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1.
Osteoarthritis Cartilage ; 11(7): 494-8, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12814612

RESUMO

OBJECTIVES: The aim of the study was to detect cartilage defects and determine the center of these defects in MR imaging of the patellofemoral joint (PFJ) in middle-aged people with chronic knee pain. DESIGN: In the format of a prospective study of early osteoarthritis (OA), this cross-sectional study of the signal knee (the most painful one at inclusion in the study in 1990) in 59 individuals, 30 women and 29 men (aged 41-58 years, mean 50 years) with chronic knee pain, with or without radiographically determined knee OA, was examined using MR imaging on a 1.0 T imager. Cartilage defects and the center of these defects in the PFJ were recorded. RESULTS: Cartilage defects were found more often in the patella (40 knees) than in the femoral trochlea (23 knees) (P<0.001) and were unevenly distributed in the patella (P<0.001), with most cartilage defects in the mid-patella. CONCLUSIONS: Since cartilage defects occur more commonly in the mid-patella, radiographs obtained with a knee flexion of approximately 45 degrees may be more accurate to show cartilage defects of early OA of the PFJ than views with another knee flexion.


Assuntos
Doenças das Cartilagens/diagnóstico , Osteoartrite do Joelho/diagnóstico , Dor/diagnóstico , Adulto , Estudos Transversais , Feminino , Humanos , Articulação do Joelho , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
2.
Osteoarthritis Cartilage ; 11(5): 370-6, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12744943

RESUMO

OBJECTIVES: To assess the interval change of the minimal joint space width (MJS) in radiographs of the tibiofemoral (TF) joint and of the patellofemoral (PF) joint with a 2-year follow-up in middle-aged people with longstanding knee pain with or without radiographic osteoarthritis (OA) and to study the precision of the MJS measurements. DESIGN: In the format of a prospective study of early OA the signal knee in 55 people, 28 men and 27 women (aged 41-57 years, median 50), with chronic knee pain at inclusion was examined with a 2-year interval (median 25 months, range 21-30). The MJS of the TF joint was measured using a flexed PA view in weightbearing and the MJS of the PF joint using an axial view in standing. RESULTS: The MJS of the TF joint decreased medially by 0.056+/-0.44mm (n.s.) and increased laterally by 0.080+/-0.51mm (n.s.) during the time of observation. In knees with an MJS medially that was less or the same as compared with the lateral compartment, the MJS decreased by 0.14+/-0.38mm (p=0.038) and in a subgroup of these knees, without osteophytes, the MJS decreased by 0.14+/-0.27mm (p=0.018). The MJS of the PF joint decreased by 0.019mm (n.s.) during the time of observation. The coefficient of variation for intra- and interobserver MJS measurements of the TF joint was 1.0 and 1.1% medially and 2.3 and 2.7% laterally, and for measurement error 6.9% medially and 4.8% laterally, respectively. The coefficient of variation for intra- and interobserver MJS measurements of the PF joint was 8.1 and 5.8% medially and 7.5 and 10.1% laterally and for the measurement error it was 8.1% medially and 8.5% laterally, respectively. CONCLUSIONS: A statistically significant reduction of the MJS was only demonstrated in the medial compartment of the TF joint in those individuals who had an MJS in this compartment which was less or the same as compared with the lateral compartment as well as in a subgroup of these knees without osteophytes. The radiographic examinations and the MJS measurements were reproducible.


Assuntos
Articulação do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/diagnóstico por imagem , Dor/diagnóstico por imagem , Adulto , Progressão da Doença , Feminino , Seguimentos , Humanos , Articulação do Joelho/patologia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/patologia , Dor/patologia , Estudos Prospectivos , Radiografia
3.
Osteoarthritis Cartilage ; 9(5): 473-80, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11467896

