Influence of fractional anisotropy thresholds on diffusion tensor imaging tractography of the periprostatic neurovascular bundle and selected pelvic tissues: do visualized tracts really represent nerves?

Background Diffusion tensor imaging (DTI) tractography has recently been shown to successfully visualize periprostatic tracts allegedly representing the neurovascular bundle. Purpose To examine the impact of different fractional anisotropy (FA) thresholds on the results of DTI tractography in the male pelvis as well as to evaluate the resulting specificity for nerve tracts. Material and Methods Ten healthy male volunteers were examined at 3 Tesla. DTI tractography was performed based on seed points placed circularly around the prostate, in the rectoprostatic angle, the peripheral zone of the prostate, the sciatic nerve, and in addition the urinary bladder using FA thresholds of 0.20, 0.05, and 0.01. DTI tract number and DTI tract length measured with different FA thresholds were compared. ANOVA with repeated measures was used for statistics. Results DTI tract number and tract length were significantly dependent on FA thresholds. While a FA threshold of 0.20 visualized the typical distribution of DTI tracts in the sciatic nerve, a FA threshold of ≤0.05 was necessary to yield results visually mimicking the distribution of nerve tracts in the NVB. However, with such low FA thresholds even in the filled urinary bladder DTI tracts could be visualized. With FA thresholds of 0.20, the number and length of periprostatic DTI tracts did not differ from those measured within the prostate. Conclusion DTI tractography can be used to visualize DTI tracts periprostatically. However, one may doubt that these DTI tracts represent nerve tracts and that the periprostatic neurovascular bundle can be evaluated in a meaningful way with the current methods available.

T2- and diffusion-weighted magnetic resonance imaging at 3T for the detection of prostate cancer with and without endorectal coil: An intraindividual comparison of image quality and diagnostic performance.

OBJECTIVES: To intraindividually compare image quality and diagnostic performance of multiparametric MRI (mpMRI) at 3T for the detection of prostate cancer (PCa) using a pelvic phased-array coil (PAC) and a combined endorectal and pelvic phased-array coil (ERC-PAC). METHODS: Forty-five patients were prospectively included and received mpMRI of the prostate using a PAC and an ERC-PAC during one imaging session. Two radiologists evaluated image quality and the most suspicious lesion according to the PI-RADS scoring system. Results of MRI-TRUS-fusion biopsy of the prostate served as reference standard. Patient comfort and acceptance were assessed using a standardized questionnaire. RESULTS: Overall image quality for T2WI was rated significantly better with an ERC-PAC compared to a PAC (p=0.0038). The weighted kappa for PI-RADS scores for T2WI and DWI with a PAC and an ERC-PAC was 0.70 and 0.73, respectively. For a PI-RADS sum score including T2WI and DWI the area under the curve with a PAC and an ERC-PAC were 0.95-0.99 and 0.93-0.97, respectively (p=0.1395). CONCLUSION: For T2WI and DWI performed at 3T index PCa lesion identification and evaluation did not differ significantly with both coil setups. Patients preferred MRI without an ERC. Therefore, the use of an ERC may be omitted in a prostate cancer detection setting.

A new method of calculating the rotation angle in pediatric forearm fractures using direct radiographs.

BACKGROUND: The aim of this study was to measure the rotational angle defect between fracture ends in paediatric forearm diaphyseal fractures on radiographs. METHODS: Evaluations were performed on 78 paediatric patients who presented at the emergency department with a diaphyseal forearm fracture during 2013-2014. Thirty-two patients who underwent conservative treatment and had < 10° of angulation and translation of not more than half the bone diameter after application of a plaster cast were included in the study. A rotational formula was used with diameter values to determine changes. The degree of rotation of both ends of the fracture line and the forearm rotational defect of the fracture line were calculated. FINDINGS: Fractures included an isolated radius in 16 cases, an isolated ulna in four cases, and both bones in 12 cases. The mean lateral angular (LAT-θ) value was 26.13 ± 5.93° on the proximal fracture end, and the distal mean LAT-θ was 30.29 ± 6.24° (p = 0.037).The mean proximal anteroposterior angular (AP-θ) value was 26.83 ± 5.75°, and the distal mean AP-θ was 30.58 ± 7.27° (p = 0.008). A significant correlation was detected between the AP-Δ and LAT-Δ measurements (p = 0.883). INTERPRETATION: The rotational defect was mathematically calculated directly from radiographs using a rotational measurement formula.

