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1.
Hautarzt ; 65(11): 974-7, 2014 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-25217085

RESUMEN

A 71-year-old man presented with giant basal cell carcinoma on the abdomen which had metastasized. He was treated with oral vismodegib. Both the primary ulcerated tumor on the abdomen and the metastases responded. Vismodegib was well tolerated without significant side effects. The tumor recurred promptly after vismodegib was discontinued, and then was resistant to therapy when vismodegib was re-administered.


Asunto(s)
Anilidas/administración & dosificación , Carcinoma Basocelular/tratamiento farmacológico , Carcinoma Basocelular/secundario , Recurrencia Local de Neoplasia/tratamiento farmacológico , Piridinas/administración & dosificación , Enfermedades de la Piel/tratamiento farmacológico , Enfermedades de la Piel/patología , Administración Oral , Anciano , Antineoplásicos/administración & dosificación , Carcinoma Basocelular/patología , Humanos , Masculino , Recurrencia Local de Neoplasia/patología , Resultado del Tratamiento
2.
J Neurosurg Sci ; 57(4): 307-16, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24091434

RESUMEN

AIM: New techniques for biological repair in the treatment of degenerative disc disease (DDD) have been developed recently. The question arises whether it is possible to find a predictive marker to identify a patient population which could benefit from this new treatment option. Standard magnetic resonance imaging (MRI) fails to differentiate between pathologic painful and asymptomatic aging discs. Neurological symptoms contribute to identifying the pathological level. In this preliminary translational research study we analysed the gene expression of structure proteins and inflammatory mediators as well as histological features of lumbar intervertebral discs in symptomatic patients with various signs of degeneration in the MRI. METHODS: Specimens of intervertebral disc tissue were obtained from 20 patients undergoing lumbar nucleotomy. Preoperatively, a group selection based on four pre-defined MRI-criteria was performed: Group 1 (mild signs of degeneration), group 2 (moderate), group 3 (moderate-severe), group 4 (severe). RESULTS: An increase of the expression of structural proteins and inflammatory markers could be observed in MRI-groups 2 and 3. Gene expression of collagen type I and II and aggrecan went along with levels of cyclooxygenase-2 (COX-2) and (fibroblast growth factor-2) FGF-2 expression. Histological examination showed signs of granulation tissue in only 35% of cases, but no differences between the groups. CONCLUSION: Our findings implicate that the gene expression of structural proteins might correlate with the appearance of inflammatory mediators in symptomatic patients with moderate disc changes in the MRI in this preliminary clinical subset. The assessment of cell activity and protein expression in a larger number of patients could be next step to support and supplement the present data.


Asunto(s)
Degeneración del Disco Intervertebral/genética , Desplazamiento del Disco Intervertebral/genética , Disco Intervertebral/metabolismo , Adulto , Anciano , Biomarcadores/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Femenino , Factor 2 de Crecimiento de Fibroblastos/genética , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Expresión Génica , Humanos , Disco Intervertebral/cirugía , Degeneración del Disco Intervertebral/metabolismo , Degeneración del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/metabolismo , Desplazamiento del Disco Intervertebral/cirugía , Masculino , Persona de Mediana Edad
3.
Cancer Res ; 56(20): 4686-93, 1996 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-8840985