RESUMO

OBJECTIVE: The aim of the study was to evaluate the change over time of cartilage defects, subchondral lesions and meniscal abnormalities of the knee using magnetic resonance (MR) imaging with a 2-year interval in patients with chronic knee pain. DESIGN: In the format of a prospective study of early osteoarthritis (OA), the signal knee (most painful at the inclusion in the study 1990) in 47 individuals, 25 women and 22 men (aged 41-57 years, median 50), with chronic knee pain, with or without radiographically determined knee OA, were examined using MR imaging on a 1.0 T imager with a 2-year interval (median 25 months, range 21-30). Cartilage defects, subchondral lesions and meniscal abnormalities were recorded and compared in blind between the examinations. RESULTS: Five new cartilage defects and eight subchondral lesions appeared during the 2-year interval. Seven defects and seven subchondral lesions disappeared during the same time. Thirty-two out of 93 cartilage defects (34%) and 19 out of 32 subchondral lesions (59%) displayed an increase or a decrease in size over time. A meniscal abnormality appeared in three locations, and disappeared in none. In 14 out of 54 locations (26%) with a meniscal abnormality an increase or a decrease of the abnormality was recorded over time and no abnormality decreased. CONCLUSIONS: After the 2 years of observation it was possible to register, using MR imaging, the appearance, increase, decrease and disappearance of cartilage defects, subchondral lesions and meniscal abnormalities in middle-aged people with chronic knee pain. This has to be considered in studies of the natural course of knee OA as well as in studies of the intraarticular effect of pharmacological treatment aiming at cartilage repair or protection.


Assuntos
Cartilagem Articular/patologia , Articulação do Joelho , Osteoartrite do Joelho/patologia , Dor/patologia , Adulto , Doença Crônica , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
4.
Ann Rheum Dis ; 58(1): 20-6, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10343536

RESUMO

OBJECTIVE: To compare increased bone uptake of 99Tcm-MDP and magnetic resonance (MR) detected subchondral lesions, osteophytes, and cartilage defects in the knee in middle aged people with long-standing knee pain. METHODS: Fifty eight people (aged 41-58 years, mean 50) with chronic knee pain, with or without radiographic knee osteoarthritis, were examined with bone scintigraphy. The pattern and the grade of increased bone uptake was assessed. On the same day, a MR examination on a 1.0 T imager was performed. The presence and the grade of subchondral lesions, osteophytes, and cartilage defects were registered. RESULTS: The kappa values describing the correlation between increased bone uptake and MR detected subchondral lesions varied between 0.79 and 0.49, and between increased bone uptake and MR detected osteophytes or cartilage defects the values were < 0.54. The kappa values describing the correlation between the grade of bone uptake and the grade of the different MR findings was < 0.57. CONCLUSIONS: Good agreement was found between increased bone uptake and MR detected subchondral lesion. The agreement between increased bone uptake and osteophytes or cartilage defects was in general poor as well as the agreement between the grade of bone uptake and the grade of the MR findings.


Assuntos
Osteoartrite do Joelho/diagnóstico , Adulto , Cartilagem Articular/patologia , Feminino , Fêmur/diagnóstico por imagem , Seguimentos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Patela/diagnóstico por imagem , Estudos Prospectivos , Cintilografia , Compostos Radiofarmacêuticos , Medronato de Tecnécio Tc 99m , Tíbia/diagnóstico por imagem
5.
Ann Rheum Dis ; 57(7): 395-400, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9797565

RESUMO

OBJECTIVE: To assess the correlation between radiographically diagnosed osteophytes in the axial and lateral view of the patellofemoral joint (PFJ) and (1) magnetic resonance (MR) detected cartilage defects in the same joint and (2) knee pain. METHODS: Fifty-seven people with chronic knee pain, (aged 41-58 years, mean 50 years) were examined with axial and lateral radiograms when standing of the right and the left PFJ. The presence and grade of osteophytes was assessed. On the same day, a MR examination was performed of the signal knee with proton density and T2 weighted turbo spin-echo sequences in the sagittal and axial view on a 1.0 T imager. Cartilage defects in the PFJ were noted. The subjects were questioned for current knee pain for each knee. RESULTS: Osteophytes at the PFJ had a specificity varying between 59 and 100% and a positive predictive value between 74 and 100% for MR detected cartilage defects. The corresponding values for osteophytes at the lateral aspect of the femoral trochlea were both 100%. In PFJ with narrowing (< 5 mm) osteophytes had a sensitivity and a positive predictive value of 90 and 95% respectively for MR detected cartilage defects, while in PFJ with non-narrowing (> or = 5 mm) the corresponding values were 75 and 65% and the specificity was 50%. A correlation (p < 0.05) between osteophytes at the inferior pole of the patella and knee pain was found. CONCLUSIONS: Osteophytes at the PFJ are associated with MR detected cartilage defects in the same joint. The relation was strong for osteophytes at the lateral femoral trochlea and in the PFJ with narrowing (< 5 mm), but weak in the PFJ with non-narrowing (> or = 5 mm).


