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1.
Oral Dis ; 23(8): 1127-1133, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28650084

RESUMEN

OBJECTIVE: This study aimed to identify and quantify polyomaviruses (BKPyV and JCPyV) in the saliva, mouthwash, blood and urine of liver pretransplant patients. MATERIALS AND METHODS: A case-control study was performed using a convenience sample of 21 end-stage liver disease patients (EG = experimental group) and 20 normoreactive controls (CG = control group). In total, 162 samples were collected. Detection and quantification of polyomaviruses were performed using real-time PCR method. RESULTS: In the EG, 21 samples (25%) were positive for BKPyV and 10 (11.90%) for JCPyV, while in the CG, 27 samples (34.61%) were positive for BKPyV and six (7.69%) for JCPyV. With regard to the number of samples positive for BKPyV and JCPyV, there was no statistically significant difference between EG and CG (p = .52 and p = .25). In the EG, we observed a panorama similar to that of the CG regarding the presence of polyomaviruses in mouthwash, blood and urine. The greatest difference between the samples was that regarding the identification of BKPyV in saliva. CONCLUSION: Cirrhotic patients on the liver transplant waiting list did not show higher prevalence of BKPyV and JCPyV compared to normoreactive controls.


Asunto(s)
Virus BK/aislamiento & purificación , Virus JC/aislamiento & purificación , Infecciones por Polyomavirus/virología , Saliva/virología , Infecciones Tumorales por Virus/virología , Adulto , Sangre/virología , Estudios de Casos y Controles , Enfermedad Hepática en Estado Terminal/cirugía , Femenino , Humanos , Trasplante de Hígado , Masculino , Persona de Mediana Edad , Periodo Preoperatorio , Orina/virología , Carga Viral
2.
Plant Physiol ; 115(2): 409-418, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12223816

RESUMEN

Tomato (Lycopersicon esculentum Mill.) polyphenol oxidases (PPOs) are encoded by a seven-member gene family that exhibits complex patterns of differential expression during growth and differentiation. Antisense down-regulation of constitutive and induced PPO expression results in hypersusceptibility to pathogens, suggesting a critical role for PPO-mediated phenolic oxidation in plant defense. However, the nature and extent of PPO induction and its contribution to resistance are unclear. In this study we examined the inducibility of the tomato PPO gene family. In mature plants PPO transcript levels systemically increased in young leaves (nodes 1-3) when mature leaflets (node 5) were injured. Transcripts hybridizing to PPO E/F-specific probes were the predominant wound-induced PPO mRNAs in young leaves. Analysis of PPO promoter: GUS fusion constructs shows that mechanical wounding and infection by fungal and bacterial pathogens induced transcription of PPO F. Different injuries, salicylic acid, ethylene, and jasmonates elicited distinct, cell-specific and developmental stage-specific patterns of PPO F expression. Whereas jasmonates and mechanical wounding significantly induced PPO F only in young leaves (nodes 1-3), and ethylene induced PPO F only in older leaves (node 7), salicylic acid induced PPO F in stems and foliage at all developmental stages. These results demonstrate that cis-element(s) sufficient for PPO F inducibility reside in the 5[prime] flanking region, and these elements are responsive to a broad range of signals.

3.
Plant Physiol ; 113(3): 707-718, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12223637

RESUMEN

Polyphenol oxidases (PPOs) are encoded by a highly conserved, seven-member gene family clustered within a 165-kb locus on chromosome 8 of tomato (Lycopersicon esculentum). Using gene-specific probes capable of differentiating between PPO A/C, PPO B, PPO D, and PPO E/F, we examined the spatial and temporal expression of this gene family during vegetative and reproductive development. RNA blots and in situ hybridization using these probes showed that although PPO expression is primarily confined to early stages of development, the steady-state mRNA levels of these genes are subject to complex patterns of spatial and temporal regulation in vegetative and reproductive organs. Young tomato leaves and flowers possess the most abundant PPO transcripts. PPO B is the most abundant in young leaves, whereas in the inflorescence PPO B and E/F transcripts are dominant. Differential expression of PPOs is also observed in various trichome types. PPO A/C are specifically expressed in type I and type IV trichomes. In contrast, PPO D is only expressed in type VI trichomes. Type I, IV, and VI trichomes possess PPO E/F transcripts. Immunolocalization verified the translational activity of PPOs identified by in situ hybridization and suggested cell-type-specific, developmentally programmed PPO turnover. In addition, immunolocalization demonstrated the accumulation of PPO in specific idioblast cells of stems, leaves, and fruits.

