Corona again? SSC after a severe COVID-disease.

Secondary sclerosing cholangitis (SSC) is a severe complication of intensive care treatment in critically ill patients. It is characterized by rapid onset and severe chlolestasis with elevation of gGT. In contrast to primary sclerosing cholangitis, SSC-CIP has a distinct and timely well defined trigger and can have a rapid progress to cirrhosis and liver failure. In context of the COVID-19-pandemic, there are reports about patients, who developed SSC after a severe COVID-infection and intensive care treatment.We report on a 62-year old patient without any relevant pre-existing illnesses, who suffered from severe COVID-19 pneumonia with the need for long term ventilation. In the course of the disease he developed a critical-illness-polyneuropathy a pronounced cholestasis. After recovery from COVID-pneumonia, the PNP regressed but the cholestasis progressed. MRCP showed only irregular intrahepatic bile ducts, while EUS showed echogenic intraductal longitudinal structures characteristic for intraductal casts and for SSC-CIP. This was confirmed with ERC, where the complete necrotic bile ducts could be extracted and retrieved for histological and molecular analysis.The patient was included in a scheduled ERC-program to prevent a progress of SSC and the concomitant cirrhosis.SSC is an often missed diagnosis, which obviously can also occur in COVID-patients. In case of elevated liver function tests with cholestasis, EUS might be the key diagnostic method to characterize intraductal casts and identify those patients who should undergo ERC.

Clinical value of [18F]FDG-PET/CT and 3D-black-blood 3T-MRI for the diagnosis of large vessel vasculitis and single-organ vasculitis of the aorta.

BACKGROUND: We aimed to investigate the clinical value of a 3D-T1w turbo-spin-echo (TSE) sequence and [18F]fluorodeoxyglucose positron emission tomography/computed tomography ([18F]FDG-PET/CT) for the diagnosis of active large vessel vasculitis (LVV) and single-organ vasculitis (SOV) of the aorta. METHODS: Twenty-four patients with suspected vasculitis who underwent MRI and PET/CT were retrospectively evaluated. MRI was analyzed for concentric contrast enhancement and wall thickening, and flow artifact intensity (4-point-scales). PET/CT analysis comprised qualitative, quantitative and semiquantitative methods. Imaging findings were correlated with final diagnosis derived from the clinical follow-up data. RESULTS: Fifteen of 24 patients had a clinically confirmed active vasculitis, two had inactive vasculitis and 7 no vasculitis. [18F]FDG-PET/CT and 3D-T1w TSE-MRI revealed both a high diagnostic accuracy of 88% and 83%, respectively. In patients in whom both PET/CT and MRI showed concordant findings (19 patients), the accuracy increased to 95% with a high positive predictive value (92%) and negative predictive value (100%); thus, a correct diagnosis was obtained in 18 of 19 patients. Among the five patients with discordant findings PET/CT correctly identified the two patients without active vasculitis while rated false positive on MRI. Of the three remaining patients with active vasculitis, two were correctly identified by MRI and one by PET/CT. CONCLUSIONS: 3D-T1w TSE-MRI and [18F]FDG-PET/CT are both useful in the diagnosis of active vasculitis with high diagnostic accuracies. The diagnostic accuracy was even optimized by combining the two analysis methods. Therefore, there might be substantial potential for the application of whole-body hybrid PET/MRI in the evaluation of vasculitis in future studies.

A pitfall of bilateral inferior petrosal sinus sampling in cyclic Cushing's syndrome.

BACKGROUND: Clinical care of patients with cyclic Cushing's syndrome (CS) is challenging. Classical pitfalls include incorrect subtyping, unnecessary surgical procedures and delayed definite treatment. CASE PRESENTATION: A 43-year-old female suffered from a rapidly cycling ectopic CS. She experienced six cycles of severe hypercortisolism within a 2 year period (maximum plasma cortisol 5316 nmol/L, normal range 124.2-662.4 nmol/L; maximum urinary free cortisol 79,469 nmol/24 h, normal range < 414 nmol/24 h) lasting 2-9 weeks. The episodes were associated with pronounced hypokalemia (lowest K+ value recorded 2.4 mmol/l) and progressive signs and symptoms of CS. A bilateral inferior petrosal sinus sampling (BIPSS) performed during a trough phase was false positive for pituitary ACTH overproduction resulting in unnecessary transsphenoidal surgery while a second BIPSS performed during an active phase was indicative for ectopic CS. The 18F-DOPA PET/CT showed a pancreatic lesion, which was subsequently partially removed. Surprisingly, the histopathology was conclusive for ACTH-positive lymph node metastasis located in the retro-duodenal tissue of an occult neuroendocrine tumor WHO grade II. The primary tumor has not been identified so far and, because of the persistent hypercortisolism, the patient underwent bilateral adrenalectomy. Two years later, ACTH levels started to increase progressively. Percutaneous biopsy of a newly identified suspected lesion in the fifth thoracic vertebra revealed a metastasis with positive staining for ACTH, synaptophysin and chromogranin A. Therapy with carboplatin and etoposide was started and, since then, the patient underwent 12 cycles of chemotherapy. CONCLUSIONS: We report the challenging case of a rapidly cycling CS secondary to ACTH-secreting neuroendocrine intestinal tumor of unknown primary. We highlight the importance of performing diagnostic tests only during the phases of active cortisol secretion and as soon as first symptoms appear to avoid pitfalls.

