Does gadoxetate disodium affect MRE measurements in the delayed hepatobiliary phase?

OBJECTIVES: To assess if the administration of gadoxetate disodium (Gd-EOB-DTPA) significantly affects hepatic magnetic resonance elastography (MRE) measurements in the delayed hepatobiliary phase (DHBP). METHODS: A total of 47 patients (15 females, 32 males; age range 23-78 years, mean 54.28 years) were assigned to standard hepatic magnetic resonance imaging (MRI) with application of Gd-EOB-DTPA and hepatic MRE. MRE was performed before injection of Gd-EOB-DTPA and after 40-50 min in the DHBP. Liver stiffness values were obtained before and after contrast media application and differences between pre- and post-Gd-EOB-DTPA values were evaluated using a Bland-Altman plot and the Mann-Whitney-Wilcoxon test. In addition, the data were compared with regard to the resulting fibrosis classification. RESULTS: Mean hepatic stiffness for pre-Gd-EOB-DTPA measurements was 4.01 kPa and post-Gd-EOB-DTPA measurements yielded 3.95 kPa. We found a highly significant individual correlation between pre- and post-Gd-EOB-DTPA stiffness values (Pearson correlation coefficient of r = 0.95 (p < 0.001) with no significant difference between the two measurements (p =0.49)). Bland-Altman plot did not show a systematic effect for the difference between pre- and post-stiffness measurements (mean difference: 0.06 kPa, SD 0.81). Regarding the classification of fibrosis stages, the overall agreement was 87.23% and the intraclass correlation coefficient was 96.4%, indicating excellent agreement. CONCLUSIONS: Administration of Gd-EOB-DTPA does not significantly influence MRE stiffness measurements of the liver in the DHBP. Therefore, MRE can be performed in the DHBP. KEY POINTS: • MRE of the liver can reliably be performed in the delayed hepatobiliary phase. • Gd-EOB-DTPA does not significantly influence MRE stiffness measurements of the liver. • MRE performed in the delayed hepatobiliary-phase is reasonable in patients with reduced liver function.

Selective-versus-Standard Poststent Dilation for Carotid Artery Disease: A Systematic Review and Meta-Analysis.

BACKROUND: The safety and efficacy of standard poststent angioplasty in patients undergoing carotid artery stent placement have not been well-established. PURPOSE: We conducted a systematic review of the literature to evaluate the safety and efficacy of carotid artery stent placement and analyzed outcomes of standard-versus-selective poststent angioplasty. DATA SOURCES: A systematic search of MEDLINE, EMBASE, Scopus, and the Web of Science was performed for studies published between January 2000 and January 2015. STUDY SELECTION: We included studies with >30 patients describing standard or selective poststent angioplasty during carotid artery stent placement. DATA ANALYSIS: A random-effects meta-analysis was used to pool the following outcomes: periprocedural stroke/TIA, procedure-related neurologic/cardiovascular morbidity/mortality, bradycardia/hypotension, long-term stroke at last follow-up, long-term primary patency, and technical success. DATA SYNTHESIS: We included 87 studies with 19,684 patients with 20,378 carotid artery stenoses. There was no difference in clinical (P = .49) or angiographic outcomes (P = .93) in carotid artery stent placement treatment with selective or standard poststent balloon angioplasty. Both selective and standard poststent angioplasty groups had a very high technical success of >98% and a low procedure-related mortality of 0.9%. There were no significant differences between both groups in the incidence of restenosis (P = .93) or procedure-related complications (P = .37). LIMITATIONS: No comparison to a patient group without poststent dilation could be performed. CONCLUSIONS: Our meta-analysis demonstrated no significant difference in angiographic and clinical outcomes among series that performed standard poststent angioplasty and those that performed poststent angioplasty in only select patients.

[Knotted Seldinger wire]. / Verknoteter Seldinger-Draht.

