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1.
Artigo em Inglês | MEDLINE | ID: mdl-38415864

RESUMO

PURPOSE: To identify gender differences in (1) the coronal alignment of functional knee phenotypes and (2) the JLCA (joint line convergence angle) in relation to the phenotype classification. METHODS: This study is a retrospective data analysis, including 12,099 osteoarthritic knee computed tomography (5025 male, 7074 female) analysed by Medacta software for hip-knee-ankle angle (HKA), femoral mechanical angle (FMA), tibial mechanical angle (TMA) and JLCA. The data were grouped into genders and combined according to the Functional Knee Phenotypes Classification. RESULTS: Out of 127 phenotypes for males and 131 for females, 17 common phenotypes were reported. The commonest four were similar for both genders with VARHKA177° NEUFMA93° NEUTMA87° (9.8% males, 9.50% females), followed by VARHKA174° NEUFMA93°VARTMA84° (7.1%) and VARHKA174°VARFMA90° NEUTMA87° (7.0%) for males and VARHKA174° NEUFMA93° NEUTMA87° (6.1%), VARHKA174° NEUFMA93°VARTMA84° (5.1%) for females. The commonest FMA and TMA (91.5° to 94.5° and 85.5° to 88.5°, respectively) were the same for both genders, however, the rest of the male population observed greater femoral varus than the female population (p < 0.001). JLCA values ranged from -28.4° to 8.2° in the overall study population. Males and females had a mean JLCA of -2.96° (±2.6° SD) and -2.66° (±2.8°7 SD), respectively, p < 0.001. CONCLUSIONS: Gender differences exist within the osteoarthritic knee phenotype. The male varus phenotype is influenced by FMA, while TMA values are similar across genders. JLCA variations show similarities to both TMA and FMA, suggesting JLCA is influenced by bone morphology more than by gender. These differences inform surgical decision-making for the personalised approach to the primary TKA. LEVEL OF EVIDENCE: Level III.

2.
Knee Surg Sports Traumatol Arthrosc ; 31(4): 1267-1275, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36326877

RESUMO

PURPOSE: The purpose of this study was to simulate and visualise the influence of the alignment strategy on bone resection in neutral knee phenotypes. It was hypothesised that different amounts of bone resection would be required depending on the alignment strategy chosen. The hypothesis was that by visualising the corresponding bone cuts, it would be possible to assess which of the different alignment strategies required the least change to the soft tissues for the chosen phenotype but still ensured acceptable component alignment and could, therefore, be considered the most ideal alignment strategy. METHODS: Simulations of the different alignment strategies (mechanical, anatomical, restricted kinematic and unrestricted kinematic) regarding their bone resections were performed on four common exemplary neutral knee phenotypes. NEUHKA0° VARFMA 90° VALTMA90°, NEUHKA0° NEUFMA 93° NEUTMA87°, NEUHKA0° VALFMA 96° NEUTMA87° and NEUHKA0° VALFMA 99° VARTMA84°. The phenotype system used categorises knees based on overall limb alignment (i.e. hip knee angle) but also considers joint line obliquity (i.e. TKA and FMA) and has been used globally since its introduction in 2019. These simulations are based on long leg weightbearing radiographs. It is assumed that a change of 1° in the alignment of the joint line corresponds to correspond to 1 mm of distal condyle offset. RESULTS: In the most common neutral phenotype NEUHKA0° NEUFMA 93° NEUTMA87°, with a prevalence of 30%, bone cuts remain below 4 mm regardless of alignment strategy. The greatest changes in the obliquity of the joint line can be expected for the mechanical alignment of the phenotype NEUHKA0° VALFMA 99° VARTMA84° where the medial tibia is raised by 6 mm and the lateral femur is shifted distally by 9 mm. In contrast, the NEUHKA0° VARFMA 90° VALTMA90° phenotype requires no change in joint line obliquity if the mechanical alignment strategy is used. CONCLUSION: Illustrations of alignment strategies help the treating surgeon to estimate the postoperative joint line obliquity. When considering the alignment strategy, it seems reasonable to prefer a strategy where the joint line obliquity is changed as little as possible. Although for the most common neutral knee phenotype the choice of alignment strategy seems to be of negligible importance, in general, even for neutral phenotypes, large differences in bone cuts can be observed depending on the choice of alignment strategy.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Extremidade Inferior/cirurgia , Tíbia/cirurgia , Fêmur/cirurgia , Fenótipo , Osteoartrite do Joelho/cirurgia , Estudos Retrospectivos
3.
Knee Surg Sports Traumatol Arthrosc ; 29(1): 90-99, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31563990

