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1.
Radiologe ; 59(8): 700-709, 2019 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-31187161

RESUMO

BACKGROUND: Imaging-based analysis of articular cartilage and its defects as well as the radiologist have to live up to the more and more specific clinical questions arising from increasing experience with cartilage-dedicated therapies. MATERIALS AND METHODS: Based on the currently available literature and experience from clinical routine, imaging findings relevant for lesion analysis will be summarized and illustrated by specific pathologies. RESULTS: Local aspects and topographic distribution of bone marrow edema pattern (BMEP), careful analysis of the cartilage surface and of the subchondral plate as well as the patient's clinical and biomechanical context are essential for image analysis. Formal grading is helpful to communicate imaging findings, but in itself is not sufficient for a comprehensive analysis. Assessing the stability of a lesion is important for therapy planning. Imaging is helpful to this end, but can be challenging and requires consideration of the arthroscopic and histologic perspective especially when dealing with juvenile osteochondral lesions. DISCUSSION: In order to maximize the therapeutic and prognostic relevance of findings from cartilage imaging, radiologists need to be sensitive to-often very subtle-imaging clues but at the same time we need to be aware of the limitations of our methods.


Assuntos
Doenças da Medula Óssea , Cartilagem Articular , Edema/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Edema/fisiopatologia , Humanos , Imageamento por Ressonância Magnética
2.
Radiologe ; 59(8): 692-699, 2019 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-31240354

RESUMO

BACKGROUND: In order to answer clinical therapy-oriented questions, reliable and consistent depiction of articular cartilage across technical platforms is necessary. MATERIALS AND METHODS: Technical standards and developments in cartilage imaging are summarized based on current literature and experience from clinical daily routine. RESULTS: Clinical questions that need to be answered relate to cross-sectional extent, depth, differentiating cartilaginous from bony components of a lesion and to the lesion's location within the compartment. If present, displaced fragments, concomitant meniscal, ligamentous and/or degenerative lesions should be identified. To date, magnetic resonance imaging (MRI) is the workhorse of cartilage imaging and is largely based on moderately T2-weighted and also proton-density (PD)-weighted fat-suppressed turbo-spin-echo sequences. Direct MR- and CT-arthrography are the gold standard to evaluate thin cartilage layers. Recent advances in coil and MR sequence design, increased availability of 3T-MR scanners and more and more sophisticated acceleration techniques allow for better spatial resolution and more robust image contrast at acceptable scan times. DISCUSSION: As abundant as current developments in clinical routine cartilage imaging may be, the radiologist must carefully select the approach best suited to answering the clinical questions.


Assuntos
Doenças das Cartilagens , Cartilagem Articular , Artrografia , Doenças das Cartilagens/diagnóstico por imagem , Doenças das Cartilagens/fisiopatologia , Cartilagem Articular/diagnóstico por imagem , Estudos Transversais , Humanos , Imageamento por Ressonância Magnética
3.
Z Rheumatol ; 77(2): 127-134, 2018 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-28752409

RESUMO

OBJECTIVE: To retrospectively assess and analyze the clinical efficacy and safety of off-label interleukin-1 (IL-1) blockade with anakinra during pregnancy of patients with familial Mediterranean fever (FMF). METHODS: Retrospective analysis of clinical and laboratory parameters making use of an electronic database system. Detailed descriptions of the genotype and phenotype of FMF are given and the course of the pregnancy and fetal development are reported. RESULTS: The data of three patients and a total of four pregnancies under treatedment with anakinra were analyzed. All patients were of Mediterranean origin, fulfilled the Tel Hashomer criteria for diagnosis of FMF and had a confirmed mutation in the MEFV gene. In all patients, treatment with anakinra was initiated due to an insufficient treatment response to colchicine. Anakinra led to a rapid response in all patients. In three pregnancies anakinra treatment was continued during the whole pregnancy, while in one pregnancy anakinra was started in the second trimester because of uncontrolled FMF activity. Fetal development was normal in all pregnancies. In two patients the fetuses were carried to term, while in one patient a primary cesarean section was carried out in week 33 because of an increased risk for complications. All children showed an unremarkable early childhood development without any signs of an existing disease. CONCLUSION: The data of our retrospective analysis suggest that IL-1-blockade by anakinra is an effective and safe treatment in pregnant women suffering from FMF, which can reliably prevent disease flares. In the four pregnancies presented the use of anakinra did not result in impaired fetal and (early) childhood development.


