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1.
Clin Radiol ; 74(6): 456-466, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30905380

RESUMEN

AIM: To investigate how spectral computed tomography (SCT) values impact the staging of non-small cell lung cancer (NSCLC) patients. MATERIALS AND METHODS: One hundred and thirteen patients with confirmed NSCLC were included in a prospective cohort study. All patients underwent single-phase contrast-enhanced SCT (using the fast tube voltage switching technique, 80-140 kV). SCT values (iodine content [IC], spectral slope pitch, and radiodensity increase) of malignant tissue (primary and metastases) and lymph nodes (LNs) were measured. Adrenal masses were evaluated in a virtual non-contrast series (VNS). If pulmonary embolism was present, pulmonary perfusion was analysed as an additional finding. RESULTS: Fifty-two untreated primary NSCLC lesions were evaluable. Lung adenocarcinoma had significantly higher normalised IC (NIC: 19.37) than squamous cell carcinoma (NIC: 12.03; p=0.035). Pulmonary metastases were not significantly different from benign lung nodules. A total of 126 LNs were analysed and histologically proven metastatic LNs (2.08 mg/ml) had significantly lower IC than benign LNs (2.58 mg/ml; p=0.023). Among 34 adrenal masses, VNS identified adenomas with high sensitivity (91%) and specificity (100%). In two patients, a perfusion defect due to pulmonary embolism was detected in the iodine images. CONCLUSION: SCT may contribute to the differentiation of histological NSCLC subtypes and improve the identification of LN metastases. VNS differentiates adrenal adenoma from metastasis. In case of pulmonary embolism, iodine imaging can visualise associated pulmonary perfusion defects.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Tomografía Computarizada por Rayos X/métodos , Anciano , Estudios de Cohortes , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Masculino , Estadificación de Neoplasias , Estudios Prospectivos , Sensibilidad y Especificidad
2.
Clin Radiol ; 72(9): 754-763, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28545684

RESUMEN

AIM: To evaluate different magnetic resonance imaging (MRI) sequences for diagnosis of pulmonary manifestations of cystic fibrosis (CF) in comparison to chest computed tomography (CT), including an extended outcome analysis. MATERIALS AND METHODS: Twenty-eight patients with CF (15 male, 13 female, mean age 30.5±9.4 years) underwent CT and MRI of the lung. MRI (1.5 T) included different T2- and T1-weighted sequences: breath-hold HASTE (half Fourier acquisition single shot turbo spin echo) and VIBE (volumetric interpolated breath-hold examination, before and after contrast medium administration) sequences and respiratory-triggered PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) sequences with and without fat signal suppression, and perfusion imaging. CT and MRI images were evaluated by the modified Helbich and the Eichinger scoring systems. The clinical follow-up analysis assessed pulmonary exacerbations within 24 months. RESULTS: The highest concordance to CT was achieved for the PROPELLER sequences without fat signal suppression (concordance correlation coefficient CCC of the overall modified Helbich score 0.93 and of the overall Eichinger score 0.93). The other sequences had the following concordance: PROPELLER with fat signal suppression (CCCs 0.91 and 0.92), HASTE (CCCs 0.87 and 0.89), VIBE (CCCs 0.84 and 0.85) sequences. In the outcome analysis, the combined MRI analysis of all five sequences and a specific MRI protocol (PROPELLER without fast signal suppression, VIBE sequences, perfusion imaging) reached similar correlations to the number of pulmonary exacerbations as the CT examinations. CONCLUSION: An optimum lung MRI protocol in patients with CF consists of PROPELLER sequences without fat signal suppression, VIBE sequences, and lung perfusion analysis to enable high diagnostic efficacy and outcome prediction.


Asunto(s)
Fibrosis Quística/diagnóstico por imagen , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Medios de Contraste , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
3.
Eur Radiol ; 23(6): 1487-94, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23314597

RESUMEN

OBJECTIVES: To compare the costs of CT- and MR-guided lumbosacral nerve root infiltration for minimally invasive treatment of low back pain and radicular pain. METHODS: Ninety patients (54 men, 36 women; mean age, 45.5 ± 12.8 years) underwent MR-guided single-site periradicular lumbosacral nerve root infiltration with 40 mg of triamcinolone acetonide. A further 91 patients (48 men, 43 women; mean age, 59.1 ± 13.8 years) were treated under CT fluoroscopy guidance. Prorated costs of equipment use (purchase, depreciation and maintenance), staff costs based on involvement times and expenditure for disposables were identified for MR- and CT-guided procedures. RESULTS: Mean intervention time was 20.6 min (14-30 min) for MR-guided and 14.3 min (7-32 min) for CT-guided treatment. The average total costs per patient were €177 for MR-guided and €88 for CT-guided interventions. These consisted of (MR/CT guidance) €93/29 for equipment use, €43/35 for staff and €41/24 for disposables. CONCLUSIONS: Lumbosacral nerve root infiltration using MRI guidance is still about twice as expensive as infiltration using CT guidance. Given the advantages of no radiation exposure and possible future decrease in prices for MRI devices and MR-compatible injection needles, MR-guided nerve root infiltration may become a promising alternative to the CT-guided procedure. KEY POINTS: • MR-guided nerve root infiltration therapy is now technically and clinically established. • Costs using MRI guidance are still about double those for CT guidance. • MR guidance involves no radiation exposure to patients and personnel. • MR-guided nerve root infiltration may become a promising alternative to CT.