Central venous catheters are usually positioned using the Seldinger technique with a guidewire. This article reports a case where the guidewire was inserted via the left subclavian vein with the landmark technique. The guidewire became kinked, pierced the vessel wall and became stuck forming several loops within the adjacent tissue of the vein. Several attempts were made to remove the guidewire by interventional radiology but were unsuccessful. Due to the critical condition of the patient an operation was considered too perilous and the guidewire was finally left in situ. No formation of local venous thrombosis could be detected.

Residual Thromboembolic Material in Cerebral Arteries after Endovascular Stroke Therapy Can Be Identified by Dual-Energy CT.

BACKGROUND AND PURPOSE: Dual-energy CT features the opportunity to differentiate among up to 3 different materials because the absorption of x-rays depends on the applied tube voltage and the atomic number of the material. For example, it is possible to distinguish between blood-brain barrier disruption and an intracerebral hemorrhage following treatment for a stroke. The aim of this study was to evaluate whether dual-energy CT is capable of distinguishing intra-arterial contrast agent from residually clotted vessels immediately after endovascular stroke therapy. MATERIALS AND METHODS: Sixteen patients (9 women, 7 men; mean age, 63.6 ± 13.09 years) were examined. Measurements were made on the postinterventional dual-energy CT virtual noncontrast, iodine map, and "weighted" brain window (weighted dual-energy) series. Postinterventional conventional angiography was used as the criterion standard method. RESULTS: A residual clot was found in 10 patients. On the virtual noncontrast series, the Hounsfield attenuation of the clotted arteries was higher than that in the corresponding perfused contralateral arteries (53.72 ± 9.42 HU versus 41.64 ± 7.87 HU; P < .05). The latter had higher absorption values on the weighted dual-energy series than on the virtual noncontrast series (49.37 ± 7.44 HU versus 41.64 ± 7.87 HU; P < .05). The sensitivity for the detection of a residual clot was 90%; the specificity was 83.3%, and the accuracy was 87.5%. Interrater agreement was good (κ = 0.733). CONCLUSIONS: Dual-energy CT may be valuable in the detection of clot persistence or early re-thrombosis without the necessity of additional contrast administration. However, its relevance for the prediction of outcomes remains to be determined in further studies.

[Arterial Access Site Complications after Percutaneous Interventions with Special Regard to the Application of Vascular Closure Devices]. / Arterielle Zugangswegkomplikationen nach perkutanen Interventionen unter besonderer Berücksichtigung der Verwendung von Verschlusssystemen.

Due to an increase in the number of performed endovascular procedures, the number of local access site complications is rising too. Used mainly for treatment of peripheral arterial disease and coronary heart disease, endovascular procedures are gaining importance. Access site complications include bleeding, haematoma, pseudoaneurysm, arteriovenous fistula and arterial thrombosis. Aiming to reduce immobilisation, length of hospital stay, costs and access site complications, vascular closure devices (VCD) were introduced in the mid 1990s, but current trials failed to demonstrate the superiority of these devices compared to conventional manual compression if it comes to access site complications. We retrospectively evaluated all patients who were treated surgically due to access site complications between 2001 and 2012 in our institution. In total, 522 patients needed vascular surgery to treat different access site complications. During this period, 90,538 percutaneous interventions were performed in our institution, leading to a total incidence of 0.58 % of access site complications. Depending on the frequency of application of VCDs, patients have been grouped in groups A-C. With the more frequent use of VCDs, the incidence of access site complications increased and, in particular, ischaemic complications were seen more often. In conclusion, the application of VCDs to prevent access site complications is questionable and not justified when looking at published data.

A new radiological method to detect dorsally penetrating screws when using volar locking plates in distal radial fractures. The dorsal horizon view.