Assuntos
Febre Familiar do Mediterrâneo , Proteína Antagonista do Receptor de Interleucina 1 , Complicações Infecciosas na Gravidez , Cesárea , Criança , Febre Familiar do Mediterrâneo/tratamento farmacológico , Feminino , Humanos , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Interleucina-1 , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Pirina , Estudos Retrospectivos
6.
Epidemiol Infect ; 144(15): 3170-3175, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27311302

RESUMO

Accurate data on the incidence of West Nile virus (WNV) disease are important for directing public health education and control activities. The objective of this project was to assess the underdiagnosis of WNV neuroinvasive disease through laboratory testing of patients with suspected viral meningitis or encephalitis at selected hospitals serving WNV-endemic regions in three states. Of the 279 patients with cerebrospinal fluid (CSF) specimens tested for WNV immunoglobulin M (IgM) antibodies, 258 (92%) were negative, 19 (7%) were positive, and two (1%) had equivocal results. Overall, 63% (12/19) of patients with WNV IgM-positive CSF had WNV IgM testing ordered by their attending physician. Seven (37%) cases would not have been identified as probable WNV infections without the further testing conducted through this project. These findings indicate that over a third of WNV infections in patients with clinically compatible neurological illness might be undiagnosed due to either lack of testing or inappropriate testing, leading to substantial underestimates of WNV neuroinvasive disease burden. Efforts should be made to educate healthcare providers and laboratorians about the local epidemiology of arboviral diseases and the optimal tests to be used in different clinical situations.


Assuntos
Encefalite Viral/epidemiologia , Meningite Viral/epidemiologia , Febre do Nilo Ocidental/epidemiologia , Vírus do Nilo Ocidental/isolamento & purificação , Adolescente , Adulto , Idoso , Anticorpos Antivirais/líquido cefalorraquidiano , Arizona/epidemiologia , California/epidemiologia , Criança , Encefalite Viral/líquido cefalorraquidiano , Encefalite Viral/virologia , Feminino , Hospitais , Humanos , Incidência , Masculino , Meningite Viral/líquido cefalorraquidiano , Meningite Viral/virologia , Pessoa de Meia-Idade , Minnesota/epidemiologia , Vigilância da População , Febre do Nilo Ocidental/líquido cefalorraquidiano , Febre do Nilo Ocidental/complicações , Adulto Jovem
7.
Eur Radiol ; 25(6): 1731-41, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25595640

RESUMO

OBJECTIVES: To implement a novel voxel-based technique to identify statistically significant local cartilage deformation and analyze in-vivo topographic knee cartilage deformation patterns using a voxel-based thickness map approach for high-flexion postures. METHODS: Sagittal 3T 3D-T1w-FLASH-WE-sequences of 10 healthy knees were acquired before and immediately after loading (kneeling/squatting/heel sitting/knee bends). After cartilage segmentation, 3D-reconstruction and 3D-registration, colour-coded deformation maps were generated by voxel-based subtraction of loaded from unloaded datasets to visualize cartilage thickness changes in all knee compartments. RESULTS: Compression areas were found bifocal at the peripheral medial/caudolateral patella, both posterior femoral condyles and both anterior/central tibiae. Local cartilage thickening were found adjacent to the compression areas. Significant local strain ranged from +13 to -15 %. Changes were most pronounced after squatting, least after knee bends. Shape and location of deformation areas varied slightly with the loading paradigm, but followed a similar pattern consistent between different individuals. CONCLUSIONS: Voxel-based deformation maps identify individual in-vivo load-specific and posture-associated strain distribution in the articular cartilage. The data facilitate understanding individual knee loading properties and contribute to improve biomechanical 3 models. They lay a base to investigate the relationship between cartilage degeneration patterns in common osteoarthritis and areas at risk of cartilage wear due to mechanical loading in work-related activities. KEY POINTS: • 3D MRI helps differentiate true knee-cartilage deformation from random measurement error • 3D MRI maps depict in vivo topographic distribution of cartilage deformation after loading • 3D MRI maps depict in vivo intensity of cartilage deformation after loading • Locating cartilage contact areas might aid differentiating common and work-related osteoarthritis.