4.
Plant Physiol ; 115(4): 1581-1587, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12223881

RESUMEN

UDP-glucose (UDP-Glc):fatty acid glucosyltransferases catalyze the UDP-Glc-dependent activation of fatty acids as 1-O-acyl-[beta]-glucoses. 1-O-Acyl-[beta]-glucoses act as acyl donors in the biosynthesis of 2,3,4-tri-O-acylglucoses secreted by wild tomato (Lycopersicon pennellii) glandular trichomes. The acyl composition of L. pennellii 2,3,4-tri-O-acylglucoses is dominated by branched short-chain acids (4:0 and 5:0; approximately 65%) and straight and branched medium-chain-length fatty acids (10:0 and 12:0; approximately 35%). Two operationally soluble UDP-Glc:fatty acid glucosyltransferases (I and II) were separated and partially purified from L. pennellii (LA1376) leaves by polyethylene glycol precipitation followed by DEAE-Sepharose and Cibacron Blue 3GA-agarose chromatography. Whereas both transferases possessed similar affinity for UDP-Glc, glucosyltransferase I showed higher specificity toward short-chain fatty acids (4:0) and glucosyltransferase II showed higher specificity toward medium-chain fatty acids (8:0 and 12:0). The overlapping specificity of UDP-Glc:fatty acid glucosyltransferases for 4:0 to 12:0 fatty acid chain lengths suggests that the mechanism of 6:0 to 9:0 exclusion from acyl substituents of 2,3,4-tri-O-acylglucoses is unlikely to be controlled at the level of fatty acid activation. UDP-Glc:fatty acid glucosyltransferases are also present in cultivated tomato (Lycopersicon esculentum), and activities toward 4:0, 8:0, and 12:0 fatty acids do not appear to be primarily epidermal when assayed in interspecific periclinal chimeras.

5.
Invest Radiol ; 35(2): 97-104, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10674453

RESUMEN

RATIONALE AND OBJECTIVES: To evaluate neointimal hyperplasia, plaque distribution, and morphologic features of peripheral arterial stent-grafts with intravascular ultrasound (IVUS). METHODS: Twenty-three patients with stenoses or occlusions of the pelvic or femoral arteries were treated with 31 stent-grafts. Angiography and IVUS of the stented artery were performed 13.9 +/- 9.7 months after stent implantation. Maximum in-stent restenosis was measured by IVUS. Plaque composition and lesion topography were also assessed. RESULTS: The maximum in-stent restenosis was 53.2 +/- 26.5% for the femoral and 14.2 +/- 10.1 for pelvic arterial stent-grafts. Predilection sites of maximum neointimal tissue accumulation were the edges of the femoral stent-grafts. Only small amounts of neointimal hyperplasia were found in the stent-graft edges. No predilection site for maximum in-stent restenosis was found for the pelvic arterial stent-grafts. CONCLUSIONS: Predilection sites of maximum in-stent restenosis were the edges of femoral stent-grafts in contrast to pelvic stent-grafts. Femoral stent-grafts showed significantly higher graded stenoses with IVUS than iliac stent-grafts. The authors' findings at IVUS did not change the treatment plan in these patients treated with stent-grafts.


Asunto(s)
Arteriopatías Oclusivas/diagnóstico por imagen , Arteriopatías Oclusivas/cirugía , Prótesis Vascular , Oclusión de Injerto Vascular/diagnóstico por imagen , Stents , Ultrasonografía Intervencional , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia
6.
Invest Radiol ; 32(2): 100-4, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9039582

