RESUMEN
PURPOSE: To assess the diagnostic efficacy of multiparametric MRI using quantitative measurements of the apparent diffusion coefficient (ADC) of the liver parenchyma on diffusion-weighted imaging (DWI), signal intensity (SI) on susceptibility-weighted imaging (SWI), and gadoxetic acid-enhanced T1-weighted imaging during the hepatobiliary phase for the staging of liver fibrosis. MATERIALS AND METHODS: Seventy-seven patients underwent a 3T MRI examination, including DWI/SWI sequences and gadoxetic acid-enhanced T1-weighted MRI. Liver fibrosis according to liver biopsy was staged using the Metavir fibrosis score: F0 (n = 21, 27.3%); F1 (n = 7, 9.1%); F2 (n = 8, 10.4%); F3 (n = 12, 15.6%); and F4 (n = 29, 37.7%). SI of the liver was defined using region-of-interest measurements to calculate the ADC values, the relative enhancement (RE) in the hepatobiliary phase, and the liver-to-muscle ratio (LMR) measurements for SWI. RESULTS: The values of RE, LMR, and ADC measurements were statistically significantly different among the five fibrosis stages (p < 0.004). Combining the three parameters in a multiparametric approach, the AUC for detecting F1 stage or greater (≥ F1) was 94%, for F2 or greater (≥F2) was 95%, for F3 or greater (≥F3) was 90%, and for stage F4 was 93%. CONCLUSIONS: Multiparametric MRI is an efficient non-invasive diagnostic tool for the staging of liver fibrosis. KEY POINTS: ⢠Multiparametric MRI has high accuracy in predicting moderate or greater liver fibrosis. ⢠Relative enhancement post- gadoxetic acid is an independent predictor of liver fibrosis. ⢠Liver SWI signal intensity and ADC values enhance the diagnostic ability.
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Medios de Contraste , Gadolinio DTPA , Aumento de la Imagen , Cirrosis Hepática/patología , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Humanos , Hígado/patología , Masculino , Persona de Mediana Edad , Proyectos Piloto , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Adulto JovenRESUMEN
OBJECTIVE: To assess a radiologist's detection rate of rib fractures in trauma CT when reading curved planar reformats (CPRs) of the ribs compared to reading standard MPRs. METHODS: Two hundred and twenty trauma CTs (146 males, 74 females) were retrospectively subjected to a software algorithm to generate CPRs of the ribs. Patients were split into two equal groups. Sixteen patients were excluded due to insufficient segmentation, leaving 107 patients in group A and 97 patients in group B. Two radiologists independently evaluated group A using CPRs and group B using standard MPRs. Two different radiologists reviewed both groups with the inverse methods setting. Results were compared to a standard of reference created by two senior radiologists. RESULTS: The reference standard identified 361 rib fractures in 61 patients. Reading CPRs showed a significantly higher overall sensitivity (P < 0.001) for fracture detection than reading standard MPRs, with 80.9% (584/722) and 71.5% (516/722), respectively. Mean reading time was significantly shorter for CPRs (31.3 s) compared to standard MPRs (60.7 s; P < 0.001). CONCLUSION: Using CPRs for the detection of rib fractures accelerates the reading of trauma patient chest CTs, while offering an increased overall sensitivity compared to conventional standard MPRs. KEY POINTS: ⢠In major blunt trauma, rib fractures are diagnosed with Computed Tomography. ⢠Image processing can unfold all ribs into a single plane. ⢠Unfolded ribs can be read twice as fast as axial images. ⢠Unfolding the ribs allows a more accurate diagnosis of rib fractures.