Assuntos
Cartilagem Articular/fisiologia , Exercício Físico/fisiologia , Articulação do Joelho/fisiologia , Adulto , Feminino , Fêmur/fisiologia , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico , Osteoartrite do Joelho/fisiopatologia , Patela/fisiologia , Postura , Amplitude de Movimento Articular/fisiologia , Tíbia/fisiologia , Suporte de Carga/fisiologia
8.
Int J Colorectal Dis ; 30(1): 97-103, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25367184

RESUMO

PURPOSE: Off-midline procedures seem to be the best method of primary wound closure after excision of a pilonidal sinus. Primary wound closure with a Limberg flap was compared to secondary wound healing. METHODS: From January 2006 to July 2012, 102 patients with given informed consent (mean age 28 years, men 81%) who had excision of a pilonidal sinus in three hospitals in Switzerland were randomised to group L (Limberg flap, n = 51) or to group E (excision only, n = 51). Primary endpoint was duration of incapacity for work. Follow-up was at 3 weeks and at 1 year postoperative (95% follow-up). RESULTS: Both groups were comparable with regard to patient characteristics. The median (range) operation time was 60 (30-80) min in group L vs. 30 (10-75) min in group E (p < 0.001). No significant differences were found in postoperative pain and painkiller intake; pain, percentage of patients at work and overall satisfaction at 3 weeks postoperative; and overall duration of incapacity for work and overall satisfaction at 1-year follow-up. The complication rate was 49% in group L vs. 12% in group E (p < 0.001). Complications in group L were seroma (6%), wound dehiscence (45%), skin necrosis (10%), hematoma (6%), infection (4%) and recurrent disease (13%). Complications in group E were recurrent disease (6%) and wound healing disorder (6%). CONCLUSIONS: After excision of a pilonidal sinus, primary wound closure with a Limberg flap has no advantage over secondary wound healing. The main reason for this conclusion is the relatively high complication rate of primary wound closure with a Limberg flap.


Assuntos
Seio Pilonidal/cirurgia , Região Sacrococcígea/cirurgia , Retalhos Cirúrgicos/efeitos adversos , Cicatrização , Adolescente , Adulto , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Dor Pós-Operatória/etiologia , Satisfação do Paciente , Recidiva , Resultado do Tratamento , Adulto Jovem
9.
Hernia ; 19(2): 307-11, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24615504

RESUMO

PURPOSE: High pressure peaks might be a risk factor for the development of abdominal hernia. The course of abdominal pressure during extubation remains unclear. This preliminary study assessed the impact of two established extubation techniques. METHODS: Twenty-four consecutive patients suffering from abdominal wall hernia with the indication for surgical treatment were included. Twelve patients were extubated directly after the intravenous anaesthesia was stopped, before they had spontaneous breathing (deep extubation). The other 12 were extubated after they had spontaneous breathing (awake extubation). Intra-abdominal pressure (IAP) was measured via bladder catheter continuously. RESULTS: The highest value during extubation as well as the main increase in IAP was significantly lower in patients who underwent deep extubation (p < 0.001). CONCLUSIONS: Therefore, this extubation technique might improve the outcome of hernia repair.


Assuntos
Extubação/efeitos adversos , Hérnia Abdominal/etiologia , Hipertensão Intra-Abdominal/etiologia , Adulto , Idoso , Extubação/métodos , Feminino , Hérnia Abdominal/fisiopatologia , Humanos , Hipertensão Intra-Abdominal/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pressão , Fatores de Risco
10.
Artigo em Alemão | MEDLINE | ID: mdl-25323210

RESUMO

OBJECTIVE: The aim of our study was to implement and test an imaging protocol for the detection and evaluation of standardised cartilage defects using high-field magnetic resonance imaging (MRI) and to determine its limitations. MATERIAL AND METHOD: A total of 84 cartilage defects were created in the femoral condyles of euthanized dogs with a minimum body mass of 25 kg. The cartilage defects had a depth of 0.3 to 1.0 mm and a diameter of 1 to 5 mm. T1-FLASH-3D-WE-sequences with an isotropic voxel size of 0.5 x 0.5 x 0.5 mm and an anisotropic voxel size of 0.3 x 0.3 x 0.8 mm were used. In addition to quantitative evaluation of the cartilage defects, the sig- nal intensities, signal-to-noise ratios and contrast-to-noise ratios of the cartilage were determined. Of special interest were the limita- tions in identifying and delineating the standardised cartilage defects. RESULTS: With the anisotropic voxel size, more cartilage defects were detectable. Our results demonstrated that cartilage defects as small as 3.0 mm in diameter and 0.4 mm in depth were reliably detected using anisotropic settings. Cartilage defects below this size were not reliably detected. CONCLUSION AND CLINICAL RELEVANCE: We found that for optimal delineation of the joint cartilage and associated defects, a higher in-plane resolution with a larger slice thickness should be used, corresponding to the anisotropic settings employed in this study. For the delineation of larger cartilage defects, both the anisotropic and isotropic imaging methods can be used.


