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1.
Radiologe ; 56(3): 233-9, 2016 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-26842999

RESUMO

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.


Assuntos
Arteriopatias Oclusivas/epidemiologia , Arteriopatias Oclusivas/cirurgia , Procedimentos Endovasculares/estatística & dados numéricos , Artéria Femoral/cirurgia , Artéria Poplítea/cirurgia , Stents/estatística & dados numéricos , Arteriopatias Oclusivas/diagnóstico , Análise de Falha de Equipamento , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Humanos , Prevalência , Desenho de Prótese , Reoperação/estatística & dados numéricos , Fatores de Risco , Resultado do Tratamento , Grau de Desobstrução Vascular
2.
Scand J Rheumatol ; 42(5): 379-82, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23713482

RESUMO

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.


Assuntos
Artrite Psoriásica/patologia , Articulações dos Dedos/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Edema/patologia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Sinovite/patologia , Tenossinovite/patologia , Adulto Jovem
3.
Radiologe ; 53(3): 230-45, 2013 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-23456042

RESUMO

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.


Assuntos
Cateterismo Periférico/efeitos adversos , Hemorragia/etiologia , Hemorragia/prevenção & controle , Hemostasia Cirúrgica/instrumentação , Hemostasia Cirúrgica/métodos , Doença Arterial Periférica/etiologia , Doença Arterial Periférica/prevenção & controle , Desenho de Equipamento , Humanos
4.
Unfallchirurgie (Heidelb) ; 126(5): 399-404, 2023 May.
Artigo em Alemão | MEDLINE | ID: mdl-35384465

RESUMO

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.


Assuntos
Cristalino , Procedimentos Ortopédicos , Ortopedia , Exposição à Radiação , Projetos Piloto , Exposição à Radiação/efeitos adversos , Cristalino/efeitos da radiação , Procedimentos Ortopédicos/efeitos adversos
5.
Radiologe ; 50(10): 879-86, 2010 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-20824423

RESUMO

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.


Assuntos
Angiografia Digital , Angiografia , Braço/irrigação sanguínea , Isquemia/diagnóstico por imagem , Vasculite/diagnóstico por imagem , Artrite Reumatoide/diagnóstico por imagem , Dedos/irrigação sanguínea , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Poliarterite Nodosa/diagnóstico por imagem , Doença de Raynaud/diagnóstico por imagem , Tromboangiite Obliterante/diagnóstico por imagem
6.
Radiologe ; 50(10): 872-8, 2010 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-20717644

RESUMO

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.


Assuntos
Angiografia , Angiografia Coronária , Trato Gastrointestinal/irrigação sanguínea , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Pulmão/irrigação sanguínea , Vasculite Sistêmica/diagnóstico , Tomografia Computadorizada por Raios X , Sistema Urogenital/irrigação sanguínea , Angiografia Digital , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Síndrome de Churg-Strauss/diagnóstico , Doença da Artéria Coronariana/diagnóstico , Granulomatose com Poliangiite , Humanos , Poliangiite Microscópica/diagnóstico , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Poliarterite Nodosa/diagnóstico
7.
Radiologe ; 50(10): 887-93, 2010 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-20717643

RESUMO

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.


Assuntos
Arteriopatias Oclusivas/terapia , Isquemia/terapia , Tromboangiite Obliterante/terapia , Adulto , Angiografia , Angioplastia , Arteriopatias Oclusivas/diagnóstico por imagem , Artérias/cirurgia , Terapia Combinada , Pé/irrigação sanguínea , Mãos/irrigação sanguínea , Heparina/uso terapêutico , Humanos , Isquemia/diagnóstico por imagem , Salvamento de Membro , Masculino , Microcirurgia , Prostaglandinas/uso terapêutico , Doença de Raynaud/diagnóstico por imagem , Doença de Raynaud/terapia , Fumar/efeitos adversos , Tromboangiite Obliterante/diagnóstico por imagem , Adulto Jovem
8.
Radiologe ; 50(10): 894-901, 2010 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-20799024

RESUMO

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.


Assuntos
Angioplastia , Aneurisma da Aorta Abdominal/cirurgia , Fibrose Retroperitoneal/cirurgia , Idoso , Aneurisma da Aorta Abdominal/diagnóstico , Endoleak/diagnóstico , Feminino , Seguimentos , Humanos , Hidronefrose/diagnóstico , Hidronefrose/cirurgia , Processamento de Imagem Assistida por Computador , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Fibrose Retroperitoneal/diagnóstico , Tomografia Computadorizada por Raios X
9.
Eur J Endocrinol ; 179(4): 261-267, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30299899

RESUMO

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.