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Fracturas de las Costillas/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Niño , Preescolar , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Lactante , Masculino , Persona de Mediana Edad , Traumatismo Múltiple/diagnóstico por imagen , Variaciones Dependientes del Observador , Estudios Retrospectivos , Costillas/diagnóstico por imagen , Costillas/lesiones , Sensibilidad y Especificidad , Traumatismos Torácicos/diagnóstico por imagen , Heridas no Penetrantes/diagnóstico por imagen , Adulto JovenRESUMEN
BACKGROUND: Gadoteric acid is a paramagnetic gadolinium macrocyclic contrast agent approved for use in MRI of cerebral and spinal lesions and for body imaging. OBJECTIVE: To investigate the safety and efficacy of gadoteric acid in children by extensively reviewing clinical and post-marketing observational studies. MATERIALS AND METHODS: Data were collected from 3,810 children (ages 3 days to 17 years) investigated in seven clinical trials of central nervous system (CNS) imaging (n = 141) and six post-marketing observational studies of CNS, musculoskeletal and whole-body MR imaging (n = 3,669). Of these, 3,569 children were 2-17 years of age and 241 were younger than 2 years. Gadoteric acid was generally administered at a dose of 0.1 mmol/kg. We evaluated image quality, lesion detection and border delineation, and the safety of gadoteric acid. We also reviewed post-marketing pharmacovigilance experience. RESULTS: Consistent with findings in adults, gadoteric acid was effective in children for improving image quality compared with T1-W unenhanced sequences, providing diagnostic improvement, and often influencing the therapeutic approach, resulting in treatment modifications. In studies assessing neurological tumors, gadoteric acid improved border delineation, internal morphology and contrast enhancement compared to unenhanced MR imaging. Gadoteric acid has a well-established safety profile. Among all studies, a total of 10 children experienced 20 adverse events, 7 of which were thought to be related to gadoteric acid. No serious adverse events were reported in any study. Post-marketing pharmacovigilance experience did not find any specific safety concern. CONCLUSION: Gadoteric acid was associated with improved lesion detection and delineation and is an effective and well-tolerated contrast agent for use in children.
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Medios de Contraste/efectos adversos , Compuestos Heterocíclicos/efectos adversos , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética , Mercadotecnía , Compuestos Organometálicos/efectos adversos , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Observacionales como Asunto , Reproducibilidad de los ResultadosRESUMEN
PURPOSE: To assess the feasiblity of magnetic resonance (MR) susceptibility-weighted (SW) imaging as a tool to evaluate liver fibrosis grades in patients with chronic liver diseases (CLD) utilizing signal intensity (SI) measurements, with histopathologic findings as the reference standard. MATERIALS AND METHODS: This retrospective study was approved by the local ethics committee. All subjects gave written informed consent. Eighty consecutive patients (mean age, 56.8 years), 60% of whom were male [n = 48] and 40% of whom were female [n = 32], with CLD due to various underlying causes and histopathologically proved liver fibrosis were included. Biopsies were evaluated for liver fibrosis and necroinflammatory activity (according to METAVIR scoring system), iron load, and steatosis. Two radiologists, blinded to the clinical data, assessed regions of interest in the liver and spinal muscle in consensus. Liver-to-muscle SI ratios were calculated and correlated to histopathologic findings and clinical data by using univariate and multivariate regression analysis. RESULTS: Liver-to-muscle SI ratio decreased in parallel with the increasing grade of liver fibrosis and correlated strongly with liver fibrosis (r = -0.81, P < .0001) and moderately with necroinflammatory activity (r = -0.52, P < .0001) and iron load (r = -0.37, P = .0002) but did not correlate with steatosis (r = -0.18, P = .11). In multiple regression analysis, liver fibrosis and iron load independently influenced SW imaging measurements, explaining 69% of the variance of liver-to-muscle SI ratio (R(2) = 0.69, P < .001). Liver-to-muscle SI ratio performed well in grading liver fibrosis, with an area under the receiver operating characteristic curve of 0.92 for scores of F2 or higher and 0.93 for score of F4 (liver cirrhosis). CONCLUSION: SW imaging is a feasible noninvasive tool to detect moderate and advanced liver fibrosis in CLD patients.
