Applicability and accuracy of pretest probability calculations implemented in the NICE clinical guideline for decision making about imaging in patients with chest pain of recent onset.

OBJECTIVES: To analyse the implementation, applicability and accuracy of the pretest probability calculation provided by NICE clinical guideline 95 for decision making about imaging in patients with chest pain of recent onset. METHODS: The definitions for pretest probability calculation in the original Duke clinical score and the NICE guideline were compared. We also calculated the agreement and disagreement in pretest probability and the resulting imaging and management groups based on individual patient data from the Collaborative Meta-Analysis of Cardiac CT (CoMe-CCT). RESULTS: 4,673 individual patient data from the CoMe-CCT Consortium were analysed. Major differences in definitions in the Duke clinical score and NICE guideline were found for the predictors age and number of risk factors. Pretest probability calculation using guideline criteria was only possible for 30.8 % (1,439/4,673) of patients despite availability of all required data due to ambiguity in guideline definitions for risk factors and age groups. Agreement regarding patient management groups was found in only 70 % (366/523) of patients in whom pretest probability calculation was possible according to both models. CONCLUSIONS: Our results suggest that pretest probability calculation for clinical decision making about cardiac imaging as implemented in the NICE clinical guideline for patients has relevant limitations. KEY POINTS: • Duke clinical score is not implemented correctly in NICE guideline 95. • Pretest probability assessment in NICE guideline 95 is impossible for most patients. • Improved clinical decision making requires accurate pretest probability calculation. • These refinements are essential for appropriate use of cardiac CT.

Correction to: Applicability and accuracy of pretest probability calculations implemented in the NICE clinical guideline for decision making about imaging in patients with chest pain of recent onset.

The original version of this article, published on 19 March 2018, unfortunately contained a mistake. The following correction has therefore been made in the original: The names of the authors Philipp A. Kaufmann, Ronny Ralf Buechel and Bernhard A. Herzog were presented incorrectly.

In vivo analysis of the vascular pattern of the superficial temporal artery based on digital subtraction angiography.

BACKGROUND: Existing anatomic descriptions of the superficial temporal artery (STA) are mainly based on cadaver studies and do not accurately reflect the in vivo situation. In this study, the anatomical course and branching pattern of the STA were analyzed with digital subtraction angiographies (DSAs). METHODS: DSAs of 93 Caucasian individuals between 16- and 79-years old were retrospectively analyzed regarding the course and branching pattern of the STA as well as surgically relevant inner diameters and lengths of its main branches. RESULTS: In total, 11 variations in the branching pattern of the terminal STA were found. About 89% of the examined individuals demonstrated the classic variation in which the main trunk of the STA bifurcates into a single frontal and parietal branch. In 60% of cases with an existing bifurcation, the division of the main trunk of the STA was located above the zygoma. The mean inner diameters of the STA main trunk, the frontal branch and the parietal branch were 2.4 ± 0.6 mm, 1.3 ± 0.6 mm and 1.2 ± 0.4 mm, respectively. The surgically relevant "working lengths" of the frontal and parietal branches above the upper margin of the zygoma up to an inner diameter of 1 mm were 106.4 ± 62.1mm and 99.7 ± 40.9 mm, respectively. CONCLUSIONS: The common variations of the branching pattern of the STA are described in this study. Furthermore, surgically relevant inner diameters and lengths of the main branches of the STA are determined. These findings should improve our understanding of the suitability and usefulness of the STA for various surgical procedures.

Association between linear measurements of corpus callosum and gait in the elderly.

PURPOSE: Segmentation and diffusion-tensor-imaging of the corpus callosum (CC) have been linked to gait impairment. However, such measurements are impracticable in clinical routine. The purpose of this study was to evaluate the association between simple linear measurements of CC thickness with gait. METHODS: Two hundred and seventy-two community-dwelling subjects underwent neurological assessment and brain MRI. Mid-sagittal reformats of T1-weighted images were used to determine CC thickness. The association of measurements with clinical evaluation of gait was assessed by multivariate regression, controlling for numerous clinical and imaging confounders. Differences in CC thickness were, moreover, compared between subgroups with no, moderate or severe impairment of gait. RESULTS: In univariate analyses, thickness of the genu and body of CC but not the splenium were associated with postural stability (P < 0.01). Multivariate regression revealed thickness of CC genu as the only imaging variable independently associated with gait (P = 0.01). Genu thickness was significantly different between subjects with high and low (P = 0.0003) or high and moderate (P = 0.001) risk of fall. CONCLUSION: Atrophy of the CC genu is an imaging marker of gait impairment in the elderly suggesting higher risk of fall. Simple linear measurements of CC can help in MRI evaluation of patients with gait impairment. KEY POINTS: • Regional atrophy of the corpus callosum reflects disruption of gait regulation • Genu thickness on cranial MRI is an independent marker of gait impairment • Findings help in the MRI evaluation of patients with gait impairment.