Asunto(s)
Fluoroscopía/economía , Dolor de la Región Lumbar/diagnóstico , Vértebras Lumbares/patología , Imagen por Resonancia Magnética/economía , Raíces Nerviosas Espinales/patología , Tomografía Computarizada por Rayos X/economía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Alemania , Costos de la Atención en Salud , Humanos , Dolor de la Región Lumbar/economía , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Raíces Nerviosas Espinales/diagnóstico por imagen , Factores de Tiempo , Adulto Joven
4.
Eur Radiol ; 22(1): 59-72, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21845461

RESUMEN

OBJECTIVES: To obtain an overview of the current clinical practice of cardiac computed tomography (CT). METHODS: A 32-item questionnaire was mailed to a total of 750 providers of cardiac CT in 57 countries. RESULTS: A total of 169 questionnaires from 38 countries were available for analysis (23%). Most CT systems used (94%, 207/221) were of the latest generation (64-row or dual-source CT). The most common indications for cardiac CT was exclusion of coronary artery disease (97%, 164/169). Most centres used beta blockade (91%, 151/166) and sublingual nitroglycerine (80%, 134/168). A median slice thickness of 0.625 mm with a 0.5-mm increment and an 18-cm reconstruction field of view was used. Interpretation was most often done using source images in orthogonal planes (92%, 155/169). Ninety percent of sites routinely evaluate extracardiac structures on a large (70%) or cardiac field of view (20%). Radiology sites were significantly more interested in jointly performing cardiac CT together with cardiology than cardiologists. The mean examination time was 18.6 ± 8.4 min, and reading took on average 28.7 ± 17.8 min. CONCLUSIONS: Cardiac CT has rapidly become established in clinical practice, and there is emerging consensus regarding indications, conduct of the acquisition, and reading.


Asunto(s)
Antagonistas Adrenérgicos beta/administración & dosificación , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Nitroglicerina/administración & dosificación , Pautas de la Práctica en Medicina , Tomografía Computarizada por Rayos X , Vasodilatadores/administración & dosificación , Cardiología , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Enfermedad de la Arteria Coronaria/epidemiología , Encuestas de Atención de la Salud , Humanos , Interpretación de Imagen Asistida por Computador , Guías de Práctica Clínica como Asunto , Dosis de Radiación , Encuestas y Cuestionarios
5.
Int J Infect Dis ; 116: 391-396, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34952210

RESUMEN

BACKGROUND AND AIMS: Chronic hepatitis B virus (HBV) infection is the main cause of hepatocellular carcinoma (HCC) in sub-Saharan Africa (SSA). An HCC screening initiative was piloted in an established cohort of individuals co-infected with human immunodeficiency virus (HIV) and HBV on antiretroviral therapy (ART) at two outpatient clinics in Lusaka, Zambia. METHODS: All patients underwent abdominal ultrasound (AUS) and transient elastography. RESULTS: Among 279 patients co-infected with HIV/HBV, 165 (59.1%) were men, median age was 34 years [interquartile range (IQR) 28-39 years] and median CD4 count was 246 cells/µL (IQR 112-355 cells/µL) at ART initiation. While 102 (55.7%) individuals had elevated transaminases, 114 (59.7%) had HBV levels >2000 IU/mL and 59 (24.6%) had significant fibrosis. At their first AUS measurement, 75 (26.9%) participants had hepatomegaly and 69 (24.7%) had periportal fibrosis. Five patients had a liver lesion >1 cm, an indication for confirmatory imaging. CONCLUSIONS: In one of the first HCC screening initiatives in SSA, 2% of patients co-infected with HIV/HBV had significant liver lesions, and one-quarter had findings suggestive of schistosomiasis-induced liver damage.