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Cirrosis Hepática/patología , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Estudios de Factibilidad , Femenino , Humanos , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Músculo Esquelético/patología , Estudios RetrospectivosRESUMEN
PURPOSE: To determine whether gadoxetic acid-enhanced magnetic resonance (MR) imaging can be used to distinguish between simple steatosis and nonalcoholic steatohepatitis (NASH) in patients with nonalcoholic fatty liver disease (NAFLD), defined according to the steatosis activity and fibrosis (SAF) scoring system, which is based on the semiquantitative scoring of steatosis activity and liver fibrosis. MATERIALS AND METHODS: The local institutional review committee approved this study and waived written informed consent. This was a retrospective study of gadoxetic acid-enhanced 3-T MR imaging performed in 81 patients with NAFLD (45 men [56%]; mean age, 56 years; range, 25-78 years). The MR images were analyzed by using the relative enhancement (the ratio of signal intensities of the liver parenchyma before and 20 minutes after intravenous administration of gadoxetic acid). Univariate and multiple regression analyses were applied to identify variables associated with relative enhancement measurements. The ability of relative enhancement to allow differentiation between simple steatosis and NASH was assessed by using area under the receiver operating characteristic (ROC) curve analysis. RESULTS: Relative enhancement negatively correlated with the degree of lobular inflammation (r = -0.59, P < .0001), ballooning (r = -0.44, P < .0001), and fibrosis (r = -0.59, P ≤ .0001), but not with steatosis (r = -0.16, P = .15). Patients with NASH had a significantly lower relative liver enhancement (0.82 ± 0.22) than those with simple steatosis (1.39 ± 0.52) (P < .001). Relative enhancement measurements performed well in the differentiation between simple steatosis and NASH, with an area under the ROC curve of 0.85 (95% confidence interval: 0.75, 0.91) (cutoff = 1.24, sensitivity = 97%, specificity = 63%). CONCLUSION: Gadoxetic acid relative enhancement was significantly lower in patients with NASH than in patients with simple steatosis, but further prospective studies are warranted.
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Medios de Contraste , Hígado Graso/diagnóstico , Gadolinio DTPA , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Biomarcadores/análisis , Biopsia , Diagnóstico Diferencial , Hígado Graso/patología , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
PURPOSE: To evaluate the diagnostic performance of gadoxetic acid-enhanced magnetic resonance (MR) imaging in the staging of liver fibrosis in patients with diffuse chronic liver diseases (CLDs) and to investigate the factors that may influence the results. MATERIALS AND METHODS: With the approval of the Hospital Ethics Committee and waiver of the informed consent requirement, data in 102 patients with histologically proven liver fibrosis (classified according to the METAVIR system) of various underlying causes were retrospectively analyzed. Patients underwent 3.0-T MR imaging with gadoxetic acid. The signal intensity of the liver was defined by using region of interest measurements before contrast material injection and in the hepatobiliary phase (20 minutes after contrast material administration), and relative enhancement was calculated. Univariate and multivariate regression analyses were applied to identify variables associated with relative enhancement measurements, and the performance of relative enhancement measurements in the staging of liver fibrosis was assessed by using area under the receiver operating characteristic curve (AUC) analysis. RESULTS: At analysis of the relationship between enhancement measurements and histologic parameters, the relative enhancement values correlated strongly with liver fibrosis stage (r = -0.65, P < .0001) and moderately with necroinflammatory activity grades (r = -0.41, P = .002) and the presence of iron load (r = -0.21, P = .05). In multivariate analysis, only liver fibrosis stage independently influenced relative enhancement values (P < .001). The measurements performed well in the staging of liver fibrosis, with an AUC of 0.81 for stages of F1 or greater, 0.82 for stages of F2 or greater, 0.85 for stages of F3 or greater, and 0.83 for stage F4. Increased aspartate aminotransferase, gammaglutamyl transpeptidase, and alkaline phosphatase levels were independent predictors of false-negative results. CONCLUSION: The presence of hepatic fibrosis can be assessed with good discrimination by using gadoxetic acid-enhanced MR imaging, but assessment can be confounded in the setting of abnormal aspartate aminotransferase, gammaglutamyl transpeptidase, and alkaline phosphatase levels.
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Cirrosis Hepática/diagnóstico , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Biopsia , Medios de Contraste , Femenino , Gadolinio DTPA , Humanos , Cirrosis Hepática/patología , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Estudios RetrospectivosRESUMEN
OBJECTIVE: To investigate whether fetal lung volume and fetal lung volume growth over gestation are different in mothers who reported smoking during pregnancy compared to non-smoking controls. METHOD: Cross-sectional retrospective study of the data of 200 consecutive singleton pregnancies that underwent magnetic resonance imaging (MRI). Fetal lung volumes of 32 fetuses of mothers who reported smoking during pregnancy were compared to 168 fetuses of non-smoking controls. RESULTS: Cases reported smoking between 2 and 30 cigarettes per day. The mean number of cigarettes per day for cases was 10.2 ± 6.1. After logarithmic transformation, lung volumes showed a linear increase with gestational age (r(2) = 0.7). Multiple regression analysis revealed a significant influence of gestational age (p < 0.0001) but not maternal smoking status (p = 1.0) on fetal lung volumes. Comparison of the relative difference between observed and predicted lung volumes for both groups by means of unpaired t-test revealed no significant influence of maternal smoking status on this variable (p = 0.9). CONCLUSIONS: Fetuses of mothers who reported smoking during pregnancy show similar lung volumes and lung volume growth in MRI compared to non-smoking controls. Our data suggest that a reduced lung volume is not responsible for the increase in respiratory symptoms associated with prenatal smoking.