Individual selection of X-ray tube settings in computed tomography coronary angiography: Reliability of an automated software algorithm to maintain constant image quality.

OBJECTIVES: To evaluate a software tool that claims to maintain a constant contrast-to-noise ratio (CNR) in high-pitch dual-source computed tomography coronary angiography (CTCA) by automatically selecting both X-ray tube voltage and current. METHODS: A total of 302 patients (171 males; age 61±12years; body weight 82±17kg, body mass index 27.3±4.6kg/cm(2)) underwent CTCA with a topogram-based, automatic selection of both tube voltage and current using dedicated software with quality reference values of 100kV and 250mAs/rotation (i.e., standard values for an average adult weighing 75kg) and an injected iodine load of 222mg/kg. RESULTS: The average radiation dose was estimated to be 1.02±0.64mSv. All data sets had adequate contrast enhancement. Average CNR in the aortic root, left ventricle, and left and right coronary artery was 15.7±4.5, 8.3±2.9, 16.1±4.3 and 15.3±3.9 respectively. Individual CNR values were independent of patients' body size and radiation dose. However, individual CNR values may vary considerably between subjects as reflected by interquartile ranges of 12.6-18.6, 6.2-9.9, 12.8-18.9 and 12.5-17.9 respectively. Moreover, average CNR values were significantly lower in males than females (15.1±4.1 vs. 16.6±11.7 and 7.9±2.7 vs. 8.9±3.0, 15.5±3.9 vs. 16.9±4.6 and 14.7±3.6 vs. 16.0±4.1 respectively). CONCLUSION: A topogram-based automatic selection of X-ray tube settings in CTCA provides diagnostic image quality independent of patients' body size. Nevertheless, considerable variation of individual CNR values between patients and significant differences of CNR values between males and females occur which questions the reliability of this approach.

The value of ADC, T2 signal intensity, and a combination of both parameters to assess Gleason score and primary Gleason grades in patients with known prostate cancer.

BACKGROUND: The ability to non-invasively analyze tumor aggressiveness is an important predictor for individual treatment stratification and patient outcome in prostate cancer (PCA). PURPOSE: To evaluate: (i) whether apparent diffusion coefficient (ADC), the T2 signal intensity (SI), and a combination of both parameters allow for an improved discrimination of Gleason Score (GS) ≥7 (intermediate and high risk) and GS <7 (low risk) in PCA; and (ii) whether ADC may distinguish between 3 + 4 and 4 + 3 PCA (primary Gleason grades [pGG]). MATERIAL AND METHODS: Prostatectomy specimens of 66 patients (mean age, 63 ± 5.6 years; 104 PCA foci) with a preceding multiparametric 1.5 T endorectal coil magnetic resonance imaging (MRI) were included. ADC (b values = 0, 100, 400, 800 s/mm(2)), standardized T2 (T2s), and the ADC/T2s ratio were tested for correlation with GS applying multivariate analysis. ADC cutoff values were calculated for prediction of GS and pGG, and logarithm of the odds (LOGIT) was used to express the probability for GS and pGG. Diagnostic accuracy was assessed by ROC analysis. RESULTS: We found an almost linear negative relationship of ADC for GS ≥7 (P = 0.002). The effect of ADC for GS ≥7 (adjusted odds ratio = 0.995) was almost identical for peripheral and transition zone PCA (P = 0.013 and P < 0.001, respectively). ADC showed an AUC of 78.9% for discrimination between GS <7 and GS ≥7. An ADC cutoff of <1.005 × 10(-3 )mm(2)/s indicated a GS ≥7 (90.5% sensitivity, 62.5% specificity). Within the group of GS = 7 PCA, an ADC > 0.762 × 10(-3 )mm(2)/s indicated a pGG of 3 (AUC = 69.6%). CONCLUSION: T2s and the ADC/T2s ratio do not provide additional information regarding prediction of GS. ADC values have a good discriminatory power to distinguish tumors with GS ≥7 from GS <7 and to predict pGG in GS = 7 PCA.

The detection of significant prostate cancer is correlated with the Prostate Imaging Reporting and Data System (PI-RADS) in MRI/transrectal ultrasound fusion biopsy.

