[Radiation exposure of the eye lens in orthopedics and trauma surgery : A pilot study]. / Strahlenbelastung der Augenlinse in O&U : Eine Pilotstudie.

BACKGROUND: On 27 June 2017 the Act on new regulation of the law for the protection against the harmful effects of ionizing radiation was passed. One of the main innovations in daily surgical practice in the now legally stipulated provisions is the lowering of the eye lens dose to 20 mSv/year (§§ 78, 212 Radiation Protection Act, StrlSchG). MATERIAL AND METHODS: To estimate the level of exposure of the eye lens to ionizing radiation that is to be expected in the course of surgical interventions, the dose that surgeons receive during surgery was determined. For this, the radiation exposure adjacent to the eye lens was measured using a forehead dosimeter while performing surgical interventions over a period of 8 weeks in 2 different operating rooms. RESULTS: As a result, a mean estimated eye lens radiation dose Hp (3) of 190 µSv could be determined during the 2­month study period. Thus, the estimated cumulative radiation dose in 1 year of approximately 1.2 mSv was significantly below the threshold of 20 mSv/year. CONCLUSION: By complying with the common radiation protection measures in the context of operative interventions in orthopedics and trauma surgery, the legal limit value of 20 mSv/year is generally not expected to be exceeded.

Radiation exposure of adrenal vein sampling: a German Multicenter Study

Objective: Adrenal vein sampling (AVS) represents the current diagnostic standard for subtype differentiation in primary aldosteronism (PA). However, AVS has its drawbacks. It is invasive, expensive, requires an experienced interventional radiologist and comes with radiation exposure. However, exact radiation exposure of patients undergoing AVS has never been examined. Design and Methods: We retrospectively analyzed radiation exposure of 656 AVS performed between 1999 and 2017 at four university hospitals. The primary outcomes were dose area product (DAP) and fluoroscopy time (FT). Consecutively the effective dose (ED) was approximately calculated. Results: Median DAP was found to be 32.5 Gy*cm2 (0.3­3181) and FT 18 min (0.3­184). The calculated ED was 6.4 mSv (0.1­636). Remarkably, values between participating centers highly varied: Median DAP ranged from 16 to 147 Gy*cm2, FT from 16 to 27 min, and ED from 3.2 to 29 mSv. As main reason for this variation, differences regarding AVS protocols between centers could be identified, such as number of sampling locations, frames per second and the use of digital subtraction angiographies. Conclusions: This first systematic assessment of radiation exposure in AVS not only shows fairly high values for patients, but also states notable differences among the centers. Thus, we not only recommend taking into account the risk of radiation exposure, when referring patients to undergo AVS, but also to establish improved standard operating procedures to prevent unnecessary radiation exposure.

The effectiveness of the paclitaxel-coated Luminor® balloon catheter versus an uncoated balloon catheter in superficial femoral and popliteal arteries in preventing vessel restenosis or reocclusion: study protocol for a randomized controlled trial.

BACKGROUND: The aim of this investigator-initiated trial is to evaluate the safety and efficacy of the novel Luminor® paclitaxel-coated drug-eluting balloon (DEB) catheter (iVascular, S.L.U., Barcelona, Spain) in inhibiting restenosis and in ensuring long-term vascular patency. METHODS/DESIGN: This is a multicenter randomized controlled trial to evaluate the Luminor® paclitaxel-coated DEB catheter for stenotic or occlusive lesions (length ≤15 cm) in the superficial femoral artery (SFA) and the popliteal artery (PA) up to the P1 segment compared to the noncoated, plain old balloon angioplasty (POBA) catheter. In total 172 subjects will be treated with either the DEB catheter or the POBA catheter in 11 German study centers in a 1:1 randomization study design. The primary endpoint is late lumen loss (LLL) at 6 months. Secondary endpoints are patency rate, target lesion/vessel revascularization, quality of life (assessed with the Walking Impairment Questionnaire (WIQ) and the EQ-5D), change of Rutherford stage and ankle-brachial index, major and minor amputation rate at the index limb, number of dropouts and all-cause mortality. DISCUSSION: EffPac represents a randomized controlled trial that will provide evidence on the effectiveness of the Luminor® paclitaxel-coated DEB catheter for the reduction of restenosis compared to the POBA catheter for the SFA and the PA. The results of EffPac will allow direct comparison to other already-completed RCTs applying paclitaxel-coated DEBs from different manufacturers with different coating technologies in the same target vessel. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02540018 , registered on 17 August 2015. Protocol version: CIP Version Final04, 11 February 2016. EUDAMED No: CIV-15-03-013204.