Assuntos
Osso e Ossos/patologia , Cartilagem Articular/patologia , Articulação do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/diagnóstico , Adulto , Osso e Ossos/diagnóstico por imagem , Doenças das Cartilagens/diagnóstico , Doenças das Cartilagens/diagnóstico por imagem , Doença Crônica , Feminino , Fêmur , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Dor/diagnóstico por imagem , Dor/patologia , Patela , Estudos Prospectivos , Radiografia
6.
Ann Rheum Dis ; 57(7): 401-7, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9797566

RESUMO

OBJECTIVE: To assess the correlation between the presence of radiographically diagnosed osteophytes in the tibiofemoral joint (TFJ) and (1) magnetic resonance (MR) detected cartilage defects and meniscal lesions in the same joint and (2) knee pain. METHODS: Fifty-nine people, 29 men and 30 women, with chronic knee pain (aged 41-58 years, mean 50 years) were examined with posteroanterior weightbearing radiograms in semiflexion of both TFJ. The presence and grade of marginal and central osteophytes were assessed. On the same day, an MR examination was performed of the signal knee with proton density and T2 weighted turbo spin-echo sequences on a 1.0 T imager. Cartilage defects and meniscal abnormalities in the TFJ were noted. The subjects were questioned for current knee pain for each knee. RESULTS: Marginal osteophytes had a sensitivity of 77%, specificity of 83%, and positive predictive value of 87% for MR detected cartilage defects in the TFJ and a sensitivity of 71%, specificity of 68%, and positive predictive value of 71% for meniscal abnormalities. A correlation (p < 0.05) between osteophytes at the medial tibial condyle and knee pain was found. CONCLUSIONS: With the presence of marginal osteophytes in the TFJ there is a high prevalence of MR detected cartilage defects in the same joint whether joint space narrowing (< 3 mm) is present or not.


Assuntos
Osso e Ossos/patologia , Doenças das Cartilagens/diagnóstico , Articulação do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/diagnóstico por imagem , Dor/diagnóstico por imagem , Adulto , Osso e Ossos/diagnóstico por imagem , Doenças das Cartilagens/diagnóstico por imagem , Doença Crônica , Feminino , Fêmur , Seguimentos , Humanos , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico , Dor/patologia , Valor Preditivo dos Testes , Estudos Prospectivos , Radiografia , Sensibilidade e Especificidade , Tíbia
7.
Acta Radiol ; 39(1): 24-31, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9498865

RESUMO

PURPOSE: To validate a bony landmark on the dorsal aspect of the patella for measurement of the interbone distance in the axial radiogram of the patello-femoral joint (PFJ); to assess the reproducibility of this radiogram and the minimal joint-space (MJS) width measurements in the medial and lateral compartments of the PFJ in this view; and to relate the MJS of the PFJ to MR-detected cartilage defects in the same joint. MATERIAL AND METHODS: Fifty-seven individuals with chronic knee pain (aged 41-58 years, mean 50 years) were examined with an axial view of the PFJ in the standing position. The MJS was measured with a mm-graded ruler. On the same day, an MR examination was performed with proton density- and T2-weighted turbo spin-echo sequences on a 1.0 T imager. We noted the cartilage defects in the PFJ in axial and sagittal MR images, and the shape of the subchondral cortex of the medial and lateral articular surfaces of the patella in sagittal MR images. RESULTS AND CONCLUSION: The bony landmark was found on all articular surfaces. The axial view of the PFJ and the MJS measurements were reproducible. An MJS of <5 mm showed high specificity for MR-detected cartilage defects. Thus an MJS of 5 mm proved to be a limit in the diagnosis of joint-space narrowing in the PFJ in middle-aged individuals with chronic knee pain.