RESUMEN

RATIONALE AND OBJECTIVES: The authors describe the clinical status of liver tissue with only a single numerical quantity (total entropy) derived from spectroscopic data of 31P-magnetic resonance (MR) spectra. METHODS: Twenty-four patients with liver metastases and 20 volunteers were investigated with image-guided volume selective 31P-MR spectroscopy on a 1.5-T whole body scanner. From each in vivo 31P-MR spectrum, the ratios of phosphomonoester (PME)/beta-adenosine triphosphate (ATP), inorganic phosphate (Pi)/beta-ATP and phosphodiester (PDE)/ beta-ATP and the total entropy (H*) were calculated. Mean values and standard deviations were determined and significance of the differences were tested with Student's t test. RESULTS: For patients, the H* = 4.7 +/- 4.3, PME/beta-ATP 0.72 +/- 0.28, Pi/beta-ATP = 1.00 +/- 0.39, PDE/beta-ATP = 1.68 +/- 0.59. For the volunteers, H* = 7.6 +/- 2.5, PME/beta-ATP = 0.39 +/- 0.15, Pi/beta-ATP = 0.90 +/- 0.19, PDE/beta-ATP = 1.25 +/- 0.28. The total entropy of patients' spectra showed significantly lower values compared with those of volunteers. PME/beta-ATP and PDE/beta-ATP of the patients increased and differed significantly from volunteer data. CONCLUSIONS: It was demonstrated that the results of in vivo 31P-MR spectroscopy may be described with a single criterion by means of the total entropy.


Asunto(s)
Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundario , Hígado/metabolismo , Imagen por Resonancia Magnética/métodos , Fósforo/metabolismo , Adenosina Trifosfato/metabolismo , Adulto , Biopsia , Entropía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hidrolasas Diéster Fosfóricas/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Isótopos de Fósforo , Tomografía Computarizada por Rayos X
7.
AJNR Am J Neuroradiol ; 17(1): 89-94, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8770255

RESUMEN

PURPOSE: To determine whether spiral CT angiography allows accurate, quantitative evaluation of anatomic abnormalities, including detection of additional lesions, delineation of plaque morphology, and estimation of degree of internal carotid artery stenosis. METHODS: Spiral CT angiography with a maximum intensity projection technique was compared with selective digital subtraction angiography (DSA) in 92 carotid arteries. The category of stenosis was determined according to the North American Symptomatic Carotid Endarterectomy Trial: mild (0% to 29%), moderate (30% to 69%), severe (70% to 99%), and occlusion (100%). RESULTS: In 78 (85%) of the 92 cases, spiral CT angiography and selective DSA demonstrated the same degree of stenosis. All occlusions (n = 19) were diagnosed correctly with spiral CT angiography. Spiral CT angiography agreed with selective DSA in the classification of stenosis in 59% of the group with mild stenosis, in 82% of the group with moderate stenosis, and in 90% of the group with severe stenosis. In the groups with mild (n = 13), moderate (n = 9), and severe (n = 27) stenosis, correlation of spiral CT angiography with selective DSA was significant. Calcified plaques were readily diagnosed with the use of spiral CT angiography but delineation of ulcers was poor. Tandem lesions were not visible owing to the limited coverage. CONCLUSION: Spiral CT angiography is useful for the detection of proximal internal carotid stenoses that are greater than 30%. Depiction of mild stenoses appears to be limited. CT is superior for the detection of calcified plaques but it is not useful for the detection of ulcers.


Asunto(s)
Angiografía de Substracción Digital , Arteria Carótida Interna/diagnóstico por imagen , Estenosis Carotídea/diagnóstico por imagen , Angiografía Cerebral , Trastornos Cerebrovasculares/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Estenosis Carotídea/clasificación , Trastornos Cerebrovasculares/clasificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos
8.
Neurol Res ; 20(8): 705-8, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9864734

RESUMEN

The utility of magnetic resonance angiography is sometimes limited in the diagnostic workup of cerebral aneurysms with low flow and/or partial thrombosis when weighed against digital subtraction angiography. We present the case of a rare superior cerebellar artery giant, partially thrombosed aneurysm in which additional i.v. contrast-enhanced MRA sequences were comparable to digital subtraction angiography. It demonstrated not only the exact spatial resolution and correct anatomical relation but also the hemodynamics which were confirmed by intraoperative Doppler ultrasound. This report supports the feasibility and utility of i.v. contrast-enhanced MRA for posterior fossa giant cerebral aneurysm management.