[Stent-assisted recanalization of femoropopliteal arterial occlusive disease. Influence of stent design on patency rates]. / Stentgestützte Rekanalisation der femoropoplitealen arteriellen Verschlusskrankheit. Einfluss des Stentdesigns auf die Offenheitsrate.

BACKGROUND: Despite enormous technical progress the results of endovascular treatment of the femoropopliteal vasculature are unsatisfactory and its role is still controversially discussed. In the past decade numerous new stent designs have come onto the market but it is unclear whether they have benefits with respect to patency rates. OBJECTIVES: Comparison of published data on patency rates and target lesion revascularization rates after use of different stent designs in the femoropopliteal vasculature. MATERIAL AND METHODS: Analysis of 25 published studies and registries from 2006 to 2015 for classical open-cell stents, interwoven stents and partially or fully covered stents. RESULTS AND CONCLUSION: The published data are heterogeneous and comparative studies for different stent designs are completely missing. Over the past decade the patency rates after femoropopliteal stenting could be improved. According to available data stenting of short lesions < 5 cm does not show any benefit compared to isolated balloon angioplasty. Primary stenting is now recommended for intermediate and longer lesions > 6.4 cm. Due to the heterogeneity of published data a clear benefit for a specific stent design is not obvious; however, data for interwoven stents are promising and show a tendency towards improved patency, at least for certain lesions. Randomized controlled comparative trials are needed to confirm this result.

A New Design of a Lead-Acrylic Shield for Staff Dose Reduction in Radial and Femoral Access Coronary Catheterization.

PURPOSE: Today's standard radiation protection during coronary angiography and percutaneous coronary interventions is the combined use of lead acrylic shields and table-mounted lower body protection. Ambient dose measurements, however, have shown that these protection devices need improvement. MATERIALS AND METHODS: Using an anthropomorphic physical phantom, various scenarios were investigated with respect to personnel exposure: a) enlarging the shield b) adding a flexible protective curtain to the bottom side of the shield, and c) application of radioprotective patient drapes. For visualization of the dose reduction effect, Monte Carlo simulations were performed. RESULTS: The flexible curtain in contact with the patient's body reduces the ambient dose rate at the operator's position by up to (87.5% ± 7.1) compared to the situation with the bare shield. The use of both the flexible curtain and the patient drape reduces the ambient dose rate by up to (90.8% ± 7). Similar results were achieved for the assisting personnel when they were positioned next to the operator. In addition, the enlarged shield provides better protection of the head region of tall operators. CONCLUSION: Adding a flexible protective curtain to the bottom side of the shield can protect operators from high doses, especially for body parts which are not protected by lead aprons, e.g. head, and eye lenses. This may be important with respect to lower dose limits for eye lenses in future. The protective effect in real-life working conditions is still being evaluated in an ongoing clinical study. KEY POINTS: Lead acrylic shields need improvement for a better protection of head and eye lenses. An additional flexible lead curtain at the bottom of the shield can considerably reduce the operator dose. Using the additional lead curtain, lighter protection clothing can be worn. Special eye protection may be no longer needed in most applications.

Successful revascularization of chronic total occlusion of lower extremity arteries: a wire only and bail out use of re-entry device approach.