Assessment of Disease Activity in Takayasu Arteritis: Potential Role of Contrast-Enhanced Ultrasound.

PURPOSE: To assess the diagnostic value of intima media thickness measurements and contrast-enhanced ultrasound (CEUS) of the supraaortic arteries in the assessment of disease activity in Takayasu arteritis (TA). MATERIALS AND METHODS: Patients with TA and involvement of the carotid and/or subclavian/axillary arteries underwent CEUS imaging in addition to B-mode and color duplex ultrasound. The maximum IMT (mIMT) was measured and high-resolution CEUS of the most prominently thickened vessel segment was performed. Two blinded readers reviewed the CEUS movies, with semiquantitative assessment of microbubble enhancement of the arterial wall (grade 0: no or minimal; grade 1: moderate; grade 2: pronounced). Clinical symptoms, acute phase reactants, and established indices of clinical disease activity (NIH criteria, ITAS score) were recorded. RESULTS: 40 examinations in 17 patients were analyzed. According to clinical judgement, 27 and 13 cases were classified as clinically inactive and active, respectively. An mIMT-cutoff of > 2.7 mm identified active disease with a sensitivity and specificity of 69.2 % and 88.9 %, respectively (area under the curve 0.83). The interobserver agreement of CEUS analysis was substantial (Cohen's kappa 0.76). By consensus reading, 17, 15, and 8 cases were classified as uptake grade 0, grade 1 and grade 2, respectively. Grade 0 uptake was exclusively present in 17 clinically inactive patients. Grade 1 uptake was seen in 10 patients with clinically inactive disease and 5 patients with clinically active disease. Grade 2 uptake was exclusively present in 8 patients with active disease. CONCLUSION: Both sonographic IMT measurements and high-resolution CEUS are promising in the ad-hoc assessment of disease activity in patients with TA.

Relapses in three patients with Takayasu arteritis under tocilizumab treatment detected by contrast enhanced ultrasound.

Takayasu arteritis (TA) is a rare large vessel vasculitis, affecting the aorta and its major branches, typically in young women. In this case report, we present three cases of young women of Caucasian descent who experienced relapses while under treatment with the monoclonal humanized antibody to the interleukin 6 receptor, tocilizumab. Active vasculitic lesions of the supraaortic (common carotid and axillary) arteries were detected and characterized via high resolution contrast enhanced ultrasound. Based on these cases, we discuss the potential role of contrast enhanced ultrasound in the diagnosis and follow-up of TA as well as the current data on the efficacy of tocilizumab in the treatment of TA.

Altered renal functions in patients with occlusion of an accessory renal artery after endovascular stenting of an infrarenal aneurysm.

OBJECTIVE: Coverage of an accessory renal artery (ARA) during endovascular aneurysm repair (EVAR) may result in renal infarction (RI) or decline in renal function. Until now, it remains vague which patients are at risk to develop these complications. We therefore analyzed the effect of ARA sealing by EVAR with respect to the occurrence of RI and renal function. METHODS: A retrospective analysis of the medical records and computed tomographic scans of patients who underwent EVAR within a period of 5 years was performed. Particular attention was paid to the presence or absence of accessory renal arteries and renal function before EVAR. Thirty-four patients with ARA were matched 1:3 to 102 patients without ARA. The results after EVAR were analyzed in patients with and without ARA. In patients with ARA, we further examined the results after EVAR in patients with an estimated glomerular filtration rate (eGFR) ≥ 60 mL/min and eGFR < 60 mL/min before EVAR. RESULTS: Before EVAR, the median eGFR was 74 mL/min (25th/75th percentiles, 57/89) in patients with ARA and 72 mL/min (25th/75th percentiles, 63/87) in patients without ARA. Alterations in eGFR were significantly pronounced in patients with ARA when compared with patients without ARA 1 week after EVAR (ARA, -10.7 ± 16.9 mL/min vs without ARA, 1.2 ± 13.3 mL/min; P = .002) and after 6 months (ARA, -10.8 ± 17.4 mL/min vs without ARA, 1.2 ± 13.3 mL/min; P = .001). RI only occurred in patients with ARA. Within the group of patients with ARA, patients with normal renal function (NF) showed a more pronounced decline in eGFR preoperatively when compared with patients with impaired renal function (IF) 1 week after EVAR (NF, -14.3 ± 18.0 mL/min vs IF, -1.3 ± 10.8 mL/min; P = .02) and after 6 months (NF, -15.8 ± 17.9 mL/min vs IF, 0.1 ± 15.2 mL/min; P = .007). CONCLUSIONS: The decrease in renal function was more pronounced in patients with ARA after EVAR when compared with patients without ARA undergoing EVAR. In patients with ARA, the observed decline in renal function was significantly distinct in patients presenting NF preoperatively. Consequently, the risk of IF after EVAR seems to be increased in patients with ARA and normal preoperative renal function.