Penetration of the dorsal screw when treating distal radius fractures with volar locking plates is an avoidable complication that causes lesions of the extensor tendon in between 2% and 6% of patients. We examined axial fluoroscopic views of the distal end of the radius to observe small amounts of dorsal screw penetration, and determined the ideal angle of inclination of the x-ray beam to the forearm when making this radiological view. Six volar locking plates were inserted at the wrists of cadavers. The actual screw length was measured under direct vision through a dorsal approach to the distal radius. Axial radiographs were performed for different angles of inclination of the forearm at the elbow. Comparing axial radiological measurements and real screw length, a statistically significant correlation could be demonstrated at an angle of inclination between 5° and 20°. The ideal angle of inclination required to minimise the risk of implanting over-long screws in a dorsal horizon radiological view is 15°.

Ewing sarcoma versus osteomyelitis: differential diagnosis with magnetic resonance imaging.

OBJECTIVE: To find and evaluate characteristic magnetic resonance imaging (MRI) patterns for the differentiation between Ewing sarcoma and osteomyelitis. MATERIALS AND METHODS: We identified 28 consecutive patients referred to our department for MRI (1.5 T) of an unclear bone lesion with clinical symptoms suggestive of Ewing sarcoma or osteomyelitis. MRI scans were re-evaluated by two experienced radiologists, typical MR imaging features were documented and a diagnostic decision between Ewing sarcoma and osteomyelitis was made. Statistical significance of the association between MRI features and the biopsy-based diagnosis was assessed using Fisher's exact test. RESULTS: The most clear-cut pattern for determining the correct diagnosis was the presence of a sharp and defined margin of the bone lesion, which was found in all patients with Ewing sarcoma, but in none of the patients with osteomyelitis (P < 0.0001). Contrast enhancing soft tissue was present in all cases with Ewing sarcoma and absent in 4 patients with osteomyelitis (P = 0.0103). Cortical destruction was found in all patients with Ewing sarcoma, 4 patients with osteomyelitis did not present any cortical reaction (P = 0.0103). Cystic or necrotic areas were identified in 13 patients with Ewing sarcoma and in 1 patient with osteomyelitis (P = 0.004). Interobserver reliability was very good (kappa = 1) in Ewing sarcoma and moderate (kappa = 0.6) in patients with osteomyelitis. CONCLUSIONS: A sharp and defined margin, optimally visualized on T1-weighted images in comparison to short tau inversion recovery (STIR) images, is the most significant feature of Ewing sarcoma in differentiating from osteomyelitis.

Accessory or additional renal arteries show no relevant effects on the width of the upper urinary tract: a 64-slice multidetector CT study in 1072 patients with 2132 kidneys.

OBJECTIVE: The aim of this study was to find out on an unselected patient group whether crossing vessels have an influence on the width of the renal pelvis and what independent predictors of these target variables exist. METHODS: In this cross-sectional study, 1072 patients with arterially contrasted CT scans were included. The 2132 kidneys were supplied by 2736 arteries. RESULTS: On the right side, there were 293 additional and accessory arteries in 286 patients, and on the left side there were 304 in 271 patients. 154 renal pelves were more than 15 mm wide. The greatest independent factor for hydronephrosis on one side was hydronephrosis on the contralateral side (p<0.0001 each). Independent predictors for the width of the renal pelvis on the right side were the width of the renal pelvis on the left, female gender, increasing age and height; for the left side, predictors were the width of the renal pelvis on the right, concrements, parapelvic cysts and great rotation of the upper pole of the kidney to dorsal. Crossing vessels had no influence on the development of hydronephrosis. Only anterior crossing vessels on the right side are associated with widening of the renal pelvis by 1 mm, without making it possible to identify the vessel as an independent factor in multivariate regression models. CONCLUSION: The width of the renal pelvis on the contralateral side is the strongest independent predictor for hydronephrosis and the width of the renal pelvis. There is no link between crossing vessels and the width of the renal pelvis.

Endovascular repair or medical treatment of acute type B aortic dissection? A comparison.

