[New developements in endovascular infrarenal aortic aneurysm treatment]. / Aktuelle Neuerungen bei der endovaskulären Versorgung infrarenaler Aortenaneurysmen.

CLINICAL/METHODICAL ISSUE: New technical developments in endovascular aortic repair (EVAR) have broadened the range of patients eligible for minimally invasive aneurysm treatment. Optimization of delivery sheaths and catheters by considerable downsizing of diameters, increase of pushability and stability combined with flexibility are important parameters. PERFORMANCE: Especially patients characterized by small and tortuous iliac access vessels can nowadays be treated by EVAR. Ease and effectiveness of applicability guarantee safety and quality improvement, which results in better treatment of patients. Progress in stent-graft design with integrated options for repositioning, active positioning and aneurysm sealing facilitate treatment of angulated vessel segments or hitherto unsuitable sealing zones. PRACTICAL RECOMMENDATIONS: Interventionalists have to be familiar with all available stent-graft materials and techniques. Profound knowledge helps to choose the best material for a patient's individual anatomy, confident application and long-term satisfactory results.

Transarterial embolization (TAE) as add-on to percutaneous radiofrequency ablation (RFA) for the treatment of renal tumors: Review of the literature, overview of state-of-the-art embolization materials and further perspective of advanced image-guided tumor ablation.

Percutaneous radiofrequency ablation (RFA) for the treatment of stage I renal cell carcinoma has recently gained significant attention as the now available long-term and controlled data demonstrate that RFA can result in disease-free and cancer-specific survival comparable with partial and/or radical nephrectomy. In the non-controlled single center trials, however, the rates of treatment failure vary. Operator experience and ablation technique may explain some of the different outcomes. In the controlled trials, a major limitation is the lack of adequate randomization. In case reports, original series and overview articles, transarterial embolization (TAE) before percutaneous RFA was promising to increase tumor control and to reduce complications. The purpose of this study was to systematically review the literature on TAE as add-on to percutaneous RFA for renal tumors. Specific data regarding technique, tumor and patient characteristics as well as technical, clinical and oncologic outcomes have been analyzed. Additionally, an overview of state-of-the-art embolization materials and the radiological perspective of advanced image-guided tumor ablation (TA) will be discussed. In conclusion, TAE as add-on to percutaneous RFA is feasible and very effective and safe for the treatment of T1a tumors in difficult locations and T1b tumors. Advanced radiological techniques and technologies such as microwave ablation, innovative embolization materials and software-based solutions are now available, or will be available in the near future, to reduce the limitations of bland RFA. Clinical implementation is extremely important for performing image-guided TA as a highly standardized effective procedure even in the most challenging cases of localized renal tumors.

The Use of Iliac Side Branch Devices in Patients with Aortoiliac Aneurysm.

PURPOSE: The aim of this study was to evaluate the technical feasibility and short-time patency rate of iliac side branch devices based on the authors' institution's experience. MATERIALS AND METHODS: Data of 17 patients (all men) with an aortoiliac aneurysm (median age 72.5 years) who underwent endovascular repair between October 2013 and June 2015 (20 months) at our institution was analyzed retrospectively. Primary endpoint was primary technical success, defined as adequate implantation of the iliac branch device with patency of the hypogastric side branch without the need of further re-interventions within 30 days. Mean follow-up was 8.2 ±â€Š5.4 months. RESULTS: Eighteen iliac side branch devices were implanted with a branch patency of 100 % and a primary technical success rate of 94.4 % (n = 17). Perioperative 30 days mortality was 0 %. The mean diameter of treated abdominal aorta and common iliac artery was 41 ±â€Š14 and 30 ±â€Š8 mm. In one case partial dislocation of the iliac side branch device occurred due to severe kinking of iliac arteries with development of an iliac endoleak type Ib that had to be treated in a second intervention. Three patients (15 %) showed an endoleak type II from the inferior mesenteric artery without the need of re-intervention. After three months one patient suffered from subtotal thrombotic occlusion of the bridging stent that was successfully resolved through intra-arterial fibrinolytic therapy and additional stent graft implantation. CONCLUSION: Summarized, implantation of iliac side branch devices is a feasible technique with favourable short-term results in patients with aortoiliac aneurysm. KEY POINTS: • Implantation of iliac side branch devices is a feasible technique.• Distinguish short-term results of side branch endografting in patients with aortoiliac aneurysm.• Carefully patient selection is necessary to avoid complications and re-interventions. Citation Format: • Maus V, Kurz P, Sommer CM et al. The Use of Iliac Side Branch Devices in Patients with Aortoiliac Aneurysm.. Fortschr Röntgenstr 2016; 188: 746 - 752.