RESUMO

PURPOSE: Collagen meniscal implants (CMI) have variable imaging findings on MRI and it remains ambiguous, if alterations may be present in asymptomatic patients. The aim was, to evaluate MR morphological characteristics and volume of CMI in the early, mid- and long-term follow-up. METHODS: Fifty-seven patients (mean age, 43.6±11 years; 41 male/16 female) with good clinical outcome (subjective visual analogue scale for satisfaction < 2 and a Lysholm-score ≥ 84) after CMI were assessed retrospectively using MRI 1, 2 and 3-8 years postoperatively. CMI morphology, signal intensity (SI), homogeneity and size were assessed and a meniscal score was calculated. Chondral defects and bone marrow edema pattern were reported and summarized in a chondral score. Meniscal extrusion and volume were evaluated. Intra- and inter-reader reliabilities were calculated. Spearman and partial correlations were used (p < 0.05). RESULTS: One year postoperatively, the CMI varied in size [10% (4/40) normal, 30% (12/40) small, 60% (24/40) hypertrophic] and was hyperintense and inhomogeneous in all patients. At long-term follow-up, the size of CMI decreased [6% (1/17) resorbed, 18% (3/17) normal, 41% (7/17) small, 35% (6/17) hypertrophic]. The SI of the CMI changed to normal in only 13% (2/16). The majority was still hyperintense [87% (14/16)]. Less meniscal extrusion was present in the follow-up [71% (11/16) versus initially 93% (37/40)]. The meniscal score improved significantly (ρ = 0.28). Over time, full-thickness femoral chondral defects were increasingly present [65% (10/17) versus initially 33% (13/40)] and the chondral score worsened significantly (p = 0.017). CONCLUSION: Abnormal and inhomogeneous SI and irregular margins of the early postoperative CMI on MRI are findings seen in patients with good clinical results and should not necessarily be overcalled when reporting MRI. These features tend to decrease over time. LEVEL OF EVIDENCE: IV.


Assuntos
Colágeno/uso terapêutico , Meniscos Tibiais/cirurgia , Implantação de Prótese/métodos , Adulto , Doenças da Medula Óssea/epidemiologia , Cartilagem Articular/patologia , Edema/epidemiologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Meniscos Tibiais/diagnóstico por imagem , Menisco/cirurgia , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Resultado do Tratamento
4.
J Clin Med ; 9(7)2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645935

RESUMO

Nocardiosis is primarily an opportunistic infection affecting immunosuppressed individuals, in whom it most commonly presents as pulmonary infection and sometimes cerebral abscesses. Isolated abdominal or retroperitoneal nocardiosis is rare. Here, we report the second case, to our knowledge, of isolated abdominal nocardiosis due to Nocardia paucivorans and provide a comprehensive review of intra-abdominal nocardiosis. The acquisition of abdominal nocardiosis is believed to occur via hematogenous spreading after pulmonary or percutaneous inoculation or possibly via direct abdominal inoculation. Cases of Nocardia peritonitis have been reported in patients on peritoneal dialysis. Accurate diagnosis of abdominal nocardiosis requires histological and/or microbiological examination of appropriate, radiologically or surgically obtained biopsy specimens. Malignancy may initially be suspected when the patient presents with an abdominal mass. Successful therapy usually includes either percutaneous or surgical abscess drainage plus prolonged combination antimicrobial therapy.

5.
Knee Surg Sports Traumatol Arthrosc ; 28(4): 1029-1035, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31263926

RESUMO

PURPOSE: The primary purpose of this retrospective study with prospectively collected data was to evaluate the clinical value of SPECT/CT, in particular its impact on clinical diagnosis and patient management, in patients with pain, stiffness, or swelling after primary total knee arthroplasty (TKA). The secondary purpose was to determine the sensitivity and the specificity of SPECT/CT for different pathologies such as loosening and patellofemoral overloading. METHODS: A retrospective analysis was carried out on 214 knees in 202 consecutive patients (mean age 69 ± 11 years) with persistent or recurrent knee pain after TKA. All patients underwent clinical examination, standardised radiographs, and 99mTc-hydroxymethane diphosphonate (HDP) SPECT/CT as part of a routine diagnostic algorithm. The diagnoses before and after SPECT/CT and final treatment were recorded. TKA component position was routinely measured on 3D-reconstructed images. Intensity and anatomical distribution of bone tracer uptake were determined. RESULTS: SPECT/CT changed the clinical diagnosis and final treatment in 139/214 (65%) knees. In 117 (54.7%) out of 214 patients, revision surgery was proposed following SPECT/CT. Early onset of pain was significantly (p = 0.011) correlated with tibiofemoral stress pattern in SPECT/CT. A total of 86 knees (40.2%) were surgically revised using semi-constrained or fully constrained TKA. In 35 patients, a secondary patellar resurfacing was performed. SPECT/CT showed the clinical diagnosis to be incorrect for suspicion of tibial component loosening in 56 patients (26.2%), femoral component loosening in 53 patients (24.8%), and patellofemoral overloading/progressive patellofemoral osteoarthritis in 26 patients (12.1%) and provided different underlying causes of persistent knee pain after TKA. Likewise, SPECT/CT identified tibial component loosening in 8 patients (3.7%), femoral component loosening in 4 patients (1.9%), and patellofemoral OA in 71 patients (33.2%) without prior clinical suspected diagnosis. The sensitivity and specificity of SPECT/CT for detection of patellofemoral OA was 96.5% and 96.2%, respectively. The sensitivity and specificity for detection of tibial component loosening was 96.0% and 100%, respectively. The sensitivity and specificity for detection of femoral component loosening was 95.0% and 100%, respectively. CONCLUSION: The diagnostic benefits of SPECT/CT in the challenging and complex cohort of patients with pain after primary TKA have been proven. The excellent sensitivity and specificity for detection of tibial or femoral component loosening and diagnosis of patellofemoral OA have been surgically confirmed. Due to the benefits in establishing the correct diagnosis, SPECT/CT should be implemented as part of the routine diagnostic algorithm for patients with pain after primary TKA. LEVEL OF EVIDENCE: II.


