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1.
Pneumologie ; 75(9): 644-650, 2021 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-33882609

RESUMEN

Despite growing experience due to increasing patient numbers, the intensive care treatment of patients with severe COVID-19 pneumonia continues to be a particular challenge in individual cases, which may also therefore legitimize individualized therapeutic attempts. In this context, the so-called hyperinflammation syndrome characterized by a cytokine storm accompanied by a massive increase in inflammatory markers such as interleukin(IL)-6, represents such a situation. This case report describes the therapeutic approach of using the IL-6-specific antibody tocilizumab in combination with hemoadsorption therapy (CytoSorb) in a 58-year-old male patient with severe COVID-19 pneumonia. The patient suffered a massive clinical deterioration with concomitant Horovitz index of 127 mmHg that occurred on the 6th day of ventilation. After combined application of the above-mentioned therapeutic approaches, the patient stabilized rapidly paralleled by a significant increase in the Horovitz index, and the possibility of de-escalating the ventilation regimen, which ultimately enabled successful extubation after only 13 days of ventilation. Moreover, the combined treatment was associated with significant hemodynamic stabilization and a consecutive reduction in vasopressor doses, while hyperinflammation could be kept well under control. The incorporation of the hemoadsorber into the therapeutic regimen proved to be safe and straightforward. In conclusion, the combination of CytoSorb therapy and IL-6 blockade by tocilizumab appeared, at least in this case, to be an effective measure to modulate an overshooting immune response in COVID-19 pneumonia with a concomitant clinical improvement in both respiratory and hemodynamic function, and thus could be used as a potential therapeutic option in this clinical picture.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Síndrome de Liberación de Citoquinas , Anticuerpos Monoclonales Humanizados , Humanos , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Resultado del Tratamiento
2.
Lung Cancer ; 55(2): 165-71, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17129635

RESUMEN

PURPOSE: The relevance of (18)F-FDG PET for staging non-small cell lung cancer (NSCLC), in particular for the detection of lymph node or distant metastases, has been shown in several studies. The value of FDG-PET for therapy monitoring in NSCLC, in contrast, has not yet been sufficiently analysed. Aim of this study was to evaluate FDG-PET for monitoring treatment response during and after neoadjuvant radiochemotherapy (NARCT) in advanced NSCLC. METHODS: Sixty-five patients with histologically proven NSCLC stage III initially underwent three FDG-PET investigations, during NARCT prior to initiating radiation, and post-NARCT. Changes of FDG-uptake in the primary tumour at two time-points during NARCT were analysed concerning their impact on long-term survival. RESULTS: The mean maximum FDG uptake (standardized uptake value, SUVmax) of the whole group decreased significantly during NARCT (SUVmax PET 1: 14.9+/-4.0, SUVmax PET 3: 5.5+/-2.4, p=0.004). The difference between initial FDG uptake (PET 1) and uptake after induction chemotherapy (PET 2) was found to be highly predictive for long-term survival patients which had a greater than 60% decreases in their SUV change had a significantly longer survival than those below this threshold (5-year-survival 60% versus 15%, p=0.0007). Patients who had a lower than 25% decrease in their SUV change had a 5-years-survival lower than 5%. Furthermore, the difference between initial FDG uptake (PET 1) and uptake after completion of the whole NARCT (PET 3) was predictive for survival when 75% was applied as cut-off (p=0.02). However, the level of significance was considerably lower. CONCLUSION: FDG-PET is suitable for therapy monitoring in patients with stage III NSCLC. The decrease of FDG uptake during induction chemotherapy is highly predictive for patient outcome.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Fluorodesoxiglucosa F18/farmacocinética , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/tratamiento farmacológico , Radiofármacos/farmacocinética , Adulto , Anciano , Área Bajo la Curva , Carboplatino/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Paclitaxel/uso terapéutico , Cintigrafía , Análisis de Supervivencia
3.
Am J Cardiol ; 53(4): 590-7, 1984 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-6695789