Asunto(s)
Angiografía Cerebral/métodos , Fosa Craneal Posterior , Aneurisma Intracraneal/diagnóstico , Angiografía por Resonancia Magnética/métodos , Cerebelo/irrigación sanguínea , Circulación Cerebrovascular , Humanos , Masculino , Persona de Mediana Edad , Puente/irrigación sanguínea
9.
Br J Radiol ; 70(833): 440-5, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9227223

RESUMEN

Arterial gas embolism due to barotrauma of the lungs is a severe complication in compressed air diving. Precipitating factors are often missed on plain chest radiology. This study was conducted to detect occult lung disease predisposing to the development of pulmonary barotrauma in conditions associated with a change in ambient pressure. During the past 4 years, 11 patients who have suffered pulmonary barotrauma with or without subsequent development of cerebral or spinal arterial gas embolism underwent computed tomography of the chest several days post-injury. Examinations were conducted either using the conventional technique (n = 7) or, more recently, in the spiral mode (n = 4). Chest radiographs were available in all cases. In five patients CT revealed subpleural emphysematous blebs or cysts that were not detected by conventional radiography. Follow-up studies performed in two of these cases several months post-injury showed that the cystic lesions did not resolve. We assume that the lung cysts or blebs are preexisting conditions which caused pulmonary barotrauma. Computed tomography of the chest, preferably in the spiral mode, is recommended in any case of suspected pulmonary barotrauma in order to evaluate the possibility of pre-existing pathology and to predict future fitness to dive.


Asunto(s)
Barotrauma/etiología , Quistes/diagnóstico por imagen , Buceo/efectos adversos , Embolia Aérea/etiología , Enfermedades Pulmonares/diagnóstico por imagen , Adulto , Barotrauma/diagnóstico por imagen , Quistes/complicaciones , Embolia Aérea/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Enfermedades Pulmonares/complicaciones , Masculino , Tomografía Computarizada por Rayos X
10.
Rofo ; 169(1): 22-6, 1998 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-9711278

RESUMEN

PURPOSE: To determine the usefulness of contrast-enhanced MR angiography for the diagnosis of Leriche's syndrome. MATERIAL AND METHODS: Leriche's syndrome was seen in 7 patients via DSA. In addition, contrast-enhanced MR angiography was performed (TR 7.8 ms/TE 2.1 ms, flip angle 30 degrees, slab thickness 116 mm, slice thickness 1.82 mm, 64 partitions, FOV 500 x 438 mm, matrix 224 x 512). RESULTS: Diagnosis of Leriche's syndrome was possible by contrast-enhanced MR angiography in each case. Visualisation of the femoral arteries was not possible in two patients by intraarterial DSA, in three other patients there was an insufficient contrast in the femoral arteries with DSA. Contrast-enhanced MR angiography revealed good visualisation of the femoral arteries in these patients. In addition, contrast-enhanced MR angiography allowed complete visualisation of the patent lower limb arteries. In intraarterial DSA visualisation of the lower limb arteries was achieved reached in only one patient, but was incomplete. CONCLUSION: Contrast-enhanced MR angiography yielded the correct diagnosis of Leriche's syndrome in all 7 patients. Contrast-enhanced MR angiography was superior to DSA in the assessment of the distal run-off vessels in five of seven patients.


Asunto(s)
Medios de Contraste , Gadolinio DTPA , Síndrome de Leriche/diagnóstico , Angiografía por Resonancia Magnética/métodos , Adulto , Anciano , Angiografía de Substracción Digital , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad
11.
Rofo ; 172(12): 985-91, 2000 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-11199442

RESUMEN

PURPOSE: The value of DSA for the measurement of aortic and peripheral arterial aneurysm dimensions before endovascular treatment is limited by projection effects. It was evaluated if additional gadolinium-enhanced three-dimensional MR angiography (3D-CEMRA) could compensate for the disadvantages of DSA. MATERIALS AND METHODS: 21 patients with 35 aneurysms in the abdominal aorta (14), iliac (9) and femoropopliteal vessels (12) were assessed with DSA (7 with calibrated catheter, 14 with yardstick) and 3D-CEMRA (TR/TE 7.8/2.1 ms, flip-angle 40 degrees, Matrix 512 x 224, FOV 500 mm, eff. slice 1.8 mm). We measured and compared aneurysm dimensions on both modalities. 3D-CEMRA was regarded as the reference method to evaluate the dimension of DSA-projection effects. RESULTS: Diameter and length of aneurysms were underestimated on DSA with the yardstick as reference. The deviation ranged from 15% (+/- 5%) in the aorta to 21% (+/- 10%) in the iliac vessels. Only with calibrated catheters as reference (7/21 DSA), were the distances on DSA correlated well with MRA. In 2/35 aneurysms 3D-CEMRA detected thrombosis with difference between length of inner lumen dilatation on DSA and whole aneurysm length. 2/5 accessory renal arteries found on DSA were not detected on 3D-CEMRA. CONCLUSIONS: 3D-CEMRA is a valuable adjunct to DSA for pre-interventional diagnostics of aortic and peripheral arterial aneurysms. It provides exact evaluation of aneurysm dimensions and information about partial thrombosis.