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Desarrollo Fetal/efectos de los fármacos , Pulmón/efectos de los fármacos , Imagen por Resonancia Magnética/métodos , Exposición Materna/efectos adversos , Diagnóstico Prenatal/métodos , Fumar/efectos adversos , Adulto , Femenino , Desarrollo Fetal/fisiología , Edad Gestacional , Humanos , Pulmón/embriología , Pulmón/fisiología , Mediciones del Volumen Pulmonar/métodos , Masculino , EmbarazoRESUMEN
BACKGROUND: It is debated whether iso-osmolar and low-osmolar contrast media are associated with different incidences of contrast medium-induced nephropathy (CIN) in patients with renal insufficiency. OBJECTIVE: To compare the incidence of CIN in children undergoing contrast-enhanced multidetector computer tomography (MDCT) with intravenous injection of low-osmolar (iobitridol, Xenetix® 300) or an iso-osmolar (iodixanol, Visipaque® 270) iodinated contrast medium. MATERIALS AND METHODS: One hundred forty-six children with normal renal function were included in this multicenter trial and underwent contrast-enhanced MDCT. The primary endpoint was the relative change in creatinine clearance from 48 h pre- to 72 h postcontrast medium administration using a noninferiority analysis in the intent-to-treat (ITT, n = 128) and per protocol (n = 68) populations. Secondary endpoints were incidence of CIN, global image quality, diagnostic efficacy and clinical safety. RESULTS: In the ITT population, the noninferiority of iobitridol over iodixanol was demonstrated. CIN incidence was 4.8% (three cases) with iobitridol and 10.6% (seven cases) with iodixanol (not significant). No statistically significant differences were observed for the secondary endpoints. CONCLUSION: Comparable satisfactory safety profiles were confirmed for both contrast media, with no significant difference in the incidence of CIN in children with normal renal function.
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Medios de Contraste/normas , Yohexol/análogos & derivados , Riñón/diagnóstico por imagen , Ácidos Triyodobenzoicos/normas , Adolescente , Niño , Preescolar , Medios de Contraste/efectos adversos , Medios de Contraste/farmacología , Método Doble Ciego , Femenino , Humanos , Lactante , Yohexol/efectos adversos , Yohexol/farmacología , Yohexol/normas , Riñón/efectos de los fármacos , Enfermedades Renales/inducido químicamente , Enfermedades Renales/complicaciones , Enfermedades Renales/diagnóstico por imagen , Masculino , Tomografía Computarizada Multidetector , Ácidos Triyodobenzoicos/efectos adversos , Ácidos Triyodobenzoicos/farmacologíaRESUMEN
PURPOSE: To retrospectively assess the rate of detection of skull fractures at cranial computed tomography (CT) achieved with the use of curved maximum intensity projections (MIPs) compared with that achieved by reading transverse sections only. MATERIALS AND METHODS: The institutional review board approved this research and waived informed consent. A curved thin (3-mm) MIP of the skull cap and a curved thick (50-mm) MIP of the skull base were obtained from the cranial CT data in 200 consecutive patients with head trauma. Four radiologists (two residents without experience in cranial CT and two consultants) independently evaluated all cases. Each radiologist reported findings in 100 patients by using transverse sections only and findings in the other 100 patients by using the unfolded view. The radiologists were blinded to patient names, and patient and group orders were randomized. The results were compared with a standard of reference established by two experts from all prior reading results, all reconstructions, and high-spatial-resolution multiplanar reformats. Logistic regression with repeated measurements was used for statistical analysis. RESULTS: The experts found 63 fractures in 30 patients. When transverse sections only were used, the mean patient-based fracture detection rate was 43% (13 of 30) for inexperienced and 70% (21 of 30) for experienced readers; with curved MIPs, the rates were 80% (24 of 30) and 87% (26 of 30), respectively. Overall sensitivity was higher with curved MIPs (P < .001); specificity was higher with transverse sections (P < .001). CONCLUSION: Curved MIPs enable a significantly higher fracture detection rate than transverse sections. They also considerably close the experience gap in fracture detection rate between residents and experts.