INTRODUCTION: The aim of this retrospective study was to compare the outcome of thoracic endovascular aortic repair (TEVAR) to that of medical therapy in patients with acute type B aortic dissection (TBD). MATERIALS AND METHODS: From July 1996 to April 2008, 88 patients presenting with acute TBD underwent either TEVAR (group A, n=38) or medical therapy (group B, n=50). Indications for TEVAR were intractable pain, aortic branch compromise resulting in end-organ ischemia, rapid aortic dilatation and rupture. Follow-up was performed postinterventionally, at 3, 6 and 12 months and yearly thereafter and included clinical examinations and computed tomography (CT), as well as aortic diameter measurements and assessment of thrombosis. RESULTS: Mean follow-up was 33 months in group A and 36 months in group B. The overall mortality rate was 23.7% in group A and 24% in group B, where 4 patients died of late aortic rupture. In group A, complications included 9 endoleaks and 4 retrograde type A dissections, 3 patients were converted to open surgery and 2 needed secondary intervention. None of the patients developed paraplegia. In group B, 4 patients were converted to open surgery and 2 to TEVAR. The maximal aortic diameter increased in both groups. Regarding the extent of thrombosis, our analyses showed slightly better overall results after TEVAR, but they also showed a tendency towards approximation between the two groups during follow-up. CONCLUSION: TEVAR is a feasible treatment option in acute TBD. However, several serious complications may occur during and after TEVAR and it should therefore be reserved to patients with life-threatening symptoms.

Time-dependent association of total serum cholesterol and cancer incidence in a cohort of 172,210 men and women: a prospective 19-year follow-up study.

BACKGROUND: The relationship between serum cholesterol and cancer incidence remains controversial. PATIENTS AND METHODS: We investigated the association of total serum cholesterol (TSC) with subsequent cancer incidence in a population-based cohort of 172 210 Austrian adults prospectively followed up for a median of 13.0 years. Cox regression, allowing for time-dependent effects, was used to estimate adjusted hazard ratios (HRs) with 95% confidence intervals (95% CIs) for the association of TSC with cancer. RESULTS: We observed pronounced short-term associations of TSC and overall cancer incidence in both men and women. For malignancies diagnosed shortly (<5 months) after baseline TSC measurement, the highest TSC tertile (>235.0 mg/dl in men and >229.0 in women) compared with the lowest tertile (<194.0 mg/dl in men and <190.0 in women) was associated with a significantly lower overall cancer risk [HR = 0.58 (95% CI 0.43-0.78, P(trend) = 0.0001) in men, HR = 0.69 (95% CI 0.49-0.99, P(trend) = 0.03) in women]. However, after roughly 5 months from baseline measurement, overall cancer risk was not significantly associated with TSC. The short-term inverse association of TSC with cancer was mainly driven by malignancies of the digestive organs and lymphoid and hematopoietic tissue. CONCLUSION: The short-term decrease of cancer risk seen for high levels of TSC may largely capture preclinical effects of cancer on TSC.

Detecting prostate cancer by intracellular macrophage prostate-specific antigen (PSA): a more specific and sensitive marker than conventional serum total PSA.

BACKGROUND: Serum prostate-specific antigen (PSA) is a standard method and a widely used marker for prostate cancer, but it has a poor specificity for early detection. Herein we demonstrate that intracellular macrophage PSA (imPSA) enables screening and differentiation between benign and malignant prostate disease. MATERIALS AND METHODS: The efficacy of intracellular macrophage PSA in circulating and tissue macrophages was therefore investigated in a double-centre study of 38 prostate cancer patients and 36 healthy controls by fluorescent-activated cell sorting analysis and immunohistology. RESULTS: Both methods uncovered the existence of PSA-positive macrophages specific for patients with prostate cancer. In addition, we demonstrate the superiority of our new test over standard serum total PSA in a blinded double-centre trial. ImPSA had a marked higher sensitivity and specificity than serum total PSA (imPSA: sensitivity 92%, specificity 92%, positive predictive value 92%; serum total PSA: sensitivity 79.5%, specificity 87.5%, positive predictive value 26.8%). CONCLUSION: In this study, we demonstrate that imPSA is a new prostate cancer screening method that is highly sensitive and more specific than standard PSA testing.