Asunto(s)
Carcinoma Hepatocelular , Coinfección , Infecciones por VIH , Hepatitis B Crónica , Hepatitis B , Neoplasias Hepáticas , Adulto , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/etiología , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Hepatitis B/complicaciones , Hepatitis B/epidemiología , Virus de la Hepatitis B , Hepatitis B Crónica/complicaciones , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/epidemiología , Masculino , Proyectos Piloto , Zambia/epidemiología
6.
J Appl Genet ; 51(2): 211-4, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20453309

RESUMEN

Nijmegen breakage syndrome (NBS), a rare autosomal recessive chromosomal instability disorder, is caused by mutations in the NBN gene. Most patients known so far are of Slavic origin and carry the major founder mutation c.657-661del5. Due to an unexpectedly high incidence of NBS patients (homozygous for the c.657-661del5 mutation) in a Northeast Bavarian region in Southeast Germany, we estimated the prevalence of this mutation in this area and compared it to another German region. We found a high carrier frequency of 1/176 for the c.657-661del5 mutation among newborns in Northeast Bavaria, while the frequency of the mutation in Berlin was 1/990. We further studied families from a Slavic population isolate, the Sorbs, in the Lusatian region in Northeast Saxony, and revealed a prevalence of the c.657-661del5 mutation of 1/34. Whereas the Slavic origin of the Sorbs has been known, we attribute the surprisingly high frequencies of c.657-661del5 mutation in Bavaria (similar to frequencies of this mutation in various Eastern European countries) to a high percentage of people of Slavic origin in Northeast Bavaria.


Asunto(s)
Proteínas de Ciclo Celular/genética , Mutación , Síndrome de Nijmegen/genética , Proteínas Nucleares/genética , Eliminación de Secuencia , Inestabilidad Cromosómica/genética , Efecto Fundador , Frecuencia de los Genes , Geografía , Alemania , Homocigoto , Linfoma/epidemiología , Linfoma/genética , Neoplasias/epidemiología , Neoplasias/genética
7.
Cardiovasc Intervent Radiol ; 43(10): 1505-1514, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32642989

RESUMEN

PURPOSE: To assess the technical feasibility of MRI/CT image fusion and completeness of ablation treatment for primary or metastatic liver lesions invisible on contrast-enhanced CT planning scans and outcome in patients treated with stereotactic microwave ablation (SMWA). MATERIALS AND METHODS: The study was approved by the local ethics committee. Patients who underwent SMWA between January 2015 and December 2018 were retrospectively analyzed. All liver lesions for which MRI/CT fusion was performed due to invisibility on pre-interventional CT planning scans were included and reassessed. The outcome measurement was successful ablation of the lesion at first follow-up imaging. RESULTS: During the study period, 236 patients underwent 312 SMWAs with ablation of 496 lesions. Twenty-four lesions in 15 patients (mean age, 62 years; range, 43-80 years) were included. Following MRI/CT image fusion, all 24 lesions could be sufficiently localized to perform SMWA. The first follow-up imaging showed complete ablation of 22 lesions. Two initially incompletely ablated lesions were hepatocellular carcinomas and were successfully re-ablated afterwards. CONCLUSION: SMWA with MRI/CT image fusion is an accurate and safe treatment option for patients with liver lesions not detectable on contrast-enhanced CT planning scans. MRI/CT image fusion may allow more patients with malignant liver lesions to benefit from local ablation treatment even if their lesions are not visible on CT planning examinations.


Asunto(s)
Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética , Ablación por Radiofrecuencia/métodos , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/cirugía , Femenino , Humanos , Imagenología Tridimensional , Hígado/patología , Hígado/cirugía , Neoplasias Hepáticas/secundario , Masculino , Microondas , Persona de Mediana Edad , Estudios Retrospectivos
8.
J Vasc Access ; 10(1): 27-32, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19340796

RESUMEN

PURPOSE: Evaluation of pain perception and patient satisfaction after implantation of a central venous port catheter system under local anesthesia. METHODS: A total of 100 consecutive patients (25 outpatients, 75 inpatients) who underwent successful implantation of a port catheter into the internal jugular vein from May through August 2007 were given an 8-item questionnaire. The extent of information about the implantation, the pain perception during implantation and the friendliness of the physician and nurse were evaluated. Furthermore, the patients were asked to assess their degree of anxiety and the pain they experienced during the intervention and to give an appraisal of whether local anesthesia was adequate. Each question was assessed on a 10-point scale (10 = very true to 1 = not at all true). In addition, the overall duration of the intervention (including patient preparation, implantation, patient aftercare, disinfection of the room) was documented. RESULTS: Patients felt highly satisfied with the way they were informed (mean score of 9.65) and considered the treating physician (9.89) and nurse (9.9) extremely friendly. Local anesthesia was rated as nearly completely adequate (9.56) and the degree of pain experienced was low (9.05; 10 = no pain). The average anxiety score was 8.56 (10 = not afraid at all). Overall satisfaction with the treatment was very high (9.62; outpatients: 9.72) and patients would recommend port catheter implantation at our department to others (9.77). The mean overall duration of the intervention was 76 min (range 40-120 min). CONCLUSION: Positive patient reactions indicate that radiologic port catheter implantation under local anesthesia is a minimally invasive intervention with high patient satisfaction that can be performed on an outpatient basis and is a valid alternative to surgical implantation.