Assuntos
Artroplastia do Joelho/efeitos adversos , Osso e Ossos/diagnóstico por imagem , Osteoartrite do Joelho/diagnóstico por imagem , Falha de Prótese , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento Tridimensional , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Dor/cirurgia , Patela/cirurgia , Radiografia , Estudos Retrospectivos , Sensibilidade e Especificidade , Tíbia/cirurgia
6.
Br J Radiol ; 92(1099): 20180937, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31045438

RESUMO

OBJECTIVE: We aim to compare factors influencing safety, success rate and radiation dose of CT-guided biopsies and drainages in a non-teaching setting with experienced operators vs a teaching setting with residents. METHODS: A total of 1021 cases were retrospectively analyzed regarding lesion size, distance from skin, procedure duration, radiation dose, complications and clinical success. Procedures were grouped into biopsies of lung, liver, (remaining) abdomen, musculoskeletal system (MSK) and drainages of any region. Procedures in non-teaching setting were performed by experienced operators (full time interventional radiology staff), teaching setting consisted of residents under supervision of interventional radiology staff. RESULTS: Overall clinical success rate was 93.6 % [experienced (exp.) vs teaching setting: 93.5 and 93.6 %, p = 0.97]. Overall complication rate was 7.2% (5.7% minor, 1.6% major; exp. vs teaching: 8.0 and 6.5 %, p = 0.67]. Experienced operators performed chest and liver biopsies faster even though they were facing smaller lesions. Multiple regression analysis revealed that depth from skin significantly increased procedure duration by 36.8 s per cm (p < 0.001) and also radiation dose by 5.4 mGy per cm (p < 0.001) in all interventions. On average, teaching setting increased the duration of an intervention by 209.8 s and total radiation dose by 10.6 mGy (p < 0.001, p < 0.001 respectively). CONCLUSION: CT guided interventions can be performed safe und successful disregarding anatomical parameters or teaching setting. Depth from skin and teaching setting should be taken into account both from a clinical and a time-conscious point of view since they increase radiation dose and prolong operations. ADVANCES IN KNOWLEDGE: This is the first study with >1000 interventions which shows and quantifies the impact of lesion depth and teaching setting in CT-guided interventions.


Assuntos
Competência Clínica/estatística & dados numéricos , Doses de Radiação , Exposição à Radiação/estatística & dados numéricos , Radiografia Intervencionista/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Feminino , Humanos , Internato e Residência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tempo
7.
Knee Surg Sports Traumatol Arthrosc ; 26(6): 1602-1609, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29026941

