Standardized 18F-FDG PET/CT radiomic features provide information on PD-L1 expression status in treatment-naïve patients with non-small cell lung cancer.

PURPOSE: To study the relationship between standardized 18F-FDG PET/CT radiomic features and clinicopathological variables and programmed death ligand-1 (PD-L1) expression status in non-small cell lung cancer (NSCLC) patients. METHODS: 58 NSCLC patients with preoperative 18F-FDG PET/CT scans and postoperative results of PD-L1 expression were retrospectively analysed. A standardized, open-source software was used to extract 86 radiomic features from PET and low-dose CT images. Univariate analysis and multivariate logistic regression were used to find independent predictors of PD-L1 expression. The Area Under the Curve (AUC) of receiver operating characteristic (ROC) curve was used to compare the ability of variables and their combination in predicting PD-L1 expression. RESULTS: Multivariate logistic regression resulted in the PET radiomic feature GLRLM_LGRE (Odds Rate (OR): 0.300 vs 0.114, 95% confidence interval (CI): 0.096-0.931 vs 0.021-0.616, in NSCLC and adenocarcinoma respectively) and the CT radiomic feature GLZLM_SZE (OR: 3.338 vs 7.504, 95%CI: 1.074-10.375 vs 1.382-40.755, in NSCLC and adenocarcinoma respectively), being independent predictors of PD-L1 status. In NSCLC group, after adjusting for gender and histology, the PET radiomic feature GLRLM_LGRE (OR: 0.282, 95%CI: 0.085-0.936) remained an independent predictor for PD-L1 status. In the adenocarcinoma group, when adjusting for gender the PET radiomic feature GLRLM_LGRE (OR: 0.115, 95%CI: 0.021-0.631) and the CT radiomic feature GLZLM_SZE (OR: 7.343, 95%CI: 1.285-41.965) remained associated with PD-L1 expression. CONCLUSION: NSCLC and adenocarcinoma with PD-L1 expression show higher tumour heterogeneity. Heterogeneity-related 18F-FDG PET and CT radiomic features showed good ability to non-invasively predict PD-L1 expression.

Evaluation of superficial femoral artery-lesions after percutaneous transluminal angioplasty: color-coded summation images vs. monochromatic digital subtraction angiography.

BACKGROUND: Percutaneous transluminal angioplasty (PTA) is increasingly requested in the therapy of peripheral arterial occlusive disease. The evaluation of the technical result after balloon angioplasty with regard to bailout stenting is highly dependent on the operators´ subjective assessment and mainly based on the monochromatic digital subtraction angiography (DSA) images. The aim of this study was to compare color-coded single image as a novel diagnostic tool with monochromatic DSA for the analysis of flow limitation and need for stent implantation after PTA of superficial femoral artery (SFA) stenoses. METHODS: During a period of 18 months, 213 SFA lesions were treated by PTA with a standard balloon in 170 patients, resulting in a total of 193 endovascular procedures. The median age of the patients was 77 years (range, 35-96 years). Median length of the treated lesions was 10.5 cm (range, 1.0-50 cm). Three interventional radiologists retrospectively evaluated the results of balloon angioplasty with monochromatic as well as post-processed color-coded DSA images for flow limitations to decide if subsequent stent implantation was necessary. Consensus reading of two experienced interventional radiologists 2 months after the initial review served as reference standard to perform a receiver operating characteristics (ROC) analysis. RESULTS: ROC analysis for readers A, B and C showed area under the curve (AUC) values of 0.797, 0.865 and 0.804 for color-coded DSA and AUC values of 0.792, 0.843 and 0.872 for monochromatic DSA: a significant advantage of color-coded over conventional monochromatic DSA was not found for readers A and B (p > 0.05). Results of reader C were significantly better in the assessment of monochromatic images (p = 0.023). Diagnostic confidence using color-coded images was slightly higher than in monochromatic images (κ = 0.486 vs. κ = 0.459). CONCLUSIONS: In this study, color coded DSA did not reveal to be superior to conventional monochromatic DSA when evaluating results of PTA and when deciding whether stent implantation is necessary or not. This technology, however, requires further experiences with special regard to homogeneously trained radiologists and to the time requirement.

Correction to: Differing X-ray patterns in seronegative and seropositive rheumatoid arthritis.

The first and family names of the authors were interchanged and are now presented correctly. The original article has been corrected.

Differing X-ray patterns in seronegative and seropositive rheumatoid arthritis.