Asunto(s)
Anestesia Local , Ansiedad/prevención & control , Cateterismo Venoso Central/instrumentación , Catéteres de Permanencia , Venas Yugulares , Dolor/prevención & control , Satisfacción del Paciente , Ansiedad/etiología , Actitud del Personal de Salud , Cateterismo Venoso Central/efectos adversos , Conocimientos, Actitudes y Práctica en Salud , Humanos , Pacientes Internos , Venas Yugulares/diagnóstico por imagen , Relaciones Enfermero-Paciente , Pacientes Ambulatorios , Dolor/etiología , Dimensión del Dolor , Educación del Paciente como Asunto , Relaciones Médico-Paciente , Radiografía Intervencional , Encuestas y Cuestionarios
9.
Curr Med Chem ; 15(14): 1407-11, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18537618

RESUMEN

Currently, growth factors which have been identified in hematopoiesis and angiogenesis are re-considered as therapeutical agents in a number of neurological diseases, mainly neurodegenerative disorders like Parkinson's Disease, amyotrophic lateral sclerosis (ALS), or cerebrovascular events such as stroke. Among these growth factors, erythropoietin (EPO) and granulocyte colony-stimulating growth factor (G-CSF) are the most prominent. With regard to neurological disease, EPO has been tested in clinical trials for potential use in stroke, schizophrenia, and addiction, G-CSF is currently under clinical investigation for stroke treatment. The major advantage of these growth factors is their well-described pharmacological behavior and their clinical use over several years. A number of mechanisms of action in the CNS have been identified that are probably important for the beneficial action of these factors in animal models of disease, the most relevant relating to neuroprotection, neuroplasticity and stem cell growth and differentiation. In this review, we will discuss the current efforts and prerequisites of novel growth factor therapies for neurodegenerative diseases with regard to their possible mechanism of action on the molecular level and their effects on brain-derived stem cell populations. Additionally, we will describe the necessities for future research before such therapies can be envisioned.


Asunto(s)
Eritropoyetina/uso terapéutico , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Animales , Eritropoyetina/química , Eritropoyetina/metabolismo , Factor Estimulante de Colonias de Granulocitos/química , Factor Estimulante de Colonias de Granulocitos/metabolismo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/química , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Humanos
10.
Genes Brain Behav ; 6(2): 128-40, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16643511

RESUMEN

Spatial learning is known to depend on protein synthesis in the hippocampus. Whereas the role of the hippocampus in spatial memory is established, the biochemical and molecular mechanisms underlying this process are poorly understood. To comprehend the complex pattern of protein expression induced by spatial learning, we analyzed alterations in the rat hippocampus proteome after 7 days of spatial learning in the Morris water maze. Forty Wistar rats were randomized into two groups. Animals of group A learned to localize a hidden platform in the water maze. Animals of group B served as controls and spent exactly the same time in the water maze as animals of group A. However, no platform was used in this test and the rats could not learn to localize the target. After the last trial, hydrophilic proteins from the hippocampus were isolated. A proteome-wide study was performed, based on two-dimensional gel electrophoresis and mass spectrometry. Compared with non-learning animals, 53 (70%) proteins were downregulated and 23 (30%) proteins were upregulated after 7 days in rats with spatial learning. The overall changes in protein expression, as quantified by the induction factor, ranged from -1.62 (downregulation to 62%) to 2.10 (upregulation by 110%) compared with controls (100%). Most identified proteins exhibit known functions in vesicle transport, cytoskeletal architecture, and metabolism as well as neurogenesis. These findings indicate that learning in the Morris water maze has a morphological correlate on the proteome level in the hippocampus.


Asunto(s)
Aprendizaje Discriminativo/fisiología , Hipocampo/metabolismo , Aprendizaje por Laberinto/fisiología , Proteínas del Tejido Nervioso/metabolismo , Animales , Regulación hacia Abajo , Perfilación de la Expresión Génica , Masculino , Proteómica , Distribución Aleatoria , Ratas , Ratas Wistar , Percepción Espacial/fisiología , Conducta Espacial/fisiología , Estadísticas no Paramétricas
11.
Radiat Oncol ; 11: 26, 2016 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-26911437

