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1.
Am J Kidney Dis ; 75(4): 480-487, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31787341

RESUMEN

RATIONALE & OBJECTIVE: Left-sided internal jugular and all subclavian central venous catheters (CVCs) cause thoracic central vein occlusions (TCVOs) more often than right-sided internal jugular catheters. To enable right-sided CVC placement in patients with TCVO, an inside-out access (IOA) approach was established at 3 vascular access centers in Europe involving use of a novel IOA device advanced from the right femoral vein. In the current analysis, we assessed the eligibility and success rate of this IOA approach in a cohort of patients with TCVO requiring a tunneled dialysis catheter. STUDY DESIGN: Retrospective multicenter observational study. SETTING & PARTICIPANTS: 36 patients with TCVO treated in Vienna, Austria; Oxford, England; or Cologne, Germany, who required hemodialysis access between July 2016 and June 2018. EXPOSURE: Application of the IOA approach to gain vascular access. OUTCOME: The primary end point was the success rate of passing the TCVO to gain dialysis access using the IOA approach. Secondary end points were catheter patency at 3 months and procedure-related complications (early infections, bleeding, hematoma, and pericardial effusions). ANALYTICAL APPROACH: Descriptive statistics to characterize eligibility, success rate, and complications of the IOA approach. RESULTS: 36 patients with TCVO and history of multiple CVCs and arteriovenous fistulas were referred to the participating centers for vascular access. 32 (89%) patients were eligible for the IOA approach. 39 treatments were performed, with 7 patients undergoing the IOA procedure a second time more than 3 months after initial CVC placement. Dialysis access was established successfully in 38 of 39 (97%) implementations of the IOA procedure. Median intervention time was 43 minutes. No complications occurred. LIMITATIONS: No comparison to other methods to place CVCs and the observational study design. CONCLUSIONS: The IOA approach is a promising method to enable rapid access to the right jugular vein in the setting of pre-existing TCVO. Additional experience is needed to understand the generalizability of these observations.


Asunto(s)
Cateterismo Venoso Central/efectos adversos , Catéteres de Permanencia/efectos adversos , Catéteres Venosos Centrales/efectos adversos , Venas Yugulares/diagnóstico por imagen , Diálisis Renal/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Cateterismo Venoso Central/tendencias , Catéteres de Permanencia/tendencias , Catéteres Venosos Centrales/tendencias , Femenino , Humanos , Venas Yugulares/cirugía , Masculino , Persona de Mediana Edad , Diálisis Renal/tendencias , Estudios Retrospectivos , Adulto Joven
2.
Liver Int ; 38(6): 1036-1044, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29091351

RESUMEN

BACKGROUND & AIMS: Reduction in portal pressure by self-expandable polytetrafluoroethylene (ePTFE)-covered transjugular intrahepatic portosystemic shunts (TIPS) is a treatment option for refractory ascites. Data on clinical outcomes after ePTFE-TIPS vs repetitive large-volume paracentesis (LVP) plus albumin (A) administration for the treatment of patients with refractory ascites are limited. METHODS: Retrospective comparison of ePTFE-TIPS vs LVP+A in terms of (i) control of ascites, (ii) occurrence of overt hepatic encephalopathy (HE) and (iii) transplant-free survival in cirrhotic patients with refractory ascites. RESULTS: Among n = 221 patients with cirrhosis and refractory ascites, n = 140 received ePTFE-TIPS and were compared to n = 71 patients undergoing repetitive LVP+A. After ePTFE-TIPS, ascites was controlled without any further need for paracentesis in n = 76 (54%; n = 7 without and n = 69 with diuretics). The need for frequent large-volume paracentesis was significantly higher in the LVP+A group than with ePTFE-TIPS (median 0.67 (IQR: 0.23-2.63) months vs 49.5 (IQR: 5.07-102.60) months until paracentesis, log-rank P < .001). De-novo incidence of HE was similar in ePTFE-TIPS and LVP+A patients (log-rank P = .361). Implantation of ePTFE-TIPS was associated with improved 1-year survival as compared to LVP+A (65.6% vs 48.4%, log-rank P = .033). Age (odds ratio (OR):1.05; 95% confidence interval (95% CI):1.03-1.07; P < .001), serum albumin (OR: 0.95; 95% CI: 0.92-0.99; P = .013) and hepatocellular carcinoma (OR: 1.66; 95% CI: 1.06-2.58; P = .026) emerged as independent predictors of survival. CONCLUSIONS: ePTFE-TIPS results in superior control of ascites without increasing the risk for overt HE as compared to LVP+A. Although ePTFE-TIPS improved 1-year survival in cirrhotic patients with refractory ascites, its use was not independently associated with transplant-free survival.