Assuntos
Artralgia/diagnóstico , Fêmur , Articulação do Joelho , Patela , Adulto , Artralgia/epidemiologia , Artralgia/etiologia , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia , Doença Crônica , Feminino , Fêmur/diagnóstico por imagem , Fêmur/patologia , Seguimentos , Humanos , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Patela/diagnóstico por imagem , Patela/patologia , Estudos Prospectivos , Radiografia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Inquéritos e Questionários , Suécia/epidemiologia
8.
Acta Radiol ; 39(1): 32-5, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9498866

RESUMO

PURPOSE: The aim of the study was to compare the minimal joint-space (MJS) width of the tibiofemoral joint (TFJ) in weight-bearing radiograms with the patient in two different positions. MATERIAL AND METHODS: From a study of 54 patients with chronic knee pain (aged 42-59 years, mean 52 years), we selected 21 consecutive patients for this study. In these 21 patients, both knees were examined by means of p.a. weight-bearing radiograms in semiflexion with fluoroscopic guidance. The patient stood with the weight: 1) almost entirely on the examined leg; and 2) equally distributed on both legs. The MJS was measured with a scale loupe in tenths of a millimeter in the medial and lateral compartments of the TFJ. RESULTS: With the patient standing on one leg, the MJS was 0.18 mm wider (p<0.006) in the medial compartment and 0.18 mm narrower (p<0.029) in the lateral compartment as compared to standing on both legs. CONCLUSION: With the technique used, the assessment of the MJS width in the p.a. view of the TFJ in weight-bearing examinations should be performed with equal weight on both legs. Standing on only the examined leg might be an option in cases of suspected narrowing in the lateral compartment.


Assuntos
Artralgia/diagnóstico por imagem , Fêmur/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Suporte de Carga , Adulto , Artralgia/fisiopatologia , Doença Crônica , Feminino , Seguimentos , Humanos , Articulação do Joelho/fisiopatologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos , Radiografia , Amplitude de Movimento Articular , Reprodutibilidade dos Testes
9.
Acta Radiol ; 38(6): 1063-70, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9394671

RESUMO

PURPOSE: The purpose was four-fold: to assess the reproducibility of p.a. weight-bearing radiograms of the knee and the minimal joint-space (MJS) width measurements in these radiograms; to compare the MJS with MR-detected cartilage defects; to evaluate the location of these cartilage defects; and to estimate the relation between meniscal abnormalities and joint-space narrowing. MATERIAL AND METHODS: Fifty-nine individuals, aged 41-58 years (mean 50), with chronic knee pain were examined by means of p.a. weight-bearing radiograms in semiflexion with fluoroscopic guidance of the knee joint. The MJS was measured with a standard ruler. On the same day MR imaging was performed with proton-density- and T2-weighted turbo spin-echo on a 1.0 T imager. Meniscal abnormalities and cartilage defects in the tibiofemoral joint (TFJ) were noted. RESULTS AND CONCLUSION: The p.a. view of the knee and the MJS measurements were reproducible. MJS of 3 mm is a limit in diagnosing joint-space narrowing in knees with MR-detected cartilage defects. There was a high proportion (p < 0.001) of meniscal abnormality within the narrowed compartments in comparison with those that were not narrowed. A larger number of the cartilage defects (p < 0.05) was found in the medial femoral condyle than in any of the other condyles of the TFJ. The defects had a dorsal location (p < 0.001) as shown in the weight-bearing radiograms of the knee in semiflexion.