AIM: The management of progressive peripheral artery disease experienced a vast change in paradigms over the last decades for the benefit of minimal invasive therapy as a first-line strategy. With the constant development of new devices, materials and dedicated access strategies, more complex lesions can be managed but the limitations to successfully treat chronic total occlusions are still the challenge to re-enter the true lumen. The aim of this retrospective study was to investigate, if a "wire only" strategy leads to an acceptable success rate in a mixed cohort of CTO lesions and to what extend re-entry devices are used. METHODS: We retrospectively analyzed patients treated at the Vascular Center Berlin between 2011 and 2013 with chronic total occlusion out of a prospective conducted database (Endovascular MILestones - EMIL) for demographics, risk factors, co-morbidities, technical success rates, lesion characteristics and use of guidewires as well as re-entry systems. A total of 128 patients with 146 lesions, which represent a subgroup of all the cases performed in our center, following a predefined treatment algorithm for chronic total occlusions (CTOs), have been analyzed. RESULTS: We achieved a technical success in 133 (91.1%) of all cases following a "wire only" strategy. Out of 13 (8.9%) CTOs with technical failure in 7 (53.9%) CTOs a re-entry device (Off-Road®) with a 100% technical success has been used. In 91.1% of chronic total occlusion lesions the use of 2 wires only (88.7%) led to a successful recanalization. A "wire only" strategy followed by the use of a re-entry device as a bail out strategy, led to a total of 140 (96%) lesions to be successfully recanalized. CONCLUSION: In more than 90% of all cases with chronic total occlusion of peripheral lower extremity arteries, endovascular intervention has been successful following a "wire only" strategy. When deciding to use a re-entry device, in case of a failure of a proper wire re-entry at the reconstitution point, a technical success rate of 100% was achieved. Therefore following a strict wire algorithm and considering the use of a re-entry system as a bail out strategy will lead to a successful minimal invasive management of chronic total occlusion in nearly 100% of the cases with TASC II A - D lesions.

Feasibility and reproducibility of the PsAMRIS-H score for psoriatic arthritis in low-field-strength dedicated extremity magnetic resonance imaging.

OBJECTIVES: The psoriatic arthritis magnetic resonance imaging scoring system (PsAMRIS-H) for the evaluation of inflammatory and destructive changes in PsA hands was validated on 0.6-T scanners. The applicability of the PsAMRIS-H on a low-field MRI system as a well-accepted, low-cost imaging modality was evaluated. METHOD: In 65 consecutive patients (31 males, median age 52 years), 73 scans on a 0.2-T dedicated extremity MRI system were obtained for evaluation of PsA. Images were scored for synovitis, tenosynovitis, periarticular enhancement, bone erosion, bone oedema, and proliferation, and the PsAMRIS-H score was calculated. The intraclass correlation coefficient (ICC) was calculated and the paired t-test conducted. RESULTS: Intra-reader reliability for the total PsAMRIS-H score was good, with an ICC of 0.81 and 0.77 for readers 1 and 2, respectively, and inter-reader agreement was moderate (0.57 for each reader). However, the PsAMRIS-H score differed significantly between the two readers (22 vs. 31; p < 0.05). When individual components of the PsAMRIS were evaluated, intra- and inter-reader agreement was poor to moderate, especially for tenosynovitis and periarticular inflammation. CONCLUSIONS: Low-field 0.2-T MRI is capable of quantifying the PsAMRIS-H with good intra-reader reproducibility. However, low signal-to-noise ratio (SNR), low spatial resolution, and system artefacts limit the application of the PsAMRIS-H, leading to low inter- and intra-reader agreement for individual features.

[Arterial closure devices. What device for which clinical situation?]. / Arterielle Verschlusssysteme. Welches wofür?

CLINICAL/METHODICAL ISSUE: Access site complications after endovascular catheterization sometimes require open surgery and negatively impair safety, patient comfort and reimbursement. Increasing numbers of procedures and patients with multiple anticoagulants as well as cost pressure explain the demand for an immediate and stable access site closure. STANDARD RADIOLOGICAL METHODS: Manual compression followed by compression bandage and bed rest for 4-24 h is still the gold standard but is unable to prevent access site complications in all cases. METHODICAL INNOVATIONS: Arterial vascular closure devices allow immediate and stable closure of the puncture channel either by suture or by implantation of occluding foreign bodies or gluing fluids. PERFORMANCE: The safety has been proven in several clinical trials. The main advantage lies in closing large lumen access sites without surgery and in patients treated with multiple anticoagulants as well as in outpatient procedures. ACHIEVEMENTS: They have become a valuable supplement to the interventional arsenal. PRACTICAL RECOMMENDATIONS: The physician, however, has to decide between different systems and mechanisms with respect to patient constitution, selected access vessel and level of calcification and diameter. Furthermore, all systems require a defined training prior the first use.

[Angiographic diagnosis of acral circulatory disorders of the upper extremities]. / Angiographische Diagnostik akraler Durchblutungsstörungen an der oberen Extremität.