Microcoil embolization of an arteriovenous fistula from the arteria bulbi penis to the corpus spongiosum penis in the treatment of erectile dysfunction: normal function regained immediately after intervention.

A 39-year-old man presented with erectile dysfunction that had persisted since its sudden onset 5 years ago. He exhibited none of the classic risk factors, and all attempts at medication had been unsuccessful. An ultrasound examination revealed the presence of an arteriovenous shunt in the corpus spongiosum penis. Selective digital subtraction angiography of the left internal pudendal artery showed an arteriovenous fistula from the arteria bulbi penis to the corpus spongiosum penis. The outflow of venous blood took place via the penile veins into the periprostatic vein plexus. Superselective catheterization of the arteria bulbi penis was performed with a 3 French coaxial catheter (Topaz Micro Coils; Micro Therapeutics, Inc, Irvine, CA) and it was occluded by inserting several platinum coils. 1 week after the procedure, the patient reported normal erectile function, which was subsequently maintained.

Postinterventional volume dynamics following endovascular treatment of infrarenal aortic aneurysms.

AIM: Endovascular treatment of infrarenal aortic aneurysms requires follow-up to rule out complications that would require renewed intervention. The aim of this study was to define those factors which, in the absence of such complications, could be relevant for the remaining risk. METHODS: The CT data sets of 55 patients (73.5+/-8 years; M: F ratio 49: 6) were evaluated volumetrically: immediately postinterventional, 6 months, and annually after the procedure. The median observation period was 30+/-19 months. RESULTS: Risk factors for a further increase in aneurysm volume were: short-term increase in volume >5%, medium-term growth >20%, one-time growth >20%, no decrease in volume, and an initial aneurysm volume >200 mL. Favorable factors were: a one-time decrease in volume >15% and no increase in volume at any follow-up visit. Indifferent factors were: initial decrease in volume, one-time growth <20%, one-time shrinkage <15%, and type II endoleak. Conclusion. Patients require particular attention whose aneurysm volume increased by more than 5% or increased medium-term or increased at once by more than 20%, and who either did not show a decrease in volume at any follow-up or who had a large initial volume. A one-time decrease in volume of more than 15% was positive, as was no increase in volume at any follow-up.

Placement of endovascular stent-grafts for emergency repair of acute traumatic aortic rupture: a single-centre experience.

The aim of this retrospective study was to evaluate mid- and long-term results of endovascular stent-graft placement for emergency repair of acute traumatic thoracic aortic rupture. From 1996 through 2005, 22 consecutive patients (mean age: 38.7 years) underwent endovascular repair of acute traumatic thoracic aortic rupture located at the aortic isthmus in most cases. All patients were at high surgical risk due to severe associated injuries. The endografts were inserted via femoral or iliac artery access under fluoroscopic guidance. Follow-up was performed postinterventionally, at 6 and 12 months and yearly thereafter, and included clinical examination and computed tomography (CT) scans. Technical and clinical success rates were 86.3%. Mean follow-up was 31.7 months. Three patients developed early type I endoleak due to the inability of the rigid graft to adapt to the curved aortic contour. In two of them conversion to open surgery was necessary. One patient had late type I endoleak and died. No other complications were observed. The outcome was successful in most patients. The mid- and long-term results of our current study are promising. However, early type I endoleak represents a problem, especially in adolescent patients with a marked curvature of the aortic arch.

The vasodepressor function of the kidney: prostaglandin E2 is not the principal vasodepressor lipid of the renal medulla.