Assuntos
Doenças das Cartilagens/veterinária , Cartilagem Articular/patologia , Doenças do Cão/diagnóstico , Doenças do Cão/patologia , Imageamento por Ressonância Magnética/veterinária , Joelho de Quadrúpedes/patologia , Animais , Doenças das Cartilagens/diagnóstico , Doenças das Cartilagens/patologia , Cães , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos
11.
Transpl Infect Dis ; 16(6): 988-92, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25179757

RESUMO

In both conditions, post-transplant lymphoproliferative disorder (PTLD) and hemophagocytic lymphohistiocytosis (HLH), infection with Epstein-Barr virus (EBV) is a key mechanism: almost all PTLD in allogeneic stem cell transplantation (alloSCT) is caused by EBV-related neoplastic lymphoproliferation, and secondary HLH is most frequently triggered by EBV infection. Therefore, concomitant EBV-driven PTLD and HLH early after alloSCT require an approach to eliminate EBV and balance immune activation simultaneously. We report on a patient who developed simultaneous PTLD and signs of HLH on day 64 after alloSCT. Treatment was comprised of stopping cyclosporine, short-course dexamethasone, and 3 courses of rituximab. The patient showed full recovery and complete remission of lymphadenopathy. This result indicates that immediate reduction in EBV-carrying B cells by rituximab, suppression of general inflammation, and parallel support of reconstitution of long-term T-cell function, might be an appropriate therapeutic approach in this rare situation.


Assuntos
Infecções por Vírus Epstein-Barr/complicações , Linfo-Histiocitose Hemofagocítica/complicações , Transtornos Linfoproliferativos/virologia , Transplante de Células-Tronco/efeitos adversos , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais Murinos/administração & dosagem , Anticorpos Monoclonais Murinos/uso terapêutico , Dexametasona/administração & dosagem , Dexametasona/uso terapêutico , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/uso terapêutico , Linfo-Histiocitose Hemofagocítica/patologia , Masculino , Rituximab , Adulto Jovem
12.
Unfallchirurg ; 117(3): 235-41, 2014 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-23179821

RESUMO

BACKGROUND: Over the course of the past two decades autologous chondrocyte implantation (ACI) has become an important surgical technique for treating large cartilage defects. The original method using a periostal flap has been improved by using cell-seeded scaffolds for implantation, the matrix-based autologous chondrocyte implantation (mb-ACI) procedure. MATERIAL AND METHODS: Uniform nationwide guidelines for post-ACI rehabilitation do not exist. A survey was conducted among the members of the clinical tissue regeneration study group concerning the current rehabilitation protocols and the members of the study group published recommendations for postoperative rehabilitation and treatment after ACI based on the results of this survey. RESULTS: There was agreement on fundamentals concerning a location-specific rehabilitation protocol (femoral condyle vs. patellofemoral joint). With regard to weight bearing and range of motion a variety of different protocols exist. Similar to this total agreement on the role of magnetic resonance imaging (MRI) for postsurgical care was found but again a great variety of different protocols exist. CONCLUSIONS: This manuscript summarizes the recommendations of the members of the German clinical tissue regeneration study group on postsurgical rehabilitation and MRI assessment after ACI (level IVb/EBM).


Assuntos
Doenças das Cartilagens/terapia , Transplante de Células/reabilitação , Transplante de Células/normas , Condrócitos/transplante , Ortopedia/normas , Guias de Prática Clínica como Assunto , Reabilitação/normas , Doenças das Cartilagens/patologia , Alemanha , Transplante Autólogo/reabilitação , Transplante Autólogo/normas
13.
Clin Infect Dis ; 57(8): 1114-28, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23861361

RESUMO

BACKGROUND: Encephalitis continues to result in substantial morbidity and mortality worldwide. Advances in diagnosis and management have been limited, in part, by a lack of consensus on case definitions, standardized diagnostic approaches, and priorities for research. METHODS: In March 2012, the International Encephalitis Consortium, a committee begun in 2010 with members worldwide, held a meeting in Atlanta to discuss recent advances in encephalitis and to set priorities for future study. RESULTS: We present a consensus document that proposes a standardized case definition and diagnostic guidelines for evaluation of adults and children with suspected encephalitis. In addition, areas of research priority, including host genetics and selected emerging infections, are discussed. CONCLUSIONS: We anticipate that this document, representing a synthesis of our discussions and supported by literature, will serve as a practical aid to clinicians evaluating patients with suspected encephalitis and will identify key areas and approaches to advance our knowledge of encephalitis.


