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1.
Int J Infect Dis ; 81: 140-148, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30658169

RESUMO

BACKGROUND: Pulmonary nocardiosis (PN) is an uncommon but potentially life-threatening infection. Most of our knowledge on PN is derived from case reports and small case series. Increasing incidence rates of PN have been reported recently. The aim of this study was to describe the clinical course of and risk factors for PN in four Western European countries and to estimate population-based annual hospitalization rates. METHODS: This was a retrospective evaluation (1995-2011) of the clinical course of and risk factors for PN in patients at 11 hospitals in four European countries (Germany, Austria, Switzerland, and the Netherlands). Population-based estimates of hospitalization rates for PN in Germany (2005 to 2011) were calculated using official German nationwide diagnosis-related groups (DRG) hospital statistics. RESULTS: Forty-three patients fulfilled stringent criteria for proven (n=8) and probable (n=35) PN; seven had extrapulmonary dissemination. For these 43 patients, the major risk factors for PN were immunocompromising (83.7%) and/or pulmonary (58.1%; as only comorbidity in 27.9%) comorbidities. The median duration of PN targeted therapy was 12 weeks. Distinctive patterns of resistance were observed (imipenem susceptibility: Nocardia farcinica 33.3%; Nocardia asteroides 66.7%). The overall mortality rate was 18.9% (50% in disseminated PN). Over time, annual PN hospitalization rates remained unchanged at around 0.04/100000, with the highest rate among men aged 75-84 years (0.24/100000). CONCLUSIONS: PN is a rare, but potentially life-threatening disease, and mainly affects immunocompromised elderly males. Overall, annual hospitalization rates remained stable between 2005 and 2011.


Assuntos
Hospitalização/estatística & dados numéricos , Nocardiose/epidemiologia , Adulto , Idoso , Comorbidade , Feminino , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Nocardiose/tratamento farmacológico , Nocardiose/etiologia , Estudos Retrospectivos , Fatores de Risco
2.
Rofo ; 187(5): 380-4, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25962673

RESUMO

PURPOSE: Various technologies have been established for DICOM data exchange in radiology. In addition to the patient CD, online transfers via VPN (virtual private network) or DICOM email are common practice. However, dedicated network solutions are generally not appropriate for data exchange with occasional and spontaneous partners due to missing infrastructure at the partner institutions and/or complex setup procedures. The purpose was to develop a practical solution to complement the established technologies to allow users worldwide to transfer images without registration. MATERIALS AND METHODS: The development of the xPIPE system is based on Java and various software libraries. A client hosted on a website enables sending DICOM data to a receiving system of the hospital. RESULTS: The new xPIPE system creates a gateway to a receiving hospital which is accessible from any point worldwide, giving other hospitals, clinics and patients a simple and secure method to transmit DICOM data without intermediate storage on external servers. CONCLUSION: The system was deployed at the University Hospital Münster and subsequently widely used even without information events and training. Data protection during transfer is ensured by the use of signatures and encryption. From the user's perspective the system has only minor technical requirements and can be used with minimal setup effort.


Assuntos
Segurança Computacional , Confidencialidade , Armazenamento e Recuperação da Informação/métodos , Internet , Registro Médico Coordenado/métodos , Sistemas de Informação em Radiologia/organização & administração , Software , Algoritmos , Registros Eletrônicos de Saúde/organização & administração , Linguagens de Programação , Design de Software , Interface Usuário-Computador
3.
Clin Exp Immunol ; 173(1): 112-20, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23607747