Assuntos
Articulação do Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética , Amplitude de Movimento Articular , Suporte de Carga , Adulto , Doenças das Cartilagens/diagnóstico , Doenças das Cartilagens/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia , Doença Crônica , Feminino , Fêmur/diagnóstico por imagem , Fêmur/patologia , Fluoroscopia , Humanos , Artropatias/diagnóstico , Artropatias/diagnóstico por imagem , Articulação do Joelho/patologia , Masculino , Meniscos Tibiais/diagnóstico por imagem , Meniscos Tibiais/patologia , Pessoa de Meia-Idade , Dor/diagnóstico , Dor/diagnóstico por imagem , Reprodutibilidade dos Testes , Tíbia/diagnóstico por imagem , Tíbia/patologia
10.
Acta Radiol ; 37(6): 877-82, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8995458

RESUMO

PURPOSE: To evaluate the occurrence and extent of Gd-DTPA-enhanced synovial structures in asymptomatic knee joints of middle-aged healthy individuals. MATERIAL AND METHODS: MR imaging of the knee joint was performed in 10 healthy subjects aged 40-61 years. The study included a sagittal T1-weighted SE sequence before and after i.v. injection of 0.1 mmol Gd-DTPA/kg b.w. RESULTS: Contrast-enhanced synovial structures were found in all knees. The extent of the synovial structures was usually not uniform within the examined joint. In the intercondylar fossa, the thickness of synovial structures was more often pronounced. In the suprapatellar recess, synovial thickness was constant and minimal. CONCLUSION: The presence and the varying extent and thickness of synovial structures in asymptomatic knees in middle-aged individuals must be considered in the evaluation of early and mild synovitis of the knee joint with Gd-enhanced MR imaging in this age group.


Assuntos
Meios de Contraste , Gadolínio , Articulação do Joelho/anatomia & histologia , Imageamento por Ressonância Magnética , Compostos Organometálicos , Ácido Pentético/análogos & derivados , Adulto , Feminino , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Membrana Sinovial/anatomia & histologia , Sinovite/diagnóstico
11.
Skeletal Radiol ; 25(7): 655-60, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8915050

RESUMO

OBJECTIVE: To identify radiological changes of the hands and feet in a large group of patients with Laurence-Moon-Bardet-Biedl syndrome. DESIGN: Postero-anterior views of hands and feet were obtained and analysed. PATIENTS: The material consists of 43 Scandinavian patients with the syndrome (24 males and 19 females; age 3 weeks to 57 years, median 23 years at the time of radiological examination). RESULTS AND CONCLUSIONS: Polydactyly of the hands and feet is one of the main criteria. This was noted clinically in 33 of 43 patients, but all but 3 had been operated on before this radiological study. Remnants of the extirpated finger or toe noted as exostoses, additional joint surfaces of duplication were found in half the hands and feet, while the remainder showed no radiological changes. Other features found were short, broad bones and flat joint surfaces of the metacarpophalangeal or metatarsophalangeal joints. We also found a high frequency of short or long ulna in relation to the radius and Madelung deformity of the wrist in several patients. Thus, the radiographs showed several non-specific normal variations besides remnants or postoperative changes after polydactyly.


Assuntos
Osso e Ossos/diagnóstico por imagem , Deformidades Congênitas do Pé/diagnóstico por imagem , Deformidades Congênitas da Mão/diagnóstico por imagem , Síndrome de Laurence-Moon/diagnóstico por imagem , Adolescente , Adulto , Osso e Ossos/anormalidades , Criança , Pré-Escolar , Feminino , Deformidades Congênitas do Pé/complicações , Deformidades Congênitas da Mão/complicações , Humanos , Lactente , Recém-Nascido , Síndrome de Laurence-Moon/complicações , Masculino , Pessoa de Meia-Idade , Radiografia
12.
Eur Heart J ; 17(7): 1103-11, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8809529