PURPOSE: To evaluate the performance of real-time MRI/ultrasound (MRI/US) fusion-guided targeted biopsy (TB) in men with primary and repeat biopsies and correlate the prostate cancer detection rate (CDR) with the PI-RADS score. METHODS: Analysis included 408 consecutive men with primary and prior negative biopsies who underwent TB and 10-core random biopsy (RB) between January 2012 and January 2015. TB was performed with a real-time MRI/US fusion platform with sensor-based registration. Clinically significant PCa was defined as Gleason score (GS) ≥ 7 or GS 6 with maximal cancer core length ≥ 4 mm for TB and according to Epstein criteria for RB. RESULTS: The overall CDR was 56 % (227/408). The CDR for primary biopsy was 74 % (60/81) and 57 % (67/117), 49 % (62/126), 45 % (38/84) for patients with 1, 2 and ≥ 3 prior negative biopsies. CDRs correlated with PI-RADS 2/3/4/5 were 16 % (5/32), 26 % (29/113), 62 % (94/152) and 89 % (99/111), respectively. The rates of significant tumors in relation to PI-RADS 2/3/4/5 were 60 % (3/5), 66 % (19/29), 74 % (70/94), 95 % (94/99). In 139 (61 %) cases with radical prostatectomy (RP), the rates of ≥ pT3 tumors in correlation with PI-RADS 4 and 5 were 20 % (11/56) and 49 % (32/65). PI-RADS constituted the strongest predictor of significant PCa detection (p < 0.007). CONCLUSIONS: Real-time MRI/US fusion-guided TB combined with RB improved PCa detection in patients with primary and repeat biopsies. The CDR was strongly correlated with a rising PI-RADS score, values of 4 and 5 increasing the detection of clinically significant tumors and leading to a higher histological stage after RP.

Prostate cancer detection on transrectal ultrasonography-guided random biopsy despite negative real-time magnetic resonance imaging/ultrasonography fusion-guided targeted biopsy: reasons for targeted biopsy failure.

OBJECTIVE: To examine the value of additional transrectal ultrasonography (TRUS)-guided random biopsy (RB) in patients with negative magnetic resonance imaging (MRI)/ultrasonography (US) fusion-guided targeted biopsy (TB) and to identify possible reasons for TB failure. PATIENTS AND METHODS: We conducted a subgroup analysis of 61 men with prostate cancer (PCa) detected by 10-core RB but with a negative TB, from a cohort of 408 men with suspicious multiparametric magnetic resonance imaging (mpMRI) between January 2012 and January 2015. A consensus re-reading of mpMRI results (using Prostate Imaging Reporting and Data System [PI-RADS] versions 1 and 2) for each suspicious lesion was performed, with the image reader blinded to the biopsy results, followed by an unblinded anatomical correlation of the lesion on mpMRI to the biopsy result. The potential reasons for TB failure were estimated for each lesion. We defined clinically significant PCa according to the Epstein criteria and stratified patients into risk groups according to the European Association of Urology guidelines. RESULTS: Our analysis showed that RB detected significant PCa in 64% of patients (39/61) and intermediate-/high-risk PCa in 57% of patients (35/61). The initial mpMRI reading identified 90 suspicious lesions in the cohort. Blinded consensus re-reading of the mpMRI led to PI-RADS score downgrading of 45 lesions (50%) and upgrading of 13 lesions (14%); thus, negative TB could be explained by falsely high initial PI-RADS scores for 32 lesions (34%) and sampling of the target lesion by RB in the corresponding anatomical site for 36 out of 90 lesions (40%) in 35 of 61 patients (57%). Sampling of the target lesion by RB was most likely for lesions with PI-RADS scores of 4/5 and Gleason scores (GS) of ≥7. A total of 70 PCa lesions (67% with GS 6) in 44 patients (72%) were sampled from prostatic sites with no abnormalities on mpMRI. CONCLUSION: In cases of TB failure, RB still detected a high rate of significant PCa. The main reason for a negative TB was a TB error, compensated for by positive sampling of the target lesion by the additional RB, and the second reason for TB failure was a falsely high initial PI-RADS score. The challenges that arise for both MRI diagnostics and prostate lesion sampling are evident in our data and support the integration of RB into the TB workflow.

Low Dose Computed Tomography for 3D Planning of Total Hip Arthroplasty: Evaluation of Radiation Exposure and Image Quality.