RESUMO

Growing evidence suggests a prominent role of the complement system in the pathogenesis of cardio- and cerebrovascular diseases (CVD). Mannan-binding lectin-associated serine proteases (MASPs) MASP-1 and MASP-2 of the complement lectin pathway contribute to clot formation and may represent an important link between inflammation and thrombosis. MBL-associated protein MAp44 has shown cardioprotective effects in murine models. However, MAp44 has never been measured in patients with CVD and data on MASP levels in CVD are scarce. Our aim was to investigate for the first time plasma levels of MAp44 and MASP-1, -2, -3 concomitantly in patients with CVD. We performed a pilot study in 50 healthy volunteers, in stable coronary artery disease (CAD) patients with one-vessel (n = 51) or three-vessel disease (n = 53) and age-matched controls with normal coronary arteries (n = 53), 49 patients after myocardial infarction (MI) and 66 patients with acute ischaemic stroke. We measured MAp44 and MASP-1 levels by in-house time-resolved immunofluorometric assays. MASP-2 and MASP-3 levels were measured using commercial enzyme-linked immunosorbent assay kits. MASP-1 levels were highest in subacute MI patients and lowest in acute stroke patients. MASP-2 levels were lower in MI and stroke patients compared with controls and CAD patients. MASP-3 and MAp44 levels did not differ between groups. MASP or MAp44 levels were not associated with severity of disease. MASP and MAp44 levels were associated with cardiovascular risk factors including dyslipidaemia, obesity and hypertension. Our results suggest that MASP levels may be altered in vascular diseases. Larger studies are needed to confirm our results and elucidate the underlying mechanisms.


Assuntos
Isquemia Encefálica/sangue , Lectina de Ligação a Manose da Via do Complemento , Doença das Coronárias/sangue , Serina Proteases Associadas a Proteína de Ligação a Manose/análise , Infarto do Miocárdio/sangue , Doença Aguda , Idoso , Isquemia Encefálica/imunologia , Doença das Coronárias/imunologia , Diabetes Mellitus/sangue , Diabetes Mellitus/epidemiologia , Dislipidemias/sangue , Dislipidemias/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Hipertensão/sangue , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/imunologia , Sobrepeso/sangue , Sobrepeso/epidemiologia , Projetos Piloto , Fatores de Risco , Índice de Gravidade de Doença , Fumar/sangue , Fumar/epidemiologia
4.
Sportverletz Sportschaden ; 27(1): 21-7, 2013 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-23413019

RESUMO

BACKGROUND: The aim of this study is to provide a valid and reliable German version of the Tegner activity scale (Tegner-G). The Tegner activity scale assesses on 11 levels the activity in sports (competitive and recreational) and work of patients with anterior cruciate ligament injuries. The English original version was elaborated in Sweden and contains sports that are unknown in German-speaking countries. METHODS: The translation and adaptation was conducted in several steps according to the guidelines in the literature. The validity (discriminative validity and content validity) and (absolute and relative) reliability were determined in 46 patients after reconstruction of the anterior cruciate ligament and in 20 healthy subjects. The patients were divided into an acute group (< 3 months after operation; 11 men; 30.9 ± 8.3 years) and a chronic group (3 - 12 months after operation; 18 men; 31.3 ± 11.6 years). All subjects filled in the scale two times within 3 - 7 days. For the additional determination of the relation between activity and function, they also filled in the German version of the Lysholm score (Lysholm-G). RESULTS: The three groups differed significantly from each other (Kruskal-Wallis test: χ2 = 27.95, p < 0.001; post hoc Mann-Whitney U tests: acute-chronic p < 0.001; acute-control p < 0.001; chronic-control p = 0.003). There was a floor effect in the acute patient group. The intraclass correlation coefficients indicated a high relative reliability (ICC2,1 > 0.9). The minimal detectable change was 1.4 points. The relation between activity (Tegner-G) and function (Lysholm-G) was stronger in the acute than in the chronic patient group (ρ = 0.77 and ρ = 0.60, respectively). CONCLUSION: The psychometric properties of the Tegner-G are comparable to those of the English original version. The Tegner-G is thus valid and reliable for the German-speaking part of Switzerland. The application in other German-speaking countries probably requires adaptations for some of the sports included. The relation between activity and function changes depending on time since operation. This confirms that a comprehensive assessment of the outcome after an anterior cruciate ligament injury requires the separate assessment of both parameters.