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Algoritmos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Fracturas Craneales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVES: This study investigated the long-term effect of carotid endarterectomy (CEA) on cognitive brain function by means of P300 evoked potentials. METHODS: Twenty-five consecutive patients (36% women) with a median age of 68 years underwent CEA with a median degree of stenosis of 90%. Cognitive brain function was objectively measured by means of P300 auditory evoked potentials (peak latencies in milliseconds [ms]) before CEA, at discharge, and at 1 and 5 years. Values were compared with 25 age- and sex-matched healthy individuals. RESULTS: Cognitive P300 evoked potentials were prolonged (ie, impaired) in patients before CEA compared with controls (vertex [Cz], 384 +/- 52 vs 357 +/- 16 ms, P = .020]. At 1 year, P300 evoked potentials were significantly shortened (ie, improved) in patients after CEA compared with baseline values [Cz, 371 +/- 38 vs 384 +/- 52 ms, P = .010]. Furthermore, no difference between patients after CEA and controls was observed [Cz, 371 +/- 38 vs 360 +/- 14 ms, P = .21]. This effect was sustained at 5 years, and P300 evoked potentials continued to be significantly shortened (ie, improved) in patients after CEA compared with baseline values [Cz, 367 +/- 39 vs 384 +/- 52 ms, P = .040]. Continuing, no difference between patients after CEA and controls could be observed [Cz, 367 +/- 39 vs 362 +/- 17 ms, P = .58]. These results could be confirmed in repeated measures analysis of variance for Cz (P = .025) and frontal (Fz) results (P = .018). CONCLUSIONS: CEA improves previously impaired cognitive brain function as shown by P300 measurements similar to normal cognitive brain function of age- and sex-matched healthy individuals. This beneficial effect is sustained up to 5 years after treatment.
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Estenosis Carotídea/cirugía , Trastornos del Conocimiento/prevención & control , Cognición/fisiología , Endarterectomía Carotidea/métodos , Potenciales Relacionados con Evento P300 , Anciano , Anciano de 80 o más Años , Estenosis Carotídea/diagnóstico por imagen , Estudios de Casos y Controles , Trastornos del Conocimiento/diagnóstico , Endarterectomía Carotidea/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Probabilidad , Valores de Referencia , Medición de Riesgo , Factores de Tiempo , Resultado del Tratamiento , UltrasonografíaRESUMEN
OBJECTIVES: To investigate developmental changes in the apparently unaffected contralateral lung by using signal intensity ratios (SIR) and lung volumes (LV), and to search for correlation with clinical outcome. METHODS: Twenty-five fetuses (22-37 weeks' gestation) were examined. Lung/liver signal intensity ratios (LLSIR) were assessed on T1-weighted and T2-weighted sequences for both lungs, then together with LV compared with age-matched controls of 91 fetuses by using the U test. Differences in LLSIRs and lung volumes were correlated with neonatal outcomes. RESULTS: LLSIRs in fetuses with congenital diaphragmatic hernia (CDH) were significantly higher in both lungs on T1-weighted images and significantly lower on T2-weighted images, compared with normals (p < 0.05), increasing on T2-weighted imaging and decreasing on T1-weighted imaging during gestation. Total LV were significantly smaller in the CDH group than in controls (p < 0.05). No significant differences in LLSIR of the two lungs were found. Outcomes correlated significantly with total LV, but not with LLSIR. CONCLUSION: Changes in LLSIR seem to reflect developmental impairment in CDH; however, they provide no additional information in predicting outcome. LV remains the best indicator on fetal MR imaging of neonatal survival in isolated, left-sided CDH.