OBJECTIVE: The aim of the study was to compare radiation exposure and image quality between dedicated computed tomography (CT) protocols for preoperative total hip arthroplasty (THA) planning. METHODS: Three protocols with automated tube current modulation using 64-slice (n = 177) and 128-slice CT scanners without (n = 129) and with automated tube voltage preselection (n = 84) were compared. RESULTS: All 390 CTs were of sufficient quality for THA planning. Mean DLP was 235.0 mGy*cm (effective dose 2.8 mSv). Lowest radiation exposure (2.5 mSv) was seen with automated voltage preselection and the algorithm's selection was 100 kV (90.5% of patients) and 120 kV. Lowest image noise was seen in the highest dose group (3.1 mSv, 128-slice CT fixed tube voltage). A significant difference in cortical bone radiodensity was seen between 100 kV and 120 kV (P < 0.0001). CONCLUSIONS: Preoperative pelvic CT for THA planning is possible with very low radiation dose and reliable quality. Automated voltage preselection further decreases the effective dose by 18.2%.

Added Value of Multiparametric Ultrasonography in Magnetic Resonance Imaging and Ultrasonography Fusion-guided Biopsy of the Prostate in Patients With Suspicion for Prostate Cancer.

OBJECTIVE: To analyze whether magnetic resonance imaging-ultrasonography (MRI-US) fusion-guided biopsy detects more and clinical significant prostate cancer (PCa) in comparison to conventional transrectal US-guided prostate biopsy (PBX) and to investigate if multiparametric (mp) US during MRI-US fusion can further characterize mpMRI-suspected lesions according to the prostate MRI reporting and data system (PI-RADS). METHODS: From January 2012 to January 2014, 169 patients with a median of 2 negative conventional PBX and/or initially or consistently elevated prostate-specific antigen levels were prospectively included and underwent 3 T mpMRI. Real-time MRI-US fusion scan was used to biopsy the mpMRI-targeted lesions (n = 316). Scanning by mpUS, including B-mode, power Doppler, strain elastography, and contrast-enhanced US was performed to further characterize those lesions and to score by US modalities resulting in an mpUS score. Afterward, a conventional 10-core PBX was performed. PCa detection based on the results of targeted and conventional PBX was estimated. Performances of single US modalities were analyzed. The mpUS score was also investigated for PCa and PI-RADS score prediction. RESULTS: Among 169 patients, 71 PCa (42%) were detected. From these 71 cases, clinically significant PCa (Gleason score ≥7) were detected exclusively by MRI-US fusion in 31 from 46 cases (67.4%). The highest sensitivity was observed in contrast-enhanced US (85%) and elastography (80%). The mpUS score predicts PCa and PI-RADS score with an overall accuracy of 86% and 80%, respectively. CONCLUSION: MRI-US fusion-guided PBX detects more clinically significant PCa compared with conventional TRUS. The mpUS score correlates with PI-RADS in PCa prediction.

Inflammatory myofibroblastic tumor of the liver mimicking an infiltrative malignancy in computed tomography and magnetic resonance imaging with Gd-EOB.

Inflammatory myofibroblastic tumors (IMT) are a benign tumor entity, which rarely develop in the liver. Surgery is the most common treatment for these lesions as it is difficult to distinguish them from malignant liver tumors and local recurrent growth may occur. IMT is a diagnostic challenge for imaging. Only a limited number of reports of single cases or small number of patients described the imaging features on computed tomography. Reports on IMT appearance on magnetic resonance imaging are scarce. We present a case of IMT of the liver with infiltration of the abdominal wall treated with surgery and describe the imaging features with the use of the hepatobiliary contrast agent, gadoxetic acid (Gd-EOB).

Myosin IXb variants and their pivotal role in maintaining the intestinal barrier: a study in Crohn's disease.

BACKGROUND: Myosin IXb (MYO9B) is involved in the regulation of epithelial barrier function. We hypothesized that MYO9B variants are associated with increased intestinal permeability measured in patients with Crohn's disease (CD), where barrier dysfunction is crucially involved in disease development. METHODS: We sequenced MYO9B and genotyped five MYO9B variants (rs1545620, rs1457092, rs2279003, rs2305764 and rs2279002) and correlated these data to measurement of intestinal permeability in German CD patients (n = 122) obtained by standard oral sugar test using the lactulose/mannitol ratio after measurement of urinary excretion. We furthermore studied MYO9B variants in three European cohorts with inflammatory bowel disease (IBD) and healthy controls : Germany (CD = 264; ulcerative colitis = 143 [UC]; HC = 372); Hungary (CD = 147; UC = 117; HC = 195), the Netherlands (CD = 157; HC = 219). RESULTS: We found an association for four studied MYO9B variants to an increased intestinal permeability in CD patients (rs1545620, p = 0.010; rs1457092, p = 0.024; rs2279003, p = 0.003; rs2305764, p = 0.015). Furthermore, we observed significantly higher absolute values of intestinal permeability for individuals carrying risk alleles within MYO9B. Looking for an overall disease association, only the rs2305764 variant was associated with CD in the Dutch cohort (p = 0.004), but not in the German or Hungarian cohort. No association to UC or a distinct phenotype in both CD and UC patients was observed for all studied MYO9B variants. CONCLUSION: Our data suggest a link between MYO9B variants to an increased intestinal permeability in CD patients. This supports the influence of Myosin IXb on the integrity of the epithelial barrier. The role of MYO9B variants in the overall susceptibility to IBD, however, remains to be elucidated.