Asunto(s)
Ascitis/terapia , Cirrosis Hepática/complicaciones , Paracentesis , Derivación Portosistémica Intrahepática Transyugular , Stents , Anciano , Albúminas/uso terapéutico , Ascitis/etiología , Ascitis/mortalidad , Austria/epidemiología , Materiales Biocompatibles Revestidos , Diuréticos/uso terapéutico , Femenino , Encefalopatía Hepática/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Politetrafluoroetileno , Modelos de Riesgos Proporcionales , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Centros de Atención Terciaria , Resultado del Tratamiento
3.
Explor Target Antitumor Ther ; 3(1): 90-96, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36046358

RESUMEN

Hilar cholangiocarcinoma is a rare primary malignancy associated with a dismal prognosis. Currently, complete extended right or left-sided hepatectomy is the primary curative therapy. Achieving a negative resection margin is associated with long-term survival and better quality of life, while post-hepatectomy liver failure (PHLF) due to insufficient liver remnant remains the most dreaded complication with a negative effect on overall survival. Precise preoperative management with sufficient future remnant liver (FRL) volume is the key to achieving good results in the treatment of bile duct carcinoma. To present a case report and a literature review for preoperative FRL optimization prior to major hepatectomies for hilar cholangiocarcinoma. Improvement of postoperative outcomes after extended liver resections in the case of hilar cholangiocarcinoma. A 62-year-old Caucasian woman with Lynch syndrome presented to our department with a hilar cholangiocarcinoma Bismuth type IIIa. The patient had an insufficient future liver volume for extended liver resection. She underwent preoperative preconditioning using a liver venous deprivation (LVD) and underwent two weeks later a right trisectorectomy without any interventional complications. Liver function remained stable postoperatively. The patient was discharged on the 20th postoperative day without major surgical post-operative complications or the need for readmission. LVD is a technically feasible, safe, and effective procedure to increase the FRL in a short period of time with low intra and post-operative complications and therefore improving the survival of patients with hilar cholangiocarcinoma.

4.
Eur Radiol ; 21(11): 2326-35, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21710266

RESUMEN

OBJECTIVE: To evaluate the accuracy of multidetector computed tomography with water filling (Hydro-MDCT) in the T-staging of patients with oesophageal cancer. MATERIALS AND METHODS: There were 131 consecutive patients who were preoperatively and prospectively examined in the prone position on arterial phase contrast-enhanced MDCT, after ingestion of 1,000-1,500 ml tap water and effervescent granules. Two readers staged the local tumour growth (T-staging) independently. They assessed tumour location, size, presence of stenosis, and morphology of the outer border of the oesophageal wall and perioesophageal fat planes on CT. CT findings were compared with histopathological results from resected specimens. Data were analyzed using the SPSS statistical package. RESULTS: Both readers obtained a high sensitivity of 95% and a high positive predictive value of 96%. Accurate local staging was achieved in 76.3% and 68.7% for readers 1 and 2, respectively. Inter-reader agreement was excellent (weighted κ value of 0.93 and un-weighted κ of 0.89). CONCLUSION: Using the hydro-technique and applying specific assessment criteria, MDCT appears to be an accurate, non-invasive diagnostic tool for local tumour staging of oesophageal cancer.