RESUMEN

Anticancer drugs reversibly bound to magnetic fluids (ferrofluids) could be concentrated in locally advanced tumors by magnetic fields that are arranged at the tumor surface outside of the organism. If certain requirements are met, systemic toxicity might be minimized, and local tumor efficacy might be increased. We have conducted a Phase I clinical trial using this approach in patients with advanced and unsuccessfully pretreated cancers or sarcomas. Nine such patients received two treatment courses, 3 patients received one course, and 2 patients received three courses of magnetic drug targeting consisting of the infusion of epirubicin in increasing doses (from 5 to 100 mg/m2) that had been chemically bound to a magnetic fluid and the application of magnetic fields to the tumors for 60-120 min. In 2 of 14 patients, the same dose of epirubicin not bound to a magnetic fluid was administered systemically 3 weeks after drug targeting for intraindividual comparisons. Magnetic drug targeting with epirubicin was well tolerated. In one case, a planned second treatment was withdrawn, because of an episode of chills 130 min after infusion of the magnetic drug. Two patients received a third treatment because of good responses after the first two therapies. Based on magnetic resonance tomographic techniques, pharmacokinetics, and the histological detection of magnetites, it was shown that the ferrofluid could be successfully directed to the tumors in about one-half of the patients. Organ toxicity did not increase with the treatment, but epirubicin-associated toxicity appeared at doses greater than 50 mg/m2. Although treatment with magnetic drug targeting seems safe, improvements are necessary to make it more effective and independent of patient- or disease-related problems. A study design to compare conventional treatments with the new treatment form within one patient seems crucial to eliminate interindividual differences.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos , Epirrubicina/administración & dosificación , Magnetismo/uso terapéutico , Neoplasias/tratamiento farmacológico , Adolescente , Adulto , Anciano , Antibióticos Antineoplásicos/efectos adversos , Antibióticos Antineoplásicos/farmacocinética , Epirrubicina/efectos adversos , Epirrubicina/farmacocinética , Femenino , Ferritinas/sangre , Humanos , Hierro/sangre , Masculino , Persona de Mediana Edad , Neoplasias/sangre
4.
Rofo ; 177(2): 217-28, 2005 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-15666230

RESUMEN

PURPOSE: To compare several morphometric parameters in MRI with the functional status of the articular disc in a large patient group suffering from internal derangement (ID) of the temporomandibular joint (TMJ). MATERIALS AND METHODS: In a retrospective study, 320 analyzable high resolution MRI examinations of the TMJs obtained in a 1.5 T unit were evaluated in 184 patients with clinically suspected ID. The analysis included the anatomical structures and a number of morphometric parameters previously described in the literature. The parameters were compared with the position of the articular disc. RESULTS: The disc position was categorized as "normal" (NDP, 21.9 %, n = 70), "anterior displacement with reduction on opening" (AMR, 51.6 %, n = 165) and "anterior displacement without reduction on opening" (AOR, 26.6 %, n = 85). With increasing disc displacement, significant configurational changes of the disc were observed. Disc displacement was associated with changes of the condyle consisting of increasing deformity and other degenerative changes. A large tuberculum and marked inclination of the eminence can be seen as predisposition for the development of ID. With increasing severity of the ID, the position of the condyle moved from a centric position of the condylar center to an excentric (dorsal and cranial) position. CONCLUSION: MRI demonstrated that increasing disc displacement is associated with changes of the disc, condyles and condylar position in the fossa.


Asunto(s)
Trastornos de la Articulación Temporomandibular/diagnóstico , Articulación Temporomandibular/anatomía & histología , Cartílago Articular/anatomía & histología , Humanos , Imagen por Resonancia Magnética , Valores de Referencia , Estudios Retrospectivos , Sensibilidad y Especificidad
5.
AJNR Am J Neuroradiol ; 20(7): 1318-21, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10472992

RESUMEN

We present the case of a 57-year-old patient who was admitted to the hospital for preoperative cerebral angiography because of an intraspinal mass at the level of C1 and C2. Angiographic examination revealed an abnormal origin of the right vertebral artery, which normally originates from the right subclavian artery. Thus, the right vertebral artery was the last branch of the supraaortic vessels. We also review herein the incidence of the various anomalous origins of the right vertebral artery in the literature and discuss their potential embryologic development and clinical significance.


Asunto(s)
Arteria Subclavia/anomalías , Arteria Vertebral/anomalías , Angiografía Cerebral , Humanos , Masculino , Persona de Mediana Edad , Arteria Subclavia/diagnóstico por imagen , Arteria Vertebral/diagnóstico por imagen
6.
AJNR Am J Neuroradiol ; 18(9): 1788-90, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9367333

RESUMEN

MR imaging with retrobulbar anesthesia was performed in eight patients with uveal melanoma. Injection of 2 mL prilocain hydrochloride in 2% epinephrin into the eye muscle cone resulted in improved image quality in seven patients, without side effects. Ocular MR imaging can be indicated to clarify indeterminate sonographic findings in cases of extrascleral growth or to exclude optic nerve invasion in patients with tumors located at the posterior pole of the globe.