RESUMEN

The influence of heart rate on left ventricular (LV) volumes and ejection fraction (EF) using 2-dimensional (2-D) echocardiography during atrial pacing was analyzed. The study was performed in 13 normal control subjects, 23 patients with coronary heart disease and 8 patients with dilated cardiomyopathy. An electronic sector scanner (2.25 MHz, 84 degrees) was used. Under constant scanning of the left ventricle, heart rate was increased, in steps of 20 beats/min, from 80 to 140 beats/min. The 2-D echocardiograms were stored on videotape and analyzed off-line. The end-diastolic and end-systolic volumes (EDV and ESV) were determined using a disc method. Stroke volume (SV) and EF were calculated. Constant LV scanning was possible during atrial stimulation, as shown by the analysis of simultaneously recorded 2-D echocardiograms and cineventriculograms at different heart rates, revealing a constant position of the echocardiographic transducer. Simultaneous recordings of cineventriculography and 2-D echocardiography at 80 and 120 beats/min showed that despite differences in absolute values, percent changes of LV volumes and EF determined with both methods were similar. Thus, changes of LV function can be analyzed by 2-D echocardiography. In normal control subjects, an increase in heart rate of 10 beats/min reduced EDV by 4 ml, ESV by 2 ml, SV by 2 ml and EF by 1%, corresponding to percent reductions of 4, 2, 5 and -2%, respectively. In contrast, the absolute decreases in the patients were 6 ml, 1 ml, 5 ml and 2% and the percent changes 2%, 1%, 8% and 5%.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Gasto Cardíaco , Frecuencia Cardíaca , Volumen Sistólico , Adulto , Anciano , Cateterismo Cardíaco , Estimulación Cardíaca Artificial , Volumen Cardíaco , Cardiomiopatía Dilatada/fisiopatología , Enfermedad Coronaria/fisiopatología , Ecocardiografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Contracción Miocárdica
4.
Invest Radiol ; 30(7): 421-6, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7591651

RESUMEN

RATIONALE AND OBJECTIVES: Conventional intraoral radiography was compared with axial computed tomography (CT) scans for identification and classification of bony pockets in dentate jaw segments. METHODS: Fifty-five artificial bone defects were produced in six dentate jaw segments. The jaws were examined radiographically using a dental x-ray unit and by contiguous axial CT scans. Identification, classification, and vertical depth of the bony defects were compared among the specimens, radiographs, and CT scans. RESULTS: On the intraoral radiographs, 38 (69%) bony lesions were identified, and the vertical depth was underestimated by a mean of 2.2 mm, compared with the objective measurements on the jaws. In contrast, all artificial bony lesions (100%) were identified and classified on the axial CT scans and the vertical depth was underestimated by a mean of 0.5 mm. CONCLUSIONS: High-resolution CT improves the identification and metric assessment of the vertical dimension of infra-alveolar bony lesions compared with conventional intraoral x-ray films and allows these defects to be classified according to the number of existing walls into one-walled, two-walled, and three-walled bony pockets. In patients with apically extended metallic restorations, the image quality could be limited by artifacts.


Asunto(s)
Pérdida de Hueso Alveolar/diagnóstico por imagen , Proceso Alveolar/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Pérdida de Hueso Alveolar/patología , Proceso Alveolar/patología , Cefalometría , Humanos , Mandíbula/diagnóstico por imagen , Mandíbula/patología , Maxilar/diagnóstico por imagen , Maxilar/patología , Bolsa Periodontal/diagnóstico por imagen , Bolsa Periodontal/patología , Probabilidad , Intensificación de Imagen Radiográfica/métodos , Radiografía Dental , Sensibilidad y Especificidad
5.
Invest Radiol ; 28(8): 686-9, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8376000