Asunto(s)
Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patología , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Técnicas Histológicas/métodos , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias/métodos , Variaciones Dependientes del Observador , Periodo Posoperatorio , Periodo Preoperatorio , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
Abdom Imaging ; 34(1): 3-18, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-17653787

RESUMEN

Multi-detector computed tomography (CT) offers new opportunities in the imaging of the gastrointestinal tract. Its ability to cover a large volume in a very short scan time, and in a single breath hold with thin collimation and isotropic voxels, allows the imaging of the entire esophagus with high-quality multiplanar reformation and 3D reconstruction. Proper distention of the esophagus and stomach (by oral administration of effervescent granules and water) and optimally timed administration of intravenous contrast material are required to detect and characterize disease. In contrast to endoscopy and double-contrast studies of the upper GI tract, CT provides information about both the esophageal wall and the extramural extent of disease. Preoperative staging of esophageal carcinoma appears to be the main indication for MDCT. In addition, MDCT allows detection of other esophageal malignancies, such as lymphoma and benign esophageal tumors, such as leiomyma. A diagnosis of rupture or fistula of the esophagus can be firmly established using MDCT. Furthermore, miscellaneous esophageal conditions, such as achalasia, esophagitis, diverticula, and varices, are incidental findings and can also be visualized with hydro-multi-detector CT. Multi-detector CT is a valuable tool for the evaluation of esophageal wall disease and serves as an adjunct to endoscopy.


Asunto(s)
Enfermedades del Esófago/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Medios de Contraste , Enfermedades del Esófago/patología , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/patología , Humanos , Imagenología Tridimensional , Estadificación de Neoplasias , Interpretación de Imagen Radiográfica Asistida por Computador
6.
Acad Radiol ; 15(7): 928-33, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18572130

RESUMEN

RATIONALE AND OBJECTIVES: We sought to evaluate the diagnostic performance of high-resolution magnetic resonance imaging (MRI) and conventional MRI of the knee on a standard-field-strength MRI system compared to arthroscopic findings in patients with suspected meniscal tears. MATERIALS AND METHODS: Forty-two patients (20 women, 22 men), referred from the department of trauma surgery, with suspected medial meniscal tears and planned arthroscopy of the knee joint were included in the study. MRI was performed on a 1.0-T MRI scanner with two different protocols: (1) conventional MRI using a circular, polarized knee coil (coil diameter: 17 cm) with a sagittal dual fast spin-echo sequence (repetition time [TR]: 2500 ms; echo time [TE]: first, shortest, second, 120 ms; turbo spin echo [TSE] factor: 12; field of view: 180 mm; matrix: 256 x 512; scan percentage: 100; slice thickness: 3 mm) or (2) high-resolution MRI with a surface dual-loop coil of the medial knee compartment (temporomandibular joint, coil diameter: 8 cm) with a sagittal dual fast spin-echo sequence (TR: 2400 ms; TE: first, shortest; second, 120 ms; TSE factor: 12; field of view: 120 mm; matrix: 512 x 512; slice thickness: 2 mm). The menisci were evaluated on the basis of an adapted score (0 = normal meniscus, 1 = intrameniscal, T2-weighted hyperintense signal, 2 = discontinuity of the surface, 3 = fragmentation). Lesions that received a score of 2 or 3 were graded as meniscal tears. The MRI results were compared to the arthroscopic reports, which represented the gold standard, and the sensitivity of both protocols in detecting a meniscal tear was determined. RESULTS: Of the 42 patients included in the study, 25 (11 women and 14 men) underwent arthroscopy and all demonstrated a meniscal tear. A meniscal tear was correctly diagnosed in 76% of cases with conventional MRI and in 88% of cases with high-resolution MRI (P = .0087). CONCLUSION: High-resolution MRI, using a surface dual-loop coil and specific sequences, which can be performed on every standard-field-strength MRI scanner, is able to significantly improve diagnostic performance for the detection of a meniscal tear of the knee joint.