RESUMO

PURPOSE: The optimal coronal alignment is still under debate. However, in most of the studies, alignment was only assessed using radiographs, which are not accurate enough for assessment of tibial and femoral TKA position. The primary purpose of this study was to assess the relationship between coronal TKA alignment using 3D-reconstructed CTs and clinical outcome in patients with preoperative varus in comparison with patients with natural or valgus deformity. It was the hypothesis that neutral limb alignment shows a better outcome after TKA. METHODS: Prospectively collected data of 38 patients were included. The clinical and radiological follow-up was 24 months. The patients were grouped into two groups with regard to their preoperative limb alignment. Group A (varus) consisted of 21 patients with preoperative varus of 3° or more, while group B (non-varus) consisted of 17 patients with neutral (- 3 < 0 > + 3) or valgus alignment (> + 3). For assessment of TKA component position and orientation, 3D-reconstructed CT was used. The measurements of the deviation from the whole limb mechanical axis (HKA angle) and the joint line alignment in the femoral (mLDFA) and the tibial side (MPTA) were assessed in the preoperative leg as well as during follow-up after TKA. For clinical outcome assessment, the Knee Society Score (KSS) was used at 1 and 2 years postoperatively. Correlation between KSS score and each variable was done using a linear and quadratic regression model (p < 0.05). RESULTS: The mean postoperative HKA angle was - 1.3 (varus) in the varus group and + 1.4 (valgus) in the non-varus group. Overall, significant correlations between the preoperative and postoperative alignments were found. In the preoperatively non-varus group, a highly significant correlation was found between neutral limb alignment (HKA = 0° ± 3°) and higher KSS (r 2 = 0.74, p = 0.00). In the varus group, no correlation was found between the postoperative whole limb alignment and the components' position in the coronal plane to KSS score. CONCLUSION: A significant correlation was found between neutral limb alignment and higher KSS only in patients with preoperative non-varus alignment. The concept of constitutional varus alignment is still under debate. Moreover, it appears that one should aim for a more individualized, alignment target based on the individual knee morphotype. LEVEL OF EVIDENCE: Diagnostic study, Level II.


Assuntos
Artroplastia do Joelho/métodos , Mau Alinhamento Ósseo/diagnóstico por imagem , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/cirurgia , Idoso , Idoso de 80 Anos ou mais , Mau Alinhamento Ósseo/prevenção & controle , Mau Alinhamento Ósseo/cirurgia , Feminino , Fêmur/cirurgia , Humanos , Imageamento Tridimensional , Joelho/cirurgia , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tíbia/cirurgia , Tomografia Computadorizada por Raios X
8.
J Magn Reson Imaging ; 40(6): 1408-13, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24338875

RESUMO

PURPOSE: To investigate the origin of skeletal muscle BOLD MRI alterations in patients with systemic sclerosis (SSc) by correlating BOLD MRI T2* signal of calf muscles with microcirculatory blood flow of calf skin measured by laser Doppler flowmetry (LDF). MATERIALS AND METHODS: BOLD MRI (3T) and LDF measurements were performed in 12 consecutive SSc patients (6 women, 6 men; mean age 54.0 ± 10.0 years) and 12 healthy volunteers (4 men, 8 women; mean age 44.7 ± 13.1 years). For both modalities, the same cuff compression paradigm at mid-thigh level was used. LDF datasets were acquired using a PeriScan PIM II Imager (Perimed AB, Stockholm, Sweden) at the upper calf corresponding to the level of MR imaging. Cross-correlations of BOLD and LDF signal intensity changes depending on time lags between both time series were calculated. RESULTS: Maximal cross-correlations of BOLD T2* and LDF measurements were calculated as 0.93 (healthy volunteers) and 0.94 (SSc patients) for a BOLD time lag of approximately 10 s. Key parameter analysis suggested that in contrast to hyperemic BOLD signal loss at maximum value in SSc patients, ischemic T2* decrease cannot be explained by differences of tissue perfusion. CONCLUSION: Skeletal muscle BOLD T2* signal in SSc patients is closely correlated with changes of microperfusion as detected by LDF.


Assuntos
Fluxometria por Laser-Doppler/métodos , Angiografia por Ressonância Magnética/métodos , Músculo Esquelético/irrigação sanguínea , Oxigênio/sangue , Escleroderma Sistêmico/fisiopatologia , Pele/irrigação sanguínea , Adulto , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Masculino , Músculo Esquelético/diagnóstico por imagem , Oximetria/métodos , Reprodutibilidade dos Testes , Escleroderma Sistêmico/diagnóstico , Sensibilidade e Especificidade , Pele/diagnóstico por imagem , Estatística como Assunto , Ultrassonografia
9.
J Magn Reson Imaging ; 38(4): 845-51, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23441019

RESUMO

PURPOSE: To prospectively compare calf muscle BOLD MRI with transcutaneous oxygen pressure (TcPO2 ) measurement in patients with systemic sclerosis (SSc) and healthy volunteers and thereby get insight into the pathogenesis of vasculopathy in this connective tissue disorder. MATERIALS AND METHODS: Twelve patients with SSc (6 women and 6 men, mean age 53.5 ± 10.0 years) and 12 healthy volunteers (4 men and 8 women, mean age 47 ± 12.1 years) were examined using muscle BOLD MRI and TcPO2. A cuff compression at mid-thigh level was performed to provoke ischemia and reactive hyperemia. BOLD measurements were acquired on a 3 Tesla whole body-scanner in the upper calf region using a multi-echo EPI-sequence with four echo-times (TE: 9/20/31/42 ms) and a repetition time of 2 s. Empirical cross-correlation analysis depending on time lags between BOLD- and TcPO2-measurements was performed. RESULTS: Maximal cross-correlation of BOLD T2*- and TcPO2-measurements was calculated as 0.93 (healthy volunteers) and 0.90 (SSc patients) for a time lag of approximately 40 s. Both modalities showed substantial differences regarding time course parameters between the SSc patients and healthy volunteers. CONCLUSION: Skeletal muscle BOLD MRI correlated very well with TcPO2 . T2* changes seem to reflect reoxygenation deficits in deeper muscle tissue of SSc patients.