INTRODUCTION: Anti-citrullinated protein antibody (ACPA) and rheumatoid factor (RF) status are important predictors for rheumatoid arthritis (RA) erosivity. Qualitative differences on hand/feet radiographs have been described, indicating more carpal fusion in seronegative RA. This study explores these differences further using the total Sharp/van der Heijde score (TSS), digital X-ray radiogrammetry (DXR), and qualitative description. METHODS AND MATERIALS: Matched seronegative (ACPA negative, RF negative, snRA) and seropositive (ACPA, RF > 3xULN, spRA) were examined. TSS scores both for erosions and joint space narrowing (JSN) were registered separately and compared for both groups. Joint compartments and single joints were compared, using a heat map. The degree of carpal fusion was quantified 0-5. DXR measurements (bone mineral density, cortical thickness, bone width, metacarpal index) were determined for each hand separately. Finally, selected radiographs were examined unblinded to search for non-quantifiable differences. RESULTS: A total of 56 snRA and 57 spRA patients were examined. spRA patients had more erosions and joint space narrowing. Erosion load differed significantly between spRA and snRA in the foot and metacarpophalangeal joint, but not in the wrist or proximal interphalangeal joint compartments. Intracompartmental differences were greater in spRA. JSN scores were greater in spRA, in all compartments except wrist. Carpal fusion and DXR scores did not differ between the groups. The qualitative comparison showed that snRA patients displayed periarticular ossifications, carpal shortening, and sparing of the CMC joints, whereas spRA patients had more CMC damage and less shortening. CONCLUSION: X-ray manifestations in snRA and spRA are qualitatively and quantitatively different. This suggests pathophysiological differences between the two forms. Key Points • Seronegative and seropositive RA display qualitatively and quantitatively different X-ray patterns, suggesting differences in the underlying pathophysiological process. This is the first time that this has been shown in a systematic, quantitative fashion.

Left Ventricular Structure in Patients With Mild-to-Moderate CKD-a Magnetic Resonance Imaging Study.

INTRODUCTION: The high burden of left ventricular (LV) abnormalities in patients with advanced chronic kidney disease (CKD) is well established. However, less is known about the prevalence, patterns, and determinants of LV abnormalities in patients with early CKD. METHODS: We examined LV structure in 290 patients with a median estimated glomerular filtration rate (eGFR) of 51 ml/min per 1.73 m2 by magnetic resonance imaging (MRI). We explored associations with clinical and hemodynamic parameters, hydration (bioimpedance), endothelial function, inflammation (including C-reactive protein and tumor necrosis factor-α and its soluble receptors) and mineral bone disease (MBD) markers (including vitamin D, parathyroid hormone, α-klotho and fibroblast growth factor-23). RESULTS: Normal geometry was found in 56% of patients, dilation in 4%, concentric remodeling in 10%, and LV hypertrophy in 29%. Linear regression analysis revealed that greater LV mass was independently associated with male sex, greater body mass index (BMI), and higher 24-hour systolic blood pressure (24-hour SBP). Concentric remodeling was independently associated with age, male sex, higher 24-hour SBP, and greater hemoglobin levels. Surprisingly, neither hydration status, nor endothelial function, nor any of the inflammatory or MBD parameters added significantly to these models. CONCLUSION: Abnormal LV structure was found in almost one-half of the patients. Reducing BMI and 24-hour SBP and avoiding high hemoglobin concentrations appear to be the key factors to prevent abnormal LV remodeling in patients with mild-to-moderate CKD.

Increased myocardial sodium signal intensity in Conn's syndrome detected by 23Na magnetic resonance imaging.

AIMS: Sodium intake has been linked to left ventricular hypertrophy independently of blood pressure, but the underlying mechanisms remain unclear. Primary hyperaldosteronism (PHA), a condition characterized by tissue sodium overload due to aldosterone excess, causes accelerated left ventricular hypertrophy compared to blood pressure matched patients with essential hypertension. We therefore hypothesized that the myocardium constitutes a novel site capable of sodium storage explaining the missing link between sodium and left ventricular hypertrophy. METHODS AND RESULTS: Using 23Na magnetic resonance imaging, we investigated relative sodium signal intensities (rSSI) in the heart, calf muscle, and skin in 8 PHA patients (6 male, median age 55 years) and 12 normotensive healthy controls (HC) (8 male, median age 61 years). PHA patients had a higher mean systolic 24 h ambulatory blood pressure [152 (140; 163) vs. 125 (122; 130) mmHg, P < 0.001] and higher left ventricular mass index [71.0 (63.5; 106.8) vs. 55.0 (50.3; 66.8) g/m2, P = 0.037] than HC. Compared to HC, PHA patients exhibited significantly higher rSSI in the myocardium [0.31 (0.26; 0.34) vs. 0.24 (0.20; 0.27); P = 0.007], calf muscle [0.19 (0.16; 0.22) vs. 0.14 (0.13; 0.15); P = 0.001] and skin [0.28 (0.25; 0.33) vs. 0.19 (0.17; 0.26); P = 0.014], reflecting a difference of +27%, +38%, and +39%, respectively. Treatment of PHA resulted in significant reductions of the rSSI in the myocardium, calf muscle and skin by -13%, -27%, and -29%, respectively. CONCLUSION: Myocardial tissue rSSI is increased in PHA patients and treatment of aldosterone excess effectively reduces rSSI, thus establishing the myocardium as a novel site of sodium storage in addition to skeletal muscle and skin.