Evolution of patency rates of self-expandable bare metal stents for endovascular treatment of femoro-popliteal arterial occlusive disease: Does stent design matter?

OBJECTIVE: To analyse the patency rates of femoro-popliteal stenting with different self-expandable Nitinol stent-designs. METHODS: Two hundred and twenty-two patients (142 (64%) male; age 72.4 ± 11.6 years) with symptomatic femoro-popliteal peripheral arterial occlusive disease (PAOD) underwent percutaneous transluminal angioplasty (PTA) and stenting with three different Nitinol stents (interwoven IW: n = 70; closed-cell CC: n = 85; open-cell OC: n = 67). One-year post-procedural target lesion revascularization (TLR_12M) rates were investigated with regard to co-morbidities: diabetes (DBM), hyperlipidaemia (HLP), hypertension (RR), coronary artery disease (CAD) and degree of calcification. RESULTS: Twelve-month follow-up data were available for 60, 69 and 50 patients in the IW, OC and CC groups (179 patients in total). The cumulative patency (IW: 52 (86.7%); OC: 50 (72.5%); CC: 23 (46.0%); P < 0.001) and the TLR_12M rates (IW: 8 (13.3%); OC: 19 (27.5%); CC: 27 (54.0%); P < 0.001) differed significantly, as did the subgroup analyses (DBM: P = 0.05; RR: P = 0.003; HLP: P = 0.005; CAD: P = 0.02; localization: P < 0.001; calcification: P < 0.001), with the best patency for the IW stent and the highest TLR_12M for the CC stent. CONCLUSION: The interwoven stent-design was superior to the standard open- and closed-cell stent-designs in endovascular treatment of femoro-popliteal PAOD in a follow-up period of 12 months. KEY POINTS: • Results of femoro-popliteal stenting are still unsatisfactory. • Comparative studies for currently available different Nitinol stent-designs are lacking. • This is a first comparative study on long-term patency of different Nitinol stent-designs. • Interwoven stent-design leads to improved long-term patency. • Interwoven stent-design leads to lower TLR than other stent-designs.

3D-black-blood 3T-MRI for the diagnosis of thoracic large vessel vasculitis: A feasibility study.

OBJECTIVES: To evaluate the feasibility of T1w-3D black-blood turbo spin echo (TSE) sequence with variable flip angles for the diagnosis of thoracic large vessel vasculitis (LVV). METHODS: Thirty-five patients with LVV, diagnosed according to the current standard of reference, and 35 controls were imaged at 3.0T using 1.2 × 1.3 × 2.0 mm3 fat-suppressed, T1w-3D, modified Volumetric Isotropic TSE Acquisition (mVISTA) pre- and post-contrast. Applying a navigator and peripheral pulse unit triggering (PPU), the total scan time was 10-12 min. Thoracic aorta and subclavian and pulmonary arteries were evaluated for image quality (IQ), flow artefact intensity, diagnostic confidence, concentric wall thickening and contrast enhancement (CWT, CCE) using a 4-point scale. RESULTS: IQ was good in all examinations (3.25 ± 0.72) and good to excellent in 342 of 408 evaluated segments (83.8 %), while 84.1 % showed no or minor flow artefacts. The interobserver reproducibility for the identification of CCE and CWT was 0.969 and 0.971 (p < 0.001) with an average diagnostic confidence of 3.47 ± 0.64. CCE and CWT were strongly correlated (Cohen's k = 0.87; P < 0.001) and significantly more frequent in the LVV-group (52.8 % vs. 1.0 %; 59.8 % vs. 2.4 %; P < 0.001). CONCLUSIONS: Navigated fat-suppressed T1w-3D black-blood MRI with PPU-triggering allows diagnosis of thoracic LVV. KEY POINTS: • Cross-sectional imaging is frequently applied in the diagnosis of LVV. • Navigated, PPU-triggered, T1w-3D mVISTA pre- and post contrast takes 10-12 min. • In this prospective, single-centre study, T1w-3D mVISTA accurately depicted large thoracic vessels. • T1w-3D mVISTA visualized CWT/CCW as correlates of mural inflammation in LVV. • T1w-3D mVISTA might be an alternative diagnostic tool without ionizing radiation.

