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1.
Br J Radiol ; 80(956): 668-73, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17681985

RESUMO

This paper aims to demonstrate the capabilities of a speed optimized T(2) weighted single-shot turbo spin echo sequence, using parallel imaging, variable flip angle refocusing and half-Fourier acquisition (FAS-TSE), in comparison with a standard TSE (sTSE) sequence in patients with suspected multiple sclerosis (MS). 33 patients presenting with a clinically isolated syndrome (CIS) suggestive of MS were prospectively examined on a 3.0 T MR system using FAS-TSE and a sTSE sequence. The FAS-TSE (scan time 11 s) and the sTSE (scan time 122 s) were compared regarding lesion detectability, lesion contrast, grey/white matter contrast, overall image quality and artefacts. Scanning parameters affecting image contrast and spatial resolution were kept identical. 208 lesions were detected using the sTSE sequence compared with 183 lesions (88%) using the FAS-TSE. The FAS-TSE was rated inferior regarding lesion contrast. The mean value/range/standard deviation of the lesion/white matter contrast were 0.26/0.06-0.49/0.089, respectively, with the sTSE vs 0.21/0.04-0.40/0.081 with the FAS-TSE. The FAS-TSE was rated inferior regarding overall image quality, but superior regarding motion artefacts. The grey/white matter contrast was qualitatively judged as comparable for both sequences. FAS-TSE provides sufficient T2-SE contrast and diagnostic image quality for whole brain studies in 11 s. It is suited to reduce motion artefacts in restless patients and for fast acquisition of additional scanning planes.


Assuntos
Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico , Medula Espinal/patologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
Eur Radiol ; 17(2): 503-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16604322

RESUMO

The purpose of this study was to compare the in-built body coil of the 3.0-Tesla (T) scanner with a dedicated surface coil of a 1.5 T system regarding knee imaging. We performed an intraindividual prospective clinical trial on 17 patients with knee pain using magnetic resonance imaging (MRI) at 1.5 and 3.0 T systems equipped with identical gradient systems. Proton-density-weighted turbo spin echo sequences with the same spatial resolution and comparable contrast parameters were used. A quantitative measurement of signal to noise ratio (SNR), relative contrast (RC) and contrast to noise ratio (CNR) between muscle and bone marrow was performed, followed by a qualitative assessment of anatomic/pathologic structures and the extent of artefacts. At 3.0 T, 30 lesions (91%) compared to 33 lesions at 1.5 T were detected. The SNR/CNR/RC were moderately reduced at 3.0 T versus 1.5 T (muscle 42 vs 47 and bone 83 vs 112/46 vs 69/0.33 vs 0.43). Motion artefacts from the pulsating popliteal artery were significantly increased at 3.0 T. A visible and measurable signal loss occurred at 3.0 T using the built-in body coil compared with the dedicated 1.5 T knee coil, but nearly all clinically important information could be obtained.


Assuntos
Articulação do Joelho/patologia , Imageamento por Ressonância Magnética , Dor/patologia , Adulto , Artefatos , Cartilagem Articular/patologia , Imagem Ecoplanar , Estudos de Viabilidade , Feminino , Alemanha , Humanos , Processamento de Imagem Assistida por Computador , Ligamentos Articulares/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Prótons
3.
Eur J Radiol ; 61(2): 256-61, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17034975

RESUMO

OBJECTIVES: We evaluated the feasibility of highfield lung-MRI at 3.0T. A comparison with Computed Tomography (CT) and clinical data regarding the assessment of inflammatory activity in patients with diffuse lung disease was performed. MATERIAL AND METHODS: Prospective evaluation of 21 patients (15 males, 6 females, 43-80 y) with diffuse lung diseases who underwent clinical work-up inclusive laboratory tests, lung-function tests and transbronchial biopsy. After routine helical CT (additional 12 HRCT) a lung-MRI (3.0 Intera, Philips Medical Systems, Best, The Netherlands) using a T2-weighted, cardiac and respiratory triggered Fast-Spinecho-Sequence (TE/TR=80/1500-2500 ms, 22 transverse slices, 7/2mm slice-thickness/-gap) was performed. A pneumologist classified the cases into two groups: A=temporary acute interstitial disease or chronic interstitial lung disease with acute episode or superimposed infection/B=burned out interstitial lung disease without activity. Two blinded CT-radiologists graded the cases in active/inactive disease on the basis of nine morphological criteria each. A third radiologist rated the MRI-cases as active/inactive, depending on the signal-intensities of lung tissues. RESULTS: The pneumologist classified 14 patients into group A and 7 patients into group B. Using CT, 6 cases were classified as active, 15 cases as inactive disease. With MRI 12 cases were classified as active and 9 cases as inactive. In the complete group of 21 patients MRI decisions and CT decisions respectively were false positive/false negative/correct in 2/4/15 respectively 0/8/13 cases. Correct diagnoses were obtained in 72% (MRI) respectively 62% (CT). In the subgroup of 12 cases including HRCT, MRI respectively CT were false positive/false negative/correct in 2/1/9 respectively 0/5/7 cases. Correct diagnoses were obtained in 75% (MRI) respectively 58% (CT). CONCLUSION: Highfield MRI of the lung is feasible and performed slightly better compared to CT in the determination of activity in patients with interstitial lung diseases.