Assuntos
Algoritmos , Técnicas e Procedimentos Diagnósticos/normas , Encefalite/diagnóstico , Adulto , Criança , Consenso , Humanos
14.
Clin Infect Dis ; 56(6): 825-32, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23196954

RESUMO

BACKGROUND: Encephalitis is a severe neurological syndrome with devastating consequences. Despite extensive testing, the etiology often remains unknown. Involvement of the thalamus or basal ganglia (T/BG) occurs in a subset of patients with encephalitis and may be an important etiological clue. In order to improve diagnosis of T/BG patients, we reviewed this subgroup within the California Encephalitis Project (CEP). METHODS: Data from T/BG cases enrolled in CEP were retrospectively reviewed. Cases were stratified by age and grouped by etiological classification: infectious, postinfectious, and noninfectious. Neuroimaging reports were examined and compared between etiologies. RESULTS: T/BG neuroimaging abnormalities were reported in 6% of 3236 CEP cases. An etiology was found in 76%: 37% infectious, 16% postinfectious, and 23% noninfectious. The most frequently identified infectious agents were respiratory viruses, accounting for 31%, predominantly in children. Other infections more common in the T/BG group included Creutzfeldt-Jakob disease, arbovirus, and Mycobacterium tuberculosis. Infectious and postinfectious cases had higher median cerebrospinal fluid white blood cell count than noninfectious etiologies. Notably, T/BG neuroimaging characteristics were associated with distinct etiologies. In particular, symmetric hemorrhagic abnormalities involving the thalamus were most frequently found within the respiratory virus group. CONCLUSIONS: T/BG involvement in patients with suspected encephalitis was associated with specific etiologies. In addition to agents with established predilection for the T/BG such as M. tuberculosis and arboviruses, a surprisingly high number of cases were associated with respiratory viruses, especially in children. Neuroimaging abnormalities in such patients can aid clinicians in narrowing the etiological scope and in guiding testing.


Assuntos
Gânglios da Base/patologia , Encefalite/etiologia , Encefalite/patologia , Neuroimagem , Núcleos Talâmicos/patologia , Vírus/isolamento & purificação , Adolescente , Adulto , Gânglios da Base/diagnóstico por imagem , Criança , Pré-Escolar , Encefalite/diagnóstico , Feminino , Humanos , Lactente , Masculino , Mycobacterium tuberculosis/isolamento & purificação , Príons/isolamento & purificação , Radiografia , Estudos Retrospectivos , Núcleos Talâmicos/diagnóstico por imagem , Adulto Jovem
15.
Osteoarthritis Cartilage ; 20(10): 1127-33, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22771774

RESUMO

OBJECTIVE: To validate a new method to analyze delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) measurements in the hip for early assessment of cartilage defects in femoroacetabular impingement (FAI). METHODS: We performed a retrospective review of 10 hips in 10 FAI patients, who underwent hip arthroscopy. T1-weighted images and dGEMRIC T(1) maps were acquired at 1.5 T on coronal planes, including the anterior-superior, superior, posterior-superior hip cartilage. For all slices, a region of interest (ROI) was defined over the central portion of the femoral cartilage, assumed to be healthy, and T1 values (x) were transformed to standard scores (z) using z = (x -µ)/σ, where µ and σ are the average and standard deviation of T1 in the femoral ROI. Diagnostic performance of the resulting standardized dGEMRIC maps was evaluated against intraoperative findings and compared with that of a previously proposed dGEMRIC analysis as well as morphologic assessment. RESULTS: Assuming z = -2 or z = -3 as the threshold between normal and degenerated cartilage, sensitivity, specificity and accuracy were 88%, 51% and 62%, and 71%, 63% and 65%, respectively. By using T1 = 500 ms as single threshold for all dGEMRIC T1 maps, these values became 47%, 58% and 55%, whereas they were 47%, 79% and 70% for morphologic evaluation. CONCLUSIONS: Standardized dGEMRIC can increase the sensitivity in detecting abnormal cartilage in FAI and has the potential to improve the clinical interpretation of dGEMRIC measurements in FAI, by removing the effect of inter- and intra-patient T1 variability.