Asunto(s)
Artroscopía/métodos , Traumatismos de la Rodilla/diagnóstico , Imagen por Resonancia Magnética/métodos , Lesiones de Menisco Tibial , Adolescente , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Traumatismos de la Rodilla/cirugía , Masculino , Meniscos Tibiales/cirugía , Persona de Mediana Edad , Sensibilidad y Especificidad
7.
ASAIO J ; 64(1): e3-e7, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28195884

RESUMEN

Left ventricular assist device outflow graft stenosis is a rare but life-threatening complication of mechanical cirulatory support therapy. Current treatment modalities (pump exchange or systemic thrombolytic therapy) are associated with significant mortality and morbidity. Implantation of bare metal stents within the stenosed outflow graft is an alternative. Herein, we describe a series of three cases with successful stent placement. This seems to be safe and successful; however, correct and early diagnosis of outflow stenosis can be challenging. Information provided by the HeartWare ventricular assist device (HVAD) logfiles is extremely helpful for diagnosis.


Asunto(s)
Corazón Auxiliar/efectos adversos , Stents , Constricción Patológica/cirugía , Humanos , Masculino , Metales , Persona de Mediana Edad , Estudios Retrospectivos , Trasplantes
8.
Top Magn Reson Imaging ; 18(6): 445-55, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18303402

RESUMEN

The histological structure of the liver is complex, consisting of hepatocytes, biliary epithelium, and mesenchymal cells. From this large variety of cells, a broad spectrum of benign and malignant liver lesions in originate. An accurate diagnosis of these lesions is mandatory for choosing an appropriate therapeutic approach. With the recent developments in hardware and software, magnetic resonance imaging (MRI) has emerged as the method of choice in the diagnostic workup of focal liver lesions, in particular in the pretherapeutic stage. The introduction of high-field MRI at 3.0 T in the routine workup and the selective use of liver-specific contrast agents, including hepatobiliary and reticuloendothelial agents, have also strengthened the role of MRI in liver imaging. In this overview article, we will review the recent developments in 3.0-T MRI and MRI contrast agents in the diagnostic workup of the most common malignant liver tumors.


Asunto(s)
Neoplasias Hepáticas/diagnóstico , Imagen por Resonancia Magnética/métodos , Medios de Contraste , Humanos , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/patología , Metástasis de la Neoplasia/diagnóstico , Estadificación de Neoplasias
9.
JACC Cardiovasc Interv ; 9(13): 1386-92, 2016 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-27388828

RESUMEN

OBJECTIVES: The hypothesis that paclitaxel-eluting balloon angioplasty provides higher 1-year patency rates in femoropopliteal artery in-stent restenosis compared with standard percutaneous transluminal angioplasty (PTA) was tested. BACKGROUND: Several trials have demonstrated that paclitaxel-eluting balloon angioplasty reduces late luminal loss in comparison with PTA. METHOD: In a prospective, randomized, single-blind, dual-center study, 74 patients with symptomatic peripheral artery disease due to in-stent restenosis were treated with either paclitaxel-based drug-eluting balloon (DEB) angioplasty (n = 35) or standard PTA (n = 39). Clinical outcomes and patency rates were assessed at 1, 6, and 12 months. RESULTS: The mean lesion length was 17.3 ± 11.3 cm in the DEB group and 18.4 ± 8.8 cm in the PTA group. A single major complication (bleeding) was observed once (1.4%). The mean ankle-brachial index before endovascular treatment was 0.65 ± 0.16 in both groups and 0.79 ± 0.2 versus 0.84 ± 0.3 (p = 0.70, Student t test) in the DEB versus PTA group at 12 months. The 12-month primary patency rates were 40.7% (95% confidence interval [CI]: 0.26 to 0.64) versus 13.4% (95% CI: 0.05 to 0.36) (log-rank p = 0.02) in the DEB versus PTA group. The odds ratio for PTA over DEB angioplasty for experiencing an event was estimated at 2.8 (95% CI: 1.2 to 6.6). Freedom from clinically driven target lesion revascularization was 49.0% (95% CI: 0.32 to 0.75) versus 22.1% (95% CI: 0.10 to 0.48) (log-rank p = 0.11) in the DEB versus PTA group. Clinical improvement by ≥1 Rutherford-Becker category was 68.8% versus 54.5% (p = 0.87) in the DEB versus PTA group at 12 months. CONCLUSIONS: When treating peripheral artery disease in patients with in-stent restenosis in the femoropopliteal artery, paclitaxel-eluting balloon angioplasty provides significantly higher patency rates than standard PTA. (Paclitaxel Balloon Versus Standard Balloon in In-Stent Restenoses of the Superficial Femoral Artery [PACUBA I Trial] [PACUBA 1]; NCT01247402).