Assuntos
Isquemia/patologia , Imageamento por Ressonância Magnética , Microcirculação , Oxigênio/metabolismo , Escleroderma Sistêmico/metabolismo , Escleroderma Sistêmico/patologia , Adulto , Estudos de Casos e Controles , Interpretação Estatística de Dados , Feminino , Humanos , Perna (Membro)/patologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Pressão , Estudos Prospectivos , Projetos de Pesquisa
11.
Int Orthop ; 36(12): 2485-90, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23129224

RESUMO

PURPOSE: The purpose of this study was to identify predictive factors for the occurrence of complications in a consecutive series of patients who underwent step-cut tibial tubercle osteotomy (TTO) and subsequent screw refixation in primary total knee arthroplasty (TKA). METHODS: Using standardised conventional radiographs, critical parameters including TTO length and depth, proximal abutment width (OT), and orientation and placement of fixation screws were measured in 422 patients (mean age of 71 years and a follow-up time range of one to five years) with two screw fixations. RESULTS: Medial spatial orientation in the distal screw (11 %, p=0.046), the TTO length (<55.4 mm, p=0.013), the OT width (<14 mm, p=0.002) and the distance of the distal refixation screw from the TKA (<51.7 mm, p=0.003) were significant factors for the occurrence of complications. CONCLUSIONS: Age, gender, comorbidities, height, weight and/or the body mass index had no significant influence on the occurrence of complications. The TTO-related complication rate was 3 %. Consideration of these key surgical factors leads to improved outcomes.


Assuntos
Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/métodos , Osteotomia/efeitos adversos , Osteotomia/métodos , Tíbia/cirurgia , Idoso , Idoso de 80 Anos ou mais , Parafusos Ósseos , Feminino , Seguimentos , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Radiografia , Estudos Retrospectivos , Falha de Tratamento , Resultado do Tratamento
12.
Arthritis Res Ther ; 14(5): R209, 2012 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-23036642

RESUMO

INTRODUCTION: Muscle symptoms in systemic sclerosis (SSc) may originate from altered skeletal muscle microcirculation, which can be investigated by means of blood oxygenation level dependent (BOLD) magnetic resonance imaging (MRI). METHODS: After ethics committee approval and written consent, 11 consecutive SSc patients (5 men, mean age 52.6 years, mean SSc disease duration 5.4 years) and 12 healthy volunteers (4 men, mean age 45.1 years) were included. Subjects with peripheral arterial occlusive disease were excluded. BOLD MRI was performed on calf muscles during cuff-induced ischemia and reactive hyperemia, using a 3-T whole-body scanner (Verio, Siemens, Erlangen, Germany) and fat-suppressed single-short multi-echo echo planar imaging (EPI) with four different effective echo times. Muscle BOLD signal time courses were obtained for gastrocnemius and soleus muscles: minimal hemoglobin oxygen saturation (T2*min) and maximal T2* values (T2*max), time to T2* peak (TTP), and slopes of oxygen normalization after T2* peaking. RESULTS: The vast majority of SSc patients lacked skeletal muscle atrophy, weakness or serum creatine kinase elevation. Nevertheless, more intense oxygen desaturation during ischemia was observed in calf muscles of SSc patients (mean T2*min -15.0%), compared with controls (-9.1%, P = 0.02). SSc patients also had impaired oxygenation during hyperemia (median T2*max 9.2% vs. 20.1%, respectively, P = 0.007). The slope of muscle oxygen normalization was significantly less steep and prolonged (TTP) in SSc patients (P<0.001 for both). Similar differences were found at a separate analysis of gastrocnemius and soleus muscles, with most pronounced impairment in the gastrocnemius. CONCLUSIONS: BOLD MRI demonstrates a significant impairment of skeletal muscle microcirculation in SSc.