RESUMO

Transoesophageal echocardiography renders a better image than transthoracic echocardiography of cardiac changes especially at the atrial level, and of atherosclerotic changes in the aorta. Although several studies on stroke patients have included transthoracic and transoesophageal echocardiography, the relevance of the reported findings remains unclear because of limited information on the prevalence of cardiac changes related to cardioembolism in a control population without stroke. In order to define a non-hospitalized group of volunteers without previous stroke or transient ischaemic attack, we randomly selected a group of 68 volunteers (mean age 65.4 years). These volunteers were divided into two groups: the elderly group, 65 years or older (n = 38) and the younger group, younger than 65 years (n = 30). The subjects underwent transthoracic and transoesophageal echocardiography, sonography of the carotid arteries, and magnetic resonance imaging of the brain. The prevalences of atrial septal aneurysm, patent foramen ovale, mitral annulus calcification, and protruding plaque in the aorta were investigated. We found atrial septal aneurysm in 13%, patent foramen ovale in 22%, protruding plaque in the aorta in 7%, and mitral annular calcification in 22% of the 68 subjects. No significant differences were found between the two age groups with the exception of mitral annular calcification, which was seen more often in the older group (P < 0.001). Total cardiac changes related to thromboembolism (including three cases with atrial fibrillation in the older group and other less common cardiac embolic sources) were more common in the older than in the younger group (23/38 vs 9/30; P < 0.05). If mitral annular calcification was excluded, no difference was found between the elderly and the younger group, 14/38 vs 8/30; ns. Even when subjects with a history of heart disease or a pathological ECG were omitted, no differences between the two age groups were found. The causal relationship between a possible embolic source and a clinical embolic event remains unsettled. The high prevalence of cardiac changes in a control population has to be considered when evaluating the significance of similar findings in patients with stroke.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Transtornos Cerebrovasculares/etiologia , Ecocardiografia Transesofagiana/métodos , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Artérias Carótidas/fisiopatologia , Transtornos Cerebrovasculares/diagnóstico , Distribuição de Qui-Quadrado , Feminino , Humanos , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Distribuição Aleatória , Valores de Referência , Sensibilidade e Especificidade
13.
Acta Radiol ; 37(4): 555-60, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8688242

RESUMO

PURPOSE: To investigate the spatial resolution requirements in digital radiography of scaphoid fractures. MATERIAL AND METHODS: Included in the study were 60 scaphoid radiographs with and 60 without fractures of the scaphoid bone. The film-screen images were digitized using pixel sizes of 115, 170, and 340 microns along with 170 microns with a 10:1 wavelet compression. The digital images were displayed on a 1280 x 1024 x 8 bits monitor, and 5 observers evaluated the images in 5 randomized sessions. The results for each pixel size were then compared to the film-screen images by ROC analysis. RESULTS: The mean area under the ROC curves was larger for the film-screen images than for the digital images at all resolutions. However, this difference was not significant when the areas under the ROC curves for the film-screen images were compared to the digital images of 115, 170, and 170 microns with 10:1 compression. There was a significant difference for the 340-microns pixel size in favour of the film-screen images. The mean ROC curves for the digital images were very similar for the 115 and 170 microns pixel sizes, although slightly better for 115 microns. At 170 microns, the compression seemed to have a relatively small negative effect on the diagnostic performance; the deterioration was greater when the pixel size was increased to 340 microns. There was no obvious correlation between diagnostic performance and the experience of the observers in using work-stations. CONCLUSIONS: The pixel size of 170 microns is adequate for the detection of subtle fractures, even after wavelet compression by a ratio of 10:1.


Assuntos
Angiografia Digital , Ossos do Carpo/diagnóstico por imagem , Ossos do Carpo/lesões , Fraturas Ósseas/diagnóstico por imagem , Humanos , Curva ROC , Ecrans Intensificadores para Raios X
14.
Stroke ; 25(7): 1371-7, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8023352