Asunto(s)
Anestesia Local , Epinefrina , Ojo/patología , Imagen por Resonancia Magnética , Melanoma/diagnóstico , Prilocaína , Neoplasias de la Úvea/diagnóstico , Artefactos , Humanos , Aumento de la Imagen
7.
AJNR Am J Neuroradiol ; 19(1): 91-4, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9432163

RESUMEN

PURPOSE: The purpose of this study was to ascertain whether MR imaging, with the use of a surface coil, can accurately show small intraorbital structures; in particular, the septum orbitale. METHODS: Examinations of 26 patients who underwent unilateral orbital high-resolution MR imaging for different indications were evaluated to differentiate the septum orbitale from related structures, such as the aponeurosis of the levator palpebrae, the superior tarsal (Müller's) muscle, and the superior orbital (Whitnall's) ligament. RESULTS: A subtle differentiation of the septum orbitale was obtained in 23 patients (88%) and of the levator aponeurosis and Müller's muscle in 24 patients (92%). The orbicularis oculi muscle and the submuscular fibroadipose tissue were reliably identified in all patients. CONCLUSIONS: High-resolution MR imaging is suitable for differentiating small intraorbital structures. Nevertheless, an exact depiction of the septum orbitale remains very much dependent on the cooperation of the patient. The site of orbital disease can be determined precisely and in a noninvasive manner in relation to the septum orbitale.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Órbita/anatomía & histología , Anciano , Carcinoma de Células Escamosas/diagnóstico , Quiste Dermoide/diagnóstico , Neoplasias de los Párpados/diagnóstico , Humanos , Linfangioma/diagnóstico , Persona de Mediana Edad , Enfermedades Orbitales/diagnóstico , Neoplasias Orbitales/diagnóstico , Estudios Retrospectivos
8.
AJNR Am J Neuroradiol ; 19(8): 1441-7, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9763374

RESUMEN

BACKGROUND AND PURPOSE: The aim of this study was to establish the MR imaging characteristics of choroidal hemangioma and to compare them with those of uveal melanoma. METHODS: Among 41 patients examined at 1.5 T (4-cm surface coil, T1-weighted and fast spin-echo T2-weighted sequences), 25 had uveal melanoma and 16 had circumscribed choroidal hemangioma. After i.v. bolus injection of gadopentetate dimeglumine, dynamic and T1-weighted sequences were acquired. RESULTS: In patients with choroidal hemangioma, uniform signal characteristics were detected on fast T2-weighted images. In 15 of 16 patients with choroidal hemangioma, lesions were isointense with vitreous on fast spin-echo T2-weighted images, whereas lesions in 24 of 25 patients with uveal melanoma were hypointense. Signal characteristics of uveal melanoma and hemangioma did not differ significantly on plain T1-weighted images. Enhancement was earlier and much stronger for circumscribed choroidal hemangioma than for uveal melanoma. After i.v. bolus application of gadopentetate dimeglumine, the increase of signal intensity was higher for circumscribed choroidal hemangioma (signal intensity ratio, 5.8) than for uveal melanoma (signal intensity ratio, 2.2). CONCLUSION: Circumscribed choroidal hemangioma may be difficult to differentiate from melanoma by ophthalmologic examination. Differentiation may not be possible if direct viewing of uveal space-occupying lesions is hampered by opaque vitreous media. The characteristic findings on fast spin-echo T2-weighted MR images and early enhanced images aid in differentiating choroidal hemangioma from uveal melanoma.


Asunto(s)
Neoplasias de la Coroides/diagnóstico , Hemangioma/diagnóstico , Imagen por Resonancia Magnética , Melanoma/diagnóstico , Neoplasias de la Úvea/diagnóstico , Adolescente , Adulto , Niño , Coroides/patología , Medios de Contraste , Diagnóstico Diferencial , Femenino , Gadolinio DTPA , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Úvea/patología
9.
Br J Ophthalmol ; 87(3): 330-5, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12598449