A wire transposition technique for recanalization of chronic complex central venous occlusions.

PURPOSE: A minimal-invasive interventional technique for recanalization of complex chronic central venous total occlusions is described to overcome difficulties in case of failure of common approaches. METHOD: We present a patient with a central venous occlusion that caused severe venous congestion of her upper extremity and significant impairment of her forearm hemodialysis shunt. Since the usual transbrachial and transfemoral attempts for recanalization of occluded right subclavian, brachiocephalic, superior vena cava, and proximal internal jugular veins (IJV) failed, the approach was changed to a transjugular access. Only the IJV and subclavian vein occlusions were passed from transjugular. RESULTS: The key procedure was the switch of a jugular-brachial wire to a femoral-brachial setting. The wire transposition was achieved by snaring the looped stiff end of the jugular-brachial wire outside the jugular sheath from the opposite femoral access. CONCLUSION: Different approaches should be considered for the recanalization of challenging central venous occlusions. After failed attempts via common access sites, a guidewire transposition maneuver using a combined approach may be particularly helpful for safe and effective endovascular treatment of complex situations.

Evaluation of a Gadolinium-Based Nanoparticle (AGuIX) for Contrast-Enhanced MRI of the Liver in a Rat Model of Hepatic Colorectal Cancer Metastases at 9.4 Tesla.

PURPOSE: The aim of this study was to compare a Gd-based nanoparticle (AGuIX) with a standard extracellular Gd-based contrast agent (Gd-DOTA) for MRI at 9.4 T in rats with hepatic colorectal cancer metastases. MATERIALS AND METHODS: 12 rats with hepatic metastases were subjected to MRI using a 9.4 T animal scanner. T1w self-gated FLASH sequences (TR/TE = 45/2.5 ms, alpha = 45°, TA = 1: 23 min, FOV = 5.12 × 5.12 cm(2), matrix = 256 × 256) were acquired before and at 10 time points after contrast injection. Each animal received 0.1 mmol/kg BW Gd-DOTA i.v. 2 days later AGuIX was applied at 0.01 mmol/kg BW (representing equal Gd doses). The SNR of normal liver (SNRliver), hyper- and hypoenhancing parts of tumors (SNRtumor, hyperenh/SNRtumor, hypoenhanc), erector spinae muscle (SNRmuscle), CNR and lesion enhancement (LE) were calculated based on ROI measurements. RESULTS: Mean SNRliver (Gd-DOTA: 14.6 +/- 0.7; AGuIX: 28.2+/- 2.6, p < 0.001), SNRtumor, hyperenhanc (Gd-DOTA: 18.6 +/- 1.2; AGuIX: 29.6 +/- 2.8, p < 0.001), SNRtumor, hypoenhanc (Gd-DOTA: 12.0 +/- 0.7; AGuIX: 15.4 +/- 0.7, p < 0.001), SNRmuscle (Gd-DOTA: 12.3 +/- 0.3; AGuIX: 14.0 +/- 0.7, p < 0.001), mean CNR (Gd-DOTA: -2.5 +/- 0.2; AGuIX: -7.5 +/- 1.0, p < 0.001) and LE (Gd-DOTA: 3.8 +/- 0.7; AGuIX: 14.9 +/- 2.8, p = 0.001) were significantly higher using AGuIX. Regardless of the larger molecular size, AGuIX demonstrates an early peak enhancement followed by a continuous washout. CONCLUSION: AGuIX provides better enhancement at 9.4 T compared to Gd-DOTA for equal doses of applied Gd. This is based on the molecule structure and the subsequent increased interaction with protons leading to a higher relaxivity. AGuIX potentially ameliorates the conspicuity of focal liver lesions and may improve the sensitivity in diagnostic imaging of malignant hepatic tumors. KEY POINTS: AGuIX provides superior enhancement as compared to the extracellular compound Gd-DOTA at 9.4 T. AGuIX may improve the detection and diagnostic sensitivity of malignant focal liver lesions. The small size of AGuIX allows for fast renal clearance and prevents undesirable accumulation in the body.