Asunto(s)
Angioplastia de Balón/instrumentación , Fármacos Cardiovasculares/administración & dosificación , Materiales Biocompatibles Revestidos , Arteria Femoral , Paclitaxel/administración & dosificación , Enfermedad Arterial Periférica/terapia , Arteria Poplítea , Stents , Dispositivos de Acceso Vascular , Anciano , Angioplastia de Balón/efectos adversos , Índice Tobillo Braquial , Austria , Fármacos Cardiovasculares/efectos adversos , Diseño de Equipo , Femenino , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/fisiopatología , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Paclitaxel/efectos adversos , Enfermedad Arterial Periférica/diagnóstico por imagen , Enfermedad Arterial Periférica/fisiopatología , Arteria Poplítea/diagnóstico por imagen , Arteria Poplítea/fisiopatología , Estudios Prospectivos , Recurrencia , Retratamiento , Factores de Riesgo , Método Simple Ciego , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción Vascular
10.
Eur J Radiol ; 53(3): 489-94, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15741024

RESUMEN

PURPOSE: To analyze the capabilities of chest roentgenogram (CXR) and computed tomography (CT) in the evaluation of pulmonary infectious disease in the late period (>100 days) after allogeneic bone marrow transplantation (BMT). METHODS: Ninety-four matched CXR and CT examinations were performed for clinical suspicion of infectious lung disease. The time gap between CXR and CT was 48 h at maximum. The image pairs were correlated with the patients' clinical course and with the results of diagnostic bronchoalveolar lavage (BAL). An unremarkable clinical course over the subsequent seven days after imaging and/or negative microbiological culture served as the basis for excluding infectious lung disease. Positive microbiological culture and/or improvement of symptoms after antibiotic therapy were considered as evidence of infectious disease. RESULTS: The correlation with the clinical course and/or BAL revealed a significantly higher sensitivity, negative predictive value, and accuracy for CT than for CXR (89% versus 58%, P < 0.0001; 78% versus 47%, P < 0.0001; 90% versus 68%, P < 0.0001, respectively). CT was significantly more diagnostic in BAL verified fungal and bacterial infections (P < 0.05). CONCLUSION: CT is significantly superior to CXR in the evaluation of infectious pulmonary disease in the late phase after BMT. Therefore, an unremarkable CXR should be followed by a CT scan to reliably detect or to accurately exclude early pulmonary infection in these patients.


Asunto(s)
Trasplante de Médula Ósea/efectos adversos , Enfermedades Pulmonares/diagnóstico por imagen , Enfermedades Pulmonares/microbiología , Radiografía Torácica , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Lavado Broncoalveolar , Femenino , Humanos , Enfermedades Pulmonares/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
12.
Eur J Radiol ; 70(3): 579-88, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18384995

RESUMEN

OBJECTIVES: To compare iomeprol 400 and iodixanol 320 in pulmonary artery MDCTA in subjects with suspected pulmonary embolism. METHODS: Eighty randomized subjects received equi-iodine intravenous doses (48 g) of iomeprol 400 (n=40) or iodixanol 320 (n=40), via power injector at 4 mL/s. Four-row (35 subjects) and 64-row (45 subjects) scanners were used. Lumen attenuation was determined on-site and by two off-site blinded readers in the main, lobar, segmental and subsegmental pulmonary arteries. Statistical comparison between groups was performed for demographics and lumen attenuation. RESULTS: There were no between-group differences (p>0.05) in demographics. Pulmonary artery attenuation was significantly (p