Imaging findings in tick-borne encephalitis with differential diagnostic considerations.

OBJECTIVE: The purpose of this article is to provide a practical review of the spectrum of imaging findings in patients with tick-borne encephalitis (TBE) and to address possible differential diagnoses. CONCLUSION: Imaging findings in TBE resemble those of other infections, such as meningoencephalitis. However, a predilection for the thalami, basal ganglia, cerebellum, and anterior horns of the spinal cord suggests the possibility of TBE.

Early response assessment in patients with multiple myeloma during anti-angiogenic therapy using arterial spin labelling: first clinical results.

OBJECTIVE: To determine if arterial-spin-labelling (ASL) MRI can reliably detect early response to anti-angiogenic therapy in patients with multiple myeloma by comparison with clinical/haematological response. METHODS: Nineteen consecutive patients (10 men; mean age 63.5 ± 9.1 years) were included in the present study. Inclusion criteria were diagnosis of stage III multiple myeloma and clinical indication for therapeutical administration of bortezomib or lenalidomide. We performed MRI on 3.0T MR in the baseline setting, 3 weeks after onset of therapy and after 8 weeks. Clinical responses were determined on the basis of international uniform response criteria in correlation with haematological parameters and medium-term patient outcome. MRI studies were performed after approval by the local institutional review board. RESULTS: Fifteen patients responded to anti-myeloma therapy; 4/19 patients were non-responders to therapy. Mean tumour perfusion assessed by ASL-MRI in a reference lesion was 220.7 ± 132.5 ml min(-1) 100 g(-1) at baseline, and decreased to 125.7 ± 86.3 (134.5 ± 150.9) ml min(-1) 100 g(-1) 3 (8) weeks after onset of therapy (P < 0.02). The mean decrease in paraproteinaemia at week 3 (8) was 52.3 ± 47.7% (58.2 ± 58.7%), whereas ß2-microglobulinaemia decreased by 20.3 ± 53.1% (23.3 ± 57.0%). Correlation of ASL perfusion with outcome was significant (P = 0.0037). CONCLUSION: ASL tumour perfusion measurements are a valuable surrogate parameter for early assessment of response to novel anti-angiogenic therapy.

Dual-energy computed tomography: is there a penalty in image quality and radiation dose compared with single-energy computed tomography?

OBJECTIVE: To assess dose and image quality of dual-energy (DE) mixed images in comparison to single-energy (SE) images. METHODS: A phantom containing iodine contrast inserts was scanned using SE and DE protocols. Dual-energy mixed images were reconstructed with varying composition ratios (ratio describing the contribution of 80 and 140 data in the mixed images). Image noise, iodine contrast, and contrast-to-noise ratios (CNRs) were assessed inside and outside the central field of view (FoV). RESULTS: With the default composition ratio (0.3), noise and contrast were comparable between both protocols in the central FoV. Peripherally, DE image noise exceeded noise in SE images; CNR in the periphery was lower in the DE images. The highest CNR was found for a composition ratio of 0.5 to 0.9, exceeding the CNR of SE images. CONCLUSIONS: Dual-energy mixed images offer an image quality comparable to SE images within the central FoV at comparable dose levels. In the peripheral FoV, image quality is decreased. By optimizing the composition ratio in the DE mixed images, higher CNRs than in the SE images can be achieved, leading to a dose reduction potential.

Semi-automatic assessment of global left ventricular function and left ventricular parameters with dual-source computed tomography: comparison with invasive angiography.