Interdisciplinary complication management of dislodged lumbar interbody spacer in pulmonary artery.

We report the case of an intraoperatively dislodged transforaminal lumbar interbody fusion spacer with creation of a traumatic arteriovenous fistula and device migration to the pulmonary artery. Successful minimally invasive angiographic retrieval of the spacer is discussed with special reference to angiographic and surgical treatment strategies and pitfalls.

Blood Pressure Pattern and Target Organ Damage in Patients With Chronic Kidney Disease.

In patients with chronic kidney disease, data on blood pressure (BP) pattern and its association with target organ damage, which indicates elevated cardiovascular risk, are sparse. In 305 treated hypertensive chronic kidney disease patients, we assessed BP pattern, left ventricular mass (magnetic resonance imaging), intima-media thickness (ultrasound), 24-hour-pulse wave velocity and 24-hour-central augmentation index (Mobil-O-Graph). Controlled hypertension (normal office and ambulatory BP) was found in 41% and sustained uncontrolled hypertension (elevated office and ambulatory BP) in 30% of patients. Misclassification of BP status occurred in 29%: white coat uncontrolled hypertension (elevated office but normal ambulatory BP) was detected in 11% and masked uncontrolled hypertension (normal office but elevated ambulatory BP) in 18% of patients. Left ventricular mass was increased in white coat uncontrolled hypertension (+11.2 g), masked uncontrolled hypertension (+9.4 g), and sustained uncontrolled hypertension (+16.6 g) compared with controlled hypertension. Intima-media thickness was similar across all 4 BP groups. Twenty-four hour-pulse wave velocity and 24-hour-central augmentation index were increased in masked uncontrolled hypertension (+0.5 m/sec and +2.5%) and sustained uncontrolled hypertension (+0.5 m/sec and +2.9%) compared with controlled hypertension. In conclusion, based on office BP measurements, misclassification of true BP status occurred in almost one-third of chronic kidney disease patients. Both types of misclassification (white coat uncontrolled hypertension and masked uncontrolled hypertension) were associated with parameters of target organ damage. Ambulatory BP monitoring should be used routinely to identify chronic kidney disease patients at high cardiovascular risk.

EULAR recommendations for the use of imaging in large vessel vasculitis in clinical practice.

To develop evidence-based recommendations for the use of imaging modalities in primary large vessel vasculitis (LVV) including giant cell arteritis (GCA) and Takayasu arteritis (TAK). European League Against Rheumatism (EULAR) standardised operating procedures were followed. A systematic literature review was conducted to retrieve data on the role of imaging modalities including ultrasound, MRI, CT and [18F]-fluorodeoxyglucose positron emission tomography (PET) in LVV. Based on evidence and expert opinion, the task force consisting of 20 physicians, healthcare professionals and patients from 10 EULAR countries developed recommendations, with consensus obtained through voting. The final level of agreement was voted anonymously. A total of 12 recommendations have been formulated. The task force recommends an early imaging test in patients with suspected LVV, with ultrasound and MRI being the first choices in GCA and TAK, respectively. CT or PET may be used alternatively. In case the diagnosis is still in question after clinical examination and imaging, additional investigations including temporal artery biopsy and/or additional imaging are required. In patients with a suspected flare, imaging might help to better assess disease activity. The frequency and choice of imaging modalities for long-term monitoring of structural damage remains an individual decision; close monitoring for aortic aneurysms should be conducted in patients at risk for this complication. All imaging should be performed by a trained specialist using appropriate operational procedures and settings. These are the first EULAR recommendations providing up-to-date guidance for the role of imaging in the diagnosis and monitoring of patients with (suspected) LVV.

Single-shot late Gd enhancement imaging of myocardial infarction with retrospectively adjustable contrast and heart-phase.