Assuntos
Glândulas Suprarrenais/irrigação sanguínea , Coleta de Amostras Sanguíneas/métodos , Hiperaldosteronismo/diagnóstico , Doses de Radiação , Exposição à Radiação , Veias , Adulto , Idoso , Feminino , Fluoroscopia , Alemanha , Hospitais Universitários , Humanos , Hiperaldosteronismo/sangue , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Rofo ; 178(7): 698-705, 2006 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-16817123

RESUMO

PURPOSE: Assessment of low-contrast details in digital radiographs on different review displays (RD). MATERIALS AND METHODS: 20" flat screen panels (RD1: standard color LCD-TFT, RD2: monochrome LCD-TFT for radiological reading, RD1*: RD1 with optional image inversion; 205 cd/m (2) luminance, respectively) were evaluated. At 30 lx ambient lighting, 10 radiologists gradually increased the contrast (constant steps) for both a homogeneous picture and a cutout of a thorax radiography of n = 480 simulated nodules until they became recognizable. RESULTS: In the case of bright nodules on an anthropomorphic background, the use of image inversion produced significantly better results. No other significant differences were detected. CONCLUSION: Provided that the working environment is not bright, the results suggest that low-cost RD can be used for the recognition of low-contrast details in radiographies of the chest. Further studies including more display models are necessary. Among different ambient lighting and luminance settings, these studies should include a closer analysis of the special features of digital systems such as brightness/contrast adaptation, picture enlargement (zoom shot), and image inversion.


Assuntos
Aumento da Imagem/instrumentação , Intensificação de Imagem Radiográfica/instrumentação , Interface Usuário-Computador , Ecrans Intensificadores para Raios X , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Trials ; 17(1): 528, 2016 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-27793175

RESUMO

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.


Assuntos
Angioplastia com Balão/instrumentação , Fármacos Cardiovasculares/administração & dosagem , Materiais Revestidos Biocompatíveis , Artéria Femoral , Paclitaxel/administração & dosagem , Doença Arterial Periférica/terapia , Artéria Poplítea , Dispositivos de Acesso Vascular , Angiografia Digital , Angioplastia com Balão/efeitos adversos , Índice Tornozelo-Braço , Fármacos Cardiovasculares/efeitos adversos , Protocolos Clínicos , Angiografia por Tomografia Computadorizada , Constrição Patológica , Tolerância ao Exercício , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/fisiopatologia , Alemanha , Humanos , Masculino , Paclitaxel/efeitos adversos , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/fisiopatologia , Qualidade de Vida , Recuperação de Função Fisiológica , Recidiva , Projetos de Pesquisa , Fatores de Risco , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Grau de Desobstrução Vascular , Caminhada
13.
Rofo ; 177(11): 1491-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16302129

RESUMO

PURPOSE: To evaluate image quality and anatomical detail depiction in dose-reduced digital plain chest radiograms using a new needle screen storage phosphor (NIP) in comparison to full dose conventional powder screen storage phosphor (PIP) images. MATERIALS AND METHODS: 24 supine chest radiograms were obtained with PIP at standard dose and compared to follow-up studies of the same patients obtained with NIP with dose reduced to 50 % of the PIP dose (all imaging systems: AGFA-Gevaert, Mortsel, Belgium). In both systems identical versions of post-processing software supplied by the manufacturer were used with matched parameters. Six independent readers blinded to both modality and dose evaluated the images for depiction and differentiation of defined anatomical regions (peripheral lung parenchyma, central lung parenchyma, hilum, heart, diaphragm, upper mediastinum, and bone). All NIP images were compared to the corresponding PIP images using a five-point scale (- 2, clearly inferior to + 2, clearly superior). Overall image quality was rated for each PIP and NIP image separately (1, not usable to 5, excellent). RESULTS: PIP and dose reduced NIP images were rated equivalent. Mean image noise impression was only slightly higher on NIP images. Mean image quality for NIP showed no significant differences (p > 0.05, Mann-Whitney U test). CONCLUSION: With the use of the new needle structured storage phosphors in chest radiography, dose reduction of up to 50 % is possible without detracting from image quality or detail depiction. Especially in patients with multiple follow-up studies the overall dose can be decreased significantly.


Assuntos
Intensificação de Imagem Radiográfica , Radiografia Torácica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Proteção Radiológica , Radiografia Torácica/instrumentação , Decúbito Dorsal , Avaliação da Tecnologia Biomédica , Ecrans Intensificadores para Raios X
14.
Rofo ; 177(2): 250-7, 2005 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-15666234