This study assesses the global left ventricular function and volumes using dual-source computed tomography (DSCT) with improved temporal resolution (83 ms) by use of a semi-automatic software tool in comparison to invasive angiography (IVA). One hundred patients scheduled for invasive coronary angiography because of suspected or known coronary artery disease (80 men; 20 women, mean age 62 +/- 10 years) were additionally examined by DSCT. Global left ventricular function (LVF), left ventricular end-diastolic volume (LVEDV), end-systolic volume (LVESV), and stroke volume (SV) were calculated by the use of semi-automatic post-processing software and results compared with those of IVA. Bland-Altman analysis revealed a good concordance between DSCT and IVA in terms of LVF: Pearson's r 0.78, confidence interval [CI] 0.68-0.86, P < 0.0001, bias 7.1% +/- 9.1%. The same was true for LVESV (Pearson's r 0.78, CI 0.67-0.85, P < 0.0001, bias 15.0 +/- 21.0 ml), whereas the agreement for LVEDV and SV was only moderate (LVEDV: Pearson's r 0.59, CI 0.43-0.72, P < 0.0001, bias 13.0 +/- 18.1 ml; SV: Pearson's r 0.47, CI 0.28-0.62, P < 0.0001, bias -1.4 +/- 28.4 ml). Semi-automatic evaluation of left ventricular parameters with DSCT revealed good correlation for LVF and LVESV, whereas LVEDV and SV showed only a moderate correlation. Moreover, LVF is systematically underestimated by DSCT.

Quantitative parameters to compare image quality of non-invasive coronary angiography with 16-slice, 64-slice and dual-source computed tomography.

Multi-slice computed tomography (MSCT) is a non-invasive modality to visualize coronary arteries with an overall good image quality. Improved spatial and temporal resolution of 64-slice and dual-source computed tomography (DSCT) scanners are supposed to have a positive impact on diagnostic accuracy and image quality. However, quantitative parameters to compare image quality of 16-slice, 64-slice MSCT and DSCT are missing. A total of 256 CT examinations were evaluated (Siemens, Sensation 16: n = 90; Siemens Sensation 64: n = 91; Siemens Definition: n = 75). Mean Hounsfield units (HU) were measured in the cavum of the left ventricle (LV), the ascending aorta (Ao), the left ventricular myocardium (My) and the proximal part of the left main (LM), the left anterior descending artery (LAD), the right coronary artery (RCA) and the circumflex artery (CX). Moreover, the ratio of intraluminal attenuation (HU) to myocardial attenuation was assessed for all coronary arteries. Clinical data [body mass index (BMI), gender, heart rate] were accessible for all patients. Mean attenuation (CA) of the coronary arteries was significantly higher for DSCT in comparison to 64- and 16-slice MSCT within the RCA [347 +/- 13 vs. 254 +/- 14 (64-MSCT) vs. 233 +/- 11 (16-MSCT) HU], LM (362 +/- 11/275 +/- 12/262 +/- 9), LAD (332 +/- 17/248 +/- 19/219 +/- 14) and LCX (310 +/- 12/210 +/- 13/221 +/- 10, all p < 0.05), whereas there was no significant difference between DSCT and 64-MSCT for the LV, the Ao and My. Heart rate had a significant impact on CA ratio in 16-slice and 64-slice CT only (p < 0.05). BMI had no impact on the CA ratio in DSCT only (p < 0.001). Improved spatial and temporal resolution of dual-source CT is associated with better opacification of the coronary arteries and a better contrast with the myocardium, which is independent of heart rate. In comparison to MSCT, opacification of the coronary arteries at DSCT is not affected by BMI. The main advantage of DSCT lies with the heart rate independency, which might have a positive impact on the diagnostic accuracy.

Coronary plaque quantification by voxel analysis: dual-source MDCT angiography versus intravascular sonography.