RESUMEN

PURPOSE: To analyse and compare the costs of hepatic tumor ablation with computed tomography (CT)-guided high-dose rate brachytherapy (CT-HDRBT) and CT-guided radiofrequency ablation (CT-RFA) as two alternative minimally invasive treatment options of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: An activity based process model was created determining working steps and required staff of CT-RFA and CT-HDRBT. Prorated costs of equipment use (purchase, depreciation, and maintenance), costs of staff, and expenditure for disposables were identified in a sample of 20 patients (10 treated by CT-RFA and 10 by CT-HDRBT) and compared. A sensitivity and break even analysis was performed to analyse the dependence of costs on the number of patients treated annually with both methods. RESULTS: Costs of CT-RFA were nearly stable with mean overall costs of approximately 1909 €, 1847 €, 1816 € and 1801 € per patient when treating 25, 50, 100 or 200 patients annually, as the main factor influencing the costs of this procedure was the single-use RFA probe. Mean costs of CT-HDRBT decreased significantly per patient ablation with a rising number of patients treated annually, with prorated costs of 3442 €, 1962 €, 1222 € and 852 € when treating 25, 50, 100 or 200 patients, due to low costs of single-use disposables compared to high annual fix-costs which proportionally decreased per patient with a higher number of patients treated annually. A break-even between both methods was reached when treating at least 55 patients annually. CONCLUSION: Although CT-HDRBT is a more complex procedure with more staff involved, it can be performed at lower costs per patient from the perspective of the medical provider when treating more than 55 patients compared to CT-RFA, mainly due to lower costs for disposables and a decreasing percentage of fixed costs with an increasing number of treatments.


Asunto(s)
Braquiterapia/economía , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/radioterapia , Ablación por Catéter/economía , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/radioterapia , Tomografía Computarizada por Rayos X/economía , Anciano , Braquiterapia/métodos , Carcinoma Hepatocelular/economía , Ablación por Catéter/métodos , Femenino , Costos de la Atención en Salud , Humanos , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/economía , Masculino , Persona de Mediana Edad , Oncología por Radiación/economía , Radiología Intervencionista/economía , Tomografía Computarizada por Rayos X/métodos
12.
Br J Radiol ; 88(1049): 20140602, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25710210

RESUMEN

OBJECTIVE: To evaluate the role of an ultra-low-dose dual-source CT coronary angiography (CTCA) scan with high pitch for delimiting the range of the subsequent standard CTCA scan. METHODS: 30 patients with an indication for CTCA were prospectively examined using a two-scan dual-source CTCA protocol (2.0 × 64.0 × 0.6 mm; pitch, 3.4; rotation time of 280 ms; 100 kV): Scan 1 was acquired with one-fifth of the tube current suggested by the automatic exposure control software [CareDose 4D™ (Siemens Healthcare, Erlangen, Germany) using 100 kV and 370 mAs as a reference] with the scan length from the tracheal bifurcation to the diaphragmatic border. Scan 2 was acquired with standard tube current extending with reduced scan length based on Scan 1. Nine central coronary artery segments were analysed qualitatively on both scans. RESULTS: Scan 2 (105.1 ± 10.1 mm) was significantly shorter than Scan 1 (127.0 ± 8.7 mm). Image quality scores were significantly better for Scan 2. However, in 5 of 6 (83%) patients with stenotic coronary artery disease, a stenosis was already detected in Scan 1 and in 13 of 24 (54%) patients with non-stenotic coronary arteries, a stenosis was already excluded by Scan 1. Using Scan 2 as reference, the positive- and negative-predictive value of Scan 1 was 83% (5 of 6 patients) and 100% (13 of 13 patients), respectively. CONCLUSION: An ultra-low-dose CTCA planning scan enables a reliable scan length reduction of the following standard CTCA scan and allows for correct diagnosis in a substantial proportion of patients. ADVANCES IN KNOWLEDGE: Further dose reductions are possible owing to a change in the individual patient's imaging strategy as a prior ultra-low-dose CTCA scan may already rule out the presence of a stenosis or may lead to a direct transferal to an invasive catheter procedure.


Asunto(s)
Angiografía Coronaria/métodos , Enfermedad Coronaria/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Humanos , Yohexol/análogos & derivados , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Dosis de Radiación , Protección Radiológica/métodos
13.
Brain Res ; 858(2): 338-47, 2000 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-10708685

RESUMEN

Whereas acute hyperglycemia has been shown to result in an unchanged local cerebral glucose utilization (LCGU) the changes of LCGU during chronic hyperglycemia are a matter of dispute. The present study had three aims: (1) To compare the effects of acute and chronic hyperglycemia on LCGU and to investigate in vivo the lactate level as a potential indicator of glycolytic flux. (2) To investigate local changes in brain Glut1 and/or Glut3 glucose transporter densities during chronic hyperglycemia. (3) To analyze the relationship between LCGU and local Glut densities during chronic hyperglycemia. To induce chronic hyperglycemia in rats steptozotocin was given i.p. and experiments were performed 3 weeks later. LCGU was measured by the 2-[14C]deoxyglucose method and intraparenchymal lactate concentration by MR-spectroscopy. Local densities of the glucose transport proteins were determined by immunoautoradiographic methods. During chronic hyperglycemia weighted average of LCGU increased by 13.9% whereas it remained unchanged during acute hyperglycemia. The cerebral lactate/choline ratio was increased by 143% during chronic hyperglycemia. The average density of glucose transporters Glut1 decreased by 7.5%. Local densities of Glut1 were decreased in 12 of 28 brain structures. Glut3 remained unchanged. Positive correlations were found between LCGU and local Glut densities during control conditions and during chronic hyperglycemia. It was concluded that (1) Chronic, but not acute hyperglycemia is followed by an increased LCGU. (2) The capacity to transport glucose is decreased during chronic hyperglycemia. (3) Increased LCGU and decreased densities of Glut1 are matched on a local level.