OBJECT: To enable a retrospective adjustment of image contrast and heart phase in inversion recovery prepared late gadolinium enhancement (LE) imaging in the myocardium. MATERIALS AND METHODS: After one inversion pulse, unsegmented data were acquired over multiple cardiac cycles using a radial spoiled gradient-echo sequence with golden angle increments between subsequent readouts. Model-based acceleration of parameter mapping (MAP) was combined with an image registration technique ("MOCO-MAP") to enable the reconstruction of images with arbitrary inversion time TI. RESULTS: MOCO-MAP allowed the reconstruction of LE images with arbitrary TI for arbitrary cardiac phases in four patients suffering from myocardial infarction. Regions with LE agreed well between the MOCO-MAP and the segmented techniques typically applied in clinical routine. CONCLUSIONS: MOCO-MAP delivers LE images with arbitrary and thus retrospectively optimized contrast between vital and diseased tissue, without the need for time-consuming TI scouting.

Impact of advanced modeled iterative reconstruction on interreader agreement in coronary artery measurements.

OBJECTIVES: To evaluate the influence of advanced modeled iterative reconstruction (ADMIRE) on coronary artery computed tomography angiography (cCTA) measurements in comparison to filtered back projection (FBP). MATERIAL AND METHODS: Phantom scans and coronary CTA studies of 27 patients were acquired with a third generation dual-source CT scanner. Images were reconstructed using FBP and ADMIRE. Phantom measurements were used as reference standard. In patient studies, representative axial slices of each coronary artery segment without (n=308) and with coronary plaques (n=40) were assessed in identical positions for comparison of FBP and ADMIRE reconstructions. Image analyses included quality assessment, phantom and coronary artery measurements, plaque analysis, and interreader agreement of two independent and blinded readers. RESULTS: Mean image noise was lower on ADMIRE reconstructions with 31.3±9.9 HU compared to 55.9±15.7 HU on FBP reconstructions (p<0.001). Measurement precision and interreader agreement of both observers were assessed satisfactorily on phantom images in comparison to the full width half maximum method. In patients, correlation of lumen diameters of both observers improved using ADMIRE with a Pearson's r=0.987 (95% confidence interval [CI], 0.983-0.989; p<0.001) compared to FBP images with r=0.939 (95% CI, 0.924-0.951; p<0.001). Applying ADMIRE, agreement of both observers for lumen diameter measurements significantly increased (p<0.001). This was also observed for the degree of stenosis (p<0.001) with r=0.560 using FBP (95% CI, 0.301-0.742) and with r=0.818 using ADMIRE (95% CI, 0.680-0.900). Plaque density measurements correlated closely with a Pearson's r of 0.951 in FBP (95% CI, 0.909-0.974) and 0.967 in ADMIRE (95% CI, 0.939-0.983). CONCLUSIONS: Advanced modeled iterative reconstruction significantly improves coronary artery assessment in coronary CTA in comparison to FBP by improved image quality due to image noise removal. This renders improved interobserver agreement for coronary lumen diameter and degree of stenosis measurements without influencing mean plaque attenuation.

Diagnostic value of contrast-enhanced magnetic resonance angiography in large-vessel vasculitis.

OBJECTIVE: To evaluate contrast-enhanced magnetic resonance angiography (MRA) in diagnosis of inflammatory aortic involvement in patients with clinical suspicion of large-vessel vasculitis. PATIENTS AND METHODS: Seventy-five patients, mean age 62 years (range 16-82 years), 44 female and 31 male, underwent gadolinium-enhanced MRA and were evaluated retrospectively. Thoracic MRA was performed in 32 patients, abdominal MRA in 7 patients and both thoracic and abdominal MRA in 36 patients. Temporal arterial biopsies were obtained from 22/75 patients. MRA positivity was defined as increased aortic wall signal in late gadolinium-enhanced axial turbo inversion recovery magnitude (TIRM) series. The influence of prior glucocorticoid intake on MRA outcome was evaluated. RESULTS: MRA was positive in 24/75 patients, with lesions located in the thorax in 7 patients, the abdomen in 5 and in both thorax and abdomen in 12. Probability for positive MRA after glucocorticoid intake for more than 5 days before MRA was reduced by 89.3%. Histology was negative in 3/10 MRA-positive patients and positive in 5/12 MRA-negative patients. All 5/12 histology positive / MRA-negative patients had glucocorticoids for >5 days prior to MRA and were diagnosed as having vasculitis. Positive predictive value for MRA was 92%, negative predictive value was 88%. CONCLUSIONS: Contrast-enhanced MRA reliably identifies large vessel vasculitis. Vasculitic signals in MRA are very sensitive to glucocorticoids, suggesting that MRA should be done before glucocorticoid treatment.