RESUMEN

OBJECTIVES: The authors assessed the relative efficacy of conventional and digital storage-phosphor radiographs for the detection of skull fractures. METHODS: Fifty conventional film-screen radiographs (FSR) and 50 digital storage-phosphor radiographs (DR) with 66 fractures were compared. Five radiologists evaluated image quality and fracture detectability. The results were analyzed by receiver operating characteristic (ROC) curve analysis. RESULTS: With a standard exposure, the ability to evaluate skull fractures was equally good with either technique (ROC area for DR, 0.8954; for FSR, 0.8870). Digital radiography was superior in evaluating nasal bone. For petrosal bone, the DR image simulates an underexposure. This disadvantage compared with FSR can be compensated by image postprocessing. CONCLUSION: In evaluation of skull fractures, radiologists performance with DR is equivalent to FSR.


Asunto(s)
Intensificación de Imagen Radiográfica , Fracturas Craneales/diagnóstico por imagen , Cráneo/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Niño , Preescolar , Estudios de Evaluación como Asunto , Humanos , Lactante , Persona de Mediana Edad , Variaciones Dependientes del Observador , Curva ROC , Intensificación de Imagen Radiográfica/instrumentación , Fracturas Craneales/epidemiología , Pantallas Intensificadoras de Rayos X
6.
Invest Radiol ; 28(3): 231-4, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8486490

RESUMEN

RATIONALE AND OBJECTIVES: The effect of varying exposure parameters on the detectability of a fracture with digital and conventional radiography were examined. METHODS: A macerated fractured skull was imaged by film-screen radiography (FSR) and digital storage phosphor radiography (DR) with various exposure values. Five radiologists traced the course of a fracture line. The length of the fracture was reported and the results were analyzed by Student's t test for paired samples. RESULTS: At 35% of the conventional radiation dose, the standard DR screen displayed an average of 48% of the fracture length. The difference from the conventional image (45%) was not significant in this case. An increase of the dose to ten times the conventional dose (250 mAs) yielded no significant improvement in the detectability of the length of the fracture (51%). CONCLUSIONS: This experiment shows that with use of the DR with the standard screen, a dose reduction of approximately 35% appears to be possible without any resulting loss of image quality compared to FSR. Use of the high resolution screens should be avoided, since they require a higher incident image dose than standard screens without offering any diagnostic advantages. The image dose of digital radiographs can be roughly estimated based on the digital device sensitivity value. As a rule, the sensitivity value should range between 100 and 200.


Asunto(s)
Intensificación de Imagen Radiográfica , Fracturas Craneales/diagnóstico por imagen , Técnicas In Vitro , Dosis de Radiación , Sensibilidad y Especificidad
7.
Eur J Radiol ; 41(1): 19-25, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11750148

RESUMEN

OBJECTIVE: High soft-tissue contrast and multiplanar imaging capabilities of MRI may be advantageous in biopsy guidance compared to CT. We report our first results with MR-guided core biopsies using a closed 1.0 T MR imager. METHODS AND PATIENTS: In ten patients, seven liver lesions and one lesion each in the muscle of the back, the gluteal muscle and in the breast were biopsied under MR guidance using MR-compatible needles (Tru-Cut type, 18G and 14G). For control scans T1-weighted turbo-spin-echo (TSE), gradient-echo and T2-weighted TSE sequences were used. RESULTS: In all patients, the suspicious lesions and the biopsy needle were exactly delineated in MR control scans. In nine out of ten patients, the suspicious lesion was clarified histologically. Controls of needle position in a second plane were performed twice. Pushing the inner stylet alone resulted in a distortion of the needle in several cases in its flat area. The small diameter of the MR gantry was inconvenient for a few patients. One complication (intrahepatic bleeding) was observed, which healed up without consequences. CONCLUSION: Using a closed 1.0 T MR imager MR-guided core biopsies can be conducted efficiently. Core biopsies should be taken by pulling and pushing the outer cannula. Advantageous compared to CT are the multiplanar imaging capabilities, while the smaller gantry is disadvantageous.