OBJECTIVE: The purpose of this study was to evaluate a voxel-based analytic technique for quantification of noncalcified coronary artery plaque with intravascular sonography as a standard of reference. SUBJECTS AND METHODS: Intravascular sonography and dual-source MDCT angiography prospectively performed on 12 patients resulted in identification of 20 segments containing noncalcified plaque. Four of these segments were used to establish reference measurements of 0.6-mm proximal wall thickness with a 0-HU cutoff between the epicardial fat and outer wall and an individually adjusted threshold for the interface between the wall and lumen. With these data, consecutive circular layers of the outer wall were subtracted from a 3D volume to determine the plaque plus medial layer and the actual plaque volume in the other 16 segments. Accuracy of the voxel technique was assessed by comparing the results with intravascular sonographic findings. RESULTS: Both the total plaque burden (plaque plus medial layer) and the actual plaque volume had good concordance with intravascular sonographic findings (49.6 +/- 20 mm (3) vs 56.7 +/- 23.6 mm (3), p = 0.076; 26.5 +/- 14.8 mm (3) vs 30.9 +/- 15.3 mm (3), p = 0.09). Corresponding correlation coefficients were r = 0.76 and r = 0.79. The method had good reproducibility, the an intraclass correlation coefficients being 0.93 for total plaque burden and 0.90 for actual plaque volume. CONCLUSION: Voxel analysis can be used for accurate and reproducible quantification not only of plaque burden but also of actual plaque volume.

Pathologic fractures in patients with multiple myeloma undergoing bisphosphonate therapy: incidence and correlation with course of disease.

OBJECTIVE: The purposes of this study were single-center analysis of the incidence of pathologic fractures in patients with multiple myeloma undergoing bisphosphonate therapy and correlation of the occurrence of pathologic fractures with the course of disease. MATERIALS AND METHODS: One hundred ninety-one patients with multiple myeloma consecutively underwent unenhanced whole-body low-dose MDCT in parallel with hematologic follow-up. Only patients undergoing at least two whole-body low-dose MDCT examinations were included in this retrospective study, resulting in 561 survey intervals. The median analysis period per patient was 23 months (range, 3-53 months). Fracture incidence and the relation between newly occurring fractures and course of the disease were assessed. RESULTS: Forty-nine pathologic fractures were detected in 49 of the 561 survey intervals (8.7%) and in 36 of the 191 patients (19%). Fractures were found on MDCT images irrespective of disease course. They were found in 25 of 202 intervals (12.4%) of progressive disease, in 14 of 171 intervals (8.2%) of disease remission, and in 10 of 188 intervals (5.3%) of stable disease. The overall calculated annual incidence of pathologic fractures in patients with multiple myeloma was 14%. Eleven patients had more than one fracture, all of which were vertebral compression fractures. Three patients had three episodes of bone fracture, and eight patients had two episodes. CONCLUSION: Pathologic fractures in patients with multiple myeloma undergoing bisphosphonate therapy occur independently of myeloma activity and therefore should not be considered a sign of disease progression.

Dual-source CT: effect of heart rate, heart rate variability, and calcification on image quality and diagnostic accuracy.

PURPOSE: To prospectively evaluate the effect of heart rate, heart rate variability, and calcification on dual-source computed tomography (CT) image quality and to prospectively assess diagnostic accuracy of dual-source CT for coronary artery stenosis, by using invasive coronary angiography as the reference standard. MATERIALS AND METHODS: This study had local Ethics Committee approval; all patients gave informed consent. Patients who underwent bypass surgery were excluded; patients with coronary artery stent-grafts were included. One hundred patients (20 women, 80 men; mean age, 62 years +/- 10 [standard deviation]) known to have or suspected of having coronary artery disease underwent dual-source CT and invasive coronary angiography. Image quality was assessed. Accuracy of dual-source CT in depiction or exclusion of significant stenosis (>or=50%) was evaluated on a per-segment and per-patient basis. Effects of heart rate, heart rate variability, and calcification on image quality and accuracy were analyzed by using multivariate regression and were analyzed between subgroups of predictor variables. Simple regression was performed to calculate thresholds for adequate image quality. RESULTS: Mean heart rate was 64.9 beats per minute +/- 13.2, mean variability was 23.6 beats per CT examination +/- 36.2, and mean Agatston score was 786.5 +/- 965.9. Diagnostic image quality was obtained in 90.2% of segments. Sensitivity, specificity, and positive and negative predictive values for the presence of significant stenosis were, respectively, 91.1%, 92.0%, 75.4%, and 97.5% by segment and 100%, 81.5%, 93.6%, and 100% by patient. Image quality was significantly related to heart rate variability (P = .015) and calcification (P < .001); the number of nondiagnostic segments was significantly affected by calcification only. Calcification was the single factor with significant impact on diagnostic accuracy (P = .001). CONCLUSION: While dual-source CT resulted in heart-rate independent image quality, image quality remained prone to heart rate variability and calcification.