Asunto(s)
Angiografía/métodos , Yopamidol/análogos & derivados , Embolia Pulmonar/diagnóstico por imagen , Intensificación de Imagen Radiográfica/métodos , Tomografía Computarizada por Rayos X/métodos , Ácidos Triyodobenzoicos , Anciano , Medios de Contraste/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Yopamidol/administración & dosificación , Masculino , Arteria Pulmonar/diagnóstico por imagen , Sensibilidad y Especificidad , Ácidos Triyodobenzoicos/administración & dosificación
13.
Eur J Radiol ; 68(3): 493-8, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19189427

RESUMEN

OBJECTIVE: To evaluate whether diffusion-weighted imaging (DWI) is a reliable technique to quantify microstructural differences between head and neck squamous cell carcinomas (SCC) and tumour-free soft tissue. MATERIALS AND METHODS: DWI was obtained from 20 patients with histologically proven, untreated head and neck SCC. DWI was acquired using a diffusion-weighted, navigated echo-planar imaging sequence with a maximum b-value of 800 s/mm2. For an objective assessment of image quality, the signal-to-noise ratio (SNR) was calculated. Microstructural differences between vital tumour tissue and tumour-free soft tissue were quantified by calculating the apparent-diffusion-coefficients (ADC) on a pixel by pixel method. RESULTS: Echo-planar DWI provided good image quality in all patients (mean SNR 18.4). The mean ADC of SCC, (0.64+/-0.28 x 10(-3) mm2/s), was significantly (P<0.0001) lower than that of the tumour-free soft tissue, (2.51+/-0.82 x 10(-3) mm2/s). CONCLUSION: DWI is a reliable diagnostic tool to quantify the microstructural differences between vital tumour tissue and tumour-free soft tissue in patients with head and neck SCC.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Imagen de Difusión por Resonancia Magnética/métodos , Neoplasias de Cabeza y Cuello/diagnóstico , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
14.
AJR Am J Roentgenol ; 186(1): 38-43, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16357374

RESUMEN

OBJECTIVE: The purpose of our study was to compare the image quality of a wet laser printer with that of a paper printer for full-field digital mammography (FFDM). MATERIALS AND METHODS: For both a wet laser printer and a paper printer connected to an FFDM system, image quality parameters were evaluated using a standardized printer test image (luminance density, dynamic range). The detectability of standardized objects on a phantom was also evaluated. Furthermore, 640 mammograms of 80 patients with different breast tissue composition patterns were imaged with both printers. Subjective image quality parameters (brightness, contrast, and detection of details of anatomic structures-that is, skin, subcutis, musculature, glandular tissue, and fat), the detectability of breast lesions (mass, calcifications), and the diagnostic performance according to the BI-RADS classification were evaluated. RESULTS: Both the luminance density and the dynamic range were superior for the wet laser printer. More standardized objects were visible on the phantom imaged with the wet laser printer than with the paper printer (13/16 vs 11/16). Each subjective image quality parameter of the mammograms from the wet laser printer was rated superior to those of the paper printer. Significantly more breast lesions were detected on the wet laser printer images than on the paper printer images (masses, 13 vs 10; calcifications, 65 vs 48; p < 0.05). With the paper printer images, BI-RADS 4 and 5 categories were underestimated for 10 (43.5%) of 23 patients. CONCLUSION: For FFDM, images obtained from a wet laser printer show superior objective and subjective image quality compared with a paper printer. As a consequence, the paper printer should not be used for FFDM.


Asunto(s)
Periféricos de Computador , Rayos Láser , Mamografía , Intensificación de Imagen Radiográfica/instrumentación , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Fantasmas de Imagen , Sensibilidad y Especificidad , Estadísticas no Paramétricas , Pantallas Intensificadoras de Rayos X
15.
Radiology ; 241(2): 367-77, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17057065