Assuntos
Atividades Cotidianas , Lesões do Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/cirurgia , Traumatismos do Joelho/diagnóstico , Traumatismos do Joelho/cirurgia , Avaliação de Resultados em Cuidados de Saúde/métodos , Índices de Gravidade do Trauma , Adulto , Alemanha , Humanos , Masculino , Recuperação de Função Fisiológica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
5.
N Engl J Med ; 368(7): 610-22, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-23406026

RESUMO

BACKGROUND: Subthalamic stimulation reduces motor disability and improves quality of life in patients with advanced Parkinson's disease who have severe levodopa-induced motor complications. We hypothesized that neurostimulation would be beneficial at an earlier stage of Parkinson's disease. METHODS: In this 2-year trial, we randomly assigned 251 patients with Parkinson's disease and early motor complications (mean age, 52 years; mean duration of disease, 7.5 years) to undergo neurostimulation plus medical therapy or medical therapy alone. The primary end point was quality of life, as assessed with the use of the Parkinson's Disease Questionnaire (PDQ-39) summary index (with scores ranging from 0 to 100 and higher scores indicating worse function). Major secondary outcomes included parkinsonian motor disability, activities of daily living, levodopa-induced motor complications (as assessed with the use of the Unified Parkinson's Disease Rating Scale, parts III, II, and IV, respectively), and time with good mobility and no dyskinesia. RESULTS: For the primary outcome of quality of life, the mean score for the neurostimulation group improved by 7.8 points, and that for the medical-therapy group worsened by 0.2 points (between-group difference in mean change from baseline to 2 years, 8.0 points; P=0.002). Neurostimulation was superior to medical therapy with respect to motor disability (P<0.001), activities of daily living (P<0.001), levodopa-induced motor complications (P<0.001), and time with good mobility and no dyskinesia (P=0.01). Serious adverse events occurred in 54.8% of the patients in the neurostimulation group and in 44.1% of those in the medical-therapy group. Serious adverse events related to surgical implantation or the neurostimulation device occurred in 17.7% of patients. An expert panel confirmed that medical therapy was consistent with practice guidelines for 96.8% of the patients in the neurostimulation group and for 94.5% of those in the medical-therapy group. CONCLUSIONS: Subthalamic stimulation was superior to medical therapy in patients with Parkinson's disease and early motor complications. (Funded by the German Ministry of Research and others; EARLYSTIM ClinicalTrials.gov number, NCT00354133.).


Assuntos
Terapia por Estimulação Elétrica , Doença de Parkinson/terapia , Qualidade de Vida , Atividades Cotidianas , Adulto , Antiparkinsonianos/efeitos adversos , Antiparkinsonianos/uso terapêutico , Terapia Combinada , Agonistas de Dopamina/efeitos adversos , Agonistas de Dopamina/uso terapêutico , Discinesias/etiologia , Terapia por Estimulação Elétrica/efeitos adversos , Feminino , Humanos , Neuroestimuladores Implantáveis/efeitos adversos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Núcleo Subtalâmico , Inquéritos e Questionários , Resultado do Tratamento
6.
Neurology ; 77(9): 888-95, 2011 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-21849650

RESUMO

OBJECTIVE: To examine whether prior statin use affects outcome and intracranial hemorrhage (ICH) rates in stroke patients receiving IV thrombolysis (IVT). METHODS: In a pooled observational study of 11 IVT databases, we compared outcomes between statin users and nonusers. Outcome measures were excellent 3-month outcome (modified Rankin scale 0-1) and ICH in 3 categories. We distinguished all ICHs (ICH(all)), symptomatic ICH based on the criteria of the ECASS-II trial (SICH(ECASS-II)), and symptomatic ICH based on the criteria of the National Institute of Neurological Disorders and Stroke (NINDS) trial (SICH(NINDS)). Unadjusted and adjusted odds ratios (OR) with 95% confidence intervals were calculated. RESULTS: Among 4,012 IVT-treated patients, 918 (22.9%) were statin users. They were older, more often male, and more frequently had hypertension, hypercholesterolemia, diabetes, coronary heart disease, and concomitant antithrombotic use compared with nonusers. Fewer statin users (35.5%) than nonusers (39.7%) reached an excellent 3-month outcome (OR(unadjusted) 0.84 [0.72-0.98], p = 0.02). After adjustment for age, gender, blood pressure, time to thrombolysis, and stroke severity, the association was no longer significant (0.89 [0.74-1.06], p = 0.20). ICH occurred by trend more often in statin users (ICH(all) 20.1% vs 17.4%; SICH(NINDS) 9.2% vs 7.5%; SICH(ECASS-II) 6.9% vs 5.1%). This difference was statistically significant only for SICH(ECASS-II) (OR = 1.38 [1.02-1.87]). After adjustment for age, gender, blood pressure, use of antithrombotics, and stroke severity, the OR(adjusted) for each category of ICH (ICH(all) 1.15 [0.93-1.41]; SICH(ECASS-II) 1.32 [0.94-1.85]; SICH(NINDS) 1.16 [0.87-1.56]) showed no difference between statin users and nonusers. CONCLUSION: In stroke patients receiving IVT, prior statin use was neither an independent predictor of functional outcome nor ICH. It may be considered as an indicator of baseline characteristics that are associated with a less favorable course.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Infusões Intravenosas , Hemorragias Intracranianas/induzido quimicamente , Hemorragias Intracranianas/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Acidente Vascular Cerebral/epidemiologia , Terapia Trombolítica/efeitos adversos , Resultado do Tratamento
7.
Eur J Cell Biol ; 89(10): 769-77, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20656376