Recurrent High-Flow Arterio-Venous Malformation of the Thyroid Gland.

BACKGROUND: Vascular malformations and hemangiomas of the thyroid gland are rare disorders. The first case of a patient with recurrent high-flow arterio-venous malformation of the right thyroid gland involving the right endolarynx is presented. PATIENT FINDINGS: In June 2013, a 42-year-old female patient presented to the surgical department with recurrent hoarseness and a soft, vibrating mass on the right side of her neck. In 1993, she underwent right subtotal hemithyroidectomy with embolization on the day before surgery for a high-flow arterio-venous malformation of the thyroid gland. Diagnostic work-up in 2013 demonstrated a complex recurrent high-flow arterio-venous malformation on the right side of her neck involving the endolarynx. Full function of the right vocal fold could not be ascertained. The lesion was embolized again and excised the following day. Intraoperative gross bleeding and scar tissue prevented visualization and monitoring of the recurrent laryngeal nerve. Gross bleeding was also noted on hemithyroidectomy after embolization in 1993. No therapy was needed for the endolaryngeal part of the lesion. Histology showed large arterio-venous malformations with thyroid tissue. She remains well without signs of recurrence 18 month later but with a definitive voice handicap. SUMMARY: This is the first report of a recurrent high-flow arterio-venous malformation originally developing from the right thyroid gland involving the right endolarynx. Counseling, diagnostic, and therapeutic work-up of the patient was possible only with an interdisciplinary team. The endolaryngeal part of the hemangioma dried out after embolization and completion hemithyroidectomy. Her hoarseness has greatly improved but a definitive voice handicap remains. CONCLUSION: High-flow arterio-venous malformations of the thyroid gland are a rare disease, and recurrent lesions have not been reported. Interdisciplinary management of these patients is mandatory due to the complex nature of the underlying pathology. Recurrence might develop after long free intervals.

[A giant non-parasitic liver cyst as a prominent epigastric mass in an obese patient]. / Riesige nicht-parasitäre Leberzyste als äusserlich sichtbare epigastrische Vorwölbung bei einem adipösen Patienten.

HISTORY AND ADMISSION FINDINGS: A 62-year-old, obese male patient was referred because of an increasing prominent epigastric mass and bloated feeling. An epigastric hernial defect was clinically excluded. INVESTIGATIONS: Abdominal imaging by ultrasound and CT-scan demonstrated a giant liver cyst in the left lobe of 20 cm in diameter with a displacement of the stomach. Endoscopy showed an external compression of the stomach. Cystic echinococcosis was excluded by serology. TREATMENT AND COURSE: Laparoscopic deroofing of the cyst resulted in immediate freedom of symptoms. The further course was uneventful. The patient was discharged one day after the operation. CONCLUSION: Liver cysts may become symptomatic by intestinal compression syndromes or - occasionally - as a prominent abdominal mass. Laparoscopic deroofing is the golden standard of symptomatic non parasitic liver cysts and is associated with a good clinical outcome.

[Percutaneous mechanical atherectomy for treatment of peripheral arterial occlusive disease]. / Perkutane mechanische Atherektomie zur Behandlung der peripheren arteriellen Verschlusskrankheit.