RESUMO

PURPOSE: Recommendations for archiving digital radiological image data based on the comparison of retrieval times for different PACS archive levels. MATERIALS AND METHODS: For a large PACS installation (Agfa Impax, Release 4.1), image retrieval times for radiological standard examinations (chest radiographs with 2, MRI with 250, CT with 100 and 1000 images; n = 120, each) from hard disk array, magneto-optical disk (MOD), and magnetic tape archives (TAPE) were examined in high and low network traffic load. RESULTS: Even large CT examinations (1000 images) were available from hard disk arrays within 4.0 +/- 0.8 s, smaller studies within 1.8 +/- 0.3 s. Radiographic image retrieval from MOD (30 +/- 4.7 s) was more then 50 % faster than from TAPE. For typical cross-sectional studies, the velocity gain amounted to 19 %. For both technologies, no significant difference was found for large CT examinations (651 +/- 144 s). For high and low network traffic load scenarios, image retrieval times from hard disk, MOD, and TAPE archives increased by 87 %, 7 %, and 22 %, respectively. CONCLUSION: Hard disk arrays are specifically suited as departmental intermediate storage media because they allow fast access to current and previous examinations within a short time. Performance properties enable both MOD and TAPE systems to serve as long-term archives. However, MOD archives are less flexible in the expansion of storage capacity and at present the medium costs per memory unit are about 2 - 3 times higher than for tape archives. The use of existing MOD-archives may be adequate as intermediate archives. For new PACS installations or system expansions, however, it is recommended to combine a sufficiently large local data memory (RAID) with data storage on tape archives outside the radiological unit that can be used by other departments as well. Future development of hard disk prices will show whether archiving for the whole data retention period may be handled by RAID systems. In any case, prefetching problems and waiting periods for demanded pre-studies would not occur any more.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Humanos , Armazenamento e Recuperação da Informação/métodos , Reagentes de Laboratório/normas , Sensibilidade e Especificidade , Fatores de Tempo , Carga de Trabalho
16.
Rofo ; 187(10): 915-23, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26085177

RESUMO

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.


Assuntos
Acrilatos , Cateterismo Cardíaco/efeitos adversos , Chumbo , Exposição Ocupacional/prevenção & controle , Exposição à Radiação/prevenção & controle , Proteção Radiológica/instrumentação , Desenho de Equipamento , Humanos , Imagens de Fantasmas , Doses de Radiação , Radiometria/métodos , Espalhamento de Radiação
17.
Nuklearmedizin ; 43(6): 195-202, 2004 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-15586215

RESUMO

UNLABELLED: Besides conventional x-ray, 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 a newly developed low field MRI with proven methods such as conventional x-ray and 3P-Sz. PATIENTS, METHODS: 42 patients were studied using a one days protocol with 3P-Sz, MRI, and x-ray of the hands with yearly follow up examinations. 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 summarised findings interpreted by a rheumatologist in consideration of the Ritchie articular index as gold-standard. RESULTS: 24/42 patients presented with clinical symptoms of initial changes by rheumatoid arthritis. Conventional x-ray revealed in 20/24 patients within the correct diagnosis in the study period. On the other hand 3P-Sz and low field MRI concordantly showed all 24 patients with initial changes due to RA. Time of detection showed variations with a tendency to later findings by conventional x-ray. CONCLUSIONS: In the diagnostic work up of initial changes conventional x-ray should be the first choice in imaging. Our findings suggest that MRI represents an equally sensitive method for the diagnosis of initial changes due to RA in the region of the hands as compared to the 3P-Sz. The limitation of the low field MRI is the small field of view, so we prefer 3P-Sz or high field MRI in the diagnosis of patients with suspected RA.


Assuntos
Artrite Reumatoide/diagnóstico , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/fisiopatologia , Osso e Ossos/diagnóstico por imagem , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Radiografia , Cintilografia , Estudos Retrospectivos
18.
Nuklearmedizin ; 41(3): 135-42, 2002 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-12109033

RESUMO

UNLABELLED: Besides 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 the newly developed low field MRI with the proven methods X-rays and 3P-Sz. METHODS: 65 patients (47f, 18m; 20-86 yrs) were studied on a one day protocol with 3P-Sz (550 MBq Tc-99m DPD), MRI and X-rays of the hands. Images were visually analysed by two blinded nuclear medicine physicians and radiologists and classified as a) RA-typical, b) inflammatory, non-RA-typical and c) non inflammatory changes. All methods were compared to 3P-Sz as golden standard. RESULTS: In comparison to 3P-Sz, low field MRI presents with almost equal sensitivity and specificity in rheumatoid-typical and inflammatory changes. Conventional X-rays revealed in arthritis-typical changes as well as in inflammatory changes a significantly lower sensitivity and also a lower negative predictive value while specificity equals the one of MRI. Quantitative analysis of 3P-Sz using ROI-technique unveiled significantly higher values in patients with rheumatoid arthritis than in those with no inflammatory changes. CONCLUSION: MRI represents an equally sensitive method in the initial diagnosis of rheumatoid-typical and inflammatory changes in the region of the hands as compared to the 3P-Sz. Besides the basic diagnosis with conventional X-rays, 3P-Sz is still the recommended method of choice to evaluate the whole body when RA is suspected. Additionally, quantitative analysis of the 3P-Sz using the ROI technique in the region of the hands reveals statistically significant results and should therefore be taken into account in the assessment of inflammatory changes.


Assuntos
Artrite Reumatoide/diagnóstico , Osso e Ossos/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Reumatoide/diagnóstico por imagem , Feminino , Mãos , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Cintilografia , Reprodutibilidade dos Testes
19.
J Cardiovasc Surg (Torino) ; 54(5): 553-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24002383

RESUMO

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.


Assuntos
Angioplastia com Balão/instrumentação , Extremidade Inferior/irrigação sanguínea , Doença Arterial Periférica/terapia , Dispositivos de Acesso Vascular , Adulto , Idoso , Angioplastia com Balão/efeitos adversos , Berlim , Doença Crônica , Constrição Patológica , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
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