Comparison of gadoteric acid and gadobutrol for detection as well as morphologic and dynamic characterization of lesions on breast dynamic contrast-enhanced magnetic resonance imaging.

OBJECTIVE: In contrast to conventional breast imaging techniques, one major diagnostic benefit of breast magnetic resonance imaging (MRI) is the simultaneous acquisition of morphologic and dynamic enhancement characteristics, which are based on angiogenesis and therefore provide insights into tumor pathophysiology. The aim of this investigation was to intraindividually compare 2 macrocyclic MRI contrast agents, with low risk for nephrogenic systemic fibrosis, in the morphologic and dynamic characterization of histologically verified mass breast lesions, analyzed by blinded human evaluation and a fully automatic computer-assisted diagnosis (CAD) technique. MATERIALS AND METHODS: Institutional review board approval and patient informed consent were obtained. In this prospective, single-center study, 45 women with 51 histopathologically verified (41 malignant, 10 benign) mass lesions underwent 2 identical examinations at 1.5 T (mean time interval, 2.1 days) with 0.1-mmol kg doses of gadoteric acid and gadobutrol. All magnetic resonance images were visually evaluated by 2 experienced, blinded breast radiologists in consensus and by an automatic CAD system, whereas the morphologic and dynamic characterization as well as the final human classification of lesions were performed based on the categories of the Breast imaging reporting and data system MRI atlas. Lesions were also classified by defining their probability of malignancy (morpho-dynamic index; 0%-100%) by the CAD system. Imaging results were correlated with histopathology as gold standard. RESULTS: The CAD system coded 49 of 51 lesions with gadoteric acid and gadobutrol (detection rate, 96.1%); initial signal increase was significantly higher for gadobutrol than for gadoteric acid for all and the malignant coded lesions (P < 0.05). Gadoteric acid resulted in more postinitial washout curves and fewer continuous increases of all and the malignant lesions compared with gadobutrol (CAD hot spot regions, P < 0.05). Morphologically, the margins of the malignancies were different between the 2 agents, whereas gadobutrol demonstrated more spiculated and fewer smooth margins (P < 0.05). Lesion classifications by the human observers and by the morpho-dynamic index compared with the histopathologic results did not significantly differ between gadoteric acid and gadobutrol. CONCLUSIONS: Macrocyclic contrast media can be reliably used for breast dynamic contrast-enhanced MRI. However, gadoteric acid and gadobutrol differed in some dynamic and morphologic characterization of histologically verified breast lesions in an intraindividual, comparison. Besides the standardization of technical parameters and imaging evaluation of breast MRI, the standardization of the applied contrast medium seems to be important to receive best comparable MRI interpretation.

Evaluation of the prostate imaging reporting and data system for the detection of prostate cancer by the results of targeted biopsy of the prostate.