Assuntos
Artroscopia/métodos , Cartilagem Articular/patologia , Meios de Contraste , Impacto Femoroacetabular/diagnóstico , Gadolínio , Articulação do Quadril/patologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
16.
Rofo ; 183(12): 1138-44, 2011 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-21959882

RESUMO

PURPOSE: The purpose of this study was to analyze potential quantitative and qualitative changes of the knee cartilage and joint indicative of early posttraumatic OA 4 years after ACL-reconstruction and to correlate the MRI-findings with the clinical outcome (CO). MATERIALS AND METHODS: 1.5 T MRI-scans were performed on 9 patients post-op and 4 years later. Using a high-resolution T 1-w-fs-FLASH-3D-sequence cartilage volume (cVol) and thickness (mTh) were quantified. Using standard PD-w fs and T 1-w sequences qualitative changes of the joint structures were analyzed based on the WORMS-score. CO was rated by an orthopaedic surgeon using Lysholm-score, OAK-score, Tegner-activity-score (TAS), and Arthrometer KT-1000 testing. RESULTS: Mean changes of cVol were -1.8 % (range: -5.9 %; + 0.7 %) and of mTh -0.8 % (range: -3.0 %; + 1.1 %). No significant change (95 %-CI) could be identified for any compartment. Three patients developed new peripatellar ostheophytes, acute trauma related changes mostly decreased. Mean outcome of Lysholm-score and OAK-score were 90 pts and 86 pts, mean TAS was 4.3 pts. Average maximum tibial translation reached 5.2 mm comparing to 6.7 mm on the healthy contralateral side. CONCLUSION: Despite a tendency towards decreased cVol and mTh 4 years after ACL-reconstruction qMRI revealed no significant cartilage loss. Newly developing osteophytes did not match with the observed good CO. This small pilot study motivates future quantitative and qualitative-structural MRI-based assessment of articular cartilage and other joint structures in order to improve diagnostic tools for the detection of early OA.


Assuntos
Reconstrução do Ligamento Cruzado Anterior , Cartilagem Articular/patologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/patologia , Projetos Piloto , Complicações Pós-Operatórias/patologia , Sensibilidade e Especificidade , Software
17.
Opt Express ; 19(3): 1691-8, 2011 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-21368982

RESUMO

We present a simplified acquisition and processing method for X-ray grating interferometry computed tomography (CT). The proposed approach eliminates the need to scan the gratings, thus allowing for a faster CT acquisition compared to methods presently in use. The contrast in the reconstructed images can be expressed as a linear combination of the absorption and refraction within the sample. Experimental images of a test phantom made of known materials and a human bone-cartilage sample prove the correctness of the method and show very good agreement with the theory. The here proposed approach might be highly interesting in many fields where a reduced imaging acquisition time is requested and/or where the radiation dose delivered to the sample has to be kept low, such as, for example, in in-vivo imaging.


Assuntos
Interferometria/instrumentação , Intensificação de Imagem Radiográfica/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Difração de Raios X/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Knee Surg Sports Traumatol Arthrosc ; 19(10): 1643-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21298254

RESUMO

PURPOSE: The posterior tibial slope has a huge influence on the kinematics of the knee. In several orthopedic interventions such as high tibial osteotomy and unicondylar or bicondylar knee replacement changing, the tibial slope can result in altered knee mechanics. Therefore, an exact preoperative measurement of the posterior tibial slope is mandatory. Several methods are used on conventional radiographs and CT scans, but until now there is no standard validated method. The aim of this study was to compare several methods and imaging techniques to measure the posterior tibial slope and to establish a standard and reliable measurement method by radiography. METHODS: Fourteen knees (seven cadavers) were scanned by a 64-slice CT, a 3T-MRI, and true lateral radiographs were performed. The anatomical references (TPAA = tibial proximal anatomical axis; ATC = anterior tibial cortex; PTC = posterior tibial cortex) and the new computed reference (MPA = mean of PTA and ATC) were compared by short as well as long radiographs, CT scan and MRI. The influence of a malrotation in radiographs of the knees was also analyzed. RESULTS: CT scan and MRI are suitable for the measurement of the medial and lateral posterior tibial slopes, the results of the radiographs varied depending on the method used. The new method (MPA) showed the best correlation to the CT scan (r = 0.997), even on short radiographs (10 cm distal the joint line). CONCLUSION: The measurement of the posterior tibial slope on a short lateral radiograph using the MPA is a reliable method and should be established as a standard. LEVEL OF EVIDENCE: Diagnostic study, Level II.