Assuntos
Microcirculação/fisiologia , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/patologia , Escleroderma Sistêmico/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Hiperemia/patologia , Hiperemia/fisiopatologia , Isquemia/patologia , Isquemia/fisiopatologia , Perna (Membro)/irrigação sanguínea , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Escleroderma Sistêmico/patologia
13.
J Magn Reson Imaging ; 35(6): 1253-65, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22588992

RESUMO

Blood oxygenation-level dependent (BOLD) MRI has gained particular attention in functional brain imaging studies, where it can be used to localize areas of brain activation with high temporal resolution. To a higher degree than in the brain, skeletal muscles show extensive but transient alterations of blood flow between resting and activation state. Thus, there has been interest in the application of the BOLD effect in studying the physiology of skeletal muscles (healthy and diseased) and its possible application to clinical practice. This review outlines the potential of skeletal muscle BOLD MRI as a diagnostic tool for the evaluation of physiological and pathological alterations in the peripheral limb perfusion, such as in peripheral arterial occlusive disease. Moreover, current knowledge is summarized regarding the complex mechanisms eliciting BOLD effect in skeletal muscle. We describe technical fundaments of the procedure that should be taken into account when performing skeletal muscle BOLD MRI, including the most often applied paradigms to provoke BOLD signal changes and key parameters of the resulting time courses. Possible confounding effects in muscle BOLD imaging studies, like age, muscle fiber type, training state, and drug effects are also reviewed in detail.


Assuntos
Imageamento por Ressonância Magnética/métodos , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Doenças Musculares/patologia , Doenças Musculares/fisiopatologia , Oxigênio/metabolismo , Velocidade do Fluxo Sanguíneo , Humanos
14.
MAGMA ; 25(4): 251-61, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22374263

RESUMO

Blood-oxygenation-level-dependent (BOLD) contrast in magnetic resonance (MR) imaging of skeletal muscle mainly depends on changes of oxygen saturation in the microcirculation. In recent years, an increasing number of studies have evaluated the clinical relevance of skeletal muscle BOLD MR imaging in vascular diseases, such as peripheral arterial occlusive disease, diabetes mellitus, and chronic compartment syndrome. BOLD imaging combines the advantages of MR imaging, i.e., high spatial resolution, no exposure to ionizing radiation, with functional information of local microvascular perfusion. Due to intrinsic contrast provoked via changes in hemoglobin oxygen saturation, it is a safe and easy applicable procedure on standard whole-body MR devices. Therefore, BOLD MR imaging of skeletal muscle is a potential new diagnostic tool in the clinical evaluation of vascular, inflammatory, and muscular pathologies. Our review focuses on the current evidence concerning the use of BOLD MR imaging of skeletal muscle under pathological conditions and highlights ways for future clinical and scientific applications.


Assuntos
Imageamento por Ressonância Magnética/métodos , Músculo Esquelético/irrigação sanguínea , Oxigênio/sangue , Síndromes Compartimentais/diagnóstico , Angiopatias Diabéticas/diagnóstico , Humanos , Interpretação de Imagem Assistida por Computador , Microcirculação/fisiologia , Doença Arterial Periférica/diagnóstico
15.
Surg Radiol Anat ; 33(9): 775-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21590340

RESUMO

PURPOSE: Pathologic changes of the glenohumeral joint, like a long-standing overloading or an accident often lead to severe glenohumeral osteoarthritis, and a glenohumeral joint replacement could be necessary. Joint instability and glenoid loosening are the most common post-operative complications, which can be caused by eccentric loading of the glenoid, if the humeral head is malcentered. If these malcentered cases could be identified pre-operatively, the pathologic position of the humeral head could be fixed intra-operatively and complication may be prevented. Computed tomography osteoabsorptiometry (CT-OAM) is a useful method to determine the distribution of mineralisation in the subchondral bone as a marker for the long-term loading history of a joint. The objective of this study was to gain information about the mineralisation distribution in the subchondral bone plate of the humeral head. METHODS: By the use of CT-OAM, the distribution of the subchondral mineralisation of 69 humeral heads was investigated and groups of mineralisation patterns were built. To evaluate if differences in age exist, the mean values of the two groups were compared using t test. RESULTS: 49 humeral heads (71% of 69 specimens) showed bicentric subchondral mineralisation patterns with ventral and dorsal maxima, 20 humeral heads (29% of 69 specimens) could be classified as monocentric with a centro-dorsal maximum. We found no statistical significant difference between the age of the monocentric and the bicentric group on a significance level of 95%. CONCLUSION: We could show that stress distribution at the humeral head is typically bicentric with a ventral and dorsal maximum. However, other mineralisation patterns may occur under pathologic circumstances. The pre-operative identification of such cases by the use of CT-OAM could help to improve the post-operative results in shoulder surgery.