Asunto(s)
Biopsia/métodos , Imagen por Resonancia Magnética , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Imagen por Resonancia Magnética/instrumentación , Masculino , Persona de Mediana Edad
8.
Rofo ; 170(3): 310-5, 1999 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-10230442

RESUMEN

PURPOSE: Localization of non-palpable suspicious breast lesions with tumor localization wires is commonly used before surgical excision. Dislocation of the wire is possible. The possibility of dislocation for different types of tumor localization wires was examined experimentally. METHODS: 22 different tumor localization wires were inserted into the subcutaneous fat-tissue of a pig. The wire tip was recorded under fluoroscopy. Traction was applied to the wire using a spring-balance. The artifact size of MR-compatible wires was examined in a 1.0 Tesla MR imager. RESULTS: The localization wires with an X-configuration and long hook could not be dislocated by a force up to the maximum of 12 Newton. The retractable localization wires were easily dislocated at traction forces of 1 Newton. Other wires with only one hook could withstand a traction from 2 up to 7 Newton. The wires with a Z-configuration and wires with short hooks showed a highly variable rate of resistance. The artifact size of localization systems was between 10.1 and 11.0 mm for gradient-echo sequences and between 6.7 and 7.1 mm for spin-echo sequences. CONCLUSION: Tumor localization wires with an X-configuration and long hooks were best anchored in the tissue. The advantage of repositioning retractable wires is confined by the high risk of accidental dislocation. No reliable fixation in the tissue could be achieved using wires with a Z-configuration and wires with short hooks. MR-compatible wires were comparable to non-MR-compatible wires concerning the rate of resistance. The size of the artifacts of MR-compatible systems showed no relevant differences.


Asunto(s)
Artefactos , Mama/anatomía & histología , Imagen por Resonancia Magnética/instrumentación , Tejido Adiposo/anatomía & histología , Animales , Neoplasias de la Mama/diagnóstico , Diseño de Equipo , Estudios de Evaluación como Asunto , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/estadística & datos numéricos , Porcinos
9.
Rofo ; 167(6): 645-8, 1997 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-9465962

RESUMEN

PURPOSE: To control the position of a puncture needle on an access route, which is not parallel to the CT-scan, using control scans not showing start and target points. METHODS: A software tool has been developed. After CT for biopsy planning x/y coordinates and table position of start and target points have to be determined on CT-scans. The software calculates x/y coordinates of the access route for every table position, which must be marked interactively on control scans. The accuracy of the programme was proven experimentally and the method was used in five patients. RESULTS: There was no difference between the calculated and measured access route in the experiment. Four of five patients were punctured successfully using our method. CONCLUSION: Our method is a promising procedure to control a CT-guided caudo-cranial biopsy access route.


Asunto(s)
Biopsia con Aguja/métodos , Tomografía Computarizada por Rayos X/métodos , Humanos , Hígado/patología , Absceso Hepático Amebiano/diagnóstico , Absceso Hepático Amebiano/patología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Modelos Teóricos , Fantasmas de Imagen , Postura , Programas Informáticos , Absceso Subfrénico/diagnóstico , Absceso Subfrénico/patología , Teratocarcinoma/diagnóstico , Teratocarcinoma/patología , Teratocarcinoma/secundario
10.
Rofo ; 150(5): 582-7, 1989 May.
Artículo en Alemán | MEDLINE | ID: mdl-2541486

RESUMEN

37 cases of skull fractures with involvement of the orbit were reviewed retrospectively. The value of plain films, tomography and computed tomography was analysed. Combined use of 28 degrees Caldwell and water views revealed 96% of all orbital floor fractures. Orbital emphysema in facial bone fractures nearly almost (in 14 of 15 cases) indicated involvement of the medial orbital wall. CT--performed on a biplane basis--showed best diagnostic accuracy in evaluating orbital fractures. Axial CT scans revealed only 70% of all orbital floor fractures. Because of that coronal scans are especially necessary for evaluating the orbital floor and the orbital roof. CT is necessary for evaluating the medial orbital wall since conventional radiology only shows 15% of all medial orbital wall fractures.