Assuntos
Inflamação/fisiopatologia , Doenças Pulmonares Intersticiais/fisiopatologia , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Inflamação/diagnóstico por imagem , Inflamação/patologia , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
4.
Rofo ; 177(6): 818-27, 2005 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-15902631

RESUMO

PURPOSE: To investigate the respective diagnostic accuracies of the different breast imaging modalities, i. e., mammography (Mx), high-frequency breast ultrasound (US), and dynamic contrast-enhanced breast (MRI) regarding the early diagnosis of familial (hereditary) breast cancer. MATERIALS AND METHODS: A prospective, non-randomized controlled clinical multi-center trial is performed at 4 academic tertiary care centers in Germany (Ulm, Munchen/Grosshadern, Munster and Bonn) for a total period of 4 years, sponsored by the German Cancer Aid. The protocol consists of semiannual clinical visits and breast ultrasound, and annual bilateral two-view Mx, US and MRI. Imaging studies were first analyzed independently, then Mx was read in conjunction with US, followed by Mx combined with MRI, and finally, all three imaging modalities were read in synopsis. We present the concept and first results of this trial. RESULTS: So far, 748 screening rounds are available for analysis in 613 women. A total of 12 breast cancers have been identified, with 11/12 cases in the pTis or pT1/N0 stage. The mean size of detected invasive cancers was 7 mm. A total of 19 benign lesions were biopsied due to false-positive imaging diagnoses. The breast cancer detection rates were: Mx: 5/12 (42 %), US 3/12 (25 %), MRI 10/12 (83 %), and the positive predictive values: Mx 5/17 (29 %), US 3/15 (30 %), and MRI 10/23 (43 %). CONCLUSION: The preliminary data suggest that early diagnosis of familial breast cancer is feasible by intensified surveillance, in particular with the addition of MRI.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética , Mamografia , Ultrassonografia Mamária , Adulto , Biópsia , Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/prevenção & controle , Reações Falso-Positivas , Feminino , Seguimentos , Predisposição Genética para Doença , Alemanha , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo
5.
Eur Radiol ; 15(2): 324-8, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15565313

RESUMO

The purpose of this study was to evaluate the feasibility of high-field magnetic resonance imaging (MRI) of the lung using a T2-weighted fast-spin echo (TSE) sequence. Comparison was made with helical computed tomography CT findings in patients with diffuse pulmonary diseases. Prospective segment-wise analysis of high-field MR imaging findings in 15 patients with diffuse pulmonary diseases was made using helical CT and HRCT as the standard of reference. The MR studies were performed on a 3.0-T whole body system (Intera 3T, Philips Medical Systems) using a T2w TSE sequence with respiratory and cardiac gating (TE 80 ms TR 1,500-2,500 ms; turbo factor 17; 22 slices with 7/2-mm slice thickness and gap; 256x192 matrix). MR artifacts were graded on a three-point scale (low, moderate, high). Lung MR studies were prospectively analyzed segment-by-segment and diagnosed as healthy or pathological; results were compared with helical CT findings. In all 15 patients, MR imaging of the lung was successful. All 15 MR studies were compromised by artifacts; however, the severity of these artifacts was classified as low or moderate in 8/15, respectively, 7/15 cases. A total of 143/285 lung segments showed diffuse lung disease in helical CT. With MRI, 133 of these 143 segments (93%) were judged to be diseased. The ten segments that received false negative MR diagnoses displayed non-acute pulmonary lesions with inherently low proton density (scars, granulomas). MRI at 3.0 T can detect diffuse pulmonary disease with a high sensitivity. Based on this experience, further pulmonary studies with high-field systems appear justified and promising.