B-mode sonography wall thickness assessment of the temporal and axillary arteries for the diagnosis of giant cell arteritis: a cohort study.

OBJECTIVES: We aimed to determine the diagnostic accuracy of B-mode compression sonography of the temporal arteries (tempCS) and B-mode sonographic measurement of the axillary artery intima media thickness (axIMT) for the diagnosis of giant cell arteritis (GCA). METHODS: After having established measurement of tempCS and axIMT in our routine diagnostic workup, 92 consecutive patients with a suspected diagnosis of GCA were investigated. Clinical characteristics were recorded and wall thickening of the temporal arteries (tempCS) and axillary arteries (axIMT) was measured (mm). Using the final clinical diagnosis as the reference standard, receiver operator characteristics (ROC) analysis was performed. In a subgroup of 26 patients interobserver agreement was assessed using Spearman's rank correlation. RESULTS: Cranial GCA, extracranial GCA, and combined cranial/extracranial GCA were diagnosed in 18, 7, and 9 individuals, respectively. For the diagnosis of cranial GCA, tempCS had an excellent area under the curve (AUC) of 0.95, with a cut-off of ≥0.7 mm offering a sensitivity and specificity of 85% and 95%. The AUC of axIMT for the diagnosis of extracranial GCA was 0.91 (cut-off ≥1.2 mm: sensitivity and specificity 81.3 and 96.1%). Applying a combined tempCS/axIMT cut-off of ≥0.7mm/1.2 mm, we calculated an overall sensitivity and specificity for the final clinical diagnosis of cranial and/or extracranial GCA of 85.3% and 91.4%. Interobserver agreement was strong for both parameters assessed (Spearman's rho 0.72 and 0.77, respectively). CONCLUSIONS: The combination of tempCS/axIMT allows objective sonographic assessment in suspected GCA with promising diagnostic accuracy.

Rationale and design of the RECording COurses of vasculaR Diseases registry (RECCORD registry).

BACKGROUND: The prevalence of peripheral artery disease (PAD) is increasing worldwide. Revascularization procedures constitute a cornerstone of the therapy in PAD, not only in critical limb ischaemia but increasingly also in patients with intermittent claudication. The German Society of Angiology - Society for Vascular Medicine is establishing a nationwide, prospective, multicentre registry to address the lack of contemporary real life data regarding current practice of medical and interventional care in vascular patients and its subsequent long-term outcome. PATIENTS AND METHODS: The RECording COurses of vasculaR Diseases registry (RECCORD registry) is an observational, prospective, multicentre, all-comers registry platform. In the initial phase, patients referred for endovascular revascularization of PAD of the lower limbs will be prospectively included and followed up for at least one year. At baseline, data on patients' demographic characteristics, comorbidities, previous peripheral interventions, medication, and clinical stage of PAD (Rutherford category), haemodynamic parameters, and procedural data including complications will be assessed. Major adverse cardiac and limb events will be recorded at planned (at six and 12 months) and at any unplanned visits. The therapeutic management will be exclusively left to the discretion of the vascular specialists. RESULTS AND CONCLUSIONS: The RECCORD registry will provide a comprehensive dataset depicting the current real life practice and outcome of vascular care. The seven predefined quality indicators will be used for benchmarking the participating centres. Moreover, identifying factors promoting a favourable outcome might pave the way for an evidence-based therapeutic strategy and a dedicated therapeutic pathway for patients with PAD including patient-oriented best interventional approaches. In the future, the RECCORD registry may provide a general platform to study the courses of various defined vascular diseases in order to get detailed insights into the real life current practice of health care provided to vascular patients.

Mass Spectrometry-Based Adrenal and Peripheral Venous Steroid Profiling for Subtyping Primary Aldosteronism.