Asunto(s)
Fracturas Orbitales/diagnóstico por imagen , Fracturas Craneales/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Órbita/diagnóstico por imagen , Estudios Retrospectivos , Cráneo/diagnóstico por imagen , Tomografía por Rayos X
11.
Rofo ; 154(1): 5-10, 1991 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-1846694

RESUMEN

To demonstrate the detailed vascular architecture of the skin, barium sulphate suspension was injected into the arteries of nine amputated lower limbs. Sections of skin from the foot were fixed in formalin and embedded in paraffin and then examined by high resolution radiography. Subsequently histological sections were prepared and correlated with the micro-angiographic appearances. This technique provided demonstration of the detailed vascular structure of the skin with very little super imposition. The capillary loops in the papillae, the sub-papillary plexus, the glandular components (with the capillaries surrounding the sweat glands), the fine arteries and smallest veins in the cutis could be demonstrated over a prolonged course. Microangiographic and histologic sections were carried out in parallel. These eliminated artifacts and clarified the micro-angiographic appearances. The value of microangiography for demonstrating the vascularity of the skin under normal, pathological and experimental conditions is the subject of further studies.


Asunto(s)
Pierna/irrigación sanguínea , Microrradiografía , Piel/irrigación sanguínea , Anciano , Anciano de 80 o más Años , Angiografía , Sulfato de Bario/administración & dosificación , Femenino , Humanos , Técnicas In Vitro , Inyecciones Intraarteriales , Pierna/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Piel/diagnóstico por imagen
12.
Rofo ; 154(6): 582-6, 1991 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-1648759

RESUMEN

Conventional screen-film radiographs were compared with storage phosphorus images concerning diagnostic performance in traumatologic radiography. We used an image pool of 106 radiographs including 50 conventionally and 56 digitally recorded images. The images were reviewed by four experienced radiologists. Detectability of fractures was coded in a five-point scale of confidence and analysed by ROC statistics. Furthermore the image quality and the optical density was compared. Digital images are superior under difficult exposure conditions and offer advantages by additional image processing and documentation. For some indications (follow-up, functional examination), reduced x-ray exposure is tolerable. The detectability of subtle lesions, which is essential for the primary diagnosis of fractures was significantly better by conventional radiography.


Asunto(s)
Fracturas Óseas/diagnóstico por imagen , Traumatismos de la Pierna/diagnóstico por imagen , Mediciones Luminiscentes , Intensificación de Imagen Radiográfica/métodos , Estudios de Evaluación como Asunto , Humanos , Control de Calidad , Curva ROC , Dosis de Radiación , Intensificación de Imagen Radiográfica/instrumentación , Pantallas Intensificadoras de Rayos X
13.
Rofo ; 173(7): 658-62, 2001 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-11512240

RESUMEN

PURPOSE: Comparative evaluation of specimens obtained with different MR-compatible biopsy systems and a conventional ferromagnetic system. METHODS: Biopsies of a pig liver were performed post-mortem with three different MR-compatible (Somatex; E-Z-EM; Daum) and one conventional biopsy system (Somatex), five with each device. The specimens were measured and the histopathological quality was graded on a scale from 0 (no tissue) to 9 (best). The tip of the needle was examined with an electron microscope before and after biopsy to demonstrate abrasion. RESULTS: The histopathological score between the first and fifth specimen taken with one biopsy device showed no significant difference. The conventional system yielded significantly better results in nearly all categories (p < 0.05) than the MR-compatible biopsy systems. The areas of the specimens obtained with the MR-compatible biopsy systems (4.27-5.99 mm2) were significantly smaller than those from the conventional system (9.98 mm2). The needle tip abrasion of the different biopsy systems determined by electron microscopy showed no substantial difference. CONCLUSION: Specimens obtained with MR-compatible biopsy systems compared to conventional biopsy systems are of lower histopathological quality. This might be caused by a smaller side notch of the MR-compatible biopsy devices. There was no difference in abrasion of the needle tip due to the softer, non-ferromagnetic alloys.