Peripheral arterial occlusive disease (PAOD) is still an extremely important politico-economic disease. Diverse treatment procedures exist but the pillars of therapy are changes in lifestyle, such as nicotine abstinence and walking exercise as well as drug therapy. Further therapy options are considered after conventional procedures have been exhausted. These further options consist of improvement of the blood supply by surgical or minimally invasive procedures. The latter therapy options include balloon dilatation and stenting as the most widely used techniques. More recent techniques also used are cryoplasty, laser angioplasty, drug-coated stents or balloons as well as brachytherapy or atherectomy, whereby this list makes no claims to completeness. The multitude of different treatment methods emphatically underlines the fact that no resounding success can be achieved with one single method. The long-term results of both balloon dilatation and stenting techniques show a need for improvement, which elicited the search for additional methods for the treatment of PAOD. Atherectomy represents such an alternative method for treatment of PAOD. Basically, the term atherectomy means the removal of atheroma tissue. For percutaneous atherectomy, in contrast to surgical procedures, it is not necessary to create surgically access to the vessel but accomplishes the atherectomy by means of dedicated systems via a minimally invasive access. There are two basic forms of mechanical atherectomy: directional and rotational systems.

[MR imaging and MR angiography of the aorta]. / Magnetresonanztomographie und -angiographie der Aorta.

When a diseased aorta is to be imaged, the clinical picture and the urgency determine which of the various procedures available is or are used. One of the more recent techniques applied is conventional MR -imaging, and especially contrast-enhanced MR angiography (CE-MRA), which is a noninvasive technique and allows for the combination of conventional imaging, acquisition of physiological parameters and 3D-angiography. In this article technical and clinical aspects of the use of CE-MRA in different diseases affecting the aorta are discussed. Topics covered include congenital malformations of the aorta, acquired disease, and inflammatory conditions.

[Magnetic resonance tomography and arthrography of the hip joint]. / Magnetresonanztomographie und -arthrographie des Hüftgelenks.

Plain film radiographs represent the imaging of choice for the initial evaluation of pathologies of the hip. However, many lesions of the joint itself and surrounding soft tissues are often not visualized by conventional radiographs. Magnetic resonance imaging (MRI) demonstrates most of these pathologies with high sensitivity and specificity. For further assessment of intra-articular lesions such as labral tears, hyaline cartilage lesions, rupture of the ligamentum teres, and loose bodies, direct MR arthrography after intra-articular administration of contrast medium may be indicated. This article summarizes the technical aspects and the most important indications for MRI and MR arthrography of the hip in correlation with typical imaging findings of the most frequent pathologies.

[Quality of life assessment after surgery for diverticulitis - a follow-up study]. / Lebensqualität nach chirurgischer Therapie einer Divertikulitis - Ergebnisse im Follow-up -

BACKGROUND: Laparoscopic sigmoid resection is a well established procedure for surgical treatment of benign colorectal diseases. The aim of the present study was to assess the longterm quality of life of patients who underwent laparoscopic sigmoid resection for sigmoid diverticulitis. Differences in health related life quality to the open-conventional approach were evaluated in a matched pair analysis (age, gender, Hinchey-Stage, Type of Surgery) using a validated quality of life instrument. METHODS: A total of 45 matched pairs (laparoscopic/open) operated for diverticulitis at stage I-IIa (Hinchey classification) were included in this study. The quality of life was measured with the Short-Form-36-Health Survey (SF-36), a standardized questionnaire with 8 scales and 36 items. The follow-up period was at least 2 years (mean 62.2 months). RESULTS: Pair members (n = 45) operated via laparoscopic or open approach for Hinchey I-IIa diverticulitis were of the same sex (21 female/24 male pairs) and age at time of surgery (range: lap.: 53.5-66 years; open: 53.5-67 years). Mean follow-up periods for patients operated laparoscopically and with open procedure were 2 (range: 1-3) and 7 (range: 5-9) years, respectively. The SF-36 scale scores for both groups appeared high and only slightly below a validated norm population. This represents a high quality of life after open as well as laparoscopic surgery for sigmadiverticulitis. No significant differences were apparent between the 45 matched-pairs. Pairs 65 years old or older presented no significantly different score values compared to those younger than 65 years. CONCLUSIONS: The long-term follow-up data in this age and sex matched pair analysis showed favorable results after open as well as laparoscopic surgery for sigmadiverticulitis. No statistically significant differences were observed between the two surgical techniques. Self-reports by the patient concerning his or her health condition, recovery and quality of life following any surgical procedure are needed to assess valid outcome data of new surgical treatments including a critical evaluation of all its benefits and burdens.