BACKGROUND: Differentiating patients with primary aldosteronism caused by aldosterone-producing adenomas (APAs) from those with bilateral adrenal hyperplasia (BAH), which is essential for choice of therapeutic intervention, relies on adrenal venous sampling (AVS)-based measurements of aldosterone and cortisol. We assessed the utility of LC-MS/MS-based steroid profiling to stratify patients with primary aldosteronism. METHODS: Fifteen adrenal steroids were measured by LC-MS/MS in peripheral and adrenal venous plasma from AVS studies for 216 patients with primary aldosteronism at 3 tertiary referral centers. Ninety patients were diagnosed with BAH and 126 with APAs on the basis of immunoassay-derived adrenal venous aldosterone lateralization ratios. RESULTS: Among 119 patients confirmed to have APAs at follow-up, LC-MS/MS-derived lateralization ratios of aldosterone normalized to cortisol, dehydroepiandrosterone, and androstenedione were all higher (P < 0.0001) than immunoassay-derived ratios. The hybrid steroids, 18-oxocortisol and 18-hydroxycortisol, also showed lateralized secretion in 76% and 35% of patients with APAs. Adrenal venous concentrations of glucocorticoids and androgens were bilaterally higher in patients with BAH than in those with APAs. Consequently, peripheral plasma concentrations of 18-oxocortisol were 8.5-fold higher, whereas concentrations of cortisol, corticosterone, and dehydroepiandrosterone were lower in patients with APAs than in those with BAH. Correct classification of 80% of cases of APAs vs BAH was thereby possible by use of a combination of steroids in peripheral plasma. CONCLUSIONS: LC-MS/MS-based steroid profiling during AVS achieves higher aldosterone lateralization ratios in patients with APAs than immunoassay. LC-MS/MS also enables multiple measures for discriminating unilateral from bilateral aldosterone excess, with potential use of peripheral plasma for subtype classification.

Safety and efficiency of femoral artery access closure with a novel biodegradable closure device: a prospective single-centre pilot study.

OBJECTIVES: Vascular closure devices can accelerate haemostasis after arteriotomy, but induce scarring. The aim of the study was to prospectively analyse the feasibility of a novel biodegradable arterial closure device (CD). METHODS: Two hundred fifty-five patients (183 male; age 36-98 years) with an access vessel diameter >3 mm received the biodegradable CD after endovascular therapy. Technical success rate, time-to-haemostasis (TTH) and time-to-ambulation (TTA) were measured. Puncture site complications were categorized as minor (local hematoma, minor bleeding) or major (pseudoaneurysm, embolization, dissection, thrombotic occlusion, hematoma/major bleeding requiring surgery, access site infection). RESULTS: Technical success was achieved in 98.8 % (252 cases); device failure occurred in three cases (1.2 %). The average TTH and TTA were 11.3 ± 26.9 s and 73.0 ± 126.3 min. The major complication rate was 1.6 %, with three pseudoaneurysms and one retroperitoneal bleeding. The minor complication rate was 2.0 %, with five small hematomas. Neither cardiovascular risk factors nor access vessel characteristics had statistically significant influence on adverse events. Re-puncture was uncomplicated in 32 cases after 155.0 ± 128.8 days. CONCLUSIONS: Handling of the new biodegradable CD is safe. The complication rates are tolerably low and comparable to other CDs. Post-procedural sonography showed no significant palpable subcutaneous changes in the access site. KEY POINTS: • VCDs can increase time efficiency and patient comfort after intervention. • In this prospective single-centre-study, biodegradable CD was safe and easily applicable. • Its major and minor complication rates are comparable to other CDs. • Its mean time-to-haemostasis and time-to-ambulation were 11.3 ± 26.9 s and 73.0 ± 126.3 min. • Post-procedural sonography showed no significant palpable subcutaneous changes at the access site.

Combined Carotid Endarterectomy and Retrograde Stenting of the Supra-Aortic Trunk: Does Cervical Block Offer Advantages?

BACKGROUND: Atherosclerosis of the carotid artery is a major source of stroke. In some cases, atherosclerosis occurs at several positions within the carotid artery. Carotid endarterectomy (CEA) in combination with retrograde balloon angioplasty and stenting of a brachiocephalic or common carotid artery stenosis has been described as efficacious and safe procedure to prevent stroke in these cases. The aim of this study was to analyze the impact of anesthetic techniques on hemodynamic factors, operation time, duration of clamping, and postoperative pain. METHODS: A retrospective analysis of patients undergoing CEA in combination with retrograde stenting under either general anesthesia (GA) or cervical block (CB) was carried out. Preoperative risk factors were analyzed as well as operating and cross-clamping time, hemodynamic factors, perioperative complications, postoperative pain, application of pain killers, and duration of intensive care unit (ICU) and hospital stay. RESULTS: Operating (GA: 193 ± 91 min vs. CB: 125 ± 52 min, P = 0.029) and cross-clamping time (GA: 34 ± 12 min vs. CB: 26 ± 9 min, P < 0.001) were shorter under CB. Patients under CB were hemodynamically more stable and required less norepinephrine (GA: 1.1 ± 0.6 mg vs. CB: 0.1 ± 0.1 mg, P < 0.001) and crystalloids (GA: 2,813 ± 1,173 mL vs. CB: 1,088 ± 472 mL, P < 0.001). Postoperative pain levels (GA: numeric rating scale 4.3/10 vs. 2.0/10; P = 0.004) and requirement of pain killers were also lower within the CB group. CONCLUSIONS: Synchronous CEA and retrograde balloon angioplasty and stenting of a brachiocephalic or common carotid artery stenosis under CB is associated with reduction of operating and cross-clamping time, improved hemodynamical stability, lower postoperative pain, shorter ICU and hospital stay, and it offers the advantage of a continuous neurological monitoring.