RESUMEN

BACKGROUND/AIMS: Diagnosis of retinoblastoma is mainly based on indirect ophthalmoscopy, but additional imaging techniques are indispensable for the staging of the disease. A new high resolution magnetic resonance imaging (MRI) technique for the examination of the eye was evaluated. A new surface coil with a diameter of 5 cm allows a field of view of 60 mm with an in-plane resolution of 0.8 mm. We compared preoperative MRI scans with the histology after enucleation in 21 cases of retinoblastoma. Parameters studied were appearance of retinoblastoma, choroidal and scleral infiltration, extraocular extension, optic nerve infiltration, and vitreous seeding. RESULTS: All retinoblastomas could be visualised as hypointense to vitreous on T2 weighted images and slightly hyperintense to vitreous on plain T1 weighted images with a moderate enhancement after contrast application. Histology revealed seven cases with infiltration of the optic disc or optic nerve. Preoperative MRI scans depict juxtapapillary tumour masses, but it was impossible to differentiate between a juxtapapillary retinoblastoma, a prelaminar infiltration of the optic disc, or a just postlaminar optic nerve infiltration. In five of 14 cases with a proved tumour infiltration of the choroid, MRI scans showed an inhomogeneous contrast enhancement of the choroid in enhanced T1 weighted sequences beneath the retinoblastoma. Whether this sign is specific for a choroidal infiltration or is just an artefact remains unclear. High resolution MRI scans did not allow the exclusion of this form of intraocular tumour extension. All nine cases with proved vitreous seeding were not detected by MRI scans. None of these cases showed scleral infiltration or orbital tumour extension. Therefore, it is not possible to judge the rank of this technique in detecting orbital tumour growth. CONCLUSION: The new MRI technique is of limited value in visualisation of prelaminar or postlaminar infiltration of the optic nerve. Advanced choroidal infiltration might be visualised by contrast enhanced T1 weighted MRI scans, but the available spatial resolution did not allow the exclusion this critical form of tumour growth by MRI scans. Nevertheless, high resolution MRI with the new surface coil has superior contrast and spatial resolution compared to computed tomograph (CT) or other available imaging techniques. MRI cannot replace CT in detecting tumour calcification but with increasing experience with this new technique it should be possible to renounce CT scans in the majority of cases of retinoblastoma.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Neoplasias de la Retina/diagnóstico , Retinoblastoma/diagnóstico , Niño , Preescolar , Neoplasias de la Coroides/diagnóstico , Neoplasias de la Coroides/patología , Humanos , Lactante , Invasividad Neoplásica , Disco Óptico/patología , Nervio Óptico/patología , Neoplasias del Nervio Óptico/diagnóstico , Neoplasias del Nervio Óptico/patología , Neoplasias de la Retina/patología , Retinoblastoma/patología , Esclerótica/patología , Cuerpo Vítreo/patología
10.
Rofo ; 176(12): 1819-25, 2004 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-15573294

RESUMEN

The personal digital assistant (PDA) enables the independent access to large data in a pocket-sized format. The applications for hand-held computers are growing steadily and can support almost any kind of problem. An overview of the available hardware and software is provided and evaluated. Furthermore, the use of the PDA in the clinical daily routine is described. In view of the numerous software programs available in radiology, the range of software solutions for radiologists is presented. Despite the high acquisition cost, the PDA has already become the digital assistant for the radiologist. After a short time of getting used to the PDA, nobody wants to miss it at work or at home. New technical features and available software programs will continuously increase the integration of the PDA into the medical workflow in the near future.


Asunto(s)
Computadoras de Mano , Radiología/tendencias , Computadores , Computadoras de Mano/estadística & datos numéricos , Humanos , Radiología/educación , Programas Informáticos , Evaluación de la Tecnología Biomédica
11.
Rofo ; 161(5): 391-8, 1994 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-7948992

RESUMEN

In a prospective study the value of spiral CT for the detection and differential diagnosis of intraorbital masses was investigated. Thirty patients with various orbital diseases were examined with transverse spiral computed tomography. After performing two contiguous 1 mm spiral CT scans, coronal, parasagittal, and other reconstructions were obtained. Compared with separately generated 2 mm slices, the 1 mm spiral CT images showed a slightly decreased signal-to-noise ratio, but due to the better spatial resolution, the image quality of secondary reconstructions was similar to that of the original transverse spiral CT slices. Generally the orbital masses were visualized best in the coronal reconstruction. In certain cases, the parasagittal reconstructions were superior. Reconstructions in freely definable slice planes based on 1 mm spirals provides better visualization of orbital diseases without increasing radiation dose. This method allows multiplanar reconstructions similar to magnetic resonance tomography.