Tumor cell-derived and macrophage-derived cathepsin B promotes progression and lung metastasis of mammary cancer.

Proteolysis in close vicinity of tumor cells is a hallmark of cancer invasion and metastasis. We show here that mouse mammary tumor virus-polyoma middle T antigen (PyMT) transgenic mice deficient for the cysteine protease cathepsin B (CTSB) exhibited a significantly delayed onset and reduced growth rate of mammary cancers compared with wild-type PyMT mice. Lung metastasis volumes were significantly reduced in PyMT;ctsb(+/-), an effect that was not further enhanced in PyMT;ctsb(-/-) mice. Furthermore, lung colonization studies of PyMT cells with different CTSB genotypes injected into congenic wild-type mice and in vitro Matrigel invasion assays confirmed a specific role for tumor-derived CTSB in invasion and metastasis. Interestingly, cell surface labeling of cysteine cathepsins by the active site probe DCG-04 detected up-regulation of cathepsin X on PyMT;ctsb(-/-) cells. Treatment of cells with a neutralizing anti-cathepsin X antibody significantly reduced Matrigel invasion of PyMT;ctsb(-/-) cells but did not affect invasion of PyMT;ctsb(+/+) or PyMT;ctsb(+/-) cells, indicating a compensatory function of cathepsin X in CTSB-deficient tumor cells. Finally, an adoptive transfer model, in which ctsb(+/+), ctsb(+/-), and ctsb(-/-) recipient mice were challenged with PyMT;ctsb(+/+) cells, was used to address the role of stroma-derived CTSB in lung metastasis formation. Notably, ctsb(-/-) mice showed reduced number and volume of lung colonies, and infiltrating macrophages showed a strongly up-regulated expression of CTSB within metastatic cell populations. These results indicate that both cancer cell-derived and stroma cell-derived (i.e., macrophages) CTSB plays an important role in tumor progression and metastasis.

Fat suppression in magnetic resonance imaging of the head and neck region: is the two-point DIXON technique superior to spectral fat suppression?

OBJECTIVE: The aim of our study was to systematically compare two-point Dixon fat suppression (FS) and spectral FS techniques in contrast enhanced imaging of the head and neck region. METHODS: Three independent readers analysed coronal T1 weighted images recorded after contrast medium injection with Dixon and spectral FS techniques with regard to FS homogeneity, motion artefacts, lesion contrast, image sharpness and overall image quality. RESULTS: 85 patients were prospectively enrolled in the study. Images generated with Dixon-FS technique were of higher overall image quality and had a more homogenous FS over the whole field of view compared with the standard spectral fat-suppressed images (p < 0.001). Concerning motion artefacts, flow artefacts, lesion contrast and image sharpness no statistically significant difference was observed. CONCLUSION: The Dixon-FS technique is superior to the spectral technique due to improved homogeneity of FS and overall image quality while maintaining lesion contrast. Advances in knowledge: T1 with Dixon FS technique offers, compared to spectral FS, significantly improved FS homogeneity and over all image quality in imaging of the head and neck region.

Usefulness of noninvasive cardiac imaging using dual-source computed tomography in an unselected population with high prevalence of coronary artery disease.

The aim of the present study was to evaluate the diagnostic accuracy of a new dual-source computed tomographic scanner generation with 83-ms temporal resolution in cardiac imaging. Fifty-one unselected consecutive patients (mean age 64 +/- 10 years) scheduled for invasive coronary angiography because of suspected or known coronary artery disease (CAD) were examined with dual-source computed tomography (DSCT). All coronary segments were analyzed regarding the presence of coronary artery lesions. The findings were compared with invasive coronary angiography. During computed tomographic examination, mean heart rate was 65 +/- 14 beats/min. Thirteen of 51 patients (25%) did not have sinus rhythm. Mean Agatston score equivalent was 779 (median 358, range 0 to 3,898). Prevalence of CAD was 75%. Based on a coronary segment model, sensitivity was 96%, specificity 87%, positive predictive value 61%, and negative predictive value 99% for the detection of significant lesions (> or =50% diameter stenosis). The main reason for false-positive results was an overestimation of mild lesions by DSCT. In conclusion, our initial data indicate that DSCT allows a high accuracy to exclude relevant coronary stenosis in unselected patients with a high prevalence of CAD and a relevant number with heart rhythm irregularities. However, overestimation of stenosis, especially in cases of calcifications, is still a limitation.