Asunto(s)
Encéfalo/metabolismo , Glucosa/metabolismo , Hiperglucemia/metabolismo , Proteínas de Transporte de Monosacáridos/metabolismo , Proteínas del Tejido Nervioso , Animales , Autorradiografía , Química Encefálica/fisiología , Circulación Cerebrovascular/fisiología , Enfermedad Crónica , Transportador de Glucosa de Tipo 1 , Transportador de Glucosa de Tipo 3 , Espectroscopía de Resonancia Magnética , Masculino , Proteínas de Transporte de Monosacáridos/análisis , Ratas , Ratas Sprague-Dawley
14.
Neurosci Lett ; 250(1): 49-52, 1998 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-9696063

RESUMEN

The question was investigated whether local changes in glucose transporter densities and transport kinetics can occur when local cerebral glucose utilization (LCGU) is decreased in some brain structures. Unilateral visual deprivation was induced by monocular enucleation in 25 rats. After 1 week, the contralateral structures of the visual system were analyzed for (1) densities of glucose transporters Glut1 and Glut3 (immunoautoradiography), (2) LCGU (2-[14C]deoxyglucose method) and (3) local rate constants (3-O[14C]methylglucose method). The ipsilateral structures served as controls. During chronic visual deprivation Glut1 and Glut3 densities, LCGU and rate constants were significantly decreased in some structures of the visual system and remained unchanged in others. These results indicate a moderate degree of downregulation of glucose transporters, LCGU and rate constants in the visual system during visual deprivation.


Asunto(s)
Encéfalo/metabolismo , Glucosa/metabolismo , Proteínas de Transporte de Monosacáridos/metabolismo , Proteínas del Tejido Nervioso , Privación Sensorial/fisiología , Animales , Transporte Biológico Activo/fisiología , Encéfalo/fisiología , Glucosa/fisiología , Transportador de Glucosa de Tipo 1 , Transportador de Glucosa de Tipo 3 , Masculino , Proteínas de Transporte de Monosacáridos/fisiología , Estimulación Luminosa/métodos , Ratas , Ratas Sprague-Dawley , Corteza Visual/metabolismo , Corteza Visual/fisiología
15.
Neurosci Lett ; 310(2-3): 101-4, 2001 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-11585577

RESUMEN

The present study addresses the question whether local glucose transport kinetics are correlated with local glucose transporter densities in the brain. In 47 brain structures the local rate constants for 3-O-[(14)C]methylglucose (3-O-MG) transport, K(1) and k(2,) were quantified, and local glucose Glut1 and Glut3 transporter densities were determined by immuno-autoradiographic methods. Statistically significant correlations were found between the rate constants for glucose transport and the transporter densities. The correlations were tighter for Glut1 than for Glut3. Inasmuch as 3-O-MG is transported by the same transporter as glucose, these results indicate that the local densities of glucose transporters determine local glucose transport rates in the brain.


Asunto(s)
3-O-Metilglucosa/farmacocinética , Encéfalo/metabolismo , Proteínas de Transporte de Monosacáridos/metabolismo , Proteínas del Tejido Nervioso , Animales , Autorradiografía , Química Encefálica/fisiología , Transportador de Glucosa de Tipo 1 , Transportador de Glucosa de Tipo 3 , Masculino , Proteínas de Transporte de Monosacáridos/análisis , Ratas , Ratas Sprague-Dawley
16.
Neurosci Lett ; 271(1): 13-6, 1999 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-10471202

RESUMEN

After 3 days of water deprivation, the following parameters were measured in rats: (i) brain water content (apparent diffusion coefficient); (ii) local cerebral glucose utilization (LCGU) ([14C]deoxyglucose method) and (iii) densities of glucose transporters Glut1 and Glut3 (immunoautoradiography). The results show that brain water content is maintained after water deprivation. Densities of glucose transporters Glut1 and Glut3 increased in parallel to increased LCGU in some of the osmoregulatory structures indicating a long-term local adaptation of glucose transporters to LCGU.