Asunto(s)
Órbita/diagnóstico por imagen , Neoplasias Orbitales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Diagnóstico Diferencial , Femenino , Humanos , Yohexol/análogos & derivados , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Dosis de Radiación , Tomografía Computarizada por Rayos X/instrumentación , Tomografía Computarizada por Rayos X/normas
12.
Rofo ; 176(12): 1811-8, 2004 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-15573293

RESUMEN

PURPOSE: To evaluate the feasibility and the clinical benefits of retrospective digital image fusion (PET, SPECT, CT and MRI). MATERIALS AND METHODS: In a prospective study, a total of 273 image fusions were performed and evaluated. The underlying image acquisitions (CT, MRI, SPECT and PET) were performed in a way appropriate for the respective clinical question and anatomical region. Image fusion was executed with a software program developed during this study. The results of the image fusion procedure were evaluated in terms of technical feasibility, clinical objective, and therapeutic impact. RESULTS: The most frequent combinations of modalities were CT/PET (n = 156) and MRI/PET (n = 59), followed by MRI/SPECT (n = 28), CT/SPECT (n = 22) and CT/MRI (n = 8). The clinical questions included following regions (more than one region per case possible): neurocranium (n = 42), neck (n = 13), lung and mediastinum (n = 24), abdomen (n = 181), and pelvis (n = 65). In 92.6 % of all cases (n = 253), image fusion was technically successful. Image fusion was able to improve sensitivity and specificity of the single modality, or to add important diagnostic information. Image fusion was problematic in cases of different body positions between the two imaging modalities or different positions of mobile organs. In 37.9 % of the cases, image fusion added clinically relevant information compared to the single modality. CONCLUSION: For clinical questions concerning liver, pancreas, rectum, neck, or neurocranium, image fusion is a reliable method suitable for routine clinical application. Organ motion still limits its feasibility and routine use in other areas (e. g., thorax).


Asunto(s)
Fluorodesoxiglucosa F18 , Aumento de la Imagen , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Radiofármacos , Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Postura , Estudios Prospectivos , Sensibilidad y Especificidad , Programas Informáticos
13.
Rofo ; 176(11): 1607-16, 2004 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-15497079

RESUMEN

PURPOSE: The characterization of different liver tumors is of therapeutic and prognostic relevance and has been the purpose of several studies. Although ultrasound offers the opportunity to detect hepatic tumors without ionizing radiation, its previous techniques did not lead toward a definitive differentiation of different tumor entities. The purpose of this study was the clinical evaluation of contrast enhanced ultrasound followed by quantitative digital analysis in patients with focal hepatic tumors. MATERIALS AND METHODS: In a prospective study, 50 patients (18 females, 32 males, age 28 to 83 years, mean age 59.4 years) with liver tumors previously detected by CT (n = 47) or MRI (n = 3) were examined by ultrasound of the upper abdomen using conventional technique and phase inversion technique after intravenous application of sulfur-based contrast enhancer SonoVue. At scheduled intervals after application of the contrast enhancer, a digital image was stored and the characteristic signal course of each lesion determined semiquantitatively. The gold standard was either resection (n = 17), percutaneous needle biopsy (n = 19) or the clinical course (n = 14). RESULTS: While the percentage of tumors correctly characterized by CT/MRI amounted to 78 %, the percentage increased from 60 % using conventional ultrasound to 86 % using contrast enhanced ultrasound including grey-scale analysis. Typical graphs were achieved for different tumor entities on digital grey-scale analysis. The optimal intervals for the differentiation of particular entities were 20 and 100 seconds after injection. CONCLUSION: Quantification of contrast enhanced ultrasound is an addition to the previous diagnostic procedure in hepatic tumors. It offers the possibility of an investigator-independent characterization of lesions and should be evaluated in further studies.