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Algoritmos , Hernia Diafragmática/patología , Hernias Diafragmáticas Congénitas , Interpretación de Imagen Asistida por Computador/métodos , Pulmón/patología , Imagen por Resonancia Magnética/métodos , Diagnóstico Prenatal/métodos , Femenino , Humanos , Aumento de la Imagen/métodos , Pulmón/embriología , Masculino , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Modern CT scanners provide automatic dose adjustment systems, which are promising options for reducing radiation dose in pediatric CT scans. Their impact on patient dose, however, has not been investigated sufficiently thus far. OBJECTIVE: To evaluate automated tube voltage selection (ATVS) in combination with automated tube current modulation (ATCM) in non-contrast pediatric chest CT, with regard to the diagnostic image quality. MATERIALS AND METHODS: There were 160 non-contrast pediatric chest CT scans (8.7±5.4 years) analyzed retrospectively without and with ATVS. Correlations of volume CT Dose Index (CTDIvol) and effective diameter, with and without ATVS, were compared using Fisher's z-transformation. Image quality was assessed by mean signal-difference-to-noise ratios (SDNR) in the aorta and in the left main bronchus using the independent samples t-test. Two pediatric radiologists and a general radiologist rated overall subjective Image quality. Readers' agreement was assessed using weighted kappa coefficients. A p value <0.05 was considered significant. RESULTS: CTDIvol correlation with the effective diameter was r = 0.62 without and r = 0.80 with ATVS (CI: -0.04 to -0.60; p = 0.025). Mean SDNR was 10.88 without and 10.03 with ATVS (p = 0.0089). Readers' agreement improved with ATVS (weighted kappa between pediatric radiologists from 0.1 (0.03-0.16) to 0.27 (0.09-0.45) with ATVS; between general and each pediatric radiologist from 0.1 (0.06-0.14) to 0.12 (0.05-0.20), and from 0.22 (0.11-0.34) to 0.36 (0.24-0.49)). CONCLUSION: ATVS, combined with ATCM, results in a radiation dose reduction for pediatric non-contrast chest CT without a loss of diagnostic image quality and prevents errors in manual tube voltage setting, and thus protecting larger children against an unnecessarily high radiation exposure.
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Tórax/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Niño , Medios de Contraste/metabolismo , Femenino , Humanos , Masculino , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Estudios Retrospectivos , Relación Señal-RuidoRESUMEN
BACKGROUND AND AIM OF THE STUDY: Non-occlusive mesenteric ischaemia (NOMI) is characterised by hypoperfusion of the intestines without evidence of mechanical obstruction, potentially leading to extensive ischaemia and necrosis. Low cardiac output appears to be a major risk factor. Cardiopulmonary resuscitation aims at restoring blood flow after cardiac arrest. However, post restoration of spontaneous circulation, myocardial stunning limits immediate recovery of sufficient cardiac function. Since after successful cardiopulmonary resuscitation patients are often ventilated and sedated, NOMI might be underdiagnosed and potentially life-saving treatment delayed. MATERIAL AND METHODS: A prospectively maintained multi-purpose cohort of out of hospital cardiac arrest survivors, who had successful restoration of spontaneous circulation, was used for this retrospective database analysis. Patients' charts were screened for clinical, radiological or pathological evidence of NOMI and clinical data were collected. RESULTS: Between 2000 and 2014, 1780 patients who were successfully resuscitated after out of hospital cardiac arrest were screened for NOMI. Twelve patients (0.68 %) suffered from NOMI and six of those died (50 %). Patients suffering from NOMI tended to have a longer duration until restoration of spontaneous circulation (27 vs. 20 min, p=0.128) and had significantly higher lactate (14 mmol/l vs. 8 mmol/l, p=0.002) and base deficit levels at admission (-17 vs. -10, p=0.012). Median leukocyte counts in NOMI patients peaked at the day of diagnosis. CONCLUSION: NOMI is a rare but life-threatening and potentially curable complication following successful cardiopulmonary resuscitation. Lactate and base deficit at admission could help to identify patients at risk for developing NOMI who might benefit from increased clinical attention.
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Reanimación Cardiopulmonar/efectos adversos , Isquemia Mesentérica/etiología , Paro Cardíaco Extrahospitalario/complicaciones , Sobrevivientes , Austria/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Isquemia Mesentérica/diagnóstico , Isquemia Mesentérica/epidemiología , Persona de Mediana Edad , Paro Cardíaco Extrahospitalario/terapia , Estudios Prospectivos , Factores de Riesgo , Tasa de Supervivencia/tendenciasRESUMEN
Normal fetal lung development is a complex process influenced by mechanical and many biochemical factors. In addition to ultrasound, fetal magnetic resonance imaging (MRI) constitutes a new method to investigate this process in vivo during the second and third trimester. The techniques of MRI volumetry, assessment of signal intensities, and MRI spectroscopy of the fetal lung have been used to analyze this process and have already been applied clinically to identify abnormal fetal lung growth. Particularly in conditions such as oligohydramnios and congenital diaphragmatic hernia (CDH), pulmonary hypoplasia may be the cause of neonatal death. A precise diagnosis and quantification of compromised fetal lung development may improve post- and perinatal management. The main events in fetal lung development are reviewed and MR volumetric data from 106 normal fetuses, as well as different examples of pathological lung growth, are provided.