Acral ischemic lesions rarely affect the upper extremities. While in the lower limbs atherosclerosis is responsible for the majority of lesions, vasculitis and autoimmune diseases play an important role in the pathogenesis of ischemic lesions of the upper limbs. A considerable number of acral circulatory disorders present with Raynaud's phenomenon and often without associated necrosis. Raynaud's phenomenon is mainly idiopathic but may also be secondary to underlying conditions, such as autoimmune diseases and vasculitis. Because of its high spatial resolution and the often discrete morphological findings digital subtraction angiography (DSA) is still an important diagnostic method in the radiological evaluation of acral circulatory disorders of the hand. Angiographic features of vasculitis are not strictly pathognomonic but certain morphologic DSA findings are very typical and may allow for a radiologic diagnosis. For instance, atherosclerosis results in irregular contours of vessel walls in DSA in contrast to autoimmune diseases and vasculitis, which are usually characterized by smooth vessel walls and optional vasospasm, the latter being especially typical for thromboangiitis obliterans and scleroderma. In thromboangiitis obliterans occlusions of the distal hand arteries, corkscrew collateral vessels and subsequent development of fine collateral networks are typical findings. Abrupt or filiform occlusions of distal finger arteries with sparse collateralization and symmetric affection of both hands are suggestive of scleroderma. Disseminated segmental ectasis and stenosis as well as microaneurysms (63% of all patients) are very common in patients with panarteriitis nodosa.

[Inflammatory aortic aneurysms: Single center experiences with endovascular repair of inflammatory abdominal aortic aneurysms]. / Inflammatorische Aortenaneurysmen: Single-center-Erfahrungen nach endovaskulärer Ausschaltung inflammatorischer Bauchaortenaneurysmen.

We report our single center experience of renal function, hydronephrosis and changes in perianeurysmal fibrosis (PAF) after endovascular repair (EVAR) of inflammatory abdominal aortic aneurysms (IAAA). A total of 6 patients were treated for IAAA with EVAR and the technical success was 100%. During the follow-up period 5 patients showed regression of PAF and 1 patient showed minor progression of PAF on computed tomography scans. In 2 patients hydronephrosis was regressive postoperatively but no patients died within 30 days. There were no secondary complications to report and no secondary intervention was necessary. In the long-term course one patient exhibited complete regression of PAF.In appropriate cases EVAR is a safe method for aneurysm repair for IAAA. In patients with acute inflammation or hydronephrosis individual treatment concepts are required.

[Therapy of peripheral vessel stenosis and occlusion in patients with thromboangiitis obliterans]. / Therapie peripherer Gefäßstenosen und -verschlüsse bei Thromboangiitis obliterans.

Vasculitis consists of a group of diseases characterized by an inflammatory process of the vessel wall. There is a wide variation in symptoms and almost any organ or tissue can be affected. Thromboangiitis obliterans (TAO; also known as Buerger's disease) is a special form of vasculitis with recurring inflammation and thrombosis of small and medium size arteries and veins of the hands and feet. To date the etiology still remains unclear but there is a strong association with the use of tobacco products. Ulcerations and gangrene of the extremities are common complications often resulting in the need for amputation of the extremity involved. Treatment of TAO includes both surgical and non-surgical methods but there is still no agreement concerning the optimal treatment strategy. In this contribution the advantages and disadvantages of different treatment options will be addressed and representative cases will be discussed.

[Vasculitis in the trunk: Imaging patterns of typical organ manifestations due to primary vasculitis of small and medium sized vessels]. / Vaskulitiden am Körperstamm: Bildgebende Diagnostik typischer Organmanifestationen der primären Vaskulitiden mittelgroßer und kleiner Gefäße.

Vasculitis of small and medium sized vessels mostly affects several organ systems and causes unspecific symptoms. The trunk, lungs, heart and the gastrointestinal and urogenital tracts are most frequently involved. Due to an unclear clinical picture imaging is part and parcel of diagnostics. The knowledge of typical and rare imaging patterns as well as knowledge of the correct imaging method is crucial for classification. Projection radiography is still the gold standard for imaging of the lungs. Using computed tomography discrete ground-glass pattern opacities, nodules and consolidations can be depicted. In the abdomen computed tomography and magnetic resonance imaging can depict swelling of the intestinal wall. Digital subtraction angiography may contribute to further differentiation and reveal microaneurysms in cases of polyarteriitis nodosa.

[Peripheral arterial disease. Diagnosis and therapy according to current guidelines]. / Arterielle Verschlusskrankheit. Leitliniengerechte Diagnostik und Therapie.