RESUMEN

PURPOSE: To prospectively assess the accuracy of nonenhanced versus ultrasmall superparamagnetic iron oxide (USPIO)-enhanced magnetic resonance (MR) imaging for depiction of axillary lymph node metastases in patients with breast carcinoma, with histopathologic findings as reference standard. MATERIALS AND METHODS: The study was approved by the university ethics committee; written informed consent was obtained. Twenty-two women (mean age, 60 years; range, 40-79 years) with breast carcinomas underwent nonenhanced and USPIO-enhanced (2.6 mg of iron per kilogram of body weight intravenously administered) transverse T1-weighted and transverse and sagittal T2-weighted and T2*-weighted MR imaging in adducted and elevated arm positions. Two experienced radiologists, blinded to the histopathologic findings, analyzed images of axillary lymph nodes with regard to size, morphologic features, and USPIO uptake. A third independent radiologist served as a tiebreaker if consensus between two readers could not be reached. Visual and quantitative analyses of MR images were performed. Sensitivity, specificity, and accuracy values were calculated. To assess the effect of USPIO after administration, signal-to-noise ratio (SNR) changes were statistically analyzed with repeated-measurements analysis of variance (mixed model) for MR sequences. RESULTS: At nonenhanced MR imaging, of 133 lymph nodes, six were rated as true-positive, 99 as true-negative, 23 as false-positive, and five as false-negative. At USPIO-enhanced MR imaging, 11 lymph nodes were rated as true-positive, 120 as true-negative, two as false-positive, and none as false-negative. In two metastatic lymph nodes in two patients with more than one metastatic lymph node, a consensus was not reached. USPIO-enhanced MR imaging revealed a node-by-node sensitivity, specificity, and accuracy of 100%, 98%, and 98%, respectively. At USPIO-enhanced MR imaging, no metastatic lymph nodes were missed on a patient-by-patient basis. Significant interactions indicating differences in the decrease of SNR values for metastatic and nonmetastatic lymph nodes were found for all sequences (P < .001 to P = .022). CONCLUSION: USPIO-enhanced MR imaging appears valuable for assessment of axillary lymph node metastases in patients with breast carcinomas and is superior to nonenhanced MR imaging.


Asunto(s)
Neoplasias de la Mama/patología , Hierro , Ganglios Linfáticos/patología , Imagen por Resonancia Magnética/métodos , Óxidos , Adulto , Anciano , Axila , Neoplasias de la Mama/cirugía , Medios de Contraste , Dextranos , Femenino , Óxido Ferrosoférrico , Humanos , Ganglios Linfáticos/cirugía , Metástasis Linfática , Nanopartículas de Magnetita , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Sensibilidad y Especificidad
16.
Eur Radiol ; 14(8): 1465-71, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15067426

RESUMEN

The aim of this study was to evaluate the value of multidetector CT (MD-CT) with low-dose protocols in the diagnosis of acute appendicitis in a rabbit model. Ten New Zealand white rabbits underwent ligation of the appendix. MD-CT (Siemens Somatom Plus 4 Volume Zoom) was performed using three low-dose protocols: 80 kV/70 mAs; 80 kV/50 mAs; and 80 kV/20 mAs. Axial and coronal reformations were performed. Three experienced radiologists evaluated the images using a four-grade score: (1) excellent; (2) good; (3) moderate; and (4) not sufficient. Diagnosis was confirmed histopathologically. The overall score for the 80 kV/70 mAs was 1, for the 80 kV/50 mAs protocol 1.3, and the 80 kV/20 mAs protocol reached an overall score of 2. The coronal reformations reached with 1.1 (80 kV/70 mAs), 1.2 (80 kV/50 mAs), and 1.4 (80 kV/20 mAs) had a slightly better median score than the axial reconstructions. In cases of inconclusive ultrasound and clinical presentation, the use of MD-CT can be considered when evaluating children for suspected appendicitis.


Asunto(s)
Apendicitis/diagnóstico , Apéndice/diagnóstico por imagen , Yohexol/análogos & derivados , Tomografía Computarizada por Rayos X/métodos , Enfermedad Aguda , Algoritmos , Animales , Apendicitis/diagnóstico por imagen , Apéndice/cirugía , Medios de Contraste/administración & dosificación , Modelos Animales de Enfermedad , Femenino , Masculino , Variaciones Dependientes del Observador , Conejos , Dosis de Radiación , Reproducibilidad de los Resultados
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