Asunto(s)
Adenoma de Células Hepáticas/diagnóstico por imagen , Carcinoma Hepatocelular/diagnóstico por imagen , Colangiocarcinoma/diagnóstico por imagen , Hiperplasia Nodular Focal/diagnóstico por imagen , Hemangioma/diagnóstico por imagen , Aumento de la Imagen/métodos , Neoplasias Hepáticas/diagnóstico por imagen , Fosfolípidos , Hexafluoruro de Azufre , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Sensibilidad y Especificidad , Ultrasonografía
14.
Rofo ; 164(2): 114-8, 1996 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-8679972

RESUMEN

PURPOSE: Assessment of the functional diagnostic value of Doppler sonographic or sonographic parameters, especially of the peak flow velocity in the inferior thyroid artery in patients with newly manifest autoimmunothyroiditis. MATERIAL AND METHOD: Morphological and Doppler sonographic measurements were done at the inferior thyroid artery on 69 patients suffering from newly manifest Graves' disease or Hashimoto's thyroiditis, as well as on a control group of 18 subjects. The measured data were correlated with thyroid hormone levels and with quantitative scintiscanning. RESULTS: A linear functional correlation was found between the peak flow velocities in the inferior thyroid artery and the fT3 or fT4 level. If the peak flow velocities were greater than 1.2 m/s, hyperthyroid metabolism prevailed, whereas at velocities below 0.3 m/s latent hypothyroidism was present. CONCLUSION: These results show that Doppler sonography of the inferior thyroid artery can supply pointers (capable of being recorded) to the state of functioning of the thyroid even before knowing the laboratory parameters.


Asunto(s)
Glándula Tiroides/diagnóstico por imagen , Adulto , Anciano , Arterias/diagnóstico por imagen , Velocidad del Flujo Sanguíneo , Enfermedad de Graves/diagnóstico por imagen , Enfermedad de Graves/fisiopatología , Humanos , Persona de Mediana Edad , Pruebas de Función de la Tiroides/métodos , Glándula Tiroides/irrigación sanguínea , Glándula Tiroides/fisiopatología , Tiroiditis Autoinmune/diagnóstico por imagen , Tiroiditis Autoinmune/fisiopatología , Ultrasonografía Doppler Dúplex/instrumentación , Ultrasonografía Doppler Dúplex/métodos
15.
Rofo ; 175(9): 1232-8, 2003 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-12964079

RESUMEN

PURPOSE: Due to the shortage of cadaver donors, living related liver donation (LRLD) has emerged as an alternative to cadaver donation. The expected graft weight is one of the main determinants for donor selection. This study investigates the accuracy of preoperatively performed CT-volumetry to predict the actual weight of the right liver lobe graft. MATERIALS AND METHODS: In a prospective study the weight of the right hepatic lobe was calculated by volumetric analysis based on CT in 33 patients (21 females, 12 males, mean age 42.1 years, median age 41 years) prior to living related liver donation. Graft weight was calculated as the product of CT-based graft volume and 1.00 g/ml (the approximated density of healthy liver parenchyma). The calculated weight was compared with the intraoperatively measured weight of the harvested right hepatic lobe. The difference was used to determine a correction factor for estimating the actual graft weight. RESULTS: Based on the assumption of a parenchymal density of 1.00 g/ml, the preoperatively estimated graft weight (mean 980 g +/- 168 g) deviated +33 % from the intraoperatively measured right hepatic lobe weight (mean 749 g +/- 170 g). By reducing the preoperatively predicted weight of the right hepatic lobe with a correction factor of 0.75, the actual graft weight can be calculated. CONCLUSION: Preoperative estimation of the weight of the right hepatic lobe based on CT of living related liver donors predicts the weight of the right lobe graft with sufficient accuracy by applying a single correction factor. Intraoperative fluid loss (i.e., blood, bile) from the harvested liver as well as variations in parenchymal density may contribute to the observed preoperative overestimation of the actual graft volume by CT-based volumetry.