Guidelines conduce to establish consistent standards of therapy and contribute to the orientation and safeguard of the attending physician. Peripheral arterial disease (PAD) may be classified according to its stage as intermittent claudication, chronic critical limb ischemia or acute limb ischemia. Since these diseases are common and life-threatening, current guidelines are of major interest for the attending physician, not least because of forensic reasons. This overview describes the current principles of diagnosis and therapy as well as recent developments in peripheral endovascular intervention. Current national and international guidelines, particularly the Transatlantic Intersociety Consensus (TASC), were taken into account.

[Imaging in the early diagnosis of changes in the hand of patients suffering from rheumatoid arthritis. Is ultrasound a true alternative for low-field magnetic resonance scanning, 3-phase bone scintigraphy and conventional x-rays?]. / Bildgebende Verfahren in der Frühdiagnostik rheumatischer Veränderungen der Hände. Ist die Sonographie eine echte Alternative zur Niederfeld-MRT, 3-Phasen-Skelettszintigraphie und Projektionsradiographie?

PURPOSE: Besides the use of conventional x-rays in the diagnostic work-up of initial changes in patients suffering from rheumatoid arthritis (RA), 3-phase bone scintigraphy (3P-Sz) is as well established as magnetic resonance imaging (MRI). The aim of this study was to compare the diagnostic value of ultrasound of the hands with proven methods such as conventional x-rays, low-field MRI and 3P-Sz. METHODS: A total of 30 patients were studied using a 1 day protocol with ultrasound, 3P-Sz, MRI and x-ray of the hands. Images were visually assessed by two blinded nuclear medicine physicians and radiologists and classified as RA typical and non-RA typical changes. All methods were compared to the summarized findings interpreted by a rheumatologist after 2 years. RESULTS: Of the 30 patients, 19 presented with clinical symptoms of initial changes due to rheumatoid arthritis. Ultrasound revealed 14/19 patients with the correct diagnosis. Conventional x-rays indicated 11/19 patients, while 3P-Sz (100%) and low-field MRI (95%) showed high sensitivity. It was possible to differentiate between inflammation and inconspicuous findings. CONCLUSIONS: An experienced examiner can use ultrasound effectively for the initial diagnosis of RA. Based on its low cost, ultrasound is a valid alternative to conventional x-rays.

[Comparison of C-arm CT and standard imaging in osteosyntheses of fractured distal radius specimens]. / Ein Vergleich von C-Bogen-CT und Standardbildgebung an Osteosynthesen frakturierter Präparate des distalen Radius.

BACKGROUND: The purpose of this study was to evaluate the value of C-arm CT imaging of the distal radius with standard patient positioning in intraoperative assessment of plate osteosynthesis. MATERIALS AND METHODS: Four complete distal radius specimens from human cadavers were fractured (type C), and internal fixation with palmar plates (stainless steel) was then carried out in each. On the basis of C-arm fluoroscopy, radiography and C-arm CT (Siremobil Iso-C3D, scans with forearm bones positioned parallel to the z-axis), 19 observers subsequently evaluated the positions of screws near the joint and any steps within the joint, after which the bones were surgically exposed and the imaging results checked against direct visual observations. RESULTS: No statistically significant differences were detected either between the modalities or between the evaluator groups. CONCLUSION: With standard patient positioning, the performance of C-arm CT was equivalent to and not better than that of current standard procedures, i.e. intraoperative fluoroscopy and postoperative radiography. Further studies should examine whether this holds true in clinical practice with representative patient collectives when titanium implants are used and/or optimized patient positioning is practised.

[Chronic critical ischemia of the lower leg: pretherapeutic imaging and methods for revascularization]. / Die chronische kritische Unterschenkelischämie: prätherapeutische Diagnostik, Methoden der Revaskularisation.

Each year 1-2% of patients with peripheral arterial occlusive disease (pAOD) develop critical limb ischemia (CLI), characterized by rest pain and peripheral ulcer or gangrene. This aggravation of the disease is accompanied by an increase of the 1-year mortality rate up to 25% and a similarly increased frequency of major amputation. We can choose between conservative, endovascular, and surgical procedures for an adequate therapy of the underlying vascular stenoses or occlusions. Yet, clear therapeutic recommendations only exist for suprapopliteal lesions. However, in a number of cases, especially in diabetics, target lesions have an infrapopliteal location. Since endovascular procedures have undergone significant improvement in the last few years, the following review discusses methods for infrapopliteal revascularization taking into consideration the newest publications on this topic.