Asunto(s)
Aneurisma/diagnóstico , Aneurisma de la Aorta Abdominal/diagnóstico , Aneurisma Ilíaco/diagnóstico , Angiografía por Resonancia Magnética/métodos , Enfermedades Vasculares Periféricas/diagnóstico , Aneurisma/diagnóstico por imagen , Aneurisma/terapia , Angiografía , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/terapia , Calibración , Medios de Contraste , Arteria Femoral , Humanos , Aneurisma Ilíaco/diagnóstico por imagen , Aneurisma Ilíaco/terapia , Enfermedades Vasculares Periféricas/diagnóstico por imagen , Enfermedades Vasculares Periféricas/terapia , Arteria Poplítea , Arteria Renal , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
Rofo ; 167(5): 474-8, 1997 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-9440892

RESUMEN

PURPOSE: The purpose of this prospective study was to evaluate the clinical value of 3D-MR-myelography (3D-MRM) in comparison to myelography and intra-operative findings. MATERIAL AND METHODS: 25 patients with suspected lumbar spinal canal stenosis were studied via myelography and 3D-MRM (volume-data set, 3D-FISP sequence, TR 73 ms, TE 21 ms, flip angle 7 degrees, sagittal slices) besides the routinely acquired sagittal and axial T1- and T2-weighted images. Diagnoses were made by two radiologists and one neurosurgeon without knowing the clinical history and symptoms, in two separate sessions. Results were compared to intraoperative findings. RESULTS: 3D-MRM has the same diagnostic sensitivity (25/25 = 100%) as conventional X-ray myelography (25/25 = 100%) compared to intraoperative findings, but is not invasive and shows more diagnostic details than myelography. Especially in cases of high-grade spinal canal stenosis there is often a lack of intrathecal contrast medium distally of the stenosis. CONCLUSION: 3D-MRM is as good as conventional myelography in predicting intraoperative findings in patients with lumbar spinal canal stenosis. This new method is non-invasive and can be performed routinely on an outpatient basis.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Mielografía/métodos , Estenosis Espinal/diagnóstico , Adulto , Estudios de Evaluación como Asunto , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Imagen por Resonancia Magnética/instrumentación , Masculino , Estudios Prospectivos , Estenosis Espinal/diagnóstico por imagen
13.
Rofo ; 165(5): 466-9, 1996 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-8998319

RESUMEN

PURPOSE: To determine the ability of MRI to diagnose morphological and functional changes in patients after Ross procedure. MATERIAL AND METHODS: During one year, 5 patients after Ross procedure were studied by MRI. T1-weighted spin-echo sequences in different orientations as well as cine sequences and a VENC sequence were used. RESULTS: In all patients the morphology including the postoperative changes could be visualised by MRI. The cine sequences provided functional information on valvular and ventricular function. VENC-MR yielded an exact quantification of the regurgitant fraction. CONCLUSION: MRI is capable of providing all important diagnostic information in patients after Ross procedure such as valvular and ventricular function and valvular and outflow tract morphology in a single examination.


Asunto(s)
Válvula Aórtica/patología , Válvula Aórtica/cirugía , Imagen por Resonancia Magnética , Complicaciones Posoperatorias/diagnóstico , Adolescente , Adulto , Femenino , Enfermedades de las Válvulas Cardíacas/diagnóstico , Enfermedades de las Válvulas Cardíacas/cirugía , Humanos , Imagen por Resonancia Magnética/instrumentación , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Cinemagnética/métodos , Masculino , Válvula Pulmonar/trasplante , Trasplante Autólogo
14.
Rofo ; 168(2): 191-4, 1998 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-9519054