Influence of a lipid-lowering therapy on calcified and noncalcified coronary plaques monitored by multislice detector computed tomography: results of the New Age II Pilot Study.

PURPOSE: Multislice detector computed tomography (MSCT) is an accurate noninvasive modality to detect and classify different stages of atherosclerosis. The aim of the New Age II Study was to detect coronary lesions in men without established coronary artery disease (CAD) but with a distinct cardiovascular risk profile. We also sought to assess the effect after 1 year of a lipid-lowering therapy (LLT) using 20 mg of atorvastatin. METHODS: Forty-sixe male patients (mean, 61 +/- 10 years) with an elevated risk for CAD (PROCAM score >3 quintile) without LLT were included. Native and contrast-enhanced scans were performed in all patients. A total of 27 of 46 patients received a follow-up scan (after 488 +/- 138 days). Coronary plaque burden (CPB) was assessed volumetrically. RESULTS: The prevalence of CAD was 83% (38/46 patients), and 11% (5/46) without coronary calcifications still had noncalcified plaques. Total cholesterol and low-density lipoprotein cholesterol levels decreased significantly under LLT (225 +/- 41 mg/dL vs. 162 +/- 37 mg/dL, P < 0.0001 and 148 +/- 7 mg/dL vs. 88 +/- 5 mg/dL, P < 0.001, respectively). On follow-up, calcium score and CPB remained unchanged (Agatston score: 261 +/- 301 vs. 282 +/- 360; CPB: 0.149 +/- 0.108 vs. 0.128 +/- 0.075 mL, P > 0.05), whereas mean plaque volume of noncalcified plaques decreased significantly from 0.042 +/- 0.029 mL versus 0.030 +/- 0.014 mL (P < 0.05, mean reduction 0.012 +/- 0.017 mL or 24 +/- 13%). CONCLUSIONS: Statin therapy led to a significant reduction of noncalcified plaque burden that was not reflected in calcium scoring or total plaque burden. This finding might explain the risk reduction after the initiation of statin therapy. Using multislice detector computed tomography, physicians have the potential to monitor medical treatment in patients with coronary atherosclerosis.

Dual-source computed tomography: advances of improved temporal resolution in coronary plaque imaging.

OBJECTIVES: The aim of this study was to quantify image quality gains of a moving coronary plaque phantom using dual-source computed tomography (DSCT) providing 83 milliseconds temporal resolution in direct comparison to 64 slice single-source multidetector CT (MDCT) with a temporal resolution of 165 milliseconds. MATERIALS AND METHODS: Three cardiac vessel phantoms with fixed 50% stenosis and changing plaque configurations were mounted on a moving device simulating cardiac motion. Scans were performed at a simulated heart frequency of 60 to 120 bpm. Image quality assessment was performed in different anatomic orientations inside a thoracic phantom. RESULTS: A significant improvement of image quality using the DSCT could be found (P=0.0002). Relevant factors influencing image quality aside from frequency (P=0.0002) are plaque composition (P<0.0001), as well as orientation (P<0.0001). CONCLUSION: Scanning with 83 milliseconds temporal resolution improved image quality of coronary plaque at higher heart frequencies.

Dual-source CT with improved temporal resolution in assessment of left ventricular function: a pilot study.