Asunto(s)
Agua Corporal/metabolismo , Encéfalo/metabolismo , Desoxiglucosa/metabolismo , Glucosa/metabolismo , Proteínas de Transporte de Monosacáridos/metabolismo , Proteínas del Tejido Nervioso , Privación de Agua/fisiología , Animales , Autorradiografía , Presión Sanguínea , Transportador de Glucosa de Tipo 1 , Transportador de Glucosa de Tipo 3 , Frecuencia Cardíaca , Imagen por Resonancia Magnética , Masculino , Especificidad de Órganos , Ratas , Ratas Sprague-Dawley , Factores de Tiempo , Tritio , Equilibrio Hidroelectrolítico
17.
Rofo ; 186(12): 1102-10, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24760427

RESUMEN

PURPOSE: Assessment of experience gained by local referring physicians with the procedure of coronary computed tomographic angiography (CCTA) in the everyday clinical routine. MATERIALS AND METHODS: A 25-item questionnaire was sent to 179 physicians, who together had referred a total of 1986 patients for CCTA. They were asked about their experience to date with CCTA, the indications for coronary imaging, and their practice in referring patients for noninvasive CCTA or invasive catheter angiography. RESULTS: 53 questionnaires (30 %) were assessable, corresponding to more than 72 % of the patients referred. Of the referring physicians who responded, 94 % saw a concrete advantage of CCTA in the treatment of patients, whereby 87 % were 'satisfied' or 'very satisfied' with the reporting. For excluding coronary heart disease (CHD) where there was a low pre-test probability of disease, the physicians considered CCTA to be superior to conventional coronary diagnosis (4.2 on a scale of 1 - 5) and vice versa for acute coronary syndrome (1.6 of 5). The main reasons for unsuitability of CCTA for CT diagnosis were claustrophobia and the absence of a sinus rhythm. The level of exposure to radiation in CCTA was estimated correctly by only 42 % of the referring physicians. 90 % of the physicians reported that their patients evaluated their coronary CT overall as 'positive' or 'neutral', while 87 % of the physicians whose patients had undergone both procedures reported that the patients had experienced CCTA as the less disagreeable of the two. CONCLUSION: CCTA is accepted by the referring physicians as an alternative imaging procedure for the exclusion of CHD and received a predominantly positive assessment from both the referring physicians and the patients.


Asunto(s)
Conducta Cooperativa , Angiografía Coronaria/métodos , Cardiopatías/diagnóstico por imagen , Comunicación Interdisciplinaria , Imagen Multimodal/métodos , Derivación y Consulta , Tomografía Computarizada por Rayos X/métodos , Síndrome Coronario Agudo/diagnóstico por imagen , Actitud del Personal de Salud , Enfermedad Coronaria/diagnóstico por imagen , Humanos , Aceptación de la Atención de Salud , Sensibilidad y Especificidad , Encuestas y Cuestionarios
18.
Rofo ; 186(6): 559-66, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24347359

RESUMEN

PURPOSE: To evaluate and compare the costs of MRI-guided and CT-guided cervical nerve root infiltration for the minimally invasive treatment of radicular neck pain. MATERIALS AND METHODS: Between September 2009 and April 2012, 22 patients (9 men, 13 women; mean age: 48.2 years) underwent MRI-guided (1.0 Tesla, Panorama HFO, Philips) single-site periradicular cervical nerve root infiltration with 40 mg triamcinolone acetonide. A further 64 patients (34 men, 30 women; mean age: 50.3 years) were treated under CT fluoroscopic guidance (Somatom Definition 64, Siemens). The mean overall costs were calculated as the sum of the prorated costs of equipment use (purchase, depreciation, maintenance, and energy costs), personnel costs and expenditure for disposables that were identified for MRI- and CT-guided procedures. Additionally, the cost of ultrasound guidance was calculated. RESULTS: The mean intervention time was 24.9 min. (range: 12 - 36 min.) for MRI-guided infiltration and 19.7 min. (range: 5 - 54 min.) for CT-guided infiltration. The average total costs per patient were EUR 240 for MRI-guided interventions and EUR 124 for CT-guided interventions. These were (MRI/CT guidance) EUR 150/60 for equipment use, EUR 46/40 for personnel, and EUR 44/25 for disposables. The mean overall cost of ultrasound guidance was EUR 76. CONCLUSION: Cervical nerve root infiltration using MRI guidance is still about twice as expensive as infiltration using CT guidance. However, since it does not involve radiation exposure for patients and personnel, MRI-guided nerve root infiltration may become a promising alternative to the CT-guided procedure, especially since a further price decrease is expected for MRI devices and MR-compatible disposables. In contrast, ultrasound remains the less expensive method for nerve root infiltration guidance.