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Feto/anomalías , Feto/embriología , Pulmón/anomalías , Pulmón/embriología , Imagen por Resonancia Magnética/métodos , Femenino , Desarrollo Fetal/fisiología , Enfermedades Fetales/diagnóstico , Madurez de los Órganos Fetales/fisiología , Humanos , Enfermedades Pulmonares/diagnóstico , Enfermedades Pulmonares/embriología , Embarazo , Diagnóstico PrenatalRESUMEN
The assessment of the urinary system is typically performed by ultrasound. Nevertheless, an ultrasound may be inconclusive in fetuses with renal diseases that result in anhydramnios or oligohydramnios. In such cases, and in other cases in which ultrasound is limited, further investigation with MR should be considered. In the following article, we will provide an overview of the most commonly encountered disorders of the urinary system and their appearance on fetal MR imaging. Fetal MR imaging can accurately diagnose a wide variety of urinary tract disorders and must be seen as a valuable complementary tool to ultrasound in the assessment of the urinary system, particularly in cases of inconclusive ultrasound findings.
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Enfermedades Fetales/diagnóstico , Imagen por Resonancia Magnética/métodos , Anomalías Urogenitales/diagnóstico , Enfermedades Urológicas/diagnóstico , Femenino , Humanos , EmbarazoRESUMEN
OBJECTIVE: To evaluate age-dependent changes in fetal kidney measurements with MRI. PATIENTS AND METHODS: Fetal MRI examinations were used to study the kidney length (218 fetuses), signal intensities of renal tissue, renal pelvis, and liver tissue on T2-weighted images (223 fetuses), and the whole-kidney apparent diffusion coefficient (107 fetuses). A 1.5 T superconducting unit with a phased array coil was used in patients from 16 to 39 weeks' gestation. The imaging protocol included T2-weighted single-shot fast spin-echo, T2-weighted balanced angiography and diffusion-weighted sequences. Slice thickness ranged from 3 to 5mm. RESULTS: Fetal kidney length as a function of gestational age was expressed by the linear regression: kidney length (mm)=0.190 x gestational age (d) -8.034 (R(2) = 0.883, p < 0.001). Paired t-test analysis showed a highly statistically significant difference between the ratio of renal tissue signal intensity to renal pelvis signal intensity and the ratio of liver signal intensity to renal pelvis signal intensity on T2-weighted images (t = -50.963, d.f. = 162, p < 0.001), with renal tissue hyperintense to liver tissue. The apparent diffusion coefficient in relation to gestational age was described by the equation: ADC (microm(2)/s) = 0.0302 x square (gestational age (d)) -14.202 x gestational age (d) +2,728.6 (R(2) = 0.225, p < 0.001). CONCLUSION: The length, signal intensity on T2-weighted images, and apparent diffusion coefficient of the fetal kidney change significantly with gestational age. The presented data may help in the prenatal diagnosis of renal anomalies.