RESUMO

Here we demonstrate that physiological concentrations of the thyroid hormones T3 and T4 enhance the KERATIN 15 promoter activity and expression in epithelial stem cells of adult human scalp hair follicles in situ and in vitro. Additionally, T3 and T4 stimulate expression of the immuno-inhibitory surface molecule CD200. Subsequently, T3 and T4 induce apoptosis and differentiation and inhibit clonal growth of these progenitor cells in vitro. These data suggest that human hair follicle bulge-derived epithelial stem cells underlie profound, previously unknown hormonal regulation by thyroid hormones, and show that primary human keratin 15-GFP+ progenitor cells can be exploited to further elucidate fundamental endocrine controls of human epithelial stem cells.


Assuntos
Apoptose/fisiologia , Diferenciação Celular/fisiologia , Células Epiteliais/metabolismo , Folículo Piloso/metabolismo , Queratina-15/metabolismo , Células-Tronco/metabolismo , Tri-Iodotironina/fisiologia , Adulto , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Epiteliais/citologia , Folículo Piloso/citologia , Humanos , Queratina-15/biossíntese , Queratina-15/genética , Técnicas de Cultura de Órgãos , Células-Tronco/citologia , Tiroxina/farmacologia , Tiroxina/fisiologia , Tri-Iodotironina/farmacologia
9.
Phys Rev Lett ; 102(1): 012301, 2009 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-19257182

RESUMO

We report the first measurement of an angular correlation parameter in neutron beta decay using polarized ultracold neutrons (UCN). We utilize UCN with energies below about 200 neV, which we guide and store for approximately 30 s in a Cu decay volume. The interaction of the neutron magnetic dipole moment with a static 7 T field external to the decay volume provides a 420 neV potential energy barrier to the spin state parallel to the field, polarizing the UCN before they pass through an adiabatic fast passage spin flipper and enter a decay volume, situated within a 1 T field in a 2x2pi solenoidal spectrometer. We determine a value for the beta-asymmetry parameter A_{0}=-0.1138+/-0.0046+/-0.0021.

11.
Ann Nutr Metab ; 53(2): 91-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18946205

RESUMO

BACKGROUND: In patients with phenylketonuria (PKU), the carnitine status may be impaired for metabolic or dietary reasons, including low carnitine intake, a deficient synthesis and acylcarnitine production from phenylalanine (Phe) metabolites. METHODS: Free carnitine and acylcarnitine status was assessed in 30 PKU patients, aged 0.5-36 years, mean age 13.8 years. Our cohort was divided into 2 groups according to the preparations of Phe-free amino acids (AA) prescribed, with or without carnitine supplementation. Daily Phe intake, dosage of AA mixtures and body weight were recorded along with measurements of acylcarnitines in blood spots (by tandem mass spectrometry) and serum AA. Control data were obtained from 50 healthy volunteers (aged 0.2-39 years, mean age 14.2. years). Statistical analysis comprised the t test, ANOVA and Pearson's correlation. RESULTS: PKU patients had lower free carnitine (C0) concentrations than controls (25.82 +/- 7.38 vs. 31.28 +/- 6.17 micromol/l; p < 0.001) and lower octanoyl- and decanoylcarnitine. Mean C0 and acylcarnitine concentrations did not differ between PKU patients taking the various protein substitutes with or without carnitine; mean C0 levels in PKU patients receiving AA enriched with carnitine were still lower compared with controls (p < 0.05). CONCLUSIONS: Actual dietary regimens can not completely normalize the carnitine status; therefore, carnitine levels should be given careful consideration in subjects with PKU.