Asunto(s)
Trasplante de Hígado , Hígado/diagnóstico por imagen , Donadores Vivos , Recolección de Tejidos y Órganos , Adulto , Anciano , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Estudios Prospectivos , Tomografía Computarizada por Rayos X
16.
Rofo ; 176(10): 1436-46, 2004 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-15383975

RESUMEN

PURPOSE: Over the last decade, MRI has become the standard procedure for the diagnosis of orbital masses. Purpose of the study was to evaluate criteria for differential diagnosis for intraconal masses on MRI in a large patient group. MATERIAL AND METHODS: In a retrospective study, MR examinations of 78 patients with intraconal masses were evaluated. All examinations were performed using surface coils for high spatial resolution. Signal behavior on T2-WI and T1-WI before and after contrast application as well as further tumor characteristics (i. e., shape, size, position, delineation and infiltration) were evaluated. Every diagnosis was proven by histopathological results from extirpation (n = 18) or biopsy (n = 22), or confirmed by other imaging modalities (n = 13) or clinical course (n = 25). RESULTS: Different tumor characteristics are helpful in the differentiation between cavernous hemangioma, lymphangioma, varices, AV malformations and solid tumors. Due to overlapping in the imaging appearance, the differentiation between inflammatory pseudotumor, lymphoma and orbital metastasis was more difficult. CONCLUSION: While high resolution MRI using surface coils allows differentiation between the typical vascular tumors, the differentiation between solid tumors is more difficult. Thus, a histopathologic verification of the diagnosis is necessary in solid tumors.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Neoplasias Orbitales/diagnóstico , Adolescente , Adulto , Anciano , Malformaciones Arteriovenosas/diagnóstico , Malformaciones Arteriovenosas/patología , Biopsia , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Hemangioma Cavernoso/diagnóstico , Hemangioma Cavernoso/patología , Humanos , Lactante , Linfangioma/diagnóstico , Linfangioma/patología , Linfoma/diagnóstico , Linfoma/patología , Masculino , Persona de Mediana Edad , Órbita/patología , Enfermedades Orbitales/diagnóstico , Enfermedades Orbitales/patología , Neoplasias Orbitales/patología , Neoplasias Orbitales/secundario , Neoplasias Orbitales/cirugía , Seudotumor Orbitario/diagnóstico , Seudotumor Orbitario/patología , Estudios Retrospectivos , Factores de Tiempo , Várices/diagnóstico , Várices/patología
17.
Rofo ; 167(6): 591-8, 1997 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-9465954

RESUMEN

PURPOSE: The purpose of the study was to investigate the use and safety of Gadobutrol, a new low-osmolar, non-ionic contrast agent for MRI using a total dose of 0.3 mmol/kg b.w. on the basis of a clinical phase 3 study. METHODS: 30 patients with primary brain tumours (n = 15) or cerebral metastases (n = 15) were examined via MRI before and after application of a total of 0.3 mmol/kg b.w. given in two fractions (0.1 and 0.2 mmol/kg b.w.). T2-weighted images were performed before, T1-weighted images before, between and after application of contrast material. RESULTS: In this study one-molar Gadobutrol showed a good tolerance. In half of the cases the contrast between lesion and brain was improved comparing single and triple dose, but this means only a slightly improvement of information for the primary brain tumours compared with single dose. The detected metastatic lesions increased in 40% of the patients after the single dose and in 53% of the patients after cumulative triple dose. There was a consecutive change in therapy in 20% of the patients. CONCLUSION: For the differentiation of primary brain tumours the single dose was sufficient, in metastatic lesions triple dose was essential for the detection or exclusion of multifocality.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Medios de Contraste , Gadolinio , Imagen por Resonancia Magnética/métodos , Compuestos Organometálicos , Adenoma/diagnóstico , Adulto , Anciano , Astrocitoma/diagnóstico , Neoplasias Encefálicas/secundario , Medios de Contraste/administración & dosificación , Craneofaringioma/diagnóstico , Femenino , Gadolinio/administración & dosificación , Hemangioblastoma/diagnóstico , Humanos , Masculino , Meningioma/diagnóstico , Persona de Mediana Edad , Oligodendroglioma/diagnóstico , Compuestos Organometálicos/administración & dosificación , Neoplasias Hipofisarias/diagnóstico , Seguridad
18.
Rofo ; 169(5): 471-8, 1998 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-9849595