RESUMEN

PURPOSE: To compare the efficacy of vacuum pump controlled aspiration thrombectomy (VPCAT) with the Amplatz thrombectomy device (ATD) for treatment of thrombotic occlusions. MATERIALS AND METHODS: In a flow-model a superficial femoral artery is simulated. VPCAT provides the connection either of an aspiration catheter (AC, 8 F) or a multipurpose catheter (MPC, 8 F) with a vacuum pump (-110 mbar underpressure). 7 day old porcine blood (n = 30; 7.4 g +/- 0.1g) was treated with AC and MPC (VPCAT technique) and with the ATD. RESULTS: Complete thrombectomy was achieved with all techniques. Thrombectomy time was short for ATD (8.8 +/- 0.94 s; p < 0.01). MPC caused the least overall weight of emboli related to thrombus weight (5.14 0/100; p < 0.01). ATD caused the least embolisms at 1000 microns (3.27 mg; p < 0.05), and the most embolisms at 100 microns and at 10 microns (26.5 mg and 26.9 mg; p < 0.01). The aspirated volume of the MPC (33 +/- 17 ml) was half the volume of the AC (65 +/- 25 ml). CONCLUSIONS: In-vitro, VPCAT proves to be an alternative procedure to ATD. The use of a wide lumen multipurpose catheter is advantageous. In vitro, embolism rates of all methods are sufficiently low.


Asunto(s)
Trombectomía/instrumentación , Análisis de Varianza , Animales , Cateterismo , Estudios de Evaluación como Asunto , Arteria Femoral , Filtración/instrumentación , Técnicas In Vitro , Succión/instrumentación , Porcinos , Trombectomía/métodos , Trombectomía/estadística & datos numéricos , Trombosis/terapia , Vacio
15.
Rofo ; 165(6): 544-50, 1996 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-9026096

RESUMEN

PURPOSE: The aim of the study was to assess the value of MR angiography (MRA) in sagittal technique compared to DSA in the evaluation of carotid artery stenosis. METHODS: 80 carotid arteries in 40 symptomatic patients were prospectively studied with DSA and MRA. MRA was carried out by means of 3 D time-of-flight technique with a FISP sequence (TE6 ms/TR80 ms, flip angle 25 degrees, FOV 240 x 210 mm, matrix 157 x 256 mm, in-plane resolution 1.34 x 0.94 mm, partition thickness 1.32 mm, slab thickness 45 mm, acquisition time 7 min) using a new head-neck coll. Data acquisition was performed in sagittal orientation with the "double-slab" technique. Imaging quality of the extracranial carotid arteries and correctness of quantification of stenosis was performed. RESULTS: Imaging quality was good at the origin of the carotid arteries in 65%, at the bifurcation region in 98% and near the skull base in 81%. The agreement of DSA and MRA was 96% of the normal arteries (24/25), 90% of the severe stenoses (28/31) and 100% of the occluded arteries (9/9). CONCLUSION: MRA in sagittal "double-slab" technique is a noninvasive technique allowing to detect normal arteries and candidates for surgery with a high degree of certainty.


Asunto(s)
Estenosis Carotídea/diagnóstico , Angiografía por Resonancia Magnética/métodos , Adulto , Anciano , Angiografía de Substracción Digital , Estenosis Carotídea/diagnóstico por imagen , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
Rofo ; 164(3): 201-5, 1996 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-8672774

RESUMEN

PURPOSE: To determine 3-D time of flight MR angiography for evaluation of fibromuscular dysplasia in cervical vessels. MATERIAL AND METHODS: In 386 selective angiograms of cervical vessels fibromuscular dysplasia was revealed in 4 female patients in the age of 30-54 years. FMD was located in the carotid artery (n = 5) and in the vertebral artery (n = 2) with a total of 8 lesions. RESULTS: 6/8 of the lesions of the seven cervical vessels were located typically in the mid cervical portion of the vessels and 2/6 lesions were located in the atlas loop of the vertebral artery. 4 lesions showed moderate stenosis and 4 vessels showed only mild stenosis. These patterns which demonstrated the typical morphology of fibromuscular dysplasia with alternating irregular zones of widening and narrowing were evaluated well with MR angiography, the others were missed. CONCLUSION: MR angiography is suitable for detection of fibromuscular dysplasia when the characteristic pattern is combined with moderate stenosis of the vessel. Conventional angiography remains the standard of reference.