Assuntos
Carnitina/sangue , Carnitina/deficiência , Estado Nutricional , Fenilalanina/administração & dosagem , Fenilcetonúrias/dietoterapia , Adolescente , Adulto , Análise de Variância , Carnitina/administração & dosagem , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Dieta com Restrição de Proteínas , Feminino , Humanos , Lactente , Masculino , Necessidades Nutricionais , Fenilalanina/sangue , Fenilcetonúrias/sangue , Adulto Jovem
12.
J Neurol ; 255(10): 1503-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18677634

RESUMO

BACKGROUND: Comparisons between younger and older stroke patients including comorbidities are limited. METHODS: Prospective data of consecutive patients with first ever acute ischemic stroke were compared between younger (< or = 45 years) and older patients (> 45 years). RESULTS: Among 1004 patients, 137 (14 %) were < or = 45 years. Younger patients were more commonly female (57 % versus 34 %; p < 0.0001), had a lower frequency of diabetes (1 % versus 15 %; p < 0.0001), hypercholesterolemia (26 % versus 56 %; p < 0.0001), hypertension (19 % versus 65 %; p < 0.0001), coronary heart disease (14 % versus 40 %; p < 0.0001), and a lower mean Charlson co-morbidity index (CCI), (0.18 versus 0.84; p < 0.0001). Tobacco use was more prevalent in the young (39 % versus 26 %; P < 0.0001). Large artery disease (2 % versus 21 %; p < 0.0001), small artery disease (3 % versus 12 %; p = 0.0019) and atrial fibrillation (1 % versus 17 %; p = 0.001) were less common in young patients, while other etiologies (31 % versus 9 %; p < 0.0001), patent foramen ovale or atrial septal defect (44 % versus 26 %; p < 0.0001), and cervical artery dissection (26 % versus 7 %; p < 0.0001) were more frequent. A favorable outcome (mRS 0 or 1) was more common (57.4 % versus 46.9 %; p = 0.023), and mortality (5.1 % versus 12 %; p = 0.009) was lower in the young. After regression analysis, there was no independent association between age and outcome (p = 0.206) or mortality (p = 0.073). Baseline NIHSS score (p < 0.0001), diabetes (p = 0.041), and CCI (p = 0.002) independently predicted an unfavorable outcome. CONCLUSIONS: Younger patients were more likely to be female, had different risk factors and etiologies and fewer co-morbidities. There was no independent association between age and clinical outcome or mortality.


Assuntos
Isquemia/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Doença Aguda/epidemiologia , Adulto , Fatores Etários , Comorbidade , Demografia , Feminino , Humanos , Isquemia/etiologia , Isquemia/terapia , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Análise de Regressão , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Resultado do Tratamento
13.
Dtsch Med Wochenschr ; 132(27): 1469-74, 2007 Jul 29.
Artigo em Alemão | MEDLINE | ID: mdl-17583831

RESUMO

Pernicious anemia and Vitamin B12 deficiency have a wide range of symptoms and are a common finding in the elderly. A 73 year old female is admitted to the hospital because of dyspnea, fatigue and loss of appetite and weight. While previous medical history and physical examination are inconspicuous, laboratory findings show severe pancytopenia with macrocytosis, low reticulocyte count and marked signs of hemolysis. A very low serum level of vitamin B12 and chronic atrophic type A gastritis upon endoscopy with presence of parietal cell antibodies in the serum lead to the diagnosis of pernicious anemia. Complete restitution is achieved by parenteral vitamin B12 substitution. Nowadays, severe pernicious anemia is only rarely seen. The differential diagnosis of pancytopenia (with macrocytic anemia) combined with hemolysis and the essential hints to the diagnosis of pernicious anemia are discussed, and thereby practical aspects including therapy actualized.