RESUMO

BACKGROUND AND PURPOSE: To determine how a recently proposed clinical stroke subclassification corresponds to specific findings on computed tomography (CT) and magnetic resonance imaging (MRI) of the brain. METHODS: Two hundred twenty-eight patients with first-ever stroke were divided into four clinical subgroups: (1) total anterior circulation syndrome: both cortical and subcortical symptoms from anterior and middle cerebral artery territory; (2) partial anterior circulation syndrome: more restricted and predominantly cortical symptoms from the same arterial territories; (3) lacunar syndrome; and (4) posterior circulation syndrome: vertebrobasilar or posterior cerebral artery symptoms. The imaging protocol included CT of the brain on day 0 through 15 and a second CT and an MRI of the brain on day 16 through 180 after acute stroke onset. RESULTS: There were 200 patients with cerebral infarction and 28 patients with intracerebral hemorrhage. Intracerebral hemorrhage was found in 19% of patients with total anterior circulation syndrome and in no patients with lacunar syndrome (chi 2 test; P < .01 for the difference between the four clinical subgroups). Of the 200 patients with cerebral infarction, 27% had total anterior circulation, 30% partial anterior circulation, 26% lacunar, and 16% posterior circulation syndromes. CT within 2 days revealed a visible lesion in about two thirds of patients with infarctions of total or partial anterior circulation syndrome type, compared with only 22% of patients with lacunar infarction (chi 2 test; P = .02 for the difference between the four subgroups). The mean volume of the symptomatic infarction on CT within 15 days was 95 mL for total anterior circulation, 20 mL for partial anterior circulation, and 2.5 mL for lacunar syndrome (one-factor ANOVA; P = .0001). A cortical involvement of the infarction on CT day 16 through 180 was seen in 81% of patients with total anterior circulation syndrome and 58% of those with partial anterior circulation syndrome, compared with only 8% of patients with lacunar syndrome (chi 2 test; P = .0001). MRI more often than CT showed a cortical involvement of lacunar infarctions and also revealed more silent lesions. CONCLUSIONS: The described clinical subgroups significantly differed in frequencies of intracerebral hemorrhage, cortical involvement, and lesion volume on CT and MRI.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Transtornos Cerebrovasculares/classificação , Transtornos Cerebrovasculares/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Hemorragia Cerebral/complicações , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/patologia , Infarto Cerebral/complicações , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/patologia , Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos Cerebrovasculares/etiologia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
15.
Stroke ; 25(5): 929-34, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8165686

RESUMO

BACKGROUND AND PURPOSE: To assess the prevalence of asymptomatic abnormalities on magnetic resonance imaging of the brain and their possible relation to hypertension, heart disease, and carotid artery disease, we studied 77 randomly selected subjects (mean age, 65.1 years; range, 36 to 95 years) with no history of focal brain lesions. METHODS: The study protocol included magnetic resonance imaging of the brain, transthoracic and transesophageal echocardiography, ultrasonography of the carotid arteries, and electrocardiographic recording. Deep and periventricular white matter hyperintensities on magnetic resonance imaging were assessed both separately and together. RESULTS: On magnetic resonance imaging of the brain 62.3% (95% confidence interval [CI], 51.5% to 73.2%) of the subjects had white matter hyperintensities. These abnormalities increased significantly with age (chi 2 test; P = .0001), from 13.6% (95% CI, 0% to 28.0%) of subjects aged younger than 55 years to 85.2% (95% CI, 71.8% to 98.6%) of subjects aged 75 years or older. Six subjects had deep gray matter hyperintensities localized in the basal ganglia, and one had a cerebellar infarction. Stepwise logistic regression analysis identified age and a history of heart disease (but not echocardiographic findings) to be independently associated with deep and periventricular white matter hyperintensities. Hypertension was only independently associated with periventricular white matter hyperintensities. Of the 68 subjects examined with both transthoracic and transesophageal echocardiography, potential cardioembolic sources were detected in 38.2% (95% CI, 26.7% to 49.8%) of the subjects with transthoracic echocardiography and in 47.1% (95% CI, 35.2% to 58.9%) of those with transthoracic and transesophageal echocardiography combined. In subjects aged 75 years or older, a possible cardiac embolic source was detected in 64.0% on transthoracic echocardiography and in 72.0% on transthoracic and transesophageal echocardiography combined, compared with 5.3% and 15.8%, respectively, in subjects aged younger than 55 years. CONCLUSIONS: White matter hyperintensities and potential cardioembolic sources are frequently present in asymptomatic individuals, stressing the need for age-matched control subjects in studies of patients with stroke or dementia.


Assuntos
Encefalopatias/diagnóstico , Cardiopatias/diagnóstico , Adulto , Idoso , Encefalopatias/diagnóstico por imagem , Encefalopatias/epidemiologia , Estenose das Carótidas/diagnóstico , Estenose das Carótidas/etiologia , Transtornos Cerebrovasculares/diagnóstico , Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos Cerebrovasculares/epidemiologia , Transtornos Cerebrovasculares/etiologia , Ecocardiografia Transesofagiana , Embolia/complicações , Embolia/diagnóstico , Feminino , Cardiopatias/complicações , Cardiopatias/diagnóstico por imagem , Cardiopatias/epidemiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fatores de Risco
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