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Riñón/embriología , Imagen por Resonancia Magnética/métodos , Femenino , Edad Gestacional , Humanos , Modelos Lineales , Valores de ReferenciaRESUMEN
Bellini duct carcinoma accounts for 1-3% of all renal carcinomas and is characterized by an aggressive course and extremely poor prognosis. Conventional treatment for renal-cell carcinoma seems to be ineffective. Since the histology of Bellini duct carcinoma is similar to urothelial carcinoma, chemotherapy for urothelial cancer might be more promising than conventional treatment. We present a patient with renal carcinoma of the left kidney who underwent laparoscopic extrafascial nephrectomy and adrenalectomy. Histopathologic work-up showed Bellini duct carcinoma (pT3a, NX, G3, R0 and M0). Eight months after surgery, disease progression was observed with local recurrence, multiple pulmonal lesions, para-aortic and aortocaval lymphadenopathies and a solitary bone lesion. First-line treatment with interferon-alpha and interleukin-2, as well as second-line treatment with thalidomide, were ineffective. Disease progressed rapidly and the patient experienced a dramatic reduction in performance status and quality of life. Six courses of chemotherapy with cisplatin and gemcitabine were given, a treatment reported to be highly active in urothelial cancer. The treatment was well tolerated, with thrombopenia WHO grade II, anemia WHO grade I and nausea/vomitus WHO grade II being the most severe side effects. Follow-up computer tomography revealed partial remission with 50-100% response at the different sites of metastasis. This response was accompanied by a dramatic improvement in performance status (from an initial 60% to 100% Karnofsky index) and quality of life. The combination of cisplatin and gemcitabine was highly active in this patient with metastatic Bellini duct carcinoma, even given as third-line treatment. This regimen fulfils all criteria for palliative treatment, as our patient showed an impressive improvement in WHO performance status and therefore in quality of life. Histopathologic characteristics should be a major criterion for treatment strategy in renal carcinoma, particularly in Bellini duct carcinoma.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/secundario , Cisplatino/administración & dosificación , Desoxicitidina/análogos & derivados , Desoxicitidina/administración & dosificación , Neoplasias Renales/tratamiento farmacológico , Cuidados Paliativos/métodos , Antineoplásicos/administración & dosificación , Carcinoma de Células Renales/cirugía , Humanos , Interferón-alfa/uso terapéutico , Interleucina-2/uso terapéutico , Neoplasias Renales/cirugía , Metástasis Linfática , Masculino , Persona de Mediana Edad , Nefrectomía , Talidomida/uso terapéutico , Insuficiencia del Tratamiento , Resultado del Tratamiento , GemcitabinaRESUMEN
RATIONALE AND OBJECTIVES: High-resolution magnetic resonance (HR-MR) images of human cervical tissue samples were correlated with low magnification histology to investigate the MR presentation of normal and pathologic anatomic structures in cervical tissue samples at 3T. METHODS: Tissue samples were obtained from five large loop excision of the transformation zone (LLETZ) cone biopsies and one surgical specimen. HR-MR images (3D-Spin Echo sequence: TR/TE: 1500/60 milliseconds, voxel size of 117 x 208 x 234 microm) and low magnification (5x) histology sections were acquired in the same anatomical planes and correlated. RESULTS: In vitro HR-MR imaging of cervical tissue samples correlated well with low magnification microscopic histology, demonstrating normal anatomy (epithelium and its mucus layer, connective tissue of the stroma, glands, blood vessels). In vitro HR-MR imaging adds information about tumor content and margins. CONCLUSIONS: High resolution MR imaging of cervical tissue samples assists in the identification of both normal structures and pathologic changes.
Asunto(s)
Cuello del Útero/patología , Imagen por Resonancia Magnética/métodos , Biopsia , Femenino , HumanosRESUMEN
Radiologic evaluation of musculoskeletal abnormalities in children is now usually performed by ultrasound and magnetic resonance imaging, owing to their excellent anatomic detail and lack of ionizing radiation. There remains a group of certain congenital and acquired conditions in which computed tomography (CT) can deliver invaluable information, and thus its application is justified in some pediatric patients. This article provides an overview of the most current imaging techniques for the latest generation of CTs, with particular emphasis on dose reduction. We also discuss the most important pathologic entities in which CT significantly contributes to the diagnostic workup or post-therapy follow-up.
Asunto(s)
Artrografía/tendencias , Huesos/diagnóstico por imagen , Enfermedades Musculoesqueléticas/diagnóstico por imagen , Traumatismos por Radiación/prevención & control , Protección Radiológica/métodos , Tomografía Computarizada por Rayos X/tendencias , Artrografía/efectos adversos , Niño , Humanos , Traumatismos por Radiación/etiología , Tomografía Computarizada por Rayos X/efectos adversosRESUMEN
Adrenal tumors include those of neural and cortical origin. Although most neuroblastomas present as abdominal masses, pheochromocytomas and cortical tumors usually present with endocrine dysfunction. Although imaging may not be able to differentiate benign lesions from malignant tumors, or whether they arise in the adrenal medulla or cortex, imaging is useful in determining the extent of the lesion and its relation to surrounding anatomic structures, particularly to vessels. Regardless of what imaging modality is used, meticulous attention to technique is required.