PURPOSE: The purpose of this study was to evaluate the magnetic resonance prostate imaging reporting and data system (PI-RADS) for the detection of prostate cancer by the results of magnetic resonance imaging (MRI)-guided biopsy of the prostate as a reference standard. PATIENTS AND METHODS: In 55 patients who had undergone MRI-guided biopsy of the prostate, we retrospectively matched every biopsy core with the corresponding lesion in previously acquired endorectal multiparametric MRI including T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and dynamic contrast-enhanced MRI (DCE-MRI) at 1.5 T. Two readers blinded to the results of the biopsy evaluated each biopsied lesion according to the PI-RADS scoring system. The results of the targeted biopsy were used as a reference standard. Receiver operating characteristic analysis was performed for statistical analysis. RESULTS: A total of 113 lesions in the 55 patients were evaluated; 30 lesions were malignant. When evaluated according to the criteria of the PI-RADS scoring system, DCE-MRI revealed a lower area under the receiver operating characteristic curve (AUC) (0.76) compared with T2WI (0.88; P=0.06) and DWI (0.93; P=0.004). A sum score combining T2WI, DWI, and DCE-MRI yielded an AUC of 0.93, whereas a sum score combining only T2WI and DWI yielded an AUC of 0.95. In central gland lesions, T2WI showed a numerically higher AUC compared with DWI (0.98 and 0.95), whereas, in peripheral zone lesions, DWI was superior (AUC of 0.93 and 0.73; P=0.04). An approach assigning a PI-RADS score for T2WI to central gland lesions and for DWI to peripheral zone lesions yielded an AUC of 0.96 and was numerically superior compared with any sequence alone and sum scores combining T2WI and DWI as well as T2WI, DWI, and DCE-MRI. CONCLUSIONS: The PI-RADS scoring system shows a good diagnostic performance for the detection of prostate cancer when using a sum score. However, DCE-MRI does not seem to add significant value when evaluated according to the recommended criteria. Assigning a score for T2WI to central gland lesions and for DWI to peripheral zone lesions might be sufficient for stratification of patients for further diagnostic workup.

Intraindividual comparison of T1 relaxation times after gadobutrol and Gd-DTPA administration for cardiac late enhancement imaging.

PURPOSE: To evaluate T1-relaxation times of chronic myocardial infarction (CMI) using gadobutrol and gadopentetate dimeglumine (Gd-DTPA) over time and to determine the optimal imaging window for late enhancement imaging with both contrast agents. MATERIAL AND METHODS: Twelve patients with CMI were prospectively included and examined on a 1.5 T magnetic resonance (MR) system using relaxivity-adjusted doses of gadobutrol (0.15 mmol/kg) and Gd-DTPA (0.2 mmol/kg) in random order. T1-relaxation times of remote myocardium (RM), infarcted myocardium (IM), and left ventricular cavity (LVC) were assessed from short-axis TI scout imaging using the Look-Locker approach and compared intraindividually using a Wilcoxon paired signed-rank test (α<0.05). RESULTS: Within 3 min of contrast agent administration (CA), IM showed significantly lower T1-relaxation times than RM with both contrast agents, indicating beginning cardiac late enhancement. Differences between gadobutrol and Gd-DTPA in T1-relaxation times of IM and RM were statistically not significant through all time points. However, gadobutrol led to significantly higher T1-relaxation times of LVC than Gd-DTPA from 6 to 9 min (220 ± 15 ms vs. 195 ± 30 ms p<0.01) onwards, resulting in a significantly greater ΔT1 of IM to LVC at 9-12 min (-20 ± 35 ms vs. 0 ± 35 ms, p<0.05) and 12-15 min (-25 ± 45 ms vs. -10 ± 60 ms, p<0.05). Using Gd-DTPA, comparable ΔT1 values were reached only after 25-35 min. CONCLUSION: This study indicates good delineation of IM to RM with both contrast agents as early as 3 min after administration. However, we found significant differences in T1 relaxation times with greater ΔT1 IM-LVC using 0.15 mmol/kg gadobutrol compared to 0.20 mmol/kg Gd-DTPA after 9-15 min post-CA suggesting earlier differentiability of IM and LVC using gadobutrol.

High-pitch dual-source CT coronary angiography with low volumes of contrast medium.

OBJECTIVES: To assess the effect of lower volumes of contrast medium (CM) on image quality in high-pitch dual-source computed tomography coronary angiography (CTCA). METHODS: One-hundred consecutive patients (body weight 65-85 kg, stable heart rate ≤65 bpm, cardiac index ≥2.5 L/min/m(2)) referred for CTCA were prospectively enrolled. Patients were randomly assigned to one of five groups of different CM volumes (G30, 30 mL; G40, 40 mL; G50, 50 mL; G60, 60 mL; G70, 70 mL; flow rate 5 mL/s each, iodine content 370 mg/mL). Attenuation within the proximal and distal coronary artery segments was analysed. RESULTS: Mean attenuation for men and women ranged from 345.0 and 399.1 HU in G30 to 478.2 and 571.8 HU in G70. Mean attenuation values were higher in groups with higher CM volumes (P < 0.0001) and higher in women than in men (P < 0.0001). The proportions of segments with attenuation of at least 300 HU in G30, G40, G50, G60 and G70 were 89 %, 95 %, 98 %, 98 % and 99 %. CM volume of 30 mL in women and 40 mL in men proved to be sufficient to guarantee attenuation of at least 300 HU. CONCLUSIONS: In selected patients high-pitch dual-source CTCA can be performed with CM volumes of 40 mL in men or 30 mL in women. KEY POINTS: • High-pitch dual-source coronary angiography is feasible with low contrast media volumes. • Traditional injection rules still apply: higher volumes result in higher enhancement. • The patient's gender is a co-factor determining the level of contrast enhancement. • Volumes can be reduced down to 30-40 mL in selected patients.