OBJECTIVE: Functional analysis using MDCT has been limited by insufficient temporal resolution. The aim of this study was to assess the performance of a dual-source CT system with improved temporal resolution in the determination of both volume- or time-dependent functional parameters and regional wall motion in comparison with cine MRI. SUBJECTS AND METHODS: Twenty patients (15 of whom had previous myocardial infarction) were prospectively examined using dual-source CT. MRI was used as the standard of reference. Using the Simpson's method, ventricular volumes were determined for the whole of the cardiac cycle and results compared using Parson's correlation and Bland-Altman analysis. Regional wall motion was assessed on cine images and compared using weighted kappa statistics. RESULTS: Dual-source CT revealed a strong correlation with cine MRI regarding the quantification of end-diastolic volume (r = 0.98), end-systolic volume (r = 0.99), stroke volume (r = 0.96), and ejection fraction (r = 0.95). Good correlation was obtained for peak ejection rate (r = 0.79) and peak filling rate (r = 0.84), whereas agreement proved only moderate for time-to-peak ejection rate (r = 0.68) or time-to-peak filling rate from end-systole (r = 0.64). The mean difference for ejection fraction was negligible (bias, 0.72%). Good agreement between both techniques was likewise found for regional wall motion (kappa = 0.88). CONCLUSION: With the improvement of temporal resolution between 42 and 83 milliseconds, dual-source CT not only enables accurate assessment of global functional parameters, but it also allows for quantification of time-dependent variables and reliable evaluation of regional wall motion.

Long-term CT follow-up in 40 non-HIV immunocompromised patients with invasive pulmonary aspergillosis: kinetics of CT morphology and correlation with clinical findings and outcome.

OBJECTIVE: The aim of this study was to assess CT signs of invasive pulmonary aspergillosis (IPA) and their long-term kinetics in correlation with clinical findings and outcome. MATERIALS AND METHODS: Three hundred ten serial CT scans (mean, 7.7) in 40 consecutive patients were reviewed retrospectively over a median follow-up of 112 days (range, 5-841 days). Along with underlying disease, hematopoietic stem cell transplantation, neutropenia, graft-versus-host disease or antifungal treatment, signs of IPA, and number or size of lesions were evaluated regarding outcome and radiologic dynamics. RESULTS: On the day of IPA diagnosis, median lesion number and size were 3 or 3.1 cm(2), respectively. Irrespective of antifungal therapy, 90% of patients showed an increase in lesion size and number until day 9 (median and mean). Lesion size subsequently showed a median plateau phase of 3.5 days (mean, 7), during which median lesion numbers dropped by 17%. Consequently, 42.5% of patients showed a complete radiologic remission within a median 80 days. Of all parameters, formation of cavitation most strongly predicted time until radiologic remission, which was 2.5 times as long in patients with cavitary lesions. Likewise, cavitations were strong precursors of beneficial outcome (odds ratio, 8.4; confidence interval [CI], 1.07-176). CONCLUSION: The kinetics of radiologic signs of IPA adheres to a distinctive pattern with initial rise in number and size, followed by a plateau phase of size and gradual reduction. Both time until complete radiologic remission and outcome are independent of initial or maximum lesion size and number yet strongly influenced by cavitation.

Spontaneous thoracic air-leakage syndrome in patients following allogeneic hematopoietic stem cell transplantation: causes, CT-follow up and patient outcome.

OBJECTIVE: The purpose of this article is to describe and illustrate the acute and follow-up imaging features, clinical constellation and outcome of patients with thoracic air-leakage syndrome following allogeneic hematopoietic stem cell transplantation (allo-HCT). METHODS: Patients with evidence of thoracic air-leakage, i.e. spontaneous pneumomediastinum, spontaneous pneumothorax or interstitial emphysema after allo-HCT were retrospectively identified by a chart review. Acute and follow-up morphology, duration and patient outcome were analyzed on CT (HRCT or MSCT with HR-reconstructions). Correlation was made with histological results of transbronchial biopsy. RESULTS: The 6 patients included (3 male and 3 female, 14-64 years old) with thoracic air-leakage after allo-HCT all had histologically proven bronchiolitis obliterans (BO) or bronchiolitis obliterans organizing pneumonia (BOOP). Thoracic air-leakage consisted of spontaneous pneumomediastinum associated with active invasive pulmonary aspergillosis (IPA) in 4/6 and spontaneous pneumothorax or interstitial emphysema each in 1/6 patients. Duration of thoracic air-leakage was 7-135 days. Of the patients with spontaneous pneumomediastinum, 3/4 died of IPA. One patient survived until complete regression of spontaneous pneumomediastinum. One patient died 7 days after spontaneous pneumothorax and one survived developing chronic interstitial emphysema. CONCLUSION: In all cases, thoracic air-leakage was associated to BO or BOOP. In the majority of cases with additional IPA, thoracic air-leakage is more indicative for severity of pulmonary disease than a life-threatening entity itself.