Assuntos
Anemia Perniciosa/diagnóstico , Pancitopenia/diagnóstico , Vitamina B 12/uso terapêutico , Fatores Etários , Idoso , Anemia Macrocítica/sangue , Anemia Macrocítica/diagnóstico , Anemia Perniciosa/sangue , Diagnóstico Diferencial , Feminino , Ácido Fólico/administração & dosagem , Gastrite Atrófica/diagnóstico , Hemólise , Humanos , L-Lactato Desidrogenase/sangue , Pancitopenia/sangue , Vitamina B 12/administração & dosagem , Vitamina B 12/sangue
14.
Int J Oral Maxillofac Surg ; 32(6): 600-5, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14636609

RESUMO

Computed radiography (CR) provides the dynamic exposure range to reveal objects in film areas exposed by very low X-ray exposure. Conventional cephalometric radiographs are normally beam limited to the facial skeleton. The cranial vault and cervical vertebra are collimated and only exposed by extra-focal radiation and scatter. We hypothesize that, on conventional cephalometric radiographs obtained with CR, image data of collimated film areas can be enhanced for reliable performance of Delaire's cephalometric analysis of the entire skull. Therefore the aim of the present study was to compare the reproducibility of landmark placement on normal and underexposed film areas of CR images. Intra- and inter-observer reproducibility of landmark identification was evaluated on 200 randomly selected radiographs by calculating the error radius of repeated landmark placements. A paired-samples t-test revealed differences (P< 0.001) between intra- and inter-observer reproducibility. Intra-observer accuracy was influenced (P< 0.001) by variability of suture obliteration (bregma). Identification of landmarks in areas of extra-focal radiation showed no difference (P> 0.05) from that of landmarks inside the normally exposed area. CR offers the opportunity to perform of a full cranial analysis on a cephalometric radiograph collimated to the facial region.


Assuntos
Cefalometria/métodos , Radiografia Dentária Digital , Humanos , Variações Dependentes do Observador , Imagens de Fantasmas , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos
15.
Br J Oral Maxillofac Surg ; 41(2): 102-8, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12694702

RESUMO

The survival of loaded implants is critically dependent on their biomechanical stability. We have used a computer-guided navigation technique to evaluate the accuracy of computer-assisted insertion for immediately-loaded implants in minipigs. On the basis of computed tomographical data, the Robodent system was used for preoperative planning and guidance of inserting the implant. An optical tracking system allowed positioning of the implant and immediate prosthetic rehabilitation by inserting it in a plaster model and during the operation. Postoperative computed tomograms (CT) showed that the implants were placed precisely in the preoperatively planned position. The accuracy achieved corresponded well with the spatial resolution of the CT used. Immediate placement of the prefabricated crowns resulted in favourable occlusal positioning. Histological cross-sections showed that the implants were biomechanically stable. The accuracy of insertion of oral implants illustrated here suggests that insertion and prosthetic modelling of implants may benefit from computer-assisted navigation.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Prótese Dentária Fixada por Implante , Cirurgia Assistida por Computador , Animais , Fenômenos Biomecânicos , Coroas , Dente Suporte , Planejamento de Prótese Dentária , Masculino , Mandíbula/cirurgia , Microscopia Eletrônica de Varredura , Modelos Dentários , Osseointegração , Planejamento de Assistência ao Paciente , Cirurgia Assistida por Computador/instrumentação , Cirurgia Assistida por Computador/métodos , Suínos , Porco Miniatura , Tomografia Computadorizada por Raios X
16.
Rofo ; 175(1): 112-7, 2003 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-12525991