Asunto(s)
Biopsia con Aguja/instrumentación , Compuestos Férricos , Hígado/patología , Imagen por Resonancia Magnética/instrumentación , Animales , Diseño de Equipo , Análisis de Falla de Equipo , Microscopía Electrónica , Propiedades de Superficie , Porcinos
14.
Rofo ; 167(5): 501-8, 1997 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-9440897

RESUMEN

PURPOSE: To evaluate accuracy of needle localisation using and signal enhancement on a 1.OT MR imager for various needles for MR-guided biopsy. METHODS: The differences between actual and virtual needle position of needles with different orientations were evaluated in a phantom for spin-echo including turbo-spin-echo sequences. RESULTS: Artifacts depended on the orientation of the needle relative to the field B0, frequency-encoding gradients (Gf) and slice orientation. This resulted in different artifact shapes and sizes for left or right and cranial or caudal biopsy access routes. Applying turbo spin echo sequences feasible for biopsy, the signal void of a 18 G needle (Cook) parallel to Gf reached between 0.3 and. 4.6 mm further into the medium than the real needle tip, depending on needle orientation relative to B0. The diameter of the signal void around the needle varied, the needle shaft was right in the centre of the signal void. With Gf orthogonal to the needle the offset of signal void to needle tip ranged from 2.7 to 3.3 mm, while the actual position of the needle shaft was up to 3.3 mm lateral of the signal void center. While nominal echo times did not influence the size of the artifact in turbo-spin-echo sequences, the artifacts increased with smaller matrix and larger water-fat shift. Material and mass of the needle determined the size of the artifacts as well. CONCLUSION: Localisation accuracy of the needle can be optimised by choosing optimal gradient directions depending on whether needle tip or shaft position should be displayed.


Asunto(s)
Artefactos , Biopsia con Aguja , Imagen por Resonancia Magnética/métodos , Agujas , Imagen por Resonancia Magnética/instrumentación , Fantasmas de Imagen
15.
Rofo ; 168(1): 77-83, 1998 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-9501938

RESUMEN

AIM: To review the complications of CT guided lumbar sympathicolysis (CTLS) on the basis of our own experience and the available literature. METHODS: 241 CTLS were performed by a standard technique according to Haaga's method. Clinical follow-up revealed 4 serious complications; these were analysed and compared with published cases. RESULTS: Amongst our patients there were three fibrotic ureter stenoses and one retroperitoneal abscess. Analysis of the serious complications described in the literature indicates that introduction of CT guided lumbar sympathicolysis has reduced the severity and frequency of complications as compared with surgical and "blind" procedures. With CTLS, no deaths due to the procedure have been reported in the literature. The results indicate that damage to the ureters can be caused by substances used for the neurolysis. CONCLUSION: Provided certain safeguards are obeyed, CTLS is a very save treatment. However damage to the ureter may follow even when the procedure was technically satisfactory. Therefore, sonographic control of the kidneys after three months is recommended.


Asunto(s)
Vértebras Lumbares , Complicaciones Posoperatorias/epidemiología , Simpatectomía/efectos adversos , Simpatectomía/métodos , Tomografía Computarizada por Rayos X , Absceso/epidemiología , Estudios de Seguimiento , Humanos , Espacio Retroperitoneal , Estudios Retrospectivos , Obstrucción Ureteral/epidemiología
16.
Rofo ; 172(11): 922-6, 2000 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-11142126