Dual-Energy CTA in Patients with Symptomatic Peripheral Arterial Occlusive Disease: Study of Diagnostic Accuracy and Impeding Factors.

Purpose The purpose of this study was to assess the diagnostic performance of dual-energy CT angiography (DE-CTA) in patients with symptomatic peripheral artery occlusive disease (PAOD) and to identify factors that impede its diagnostic accuracy. Materials and Methods Dual-source DE-CTA scans of the lower extremities of 94 patients were retrospectively compared to the diagnostic reference standard, digital subtraction angiography (DSA). Two independent observers assessed PAOD incidence, image quality, artifacts, and diagnostic accuracy of DE-CTA in 1014 arterial segments on axial, combined 80/140 kVp reconstructions and on 3 D maximum intensity projections (MIP) after automated bone and plaque removal. The impact of calcifications, image quality, and image artifacts on the diagnostic accuracy was evaluated using Fisher's exact test. Furthermore, interobserver agreement was analyzed. Results Two observers achieved sensitivities of 98.0 % and 93.9 %, respectively, and specificities of 75.0 % and 66.7 %, respectively, for detecting stenoses of > 50 % of the lower extremity arteries. Calcifications impeded specificity, e. g. from 81.2 % to 46.2 % for reader 1 (p < 0.001). Specificity increased with higher image quality, e. g. from 70.0 % to 76.4 % for reader 1 (p < 0.001). Artifacts decreased the specificity of reader 2 (p < 0.001). The overall interobserver agreement ranged between moderate and substantial for stenosis detection and calcified plaques. Conclusion DE-CTA is accurate in the detection of arterial stenoses of > 50 % in symptomatic PAOD patients. Calcified atherosclerotic plaques, image quality, and artifacts may impede specificity. Key Points: · Sensitivities of DE-CTA were 98.0 and 93.9 %, specificities 75.0 % and 66.7 %.. · Interobserver agreement was moderate to substantial for stenosis and plaque detection.. · Calcified atherosclerotic plaques, image quality, and artifacts may impede specificity.. Citation Format · Klink T, Wilhelm T, Roth C et al. Dual-Energy CTA in Patients with Symptomatic Peripheral Arterial Occlusive Disease: Study of Diagnostic Accuracy and Impeding Factors. Fortschr Röntgenstr 2017; 189: 441 - 452.

Contrast agents and ionization with respect to safety for patients and doctors.

In hemodialysis patients, radiographic imaging with iodinated contrast medium (ICM) application plays a central role in the diagnosis and/or follow-up of disease-related conditions. Therefore, safety aspects concerning ICM administration and radiation exposure have a great impact on this group of patients. Current hardware and software improvements including the design and synthesis of modern contrast compounds allow the use of very small amounts of ICM in concert with low radiation exposure. Undesirable ICM side effects are divided into type A (predictable reactions such as heat feeling, headache, and contrast-induced acute kidney injury, for example) and type B (nonpredictable or hypersensitivity) reactions; this chapter deals with the latter. The first onset cannot be prevented. To prevent hypersensitivity upon reexposure of ICM, an allergological workup is recommended. If this is not possible and ICM is necessary, the patient should receive a premedication (H1 antihistamine with or without corticosteroids). Current imaging hardware and software improvements (e.g. such as additional filtration of the X-ray beam) allow the use of very small amount of ICM and small X-ray doses. Proper communication among the team involved in the treatment of a patient may allow to apply imaging protocols and efficient imaging strategies limiting radiation exposure to a minimum. Practical recommendations will guide the reader how to use radiation and ICM efficiently to improve both patient and staff safety.

Diagnosis of cardiac metastasis from cervical cancer in a 33-year-old patient using multimodal imaging studies: a case report and literature review.

We report a case of a 33-year-old woman with emergency admission due to dyspnoea and fever. History included squamous cell carcinoma of the cervix in complete remission. Contrast-enhanced computed tomography (CT) scanning of the chest, which was indicated to rule out pneumonia, revealed an infiltrative cardiac mass. Further assessment of the tumour by echocardiography and cardiac magnetic resonance imaging (MRI) showed transmural infiltration of the apical interventricular septum with a mass extending into the left and right ventricle cavities. The mass was highly suspicious for a cardiac metastasis. Cardiac metastases from cervical cancer are extremely rare. Recurrence of cervical carcinoma involving the heart should be considered even after a curative therapy approach. Non-invasive imaging plays a paramount role in investigating cardiac masses. Echocardiography, CT and MRI are complementary imaging modalities for complete work-up of intracardiac lesions.