RESUMEN

PURPOSE: Choroidal melanomas usually present a characteristic appearance in MRI. Differing characteristics can cause problems in differential diagnosis between melanomas and other masses in the globe. The purpose of this study was to evaluate the appearance of choroidal melanomas with MRI in a large consecutive patient group. METHODS: In a prospective study, 200 patients with choroidal melanomas were investigated with MRI using a 1.5 T scanner and a 5 cm surface coil. Both quantitative and qualitative evaluation of the resulting images was performed. RESULTS: 78.5% of the melanomas presented with homogeneous signal intensities within the tumor due to a homogeneous pigmentation whereas 21.5% of the melanomas demonstrated a mixed pigmentation. Signal intensities of the homogeneous melanomas in the plain T1-WI were moderately or markedly hyperintense compared to the vitreous in 29.3% and moderately or markedly hypointense in the T2-WI in 37.1%. An accompanying retinal detachment was found in 65.5% and an extraocular growth in 7.0%. CONCLUSIONS: In 10% to 37% we observed the typical well known MR appearance, including homogeneous high signal in the T1-WI and low signals in the T2-WI. For further differentiation, morphological criteria (e.g. shape, size, and position) were used, which are also discussed.


Asunto(s)
Neoplasias de la Coroides/diagnóstico , Imagen por Resonancia Magnética/instrumentación , Melanoma/diagnóstico , Neoplasias de la Coroides/patología , Diagnóstico Diferencial , Hemangioma/diagnóstico , Imagen por Resonancia Magnética/métodos , Melanoma/patología , Metástasis de la Neoplasia , Pigmentación , Estudios Prospectivos , Desprendimiento de Retina/complicaciones , Desprendimiento de Retina/diagnóstico
19.
Rofo ; 175(7): 958-62, 2003 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-12847651

RESUMEN

PURPOSE: The determination of tumor volume in ocular tumors is very important for the planning and success of radiation therapy. This study uses an animal model to evaluate the accuracy of MR-based volumetry of ocular tumors. MATERIALS AND METHODS: In a total of 25 porcine eyes obtained from the slaughterhouse, ocular tumors were produced by injecting a mixture of hand creme and Gd-DTPA under ophthalmoscopic guidance. The injected volume varied between 0.05 ml and 2.7 ml. The eyes were examined with a 1.5 Tesla scanner and a 4 cm circular surface coil especially developed for ocular MRI. After data transfer to a separate workstation, volumetric analysis was carried out by three independent radiologists using semiautomated software. The determined volume was compared with the injected volume. RESULTS: Of the 25 prepared porcine eyes, 23 were suitable for volumetric analysis. The injection of the mixture of hand creme and Gd-DTPA produced two different types of tumors. Ophthalmoscopically, 14 ellipsoid and 9 lobulated to mushroom-shaped tumors were found and confirmed by MRI. Minor deviation was found between injected volume and volume calculated by MRI, with a correlation coefficient of 0.96. CONCLUSION: Using appropriate technique, MRI is capable of determining small tumor volumes with high accuracy in an animal model. Minor differences can be expected when transferring the results to clinical studies.


Asunto(s)
Neoplasias del Ojo/diagnóstico , Procesamiento de Imagen Asistido por Computador/instrumentación , Imagen por Resonancia Magnética/instrumentación , Cómputos Matemáticos , Fantasmas de Imagen , Animales , Ojo/patología , Neoplasias del Ojo/patología , Humanos , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Imagen por Resonancia Magnética/estadística & datos numéricos , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Programas Informáticos , Porcinos
20.
Rofo ; 160(3): 204-9, 1994 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-8136472

RESUMEN

In this study, the possibility of non-invasive, three-dimensional demonstration of aneurysms of the basal cerebral arteries by means of spiral CT was investigated. The first step was to obtain exact definition of optimal examination parameters. Angio CTs at appropriate levels were performed on 10 subjects and time/density curves of the arterial and venous phases obtained in order to optimise the beginning of the arterial spiral CT series. The second step in this investigation was to examine 7 patients; in 6 of these basal aneurysms had been demonstrated by DSA. By means of multiplanar three-dimensional reconstruction from the data of the spiral CT it was possible to demonstrate 7 aneurysms with a diameter between 5 and 18 mm. Their position and relationship to the bony skull was also shown.


Asunto(s)
Angiografía Cerebral/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Angiografía de Substracción Digital , Angiografía Cerebral/instrumentación , Medios de Contraste , Humanos , Yohexol/análogos & derivados , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/instrumentación
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