Treatment of male varicoceles by transcatheter polidocanol foam sclerotherapy: evaluation of clinical success, complications, and patients' satisfaction with regard to alternative techniques.

OBJECTIVES: We report our experience with polidocanol foam sclerotherapy with no additional coils, evaluating clinical success, patients' satisfaction, and complications. METHODS: We conducted a retrospective study of 141 patients with 146 varicoceles (mean age: 29.3 years; range: 13 - 60 years) who underwent foam sclerotherapy with polidocanol 2% (range: 2 - 12 ml) in an outpatient setting between January 2007 and December 2013. For the follow-up, telephone interviews with the patients were conducted (mean follow-up time: 46.4 months, standard deviation: 20.17 months). RESULTS: The technical success rate was 91.8%. There was a 55.8% response rate to the telephone interviews. Follow-up revealed a clinical success rate of 83.9% and a persistence or relapse rate of 16.1%. Of the patients, 81.9% were absolutely satisfied with the outcome. In 94.9% of cases, pain or discomfort resolution was reported, and in 97% of cases, aesthetic issues were no longer a problem. Of partners, 63.2% achieved pregnancy, and in 50% of patients with preprocedural testicular atrophy, catch-up growth was observed. One patient with pampiniform plexus phlebitis received inpatient treatment with no long-term damage recorded. CONCLUSIONS: Polidocanol foam varicocele sclerotherapy is a safe and effective procedure, with a high rate of patients' satisfaction, clinical and technical success, and considerable catch-up growth and pregnancy achievement. KEY POINTS: • Varicocele treatment using polidocanol foam sclerotherapy is a safe and effective procedure. • It is easily feasible in an outpatient setting. • The clinical and technical success rates are high. • It shows a high rate of patients' satisfaction and symptom resolution. • Postinterventional catch-up growth and pregnancy achievement are considerable.

Reduction of CT beam hardening artefacts of ethylene vinyl alcohol copolymer by variation of the tantalum content: evaluation in a standardized aortic endoleak phantom.

OBJECTIVES: Our aim was to develop an aortic stent graft phantom to simulate endoleak treatment and to find a tantalum content (TC) of ethylene-vinyl-alcohol-copolymer that causes fewer computed tomography (CT) beam hardening artefacts, but still allows for fluoroscopic visualization. METHODS: Ethylene-vinyl-alcohol-copolymer specimens of different TC (10-50 %, and 100 %) were injected in an aortic phantom bearing a stent graft and endoleak cavities with simulated re-perfusion. Fluoroscopic visibility of the ethylene-vinyl-alcohol-copolymer specimens was analyzed. In addition, six radiologists analyzed endoleak visibility, and artefact intensity of ethylene-vinyl-alcohol-copolymer in CT. RESULTS: Reduction of TC significantly decreased CT artefact intensity of ethylene-vinyl-alcohol-copolymer and increased visibility of endoleak re-perfusion (p < 0.000). It also significantly decreased fluoroscopic visibility of ethylene-vinyl-alcohol-copolymer (R = 0.883, p ≤ 0.01), and increased the active embolic volumes prior to visualization (Δ ≥ 40 µl). Ethylene-vinyl-alcohol-copolymer specimens with a TC of 45-50 % exhibited reasonable visibility, a low active embolic volume and a tolerable CT artefact intensity. CONCLUSIONS: The developed aortic stent graft phantom allows for a reproducible simulation of embolization of endoleaks. The data suggest a reduction of the TC of ethylene-vinyl-alcohol-copolymer to 45 -50 % of the original, to interfere less with diagnostic imaging in follow-up CT examinations, while still allowing for fluoroscopic visualization.

Typical exposure parameters, organ doses and effective doses for endovascular aortic aneurysm repair: Comparison of Monte Carlo simulations and direct measurements with an anthropomorphic phantom.