RESUMO

PURPOSE: To evaluate a possible dose reduction in pediatric pelvic radiographs in congenital hip dysplasia using a digital flat-panel system instead of a phosphor-storage system. MATERIALS AND METHODS: During a six-month period, all pediatric patients referred for pelvic radiography for the evaluation of congenital hip dysplasia were randomly assigned to be examined by either a phosphor-storage system or a digital flat-panel system, whereby the latter system was operated with half the radiation dose. Thirty pairs of radiographs were assessed for the visibility of 16 anatomic details and for 5 orthopedic-radiographic measurements (5-point scale with 1 = excellent; three independent observers). The projection indices of Ball and Kommenda and of Tönnis and Brunken were calculated for all radiographs. The Student's t-test was used to compare the flat-panel and the phosphor-storage radiographs for observers' assessments, patients' age and projection indices. RESULTS: In a total of 7560 observations, the scores for the visibility of anatomic details and orthopedic-radiographic measurements were respectively 2.72 and 2.64 for the flat-panel system and 2.93 and 2.79 for the phosphor-storage system. No significant differences were found between both systems (p > 0.05) and between patient age and projection indices (p > 0.05). CONCLUSION: Pediatric pelvic radiographs can be obtained with a digital flat-panel system using half the radiation dose instead of a phosphor-storage system without sacrificing relevant information in the diagnosis of congenital hip dysplasia.


Assuntos
Luxação Congênita de Quadril/diagnóstico por imagem , Proteção Radiológica , Intensificação de Imagem Radiográfica/métodos , Fatores Etários , Criança , Pré-Escolar , Interpretação Estatística de Dados , Humanos , Lactente , Doses de Radiação
17.
Calcif Tissue Int ; 72(2): 156-65, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12370799

RESUMO

The purpose of this study was to use high resolution magnetic resonance imaging (HR-MRI) combined with structure analysis to investigate the trabecular structure of the human proximal femur and to compare this technique with bone mineral density (BMD) using dual energy X-ray absorptiometry (DXA) in the prediction of bone strength in vitro. Thirty-one fresh human proximal femur specimens were examined with HR-MRI using a T1-weighted 3D spinecho-sequence in a coronal plane (voxel size: 0.195 x 0.195 x 0.9 mm and 0.195 x 0.195 x 0.3 mm). In these images structure parameters analogous to standard bone histomorphometry were obtained in a femoral head, neck, and trochanteric region of interest (ROI). In addition, BMD measurements were obtained using DXA and finally, all specimens were tested biomechanically in a materials testing machine, and maximum compressive strength (MCS) was determined. Correlations between BMD and MCS were significant (p <0.01) with R-values up to 0.74. Correlating structure parameters and MCS R-values up to 0.69 (P <0.01) were obtained. Using multivariate regression analysis, combining structure parameters and BMD, improved correlations versus MCS substantially (up to R = 0.93; P <0.01). In conclusion, this study showed that in an experimental setting, structure parameters determined in high resolution MR images of the proximal femur correlated significantly with bone strength. The highest correlations, however, were obtained combining BMD and structure measures.


Assuntos
Fêmur/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Idoso , Densidade Óssea , Osso e Ossos/anatomia & histologia , Osso e Ossos/diagnóstico por imagem , Força Compressiva , Feminino , Fêmur/diagnóstico por imagem , Fêmur/fisiologia , Humanos , Masculino , Radiografia , População Branca
18.
Br J Oral Maxillofac Surg ; 40(2): 96-104, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12180219

RESUMO

The outcome of complex craniofacial operations is critically dependent on careful and accurate preoperative planning. Recent advances in computer technology enable the surgeon to do surgical simulations directly on to a computer terminal. We describe the clinical application of a public domain-based computer-aided system in craniofacial surgery. Operation planning was based on clinical investigations and radiological images, with particular use of a virtual three-dimensional surgical simulation. Three patients with complex craniofacial malformations were admitted for orbital correction. Surgical simulation defined numerically the extent of bone movements and the extent of resection areas. Operations were guided by the virtual planning. The outcome was compared with the planning to assess the accuracy of the operative correction. Our first experience confirms that computer-assisted simulation is a reliable and useful tool that improves surgical planning and helps to evaluate the surgical outcome.