Asunto(s)
Arteria Carótida Interna/patología , Displasia Fibromuscular/diagnóstico , Angiografía por Resonancia Magnética , Arteria Vertebral/patología , Adulto , Angiografía de Substracción Digital , Ceguera/diagnóstico , Ceguera/etiología , Arteria Carótida Interna/diagnóstico por imagen , Femenino , Displasia Fibromuscular/complicaciones , Humanos , Ataque Isquémico Transitorio/diagnóstico , Ataque Isquémico Transitorio/etiología , Angiografía por Resonancia Magnética/instrumentación , Angiografía por Resonancia Magnética/métodos , Persona de Mediana Edad , Arteria Vertebral/diagnóstico por imagen
17.
Rofo ; 171(2): 143-8, 1999 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-10506889

RESUMEN

PURPOSE: To investigate frequency of acetabular labral lesions in elderly hip joints, and to determine sensitivity and specificity of MR arthrography (MRa) for the detection of these abnormalities. MATERIALS AND METHODS: Twenty cadaveric hip joints were examined by MRa. For MRa, 15 ml of a solution of iodinated contrast solution (Solutrast 300) and Gd-DTPA (100:1) were injected under fluoroscopic guidance. MR imaging was performed on a 1.5 T MR scanner (Vision, Siemens; FOV 16 cm, matrix 256 x 256, fat-suppressed 3D-FLASH). Multiplanar image reconstructions were done perpendicular to the acetabulum in the oblique-coronal, oblique-axial, and radial planes. The labral specimens were examined macroscopically. RESULTS: In 12/20 hips (60%), a labral lesion was found on pathologic examination. In 7 specimens, the labrum was partially or completely detached in the weight-bearing superior region. One flap-like variant of the labrum was seen; in 4 hip joints, the labrum was degenerated (one cystic degeneration). Pathologic findings were confirmed by MRa in 8/12 specimens (sensitivity 67%). All degenerated labra were correctly diagnosed on MRa. Three small labral detachments and the flap-like variant were misinterpreted as being normal. There were no false positive findings (specificity 100%). The accuracy was 80%. Labral lesions were seen in 6/8 and in 6/12 of hips with and without osteoarthritis, respectively. CONCLUSION: MRa is well suited to delineate the acetabular labrum and to diagnose labral abnormalities. Detection of small labral detachments and anatomic variants is difficult and requires some experience. Labral lesions are correlated to osteoarthritis of the hip, but may be frequently seen in the elderly without underlying osteoarthritis.


Asunto(s)
Acetábulo/patología , Articulación de la Cadera/patología , Imagen por Resonancia Magnética , Acetábulo/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Cadáver , Medios de Contraste , Femenino , Gadolinio DTPA , Articulación de la Cadera/diagnóstico por imagen , Humanos , Yopamidol , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Radiografía , Sensibilidad y Especificidad
18.
Rofo ; 168(6): 604-9, 1998 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-9687953

RESUMEN

PURPOSE: To evaluate effectiveness, success and patency rates after endovascular treatment with mid-size Palmaz stents in high-grade stenoses or short-distance occlusions of femoral arteries. MATERIALS AND METHODS: 27 patients with 10 occlusions (average length 3.2 +/- 1.4 cm) and 17 severe stenoses of the superficial femoral artery were treated with 33 mid-size Palmaz stents. The follow-up included Doppler ultrasound at one, three, 6 and 12 months and an angiography at 6 months. Mean follow-up was 6.5 months. RESULTS: Technical success was 100%. The ankle-brachial index improved from 0.57 +/- 0.28 pretreatment to 0.87 +/- 0.13 within 24 hours. Acute stent thrombosis occurred in two patients (< 3 weeks). Angiography at 6 months revealed restenosis rates of 7.4% (> 50%, n = 2). Life-table analysis according to Kaplan-Meier revealed 6-month primary and secondary patency rates of 84% and 91%. CONCLUSION: With regard to our limited data, the implantation of mid-size Palmaz stents in femoral arteries seems promising in treatment of short-distance occlusions and stenoses of the femoral artery.