OBJECTIVES: Radiation exposure of patients during endovascular aneurysm repair (EVAR) procedures ranks in the upper sector of medical exposure. Thus, estimation of radiation doses achieved during EVAR is of great importance. MATERIAL AND METHODS: Organ doses (OD) and effective doses (ED) administered to 17 patients receiving EVAR were determined (1) from the exposure parameters by performing Monte Carlo simulations in mathematical phantoms and (2) by measurements with thermoluminescent dosimeters in a physical anthropomorphic phantom. RESULTS: The mean fluoroscopy time was 26 min, the mean dose area product was 24995 cGy cm2. The mean ED was 34.8 mSv, ODs up to 626 mSv were found. Whereas digital subtraction angiographies (DSA) and fluoroscopies each contributed about 50% to the cumulative ED, the ED rates of DSAs were found to be ten times higher than those of fluoroscopies. Doubling of the field size caused an ED rate enhancement up to a factor of 3. CONCLUSION: EVAR procedures cause high radiation exposure levels that exceed the values published thus far. As a consequence, (1) DSAs should be only performed when necessary and with a low image rate, (2) fluoroscopies should be kept as short as possible, and (3) field sizes should be minimized. KEY POINTS: • During endovascular aneurysm repair (EVAR) considerable patient doses are achieved. • For each EVAR procedure organ (OD) and effective (ED) doses were determined. • The mean ED was 34.8 mSv, the highest OD was 626 mSv. • Number of DSAs, fluoroscopy durations and field sizes should be minimized.

Complications of transbrachial arterial access for peripheral endovascular interventions.

PURPOSE: To prospectively assess current limitations and complication rates of the transbrachial access technique for endovascular treatment of peripheral vascular pathologies. METHODS: In total, 150 patients (112 men; mean age 66.3 ± 10.0 years) with arterial occlusive disease underwent endovascular therapy via a transbrachial access. Periprocedure data (sheath size, dose area product, fluoroscopy time, and procedure duration) were analyzed. Postprocedure complications of the puncture sites were categorized as minor (local hematoma, pseudoaneurysm, embolization, dissection, minor bleeding) and major (thrombotic occlusion, hematoma requiring surgery, major bleeding, nerve injury). RESULTS: The minor and major complication rates were 14.0% (n = 21) and 2.7% (n = 4). The most frequent major complication was thrombotic occlusion of the brachial artery requiring surgical treatment (3/150, 2%). There was only one temporary palsy of the median nerve and no stroke. Local hematoma (15, 10%), pseudoaneurysm (3, 2%), or a combination of both (3, 2%) dominated the minor complications. The average dose area product and fluoroscopy time were 12,752.1 ± 9524.5 cGy*cm(2) and 24.3 ± 18.4 minutes, respectively, though procedure duration was acceptable (121.8 ± 48.9 minutes). CONCLUSION: Complication rates of the transbrachial access for endovascular treatment of peripheral or visceral artery occlusive disease are tolerably low, making it a safe and an important alternative to the transfemoral access in selected cases, though the radiation exposure is rather high.

Endoleak and in-stent thrombus detection with CT angiography in a thoracic aortic aneurysm phantom at different tube energies using filtered back projection and iterative algorithms.

PURPOSE: To determine the lower limit of dose reduction with hybrid and fully iterative reconstruction algorithms in detection of endoleaks and in-stent thrombus of thoracic aorta with computed tomographic (CT) angiography by applying protocols with different tube energies and automated tube current modulation. MATERIALS AND METHODS: The calcification insert of an anthropomorphic cardiac phantom was replaced with an aortic aneurysm model containing a stent, simulated endoleaks, and an intraluminal thrombus. CT was performed at tube energies of 120, 100, and 80 kVp with incrementally increasing noise indexes (NIs) of 16, 25, 34, 43, 52, 61, and 70 and a 2.5-mm section thickness. NI directly controls radiation exposure; a higher NI allows for greater image noise and decreases radiation. Images were reconstructed with filtered back projection (FBP) and hybrid and fully iterative algorithms. Five radiologists independently analyzed lesion conspicuity to assess sensitivity and specificity. Mean attenuation (in Hounsfield units) and standard deviation were measured in the aorta to calculate signal-to-noise ratio (SNR). Attenuation and SNR of different protocols and algorithms were analyzed with analysis of variance or Welch test depending on data distribution. RESULTS: Both sensitivity and specificity were 100% for simulated lesions on images with 2.5-mm section thickness and an NI of 25 (3.45 mGy), 34 (1.83 mGy), or 43 (1.16 mGy) at 120 kVp; an NI of 34 (1.98 mGy), 43 (1.23 mGy), or 61 (0.61 mGy) at 100 kVp; and an NI of 43 (1.46 mGy) or 70 (0.54 mGy) at 80 kVp. SNR values showed similar results. With the fully iterative algorithm, mean attenuation of the aorta decreased significantly in reduced-dose protocols in comparison with control protocols at 100 kVp (311 HU at 16 NI vs 290 HU at 70 NI, P ≤ .0011) and 80 kVp (400 HU at 16 NI vs 369 HU at 70 NI, P ≤ .0007). CONCLUSION: Endoleaks and in-stent thrombus of thoracic aorta were detectable to 1.46 mGy (80 kVp) with FBP, 1.23 mGy (100 kVp) with the hybrid algorithm, and 0.54 mGy (80 kVp) with the fully iterative algorithm.