AIM: Whereas prostaglandin E2 has been characterized as the principal vasodepressor lipid, medullipin remains a hypothetical vasodepressor principle of the renal medulla. Representing the first step towards the isolation of medullipin as a pure compound, the aim of the present study was to determine whether or not the known vasodilator and antihypertensive action of prostaglandins play a role in the antihypertensive activity of renal medulla. METHODS: A chloroform extract of porcine kidney medulla was fractionated by gradient vacuum liquid chromatography (VLC) and analysed by capillary GC-MS for the presence of prostaglandins (detection limit: 2.2 ppm). The biological activity was determined in spontaneously hypertensive Wistar rats. The particle size of injectable colloids prepared from extract and fractions was controlled by photon correlation spectroscopy. RESULTS: The extract caused a pronounced blood pressure decline (29.6 +/- 6.3/24.9+/- 5.5 mmHg; P = 0.0078; 10 mg kg(-1) body weight; particle size of 143 +/- 18 nm; n = 7) lasting for more than 1 h. The heart rate remained stable, showing only a slightly decrease. All fractions were shown to be devoid of vasodilator prostanoid substances. The VLC procedure allowed the successful separation of endogenous emulsifiers from the active principle. An extract from the renal cortex did not exhibit a similar vasodepressor effect. CONCLUSION: Prostaglandins are excluded as the blood pressure-lowering active principle of a total lipid kidney medulla extract. The vasodepressor principle is contained in the kidney medulla, but not in the cortex. It can be separated from endogenous emulsifying substances, is chromatographically stable, and is amenable to purification and chemical characterization.

Clinical differences between benign and malignant pheochromocytomas.

Most pheochromocytomas can be cured by resection. In view of the unfavourable prognosis for surgical therapy in cases of late tumour detection and malignant tumours, the aim of the present study is to differentiate between typical signs and symptoms of malignant versus benign pheochromocytomas. We investigated the records of 133 patients retrospectively (1967-1998). In cases of benign tumours (104 of 133, mean age 42+/-15.8 years) tumour size was 5.9+/-3.4 cm, and history was 47.4+/-75.4 months. 7.7% of the tumours were extraadrenal, and 77% had paroxysmal manifestations. The other 29 patients (mean age: 39.2+/-21.9 years) had malignant lesions (tumour size: 9.4+/-5.9 cm (p=0.0022); history: 7.4+/-5.6 months (p=0.0137); extraadrenal: 24.1% (p=0.0219); paroxysmal: 37.9% (p=0.0012)). Symptoms of patients with benign tumours were hypertension (80%), headaches (42.3%), sweating (30.8%), tachycardia (26%) and pallor (24%) (Malignant: Hypertension 46%, p=0.0873; headaches 11%, p=0.0008; sweating 11%, p=0.0196; tachycardia 14%, p=0.1961 and pallor 0%, p=0.0010). Abdominal pain and dorsalgia occurred more frequently in malignant pheochromocytomas (26% versus 7%, p=0.0014). Unusually short histories and extraadrenal localization appear to be suspicious for malignancy. The "typical" clinical signs and symptoms occur more frequently in patients with benign tumours and can therefore be regarded as typical signs of benign pheochromocytomas.

A possible explanation for the frequent concomitance of arterial hypertension and multiple renal arteries.

In more than 20% of subjects, at least one kidney is found to be supplied by more than one artery arising from the aorta. This aberrant renovascular anatomy has been reported in the literature to occur in up to 80% of patients who suffer from essential hypertension. Predominant numbers of the so-called 'accessory' vessels are longer and narrower than the segmental arteries arising in the main renal artery. As a result (in accordance with Poiseuille's law of fluid flow), the renal segments supplied by these 'accessory' vessels may have lower levels of blood pressure than the remainder of the parenchyma, thereby increasing the renin secretion. This hypothesis could be significant in terms of finding a causal treatment for a disorder induced by such a mechanism. We first review the literature in which the frequency of these vascular anomalies in normotensive and hypertensive patients is described, and then advance a hypothesis explaining the frequent incidence of essential hypertension in these subjects, as well as the ramifications of this phenomenon.