Asunto(s)
Angioplastia de Balón , Arteriopatías Oclusivas/cirugía , Arteria Femoral , Pierna/irrigación sanguínea , Arteria Poplítea , Stents , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital , Arteriopatías Oclusivas/diagnóstico por imagen , Interpretación Estadística de Datos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Factores de Tiempo
19.
Rofo ; 168(4): 330-6, 1998 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-9589094

RESUMEN

PURPOSE: A comparison of ultra rapid T2-weighted HASTE and HASTE-STIR sequences during suspended respiration for the detection of focal lesions of the liver. MATERIAL AND METHODS: Twenty-one patients (59 +/- 12 years) with a total of 33 focal lesions (7 < or = 1 cm, 19 < or = 3 cm; 17 cystic liquid and 16 solid lesions) were examined with a 1.5 T MR apparatus. Sequences: T2 weighted HASTE (TEeff = 64 ms, 90 ms), HASTE-STIR (TEeff = 64 ms, 81 ms) TSE (TE = 132 ms) and T1-weighted FLASH 2D. RESULTS: The T2-weighted TSE and both HASTE sequences showed all the lesions. Two out of the 33 lesions were not demonstrated by the other sequences. Best image quality without movement artefacts and the best resolution of the lesions in the T2-weighted sequences, with the most favourable contrast/noise ratio (36.6 +/- 33.1) and signal/noise ratio (20.8 +/- 10.5) resulted from the HASTE 90, followed by the HASTE 64 sequence (27.5 +/- 24.2; 24.6 +/- 9.1). Both these techniques were superior to the TSE sequence (23.9 +/- 29.4; 13.9 +/- 7.4), which resulted in movement artifacts. With the HASTE-STIR sequences it was possible to show 31 and 32 of the 33 lesions respectively, with very good resolution but poor signal/noise ratio. CONCLUSION: HASTE sequences have the potential of improving the diagnosis of focal liver lesions.


Asunto(s)
Quistes/diagnóstico , Hepatopatías/diagnóstico , Neoplasias Hepáticas/diagnóstico , Hígado/patología , Imagen por Resonancia Magnética/métodos , Adenoma/diagnóstico , Adulto , Anciano , Artefactos , Quistes/diagnóstico por imagen , Quistes/patología , Femenino , Hemangioma/diagnóstico , Hematoma/diagnóstico , Humanos , Hiperplasia , Hígado/diagnóstico por imagen , Hepatopatías/diagnóstico por imagen , Hepatopatías/patología , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
20.
Rofo ; 164(5): 394-400, 1996 May.
Artículo en Alemán | MEDLINE | ID: mdl-8634400

RESUMEN

PURPOSE: Preoperative assessment of adnexal lesions as benign or malignant by MRI with gastrointestinal and intravenous contrast. METHODS: 46 patients with benign (n = 42) and malignant (n = 4) cystic adnexal tumours underwent MRI of the pelvis. Transaxial and coronal images were acquired using conventional T1- and T2-weighted SE-sequences after oral administration of superparamagnetic iron oxide particles (Ferristene). Additional T1-weighted SE-images were obtained immediately following gadodiamide (Gd DTPA-BMA) injection. RESULTS: MRI correctly classified the four malignant lesions, whereas nine histologically benign lesions were misdiagnosed as malignant. Intravenous contrast yielded a superior delineation of intratumor architecture. CONCLUSION: Due to exclusion of solid structures. MRI with oral and i.v. contrast enables to dismiss suspected malignity in cystic adnexal lesions. Because of the non-specificity of the macroscopic criteria of dignity, the MR diagnosis "malignity" is of limited value.


Asunto(s)
Gadolinio DTPA , Imagen por Resonancia Magnética/métodos , Neoplasias Ováricas/diagnóstico , Adenocarcinoma/diagnóstico , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Cistadenocarcinoma/diagnóstico , Cistadenocarcinoma/patología , Cistoadenoma/diagnóstico , Cistoadenoma/patología , Diagnóstico Diferencial , Femenino , Gadolinio , Humanos , Aumento de la Imagen , Inyecciones Intravenosas , Persona de Mediana Edad , Compuestos Organometálicos , Quistes Ováricos/diagnóstico , Quistes Ováricos/patología , Neoplasias Ováricas/patología , Neoplasias Ováricas/cirugía , Ovario/patología , Ácido Pentético/análogos & derivados , Cuidados Preoperatorios
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