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Pain in general and back pain in particular are associated with a variety of pathological, clinical, and sociocultural factors. There are numerous clinical and therapeutic treatment as well as imaging-options available and comprehensive knowledge is required to meet the individual clinical needs of those affected. This requires a high degree of interdisciplinary cooperation. In addition, back pain is covered differently by various numbers of insurance companies. Imaging methods, including the example of periradicular image-assisted interventions, are presented with regard to their indication and efficiency. The existing guidelines and evaluation recommendations with different structural and targeted approaches are discussed in addition to extensive legal aspects in the literature. In addition, the structured reports and the certificated curricula of the AG Bildgebende Verfahren des Bewegungsapparates (Working Group "Imaging Procedures of the Musculoskeletal System") of the Deutsche Röntgengesellschaft ("German Society of Radiology") are recommended for the quality assurance.
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Dolor de Espalda , Dolor de Espalda/diagnóstico por imagen , Dolor de Espalda/terapia , Humanos , Guías de Práctica Clínica como AsuntoRESUMEN
BACKGROUND: Cartilage imaging of small joints is increasingly of interest, as early detection of cartilage damage may be relevant regarding individualized surgical therapies and long-term outcomes. PURPOSE: The aim of this review is to explain modern cartilage imaging of small joints with emphasis on MRI and to discuss the role of methods such as CT arthrography as well as compositional and high-field MRI. MATERIALS AND METHODS: A PubMed literature search was performed for the years 2008-2018. RESULTS: Clinically relevant cartilage imaging to detect chondral damage in small joints remains challenging. Conventional MRI at 3â¯T can still be considered as a reference for cartilage imaging in clinical routine. In terms of sensitivity, MR arthrography (MR-A) and computed tomography arthrography (CT-A) are superior to non-arthrographic MRI at 1.5â¯T in the detection of chondral damage. Advanced degenerative changes of the fingers and toes are usually sufficiently characterized by conventional radiography. MRI at field strengths of 3 T and ultrahigh-field imaging at 7 T can provide additional quantifiable, functional and metabolic information. CONCLUSION: Standardized cartilage imaging plays an important role in clinical diagnostics in the ankle joint due to the availability of different and individualized therapeutic concepts. In contrast, cartilage imaging of other small joints as commonly performed in clinical studies has not yet become standard of care in daily clinical routine. Although individual study results are promising, additional studies with large patient collectives are needed to validate these techniques. With rapid development of new treatment concepts radiological diagnostics will play a more significant role in the diagnosis of cartilage lesions of small joints.
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Enfermedades de los Cartílagos , Cartílago Articular , Artrografía , Humanos , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Pigmented villonodular synovitis (PVNS) describes a rare disease caused by an abnormal proliferation of the synovial membrane in large and small joints. In order to achieve an optimal result of treatment it is necessary to carry out specific diagnostics and a targeted therapy approach. OBJECTIVE: This article gives a review of the epidemiology, etiopathogenesis and diagnostic management of PVNS as well as presenting the current therapy and treatment recommendations. MATERIAL AND METHODS: A systematic search of the literature was performed in the databank of the National Center for Biotechnology Information ( http://www.ncbi.nlm.nih.gov/pubmed ). The search targeted randomized clinical and experimental studies, systematic and non-systematic review articles, expert opinions and case reports related to PVNS, independent of the level of evidence attained by each study. RESULTS: The differential diagnosis of PVNS should be considered in cases of recurrent hemorrhagic joint effusions. The cause of the disease has not yet been exactly clarified. The final diagnosis can ultimately only be confirmed by histological investigations. In order to obtain representative histological tissue samples for the diagnosis, magnetic resonance imaging (MRI) with the appropriate heme sequences should be carried out prior to taking samples. The management of PVNS is often difficult due to the high risk of recurrