sensitivity and poor specificity (83.5% and 38.8%, respectively). Interobserver agreement of a second reading of a random sample was good (κ = 0.64) for NVB infiltrations and moderate (κ = 0.59) for PI-RADS V2. Conclusions Assessment of infiltration of the neurovascular bundles using mpMRI has valuable diagnostic performance, yet PI-RADS V2 Scores demonstrate limited eligibility. Combined findings offer crucial information for the planning of prostatectomy.

Diagnosing acute pancreatitis (AP) may be challenging in patients with acute abdominal pain but missing threefold increased serum lipase levels (Lip-). This studyaims both to characterize these patients using clinical, radiological and mortality data, and to assess the group of patients who need contrast-enhanced computed tomography (CECT).In this retrospective, IRB approved study 234 consecutive patients with AP were investigated. Inclusion criteria were single (SAP) and recurrent attacks (RAP) of AP and CECT ≥72h after onset of symptoms. Severity of AP was assessed by C-reactive protein at 48h after hospital admission and using 3 CT-based scores (CTSI, mCTSI, EPIC) by 2 observers. Mortality rates from pancreatic and non-pancreatic causes were noted with regard to lipase increase. Results were compared with paired t-test and Wilcoxon signed-rank test.64/234 (27%) patients belonged to Lip- group and 170/234 (73%) patients were allocated to Lip+ group. Significantly more male patients (78% in Lip- vs. 63% in Lip+, p0.05) with RAP (63% in Lip- vs. 21% in Lip+, p0.001) were observed in the Lip- group. EPIC was significantly lower in Lip- group compared to Lip+ group (3(IQR 2-5) vs. 2(IQR 1-3), p0.001). Mortality from pancreatic and non-pancreatic causes was comparable in Lip- and Lip+ group (pancreatic causes: 9% vs. 6%, p=0.60; nonpancreatic causes: 8% vs. 5%, p=0.58).27% of all patients with AP presented without threefold increase of lipase levels. Thus, they would be underdiagnosed without confirming CECT, which revealed significantly lower counts of pleural effusions and ascites. Male patients with RAP were found significantly more often among the Lip- group. Hence, they would benefit the most from CECT for diagnosing AP.

When one of the two hemispheres directs visuospatial attention to some contralateral location, this may imply that inhibition is exerted on the other hemisphere. In the dual rapid serial visual presentation task, two targets (T1 and T2) occur among two different visual streams, rapidly presented left and right. We replaced the standard letter distractors in one stream by “easy symbols” (ESy; easily distinguished from targets), to facilitate T1 identification. If interhemispheric inhibition is deployed and released, this facilitation of one hemisphere's task should reduce its inhibitory effect on the other hemisphere, leading to improved T2 identification by the other hemisphere. This prediction was confirmed in three experiments. Furthermore, event-related EEG potentials did not only show a constant bias of allocated attention between ESy and standard streams, with letters evoking visual potentials earlier than ESy, but also short-term enlargement of this effect in the pair of distractors that followed T1. Taken together, these results support the notion of interhemispheric inhibition in visuospatial attention.