Decreasing estrogen in nonpregnant women lowers uterine myometrial type I nitric oxide synthase protein expression.

OBJECTIVE: Our purpose was to study the effect of estrogen on myometrial nitric oxide synthase. STUDY DESIGN: Twenty-four women were randomly assigned to treatment with gonadotropin-releasing hormone agonist or placebo for 8 weeks before hysterectomy, at which time samples of myometrium were collected and the serum levels of estrogen, nitrate, and nitrite measured. Myometrial nitric oxide synthase was measured with the arginine-citrulline assay. The levels of endothelial nitric oxide synthase and neuronal nitric oxide synthase were determined by Western blot analysis. RESULTS: Myometrial nitric oxide synthase was 88% calcium dependent but only partially calmodulin dependent. Women treated with gonadotropin-releasing hormone agonist had postmenopausal levels of estradiol and had significantly lower levels of myometrial neuronal nitric oxide synthase than those in the control group. Total, endothelial, and inducible nitric oxide synthase levels in the myometrium were unchanged, as were serum nitrite and nitrate levels. CONCLUSION: Neuronal nitric oxide synthase is regulated in the myometrium by estrogen. Myometrial nitric oxide synthase is not all calmodulin dependent; this may represent the activity of a novel nitric oxide synthase isoform.

Effects of estrogen on nitric oxide biosynthesis and vasorelaxant activity in sheep uterine and renal arteries in vitro.

OBJECTIVES: Our purpose was to determine whether estrogen alters the relaxation responses to bradykinin and superoxide dismutase of the uterine and renal arteries and to determine the role of nitric oxide in that response. STUDY DESIGN: Ten nulliparous, ovariectomized nonpregnant sheep received either estradiol-17beta or vehicle solution. In vitro studies evaluating vasorelaxation were done with either bradykinin or superoxide dismutase. The nitric oxide inhibitor nomega-nitro-L-arginine methyl ester was used to determine the role of nitric oxide in this process. Nitric oxide synthase activity was assessed by measuring citrulline generation. RESULTS: We found a dose dependency of relaxation to bradykinin and superoxide dismutase. Estrogen enhanced this response in uterine arteries. Estrogen increased citrulline generation in uterine but not renal arteries. Nomega-nitro-L-arginine methyl ester blocked relaxation responses and citrulline generation in both arteries. CONCLUSION: In nonpregnant sheep we found that nitric oxide release and nitric oxide synthase activity is enhanced by estrogen in the uterine arteries but not in the renal arteries. Increases in nitric oxide synthase activity may be important in the hyperemic response of the uterus during estrus.

Lack of effect of fetal administration of cocaine on maternal and fetal plasma adrenocorticotropin, cortisol and lactate concentrations at 127-138 days gestational age.