Treatment of type I endoleaks using transcatheter embolization with onyx.

PURPOSE: To report a single-center experience with transcatheter embolization of type I endoleaks using the liquid embolic agent Onyx, an ethylene vinyl alcohol copolymer. METHODS: Eight patients (4 men; mean age 74.8 years, range 63-86) with 10 type I endoleaks (6 abdominal and 4 thoracic) diagnosed 2 days to 9 years after endovascular repair were treated with Onyx embolization because cuff extension was precluded by an insufficient landing zone in 6 cases and an unsuitable aortic diameter in 2. Endoleaks were accessed with a 4-F diagnostic catheter and a coaxially introduced dimethylsulfoxide-compatible microcatheter. Onyx-34 was predominantly applied due to its high viscosity; patent side branches were coil embolized prior to Onyx delivery in 3 cases. RESULTS: Technical success of the procedure was achieved in all cases. The mean volume of Onyx used for abdominal endoleaks was 11.8 mL (range 3.0-25.5) and 19.4 mL (range 4.5-31.5) for thoracic endoleaks. The average duration of the procedure was 76.7 minutes (range 34.5-110.6), and the average radiation dose area product was 18.8 cGy*cm (2) (range 10.6-55.8). Reperfusion of the endoleak was detected in one case 2 days after the procedure. A second case showed an occluded endoleak but a small trace of contrast between the aortic wall and the stent-graft. Non-target embolization was not found in any case. Mean follow-up was 13.2 months (range 8-24). The mean reduction in diameters for thoracic aneurysms after 6 and 12 months was 0.4 and 0.9 cm, respectively, and 0.6 and 1.2 cm, respectively, for abdominal aneurysms. CONCLUSION: Transcatheter embolization of type I endoleaks using Onyx is a simple, safe, and sustainable treatment option with a high primary success rate for cases in which stent-graft extension is not possible. The benefit of additional coil embolization remains uncertain.

Filtered back projection, adaptive statistical iterative reconstruction, and a model-based iterative reconstruction in abdominal CT: an experimental clinical study.

PURPOSE: To compare objective and subjective image quality parameters of three image reconstruction algorithms of different generations at routine multidetector computed tomographic (CT) examinations of the abdomen. MATERIALS AND METHODS: This institutional review board-approved study included 22 consecutive patients (mean age, 56.1 years ± 15.8 [standard deviation]; mean weight, 79.1 kg ± 14.8) who underwent routine CT examinations of the abdomen. A low-contrast phantom was used for objective quality control. Raw data sets were reconstructed by using filtered back projection (FPB), adaptive statistical iterative reconstruction (ASIR), and a model-based iterative reconstruction (MBIR). Radiologists used a semiquantitative scale (-3 to +3) to rate subjective image quality and artifacts, comparing both FBP and MBIR images with ASIR images. The Wilcoxon test and the intraclass correlation coefficient were used to evaluate the data. Measurements of objective noise and CT numbers of soft tissue structures were compared with analysis of variance. RESULTS: The phantom study revealed an improved detectability of low-contrast targets for MBIR compared with ASIR or FBP. Subjective ratings showed higher image quality for MBIR, with better resolution (median value, 2; range, 1 to 3), lower noise (2; range, 1 to 3), and finer contours (2; range, 1 to 2) compared with ASIR (all P < .001). FBP performed inferiorly (0, range, -2 to 0]; -1 [range, -3 to 0]; 0 [range, -1 to 0], respectively; all, P < .001). Mean interobserver correlation was 0.9 for image perception and 0.7 for artifacts. Objective noise for FBP was 14%-68% higher and for MBIR was 18%-47% lower than that for ASIR (P < .001). CONCLUSION: The MBIR algorithm considerably improved objective and subjective image quality parameters of routine abdominal multidetector CT images compared with those of ASIR and FBP.