Assuntos
Densidade Óssea , Cabeça do Úmero/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Cabeça do Úmero/diagnóstico por imagem , Cabeça do Úmero/fisiologia , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Adulto Jovem
16.
J Am Coll Surg ; 211(1): 81-91, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20610253

RESUMO

BACKGROUND: Knowledge of the factors associated with longer-term reduced capacity to work (RCW) is lacking in patients after polytrauma. STUDY DESIGN: We studied a prospectively collected cohort of polytrauma survivors (n = 115; age 39.5 +/- 20.6 years [mean +/- SD]; 98% blunt trauma; Injury Severity Score [ISS] 27.5 +/- 8.2) at a university trauma center. Uni- and multivariable analyses of patient, trauma, and treatment characteristics as well as parameters of self-reported functional outcomes were studied to determine their association with a reduced capacity to work (RCW) at least 2 years after injury. RESULTS: Postinjury quality of life was worse compared with preinjury status in univariate analysis (eg, Euro Quality of Life Group Visual Analogue Scale [EQ VAS] 66.2 +/- 24.4 vs 89.7 +/- 14.7; p = <0.001). In 53% of patients (n = 61), an RCW was found and functional outcomes were significantly lower than those in non-RCW patients (p < 0.001). Lower educational status (odds ratio [OR] 0.25; 95% CI 0.07 to 0.92; p = 0.036), higher ISS (OR 1.12; 95% CI 1.02 to 1.22; p = 0.017), less time in the emergency room (OR 0.92; 95% CI 0.86 to 0.97; p = 0.005), higher mean nurse labor per day and patient (OR 1.01; 95% CI 1.000 to 1.004; p = 0.033), and a reduced Nottingham Health Profile value (OR 1.10; 95% CI 1.06 to 1.15; p < 0.001) were associated with an RCW in the multiple logistic regression model (proportion of variance explained: 0.74). CONCLUSIONS: In this cohort of patients surviving polytrauma, approximately 50% of patients sustained longer-term RCW. Several characteristics, such as level of education or trauma severity, showed an independent association with patients' capacity to work, which was significantly associated with patients' self-rated scorings of well-being.


Assuntos
Traumatismo Múltiplo , Qualidade de Vida , Trabalho , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Distribuição de Qui-Quadrado , Avaliação da Deficiência , Escolaridade , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recuperação de Função Fisiológica , Inquéritos e Questionários , Suíça , Fatores de Tempo , Centros de Traumatologia , Índices de Gravidade do Trauma
17.
Mol Ther ; 18(3): 651-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19935776

RESUMO

Recombinant vaccinia virus (rVV) encoding tumor-associated antigens (TAAs) and adhesion or costimulatory molecules may represent important immunogenic reagents for cancer immunotherapy. Recently, intranodal (IN) antigen administration was suggested to be more immunogenic than intradermal (ID) vaccination. However, IN rVV administration has not been attempted so far. We used a rVV encoding gp100(280-288), Melan-A/MART-1(27-35) and tyrosinase(1-9) HLA-A0201 restricted epitopes and CD80 and CD86 costimulatory molecules in stage III and IV melanoma patients in a phase 1/2 trial. Of 15 patients initiating treatment, including two cycles of IN immunization, each comprising one rVV administration and three recall injections of the corresponding peptides, accompanied by subcutaneous granulocyte macrophage-colony stimulating factor supplementation, five withdrew due to progressing disease. Of 10 remaining patients seven showed evidence of induction of cytotoxic T lymphocytes (CTLs) directed against at least one epitope under investigation, as detectable by limiting dilution analysis (LDA) of specific precursors and multimer staining. Adverse reactions were mild (National Cancer Institute (NCI) grade 1-2) and mainly represented by fever, skin rashes, and pruritus. These data indicate that IN administration of rVV encoding melanoma-associated epitopes and costimulatory molecules is safe and immunogenic.


Assuntos
Antígenos de Neoplasias/metabolismo , Imunização/métodos , Melanoma/patologia , Melanoma/terapia , Vaccinia virus/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Vacinas Anticâncer/uso terapêutico , Progressão da Doença , Epitopos/química , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Linfócitos T Citotóxicos/metabolismo
18.
Artigo em Inglês | MEDLINE | ID: mdl-19431070

RESUMO

The purpose of this study was to demonstrate first magnetic resonance (MR)-guided stenting of iliac and supraaortic arteries using a polyetheretherketone-based (PEEK) MR-compatible guide wire. In vitro and animal experiments were performed in a short magnet wide-bore scanner (1.5 Tesla, Espree, Siemens Healthcare, Erlangen, Germany). For all experiments, a 0.035'' MR-compatible guide wire prototoype was used. This wire had a compound core of PEEK with reinforcing fibres, a soft and atraumatic tip and a hydrophilic coating. For its passive visualization, paramagnetic markings were attached. All experiments were performed through a vascular introducer sheath under MR-guidance. In vitro repetitive selective over the wire catheterizations of either the right carotid artery and the left subclavian artery were performed. In vivo, selective catheterization and over-the-wire stenting of the brachiocephalic trunk and the left subclavian artery were performed. The common iliac arteries were catheterized retrogradely (left) and cross-over (right). Angioplasty and stenting were performed over-the-wire. All procedures were successful. Visibility of the PEEK-based guide-wire was rated good in vitro and acceptable in vivo. Guide wire pushability and endovascular device support were good. The PEEK-based MR-compatible guide wire is well visible and usable under MR-guidance. It supports over-the-wire treatment of iliac arteries and supraaortic arteries.