Asunto(s)
Antiinflamatorios/administración & dosificación , Inyecciones Espinales/economía , Imagen por Resonancia Magnética Intervencional/economía , Radiculopatía/tratamiento farmacológico , Radiculopatía/economía , Radiografía Intervencional/economía , Raíces Nerviosas Espinales/efectos de los fármacos , Tomografía Computarizada por Rayos X/economía , Triamcinolona Acetonida/administración & dosificación , Adulto , Anciano , Costos y Análisis de Costo , Femenino , Fluoroscopía/economía , Alemania , Humanos , Masculino , Persona de Mediana Edad , Programas Nacionales de Salud/economía
19.
Cardiovasc Intervent Radiol ; 36(6): 1508-1513, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23456309

RESUMEN

PURPOSE: To compare the rate of reintervention and midterm changes in symptom severity (SS) and Total health-related quality of life (HRQoL) scores after uterine artery embolization (UAE) and magnetic resonance-guided high-intensity focused ultrasound (MR-g HIFU) for symptomatic uterine fibroids. METHODS: Eighty women (median age 38.3 years), equally eligible for MR-g HIFU and UAE who underwent one of both treatments between 2002 and 2009 at our institution, were included. The primary end point of the study was defined as the rate of reintervention after both therapies. The secondary outcome was defined as changes in SS and Total HRQoL scores after treatment. SS and Total HRQoL scores before treatment and at midterm follow-up (median 13.3 months) were assessed by the uterine fibroid symptom and quality-of-life questionnaire (UFS-QoL) and compared. RESULTS: The rate of reintervention was significantly lower after UAE than after MR-g HIFU (p = 0.002). After both treatments, SS and Total HRQoL scores improved significantly from baseline to follow-up (UAE: p < 0.001, p < 0.001; MR-g HIFU: p = 0.002, p < 0.001). Total HRQoL scores were significantly higher after UAE than after MR-g HIFU (p = 0.032). Changes in the SS scores did not differ significantly for both treatments (p = 0.061). CONCLUSION: UAE and MR-g HIFU significantly improved the health-related quality of life of women with symptomatic uterine fibroids. After UAE, the change in Total HRQoL score improvement was significantly better, and a significantly lower rate of reintervention was observed.


Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Leiomioma/cirugía , Imagen por Resonancia Magnética/métodos , Ultrasonografía Intervencional/métodos , Embolización de la Arteria Uterina/métodos , Neoplasias Uterinas/cirugía , Adulto , Terapia Combinada/métodos , Femenino , Humanos , Calidad de Vida , Retratamiento/estadística & datos numéricos , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Resultado del Tratamiento
20.
Rofo ; 185(4): 358-66, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23494503

RESUMEN

PURPOSE: To investigate whether changes in hemodynamics induced by Valsalva maneuver can be exploited for detecting and characterizing breast lesions by optical mammography. MATERIALS AND METHODS: 30 women underwent optical imaging of the breast using a DYNOT 232 system and performing Valsalva maneuvers prior to biopsy. Changes in light absorption due to changes in oxyhemoglobin and deoxyhemoglobin concentrations were recorded volumetrically and in a time-resolved manner. The parameters full width at half maximum (FWHM), time to ten (TTT), and peak amplitude (PA) of the reconstructed concentration time curves yielded color-coded maps of the breast which were separately evaluated by two experienced readers for detection rate, degree of visibility, and detection of additional lesions. ROC analysis was performed with the evaluation results. RESULTS: 10 patients were excluded from analysis due to artifacts or inadequately performed Valsalva maneuver. The resulting 20 patients showed a clear increase in oxygenated and deoxygenated hemoglobin concentration after the onset of the Valsalva maneuver. ROC analysis yielded AUC values (0.393 - 0.779) that did not differ from random probabilities. The highest AUC values were obtained for FWHM (AUC: 0.779, detection rates [60 - 70 %], identification of additional lesions [55 - 70 %]). PA analysis had the highest detection rate (70 - 90 %) but also the highest identification of false-positive additional lesions (80 - 90 %). The concordance rates of the two readers for malignant lesions were satisfactory (0.524 - 1.0). CONCLUSION: Our study revealed susceptibility to artifacts and a large number of false-positive additional lesions, suggesting that the evaluation of hemodynamic changes after Valsalva maneuver by optical imaging is not a promising method.


Asunto(s)
Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/diagnóstico , Hemodinámica/fisiología , Interpretación de Imagen Asistida por Computador/instrumentación , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/instrumentación , Imagenología Tridimensional/métodos , Imagen Óptica/instrumentación , Imagen Óptica/métodos , Espectroscopía Infrarroja Corta/instrumentación , Espectroscopía Infrarroja Corta/métodos , Maniobra de Valsalva/fisiología , Mama/irrigación sanguínea , Mama/patología , Neoplasias de la Mama/patología , Femenino , Hemoglobinas/metabolismo , Humanos , Oxihemoglobinas/metabolismo , Estudios Prospectivos , Sensibilidad y Especificidad
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