Assuntos
Articulação do Joelho/diagnóstico por imagem , Procedimentos Ortopédicos/métodos , Tíbia/anatomia & histologia , Tíbia/diagnóstico por imagem , Adulto , Fenômenos Biomecânicos , Pesos e Medidas Corporais/métodos , Pesos e Medidas Corporais/normas , Feminino , Humanos , Articulação do Joelho/anatomia & histologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Procedimentos Ortopédicos/normas , Padrões de Referência , Reprodutibilidade dos Testes , Rotação , Tomografia Computadorizada por Raios X
19.
Rofo ; 183(5): 432-40, 2011 May.
Artigo em Alemão | MEDLINE | ID: mdl-21113866

RESUMO

PURPOSE: To analyze locoregional deformation patterns indicative of contact areas in patellar cartilage after different loading exercises. MATERIALS AND METHODS: 7 healthy patellae were examined in-vivo before and immediately after standardized loading (kneeling, squatting or knee bends) and after 90 minutes of rest using a sagittal 3D-T1-w FLASH WE sequence (22 msec/ 9.8 msec/ 15°/ 0.3 × 0.3 × 1.5 mm³) at 3 T. After cartilage segmentation and 3D reconstruction, voxel-based and global precision errors (PR) were calculated. The former were used to determine significant differences in local cartilage thickness. Voxel-based 2σ-thickness difference maps were calculated to visualize locoregional deformation patterns. Global changes in volume (Vol), mean thickness (mTh) and cartilage-bone-interface area (CBIA) were calculated. RESULTS: The voxel-based PR depended on cartilage thickness (D) ranging from 0.12 - 0.35 mm. For D ≥ 1 mm the RF was < 0.31 mm (< voxel size), and for D ≥ 2 mm, the RF was < 0.22 mm. The global PR was 83 mm³ (2.4 %) for Vol, 0.06 mm (2.0 %) for mTh and 16 mm² (1.4 %) for CBIA. The focal cartilage deformation equaled 14 % of the local thickness reduction. The deformation areas were oval and located in the peripheral medial (more vertically oriented, all exercises) and caudo-lateral (more horizontally oriented, kneeling and knee bends) aspects of the patella and were least pronounced in knee bends. Significant changes for Vol/mTh ranged from 2.1 to 3.7 %. CONCLUSION: This MRI-based study is the first to identify in-vivo voxel-based patellar cartilage deformation patterns indicating contact and loading zones after kneeling and squatting. These zones are anatomically and functionally plausible and may represent areas where stress induced degeneration and subsequent OA can originate. The data may facilitate understanding of individual knee loading properties and help to improve and validate biomechanical models for the knee.


Assuntos
Cartilagem Articular/anatomia & histologia , Cartilagem Articular/fisiologia , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Patela/anatomia & histologia , Patela/fisiologia , Suporte de Carga/fisiologia , Adulto , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Masculino , Tamanho do Órgão/fisiologia , Valores de Referência , Processamento de Sinais Assistido por Computador , Adulto Jovem
20.
Br J Radiol ; 83(993): e182-4, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20739338

RESUMO

Primary arteritis of the central nervous system (CNS) comprises a heterogeneous group of CNS disorders, which is characterised by non-atheromatous inflammation and necrosis of the arterial wall. The clinical presentation is highly variable, with stroke being the most common manifestation. Conventional angiography is considered to be the best imaging tool for diagnosing the disease. However, angiographic findings, which usually show lumen irregularities and stenosis, are often unspecific and can occur with a variety of other vascular disorders, such as atherosclerosis and arterial dissection. Therefore, brain biopsies are often needed to confirm the diagnosis. Recent reports have shown that MRI is able to visualise contrast enhancement in subjects with known primary CNS arteritis.


Assuntos
Arterite/diagnóstico , Artérias Cerebrais , Angiografia por Ressonância Magnética/métodos , Meios de Contraste , Feminino , Humanos , Pessoa de Meia-Idade
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