Assuntos
Cetonas , Imagem por Ressonância Magnética Intervencionista/métodos , Polietilenoglicóis , Stents , Angioplastia/métodos , Animais , Aorta/cirurgia , Benzofenonas , Materiais Biocompatíveis , Tronco Braquiocefálico/cirurgia , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/métodos , Desenho de Equipamento , Feminino , Artéria Ilíaca/cirurgia , Polímeros , Artéria Subclávia/cirurgia , Suínos
19.
Invest Radiol ; 44(4): 234-41, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19252440

RESUMO

OBJECTIVES: Demonstrate the usability of a new polyetheretherketone (PEEK)-based MR-compatible guidewire for renal artery catheterization, angioplasty, and stenting under MR-guidance using MR-visible markers, in vitro and in vivo. MATERIAL AND METHODS: The new 0.035'' guidewire with fiber-reinforced PEEK core, a soft tip, and a hydrophilic coating was used. Paramagnetic markings were coated on the wire and nonbraided catheters for passive visualization. Bending stiffness of the guidewire was compared with available hydrophilic guidewires (Terumo Glidewire Stiff and Standard). A human aortic silicon phantom and 2 pigs were used. The study was animal care and use approved by the committee. Under MR-guidance, renal arteries were catheterized, balloon angioplasty was performed, and balloon expandable renal artery stents were deployed in vivo. Post mortem autopsy was performed. Guidewire visibility, pushability, steerability, and device-support capabilities of the marked guidewire were qualitatively assessed. Procedure times were recorded. RESULTS: Bending stiffness of the new PEEK-based wire was comparable with Standard Glidewire. In vitro and in vivo guidewire guidance, catheter configuration, renal artery catheterization, and balloon angioplasty were successful. In pigs, stent deployments were successful in both renal arteries. Autopsy revealed acceptable stent positioning. Guidewire visibility through applied markers was acceptable. Steerability, pushability, and device support were good in vitro and in vivo. CONCLUSIONS: The PEEK-based guide allows percutaneous MR-guided renal artery angioplasty and stenting with sufficient visibility, good steerability, pushability, and device support.


Assuntos
Angioplastia/métodos , Cetonas , Imagem por Ressonância Magnética Intervencionista/métodos , Imagens de Fantasmas , Polietilenoglicóis , Obstrução da Artéria Renal/cirurgia , Stents , Animais , Benzofenonas , Humanos , Polímeros , Suínos
20.
Eur Radiol ; 19(2): 509-15, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18795296

RESUMO

The purpose was to evaluate the effect of percutaneous transluminal angioplasty (PTA) of the superficial femoral artery (SFA) on the blood oxygenation level-dependent (BOLD) signal change in the calf musculature of patients with intermittent claudication. Ten patients (mean age, 63.4+/-11.6 years) with symptomatic peripheral arterial occlusive disease (PAOD) caused by SFA stenoses were investigated before and after PTA. Patients underwent BOLD-MRI 1 day before and 6 weeks after PTA. A T2*-weighted single-shot multi-echo echo-planar MR-imaging technique was applied. The BOLD measurements were acquired at mid-calf level during reactive hyperaemia at 1.5 T. This transient hyperperfusion of the muscle tissue was provoked by suprasystolic cuff compression. Key parameters describing the BOLD signal curve included maximum T2* (T2*(max)), time-to-peak to reach T2*(max) (TTP) and T2* end value (EV) after 600 s of hyperemia. Paired t-tests were applied for statistic comparison. Between baseline and post-PTA, T2*(max) increased from 11.1+/-3.6% to 12.3+/-3.8% (p=0.51), TTP decreased from 48.5+/-20.8 s to 35.3+/-11.6 s (p=0.11) and EV decreased from 6.1+/-6.4% to 5.0+/-4.2% (p=0.69). In conclusion, BOLD-MRI reveals changes of the key parameters T2*(max), TTP, and EV after successful PTA of the calf muscles during reactive hyperaemia.


Assuntos
Angioplastia com Balão/métodos , Aterosclerose/patologia , Imageamento por Ressonância Magnética/métodos , Músculos/patologia , Doenças Vasculares Periféricas/diagnóstico , Doenças Vasculares Periféricas/patologia , Idoso , Angiografia Digital/métodos , Aterosclerose/diagnóstico , Feminino , Humanos , Perna (Membro)/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Perfusão , Fatores de Risco , Fatores de Tempo
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