RESUMEN

PURPOSE: To estimate the accuracy of the determination of tip position of MR compatible biopsy needles based on signal voids and artifacts in MR guided biopsies. METHOD: In a nylon grid phantom an MR compatible 18G needle (E-Z-EM) was measured in a 1.0 T imager using TSE- and FFE-sequences of 20 s and 40 s duration in 34 different orientations of needle versus B0, frequency and slice selection gradient. 4 radiologists with no experience in the evaluation of signal void artifacts estimated the needle tip positions from needle tip artifacts. The readers determined the needle tip before and after a 15 minute training session based on high resolution images with explanation of size and shape of specific artifacts of biopsy needles in 12 different orthogonal or parallel orientations to B0 and frequency encoding gradient that are possible if the needle lies parallel to the slice, i.e. orthogonal to the slice selection gradient. The values obtained before and after the training session were compared to the real position of the needle tip. RESULTS: Mean distance of actual needle tip and tip position as determined from images was 1.8 +/- 2.3 mm in TSE-versus 2.5 +/- 1.2 mm in FFE-images, with the needle length overestimated. After a 15 minute training session the positioning error decreased significantly to 0.2 +/- 1.8 mm for TSE-sequences and to 1.0 +/- 1.8 mm for FFE-sequences. A higher accuracy of tip localization was obtained with TSE sequences. CONCLUSION: In MR guided biopsies using FFE- and TSE-sequences the needle position can be more accurately determined if the reader is familiar with the 12 orthogonal or parallel positions of the needle with respect to B0 and frequency encoding gradient and the corresponding artifacts.


Asunto(s)
Biopsia con Aguja/métodos , Imagen por Resonancia Magnética , Artefactos , Medios de Contraste , Gadolinio DTPA , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
Rofo ; 172(9): 764-9, 2000 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-11079090

RESUMEN

PURPOSE: Small suspicious breast lesions that are only visible at MR imaging were preoperatively marked with a hook wire under MR-guidance to allow the removal of the lesion with tissue-sparing surgery. METHOD: In all patients the suspicious lesions were marked preoperatively under MR guidance with a hook wire using a commercially available stereotactic device. Interventions were performed with MR guidance on a 1.0 T and on a 1.5 T system. RESULTS: In 19 patients 22 lesions were localized. One lesion was missed and removed in a second procedure. The mean duration for localization was 66 +/- 20 min (range 38-119 min). In two patients two lesions were localized. The mean deviation of the wire tip to the lesion was 2.0 +/- 2.6 mm. In this series, 6 of 22 lesions were malignant. The mean diameter of the lesion was 7.6 +/- 2.6 mm (range 3-14 mm). CONCLUSION: Suspicious breast lesions detectable only in MR imaging can be accurately localized with a hook wire preoperatively under MR control to remove the lesion with a tissue-saving surgery.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Imagen por Resonancia Magnética , Radiología Intervencionista , Adulto , Anciano , Biopsia , Mama/patología , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Femenino , Humanos , Mastectomía Segmentaria , Persona de Mediana Edad , Sensibilidad y Especificidad
18.
Aktuelle Traumatol ; 22(2): 57-60, 1992 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-1351342

RESUMEN

In case of failure to detect a vault fracture in fatal head injury the physician is often accused of medical negligence. The material for the study consisted of a macerated vault with fractures in different widths. In order to detect the threshold of perceptibility it underwent radiographic examination taking pictures under different projections. Our finding is that the presence or absence of a radiographic fracture depends on the width and direction of the fracture. Therefore it is impossible to detect every single linear fracture of the vault in routine skull examination. Clinical and medico-legal consequences are discussed.


Asunto(s)
Fracturas Cerradas/diagnóstico por imagen , Traumatismos Cerrados de la Cabeza/diagnóstico por imagen , Fracturas Craneales/diagnóstico por imagen , Hueso Temporal/lesiones , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Fracturas Cerradas/patología , Traumatismos Cerrados de la Cabeza/patología , Hematoma Epidural Craneal/diagnóstico por imagen , Hematoma Epidural Craneal/patología , Humanos , Masculino , Fracturas Craneales/patología , Hueso Temporal/patología , Tomografía Computarizada por Rayos X
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