Galectin-3 increase in endurance athletes.

BACKGROUND: Galectin-3 is a new and promising biomarker for heart failure and myocardial fibrosis. Although endurance exercise is a crucial element in cardiovascular disease prevention, the relationship between exercise and plasma levels of galectin-3 is still unknown. To date, the relationship between regular exercise and myocardial fibrosis is not fully understood. This study investigates the relationship between endurance exercise and plasma levels of galectin-3. METHODS: Twenty-one male, healthy non-elite marathon runners were examined before and within 1 hour after a strenuous run of 30 km after 4-day training abstinence. Examination included blood samples for galectin-3, echocardiography, and cardiac magnetic resonance imaging (CMR). In addition, to distinguish between cardiac or skeletal muscular origin of galectin-3, 27 C57Bl/6 J mice performing voluntary wheel running and 25 sedentary mice were analysed. RESULTS: Plasma galectin-3 in endurance athletes increased from baseline to post exercise (12.8 ± 3.4 ng/ml to 19.9 ± 3.9 ng/ml, p < 0.001) while the systolic left and right ventricular function remained unchanged. Interestingly, baseline plasma levels of galectin-3 were in normal range but higher than in healthy sedentary controls. However, in CMR there was no correlation between baseline galectin-3 levels and the detection of myocardial fibrosis. In animal studies, the relative level of mRNA for galectin-3 in active mice was significantly higher compared to sedentary mice. This increase was most pronounced in skeletal muscle (98.0% higher, p < 0.001) and not in the myocardium of the left ventricle (19.9% higher, p = 0.043). CONCLUSIONS: Plasma galectin-3 is substantially elevated in endurance athletes after running but does not correlate with cardiac function, other biomarkers, or myocardial fibrosis. In mice, we demonstrate that galectin-3 increase during endurance exercise originates primarily from skeletal muscle.

MR-guided biopsy of the prostate: comparison of diagnostic specimen quality with 18 G and 16 G biopsy needles.

PURPOSE: To evaluate specimen quality and diagnostic differences between magnetic resonance (MR) compatible 16 G and 18 G biopsy needles in MR-guided biopsy (MRGB) of the prostate. MATERIALS AND METHODS: Semiautomatic MR compatible biopsy needles with a diameter of 16 G (Group A) or 18 G (Group B) were used to perform MRGB in 88 patients with suspected prostate cancer. After embedding and staining, length and width of all specimens (140 cores in Group A, 143 in Group B) were measured. Fragmentation, squeezing artifacts, and overall evaluability were evaluated using a quality score from 0 (no tissue) to 3 (optimal tissue quality). Groups were statistically compared; p-values <0.05 were regarded as significant. RESULTS: Demographic data were not significantly different between Group A and B with a mean age of 63 ± 7.3 and 67 ± 5.7 years; and a mean prostate-specific antigen of 12.6 ± 10.3 ng/ml and 13.8 ± 11.6 ng/ml, respectively (p=0.70). Area of longitudinally sectioned histological specimens was significantly larger in Group A than in Group B with 9.38 mm(2) (8.74; 10.02) and 7.95 mm(2) (7.32; 8.59), respectively (p=0.002). However, there were significantly more cores without prostate tissue with 18 cores (12.9%) versus 3 cores (2.1%) in Groups A and B, respectively (p=0.004). Fragmentation, squeezing artifacts, and overall evaluability were not statistically different between the two groups. The rate of prostate cancer in the cores was also not significantly different between Groups A and B (22.1% and 24.5%; p=0.77). CONCLUSION: 16 G biopsy needles do not provide a relevant diagnostic advantage over 18 G needles in MRGB. Therefore, use of 18 G needles is not discouraged and may even be preferred as it is not expected to result in a relevant degradation of specimen quality or compromise in prostate cancer detection rate.

MRI-guided biopsy of the prostate: correlation between the cancer detection rate and the number of previous negative TRUS biopsies.