Assuntos
Simulação por Computador , Anormalidades Craniofaciais/cirurgia , Craniotomia/métodos , Procedimentos de Cirurgia Plástica/métodos , Cirurgia Assistida por Computador , Adulto , Cefalometria , Pré-Escolar , Feminino , Humanos , Imageamento Tridimensional , Microftalmia/cirurgia , Órbita/anormalidades , Planejamento de Assistência ao Paciente , Setor Público , Software , Tomografia Computadorizada por Raios X , Interface Usuário-Computador
19.
Rofo ; 173(12): 1099-103, 2001 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-11740670

RESUMO

PURPOSE: In the present study the reduction of artifacts using an extended CT scale technique was examined in 5 vitallium and 5 titanium-aluminium-vanadium tumor prostheses. METHODS: 5 titanium-aluminium-vanadium and 5 vitallium distal femur Mutars(R) tumor prostheses (Mutars(R) - Modular Universal Tumor And Revision System) were implanted in 10 human femur specimens. 110 artifical drill hole lesions of 1 mm, 2 mm, 3 mm, 5 mm and 8 mm diameter were placed in the bone around the hexagonal stem of the tumor prosthesis and furthermore in the proximal part of the femur. All specimens were examined using conventional CT and an extended CT scale technique in a slice thickness of 3 mm. RESULTS: In the proximal part of the femur all drill holes could be detected using 3 mm slices, no artefacts were observed. Along the hexagonal stem smooth lines arising from each hexagonal plane could be observed. This made it impossible to detect a 1 mm drill in 1 vitallium and in 1 titanium-aluminium-vanadium stem. There was no difference between the extended CT scale and conventional CT. CONCLUSION: The extended CT scale did not significantly (p > 0.05, t-test) improve the imaging of artificial drill hole lesions along the hexagonal Mutras(R) stem.


Assuntos
Neoplasias Ósseas/cirurgia , Neoplasias Femorais/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Implantação de Prótese , Tíbia/cirurgia , Titânio , Tomografia Computadorizada por Raios X , Vitálio , Idoso , Idoso de 80 Anos ou mais , Ligas , Artefatos , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Femorais/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Desenho de Prótese , Intensificação de Imagem Radiográfica , Sensibilidade e Especificidade , Tíbia/diagnóstico por imagem
20.
Nuklearmedizin ; 40(6): 193-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11797507

RESUMO

PURPOSE: To retrospectively evaluate FDG accumulations in major joints in a large series of non-absorption corrected partial body and whole body FDG-PET scans, and to determine the frequency and intensity of accumulation. MATERIALS AND METHODS: 354 consecutive PET partial- and whole body non-transmission corrected scans of patients obtained for tumor staging were examined with respect to FDG accumulations in the acromio-clavicular (AC)-, gleno-humeral-, hip-, knee- and talo-tibial joints. FDG-uptake was graded using a semi-quantitative scale from 0 (no accumulation) to 4 (very strong accumulation comparable to brain uptake). RESULTS: Joint activity of grade 1-2 was noted frequently, while grade 3 was rare, occurring only in the knee and shoulder joints, and grade 4 was inexistent. The 43 patients with grade 3 accumulations or with at least 4 joints showing grade 2 uptake were interviewed, but all denied pain specifically referred to a joint. Joint accumulations were seen in 50% of the acromio-clavicular-, 80% in the glenohumeral-, 50% in the hip-, 90% in the knee and 80% in the talo-tibial joints. The intensities of joint accumulations correlated positively and significantly with patient age, ranging from r = 0.7 and p < 0.05 in the knee to r = 0.96 and p < 0.0001 in the AC joint. CONCLUSIONS: FDG accumulations in the joints in whole body FDG-PET scans are frequent and are very likely not related to symptoms. As there is a strong age correlation, and FDG is known to accumulate in inflammatory lesions, the findings are most likely a result of sub-clinical inflammatory synovial proliferation or other chronic inflammatory processes occurring in aging joints.


Assuntos
Fluordesoxiglucose F18/farmacocinética , Neoplasias/diagnóstico por imagem , Compostos Radiofarmacêuticos/farmacocinética , Tomografia Computadorizada de Emissão , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transporte Biológico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Articulações/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/patologia , Distribuição Tecidual
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