Few in vivo studies have attempted to characterize the effects of cocaine on the maternal and fetal pituitary-adrenal axis during pregnancy. We, therefore, administered cocaine (2 mg.kg-1) intravenously to 6 fetal sheep at 127-138 days of gestation. There was a transient reduction in fetal arterial pO2 with a concomitant increase in pCO2 and a prolonged fall in pH (p less than 0.05) following cocaine injection. No changes were seen in maternal pO2, pCO2 or pH. Maternal plasma adrenocorticotropin, cortisol and lactate were not affected by fetal administration of cocaine. Although there was a tendency for fetal plasma adrenocorticotropin, cortisol and lactate to rise after administering cocaine, the increases were not statistically significant. Previous studies have shown that cocaine administration to the ewe at a similar stage of pregnancy results in increased fetal plasma adrenocorticotropin concentrations. The results of the present study indicate that cocaine administration to the fetus compromises fetal gas exchange and acid base balance, but the effects on the fetal pituitary-adrenal axis are less pronounced than after maternal administration of cocaine.

Lack of effect of fetal administration of cocaine on maternal and fetal plasma adrenocorticotropin, cortisol and lactate concentrations at 127-138 days gestational age.

Few in vivo studies have been done to characterize the effects of cocaine on the maternal and fetal pituitary-adrenal axis during pregnancy. We, therefore, administered cocaine (2 mg.kg-1) intravenously to 6 fetal sheep at 127-138 days of gestation. There was a transient reduction in fetal arterial pO2 with a concomitant increase in pCO2 and a prolonged fall in pH (p less than 0.05) following cocaine injection. No changes were seen in maternal pO2, pCO2 or pH. Maternal adrenocorticotropin (ACTH), cortisol and lactate were not affected by fetal administration of cocaine. Although there was a tendency for fetal plasma ACTH, cortisol and lactate to rise after administering cocaine, the increases were not statistically significant. Previous studies have shown that cocaine administration to the ewe at a similar stage of pregnancy results in increased fetal plasma ACTH concentrations. The results of the present study indicate that cocaine administration to the fetus compromises fetal gas exchange and acid-base balance but the effects on the fetal pituitary-adrenal axis are less pronounced than after maternal administration of cocaine.

Endocrine changes during 48 hours of food withdrawal in the pregnant rhesus monkey in the last third of gestation.

We studied the hormonal responses in four pregnant rhesus monkeys between 112 and 149 days gestation. After 2 days, during which the monkeys were fed ad libitum, their food was withdrawn at 1500 h for 48 h while allowing free access to water. The food then was returned, and the animals were studied for a further 2 days. The mean maternal whole blood glucose concentration significantly decreased, and plasma cortisol and dehydroepiandrosterone sulfate (DHEAS) concentrations significantly increased within 30 h of food withdrawal (P less than 0.05). The maternal plasma estradiol concentration increased significantly at 1000 h on the second day of food withdrawal (P less than 0.05), whereas the plasma progesterone concentration did not change. The maternal blood glucose and plasma cortisol, DHEAS and estradiol concentrations returned to baseline by the second day of food replacement. We conclude that the stress of hypoglycemia and/or the attendant inability to eat, together or separately, stimulate maternal adrenal glucocorticoid and androgen secretion during the period of food withdrawal. The increased maternal DHEAS and perhaps other adrenal androgen concentrations result in increased maternal estrogen production.

Effect of food withdrawal on arterial blood glucose and plasma 13,14-dihydro-15-keto-prostaglandin F2 alpha concentrations and nocturnal myometrial electromyographic activity in the pregnant rhesus monkey in the last third of gestation: a model for preterm labor?

Pregnant rhesus monkeys were studied between 109 and 149 days of gestation. Food withdrawal for 48 hours (with free access to water) was accompanied by a decrease in maternal whole blood glucose concentration and an increased maternal arterial plasma 13,14-dihydro-15-keto-prostaglandin F2 alpha concentration. On successive nights of the 48-hour period of food withdrawal, there was an increase in the frequency of myometrial contractions as recorded by uterine electromyogram. In the period after food was returned, blood glucose, arterial 13,14-dihydro-15-keto-prostaglandin F2 alpha concentration, and contraction frequency returned to baseline. Because food withdrawal results in the appearance of the nocturnal contraction pattern seen at term, we suggest that this experimental paradigm may be used as a model for preterm labor.