PURPOSE: We aimed to investigate prostate cancer detection rate of magnetic resonance imaging (MRI)-guided biopsy and to elucidate possible relations to the number of prior negative transrectal ultrasonography (TRUS)-guided biopsies. MATERIALS AND METHODS: Eighty-seven consecutive patients (mean age, 65.0 years; mean prostate-specific antigen, 13.3 ng/mL) with at least one prior negative TRUS-guided biopsy and persistent suspicion of prostate cancer were included in this study. All patients underwent MRI-guided biopsy after a diagnostic multiparametric MRI examination at 1.5 Tesla. Specimens were immediately fixated and subsequently evaluated by an experienced uropathologist. Prostate cancer detection rates were calculated. Prostate cancer-positive and -negative cores were compared. Correlation between number of prior biopsies and presence of prostate cancer was evaluated. RESULTS: Cancer detection rates for patients with one (n=24), two (n=25), three (n=18), and four or more (n=20) negative TRUS-guided biopsies were 29.2%, 40.0%, 66.7%, and 35.0%, respectively (P = 0.087). The median number of removed cores per patient was 3 (range, 1-8) without a significant difference between patients with and without cancer (P = 0.48). Thirty of 36 cancer patients were at intermediate or high risk according to the D´Amico clinical risk score. Eleven of 15 high risk cancers were localized in the transition zone (P = 0.002). CONCLUSIONS: This study demonstrates high cancer detection rates of MRI-guided biopsy independent of the number of previous TRUS-guided biopsies and the number of taken prostate cores. MRI-guided biopsy therefore represents a less invasive and effective diagnostic tool for patients with prostate cancer suspicion and previous negative TRUS-guided biopsies.

Salmonella SL7207 application is the most effective DNA vaccine delivery method for successful tumor eradication in a murine model for neuroblastoma.

Attenuated Salmonella is an approved oral life vaccine that is currently entering pre-clinical cancer vaccination studies as a promising DNA carrier. In a syngeneic mouse model for neuroblastoma, oral gavage of Salmonella typhimurium (SL7207) carrying recent generated survivin DNA vaccines induced a stronger cellular anti-NB immune response than gene gun application or injection of lentivirally transduced bone marrow-derived DCs. The level of Salmonella-associated side effects was not significant as indicated by unaffected survivin-mediated hematopoiesis and wound healing. We believe that our findings provide an important baseline to translate Salmonella-based DNA vaccination into a clinical application for neuroblastoma.

Macrocyclic contrast agents for magnetic resonance imaging of chronic myocardial infarction: intraindividual comparison of gadobutrol and gadoterate meglumine.

OBJECTIVES: To compare 0.15 mmol/kg gadobutrol for late gadolinium enhancement (LGE) imaging of chronic myocardial infarction with a relaxivity-adjusted dose of gadoterate meglumine (Gd-DOTA). METHODS: Seventeen patients with suspected chronic myocardial infarction underwent LGE imaging at 1.5 T, acquiring an inversion-recovery-prepared gradient echo sequence 15 min after contrast agent administration. Each patient underwent LGE imaging twice, once after administration of 0.15 mmol/kg gadobutrol (r1 = 5.2 l mmol(-1) s(-1)) and after 0.22 mmol/kg Gd-DOTA (r1 = 3.6 l mmol(-1) s(-1)). Two readers independently determined infarct size and contrast-to-noise ratios of infarcted myocardium to remote myocardium (CNR(remote)) and to the left ventricular lumen (CNR(lumen)). RESULTS: LGE was present in 14 patients. Infarct sizes determined after administration of gadobutrol [23.4 ml; 95 % CI (14.4; 32.5)] and Gd-DOTA [22.1 ml; 95 % CI (13.0; 31.1)] were not statistically different (P = 0.22). The CNR(remote) of LGE in infarcted myocardium on gadobutrol- and Gd-DOTA-enhanced images was 44.1 [95 % CI (31.0; 57.1)] and 45.2 [95 % CI (32.2; 58.3)], respectively (P = 0.73). CNR(lumen) was significantly higher on gadobutrol-enhanced LGE images [12.7; 95 % CI (2.5; 23.0) versus 6.8; 95 % CI (-3.5; 17.0); P = 0.02]. CONCLUSION: At relaxivity-adjusted doses, gadobutrol and Gd-DOTA yielded similar infarct sizes with superior contrast between infarcted myocardium and left ventricular lumen on gadobutrol-enhanced images.