Assuntos
Pneumopatias/diagnóstico , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Pneumopatias/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
6.
Radiology ; 220(1): 31-9, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11425969

RESUMO

PURPOSE: To report our experience with magnetic resonance (MR) imaging-guided large-core breast biopsy of lesions visible at breast MR imaging only. MATERIALS AND METHODS: Stereotactic large-core (14-gauge) needle biopsy of 78 lesions visible at MR imaging only was performed with MR imaging guidance in 59 patients. Results were validated with excisional biopsy or mastectomy in 42 lesions and with radiologic-pathologic correlation and/or follow-up MR imaging for at least 2 years in another 17 lesions. The accuracy of MR imaging--guided core biopsy was determined for those 59 lesions with established validation. The effect on patient treatment was evaluated by comparing the prebiopsy treatment plan with the ultimate treatment. RESULTS: Histologic diagnosis from core biopsy was possible in 77 (99%) of 78 lesions. In the 59 lesions with established validation, the diagnostic accuracy of MR imaging--guided core biopsy was 98% (58 of 59). Successful MR imaging--guided core biopsy findings changed treatment in 70% (54 of 77) of lesions. Difficulties were due to the unsatisfactory performance of earlier types of MR imaging--compatible biopsy guns and decreasing target visibility during intervention. CONCLUSION: MR imaging--guided large-core stereotactic breast biopsy is sufficiently accurate for obtaining histologic proof of lesions visible only at MR imaging. It can change patient treatment by reducing unnecessary surgical biopsy and can enable one-step surgery for breast cancers.


Assuntos
Neoplasias da Mama/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Biópsia por Agulha/métodos , Estudos de Coortes , Feminino , Humanos , Mamografia/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença
10.
Aktuelle Radiol ; 8(3): 145-7, 1998 May.
Artigo em Alemão | MEDLINE | ID: mdl-9645254

RESUMO

A young female patient was admitted for clarification of a space-occupying ovarian situation. Histological analysis gave the finding of a highly malignant NHL of the Burkitt type. In the further course of the disease bicytopenia developed. Bone mark analysis revealed a B-AII. FAB L3 which can be considered as the leukemic equivalent of the Burkitt lymphoma. In spite of chemotherapy the patient died as a consequence of a sepsis.


Assuntos
Linfoma de Burkitt/diagnóstico por imagem , Neoplasias Ovarianas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Linfoma de Burkitt/patologia , Feminino , Seguimentos , Humanos , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Ovário/diagnóstico por imagem , Ovário/patologia
11.
Aktuelle Radiol ; 8(2): 104-6, 1998 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-9592587

RESUMO

Cystic tumours of the spleen are generally rare and a parasitic origin is relatively improbable. Our case report, however, shows that in case of a splenic cyst, differential diagnosis must always consider the possibility of echinococcosis. We report on a patient suffering from a cystic lesion of the spleen where radiology yielded the final pointer to diagnosing an echinococcosis of the spleen.


Assuntos
Equinococose/diagnóstico por imagem , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Baço/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Ultrassonografia
15.
Exp Hematol ; 24(2): 392-7, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8641371

RESUMO

Reportedly, recombinant human erythropoietin (rhEpo) can induce constriction of isolated resistance vessels. We have studied whether rhEpo affects cytosolic calcium concentration, [Ca2+]i, and contraction of cultured smooth-muscle cells grown from rat renal corpuscles and aortae. rhEpo at high dose (> or = 20 U/mL) induced a transient increase in [Ca2+]i as detected by fura-2 fluorescence analysis. The number of cells responding with an increase in [Ca2+]i was dose-dependent. No significant changes of [Ca2+]i occurred when lower doses of rhEpo (< 20 U/mL) were applied. The effect of Epo on contraction was studied by phase-contrast microscopy. The number of cells responding with contraction was dose-dependent, too (76% mesangial cells contracting at 200 U rhEpo per mL). The receptor mechanism of this unusual action of Epo still needs to be clarified.


Assuntos
Aorta Torácica/citologia , Cálcio/metabolismo , Eritropoetina/farmacologia , Mesângio Glomerular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Animais , Sequência de Bases , Transporte Biológico/efeitos dos fármacos , Células Cultivadas , Citosol/metabolismo , Relação Dose-Resposta a Droga , Expressão Gênica , Humanos , Masculino , Dados de Sequência Molecular , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Especificidade de Órgãos , Ratos , Ratos Sprague-Dawley , Receptores da Eritropoetina/análise , Receptores da Eritropoetina/genética , Proteínas Recombinantes/farmacologia , Vasoconstrição/efeitos dos fármacos
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