Purpose To investigate the feasibility of sub-milliSievert CT of the cervical spine in fresh human cadavers using a standard-dose (SD) and four different reduced-dose (RD) protocols reconstructed with filtered back projection (FBP) and iterative reconstruction (IR). Methods The cervical spine of 29 cadavers was examined using different RDCT protocols with decreasing reference tube currents (RDCT-1:70 mAs; RDCT-2:50 mAs; RDCT-3:30 mAs; RDCT-4:10 mAs) at 140 kV. A clinical SDCT (160 mAs, 120 kV) served as reference. Raw data were reconstructed using FBP and two increasing levels of IR (IRL4&6). Images of the upper (C1–4) and lower (C5–7) cervical spine were evaluated for image quality, diagnostic acceptability and visibility of anatomical structures according to a 5-point-scale. Results Image quality of the upper cervical spine was diagnostically acceptable for all protocols using FBP and IR except for RDCT-4 with FBP. Image quality of the lower cervical spine was rated as non-diagnostic in RDCT-3 with FBP and RDCT-4 with FBP and IR. RDCT-3 with IR was the most reduced dose CT protocol allowing diagnostically acceptable image quality for both upper and lower cervical spine in all cadavers. RDCT protocols achieved significantly reduced effective radiation doses (SDCT: 1.5 ± 0.7 mSv; RDCT-1:1 ± 0.6 mSv; RDCT-2:0.7 ± 0.4 mSv; RDCT-3:0.4 ± 0.2 mSv; RDCT-4:0.2 ± 0.1 mSv; p Conclusion Diagnostically acceptable sub-milliSievert CT of the cervical spine is feasible with a low reference tube current at 140 kV using iterative reconstruction and could be suitable for isolated cervical trauma in cooperative patients.

Objectives The purpose of the retrospective study was to evaluate the additional value of dual-phase multidetector computed tomography (MDCT) protocols over a single-phase protocol on initial MDCT in patients with acute pancreatitis using three CT-based pancreatitis severity scores with regard to radiation dose. Methods In this retrospective, IRB approved study MDCT was performed in 102 consecutive patients (73 males; 55years, IQR48–64) with acute pancreatitis. Inclusion criteria were CT findings of interstitial edematous pancreatitis (IP) or necrotizing pancreatitis (NP) and a contrast-enhanced dual-phase (arterial phase and portal-venous phase) abdominal CT performed at ≥72 h after onset of symptoms. The severity of pancreatic and extrapancreatic changes was independently assessed by 2 observers using 3 validated CT-based scoring systems (CTSI, mCTSI, EPIC). All scores were applied to arterial phase and portal venous phase scans and compared to score results of portal venous phase scans, assessed ≥14 days after initial evaluation. For effective dose estimation, volume CT dose index (CTDIvol) and dose length product (DLP) were recorded in all examinations. Results In neither of the CT severity scores a significant difference was observed after application of a dual-phase protocol compared with a single-phase protocol (IP: CTSI: 2.7 vs. 2.5, p = 0.25; mCTSI: 4.0 vs. 4.0, p = 0.10; EPIC: 2.0 vs. 2.0, p = 0.41; NP: CTSI: 8.0 vs. 7.0, p = 0.64; mCTSI: 8.0 vs. 8.0, p = 0.10; EPIC: 3.0 vs. 3.0, p = 0.06). The application of a single-phase CT protocol was associated with a median effective dose reduction of 36% (mean dose reduction 31%) compared to a dual-phase CT scan. Conclusions An initial dual-phase abdominal CT after ≥72 h after onset of symptoms of acute pancreatitis was not superior to a single-phase protocol for evaluation of the severity of pancreatic and extrapancreatic changes. However, the effective radiation dose may be reduced by 36% using a single-phase protocol.

Aim To compare standard (SD-) and reduced-dose computed tomography (RD-CT) in combination with iterative reconstruction (IR) in emergency patients with suspected lumbar spine fracture. Material and methods Forty emergency patients with suspected lumbar spinal disorder who underwent RD-CT and 40 body mass index-matched patients undergoing SD-CT were enrolled in this retrospective study. Raw data for RD-CT were reconstructed using two increasing IR levels (IRL) 4 and 6, while SD-CT was reconstructed with IRL3. Two radiologists assessed image quality, image noise, and reader confidence in interpreting findings of spinal fractures in a blinded manner. Results Effective radiation dose was reduced by 50% using RD-CT. Overall subjective image quality (SIQ) was high for both protocols and slightly superior in the RD-CT protocol for both IRL compared to SD-CT. The detection rate of spinal disorders was high for both protocols with a high interobserver agreement. Conclusion RD-CT with higher levels of IR results in substantial dose reduction of 50% in lumbar spine CT while maintaining an excellent subjective image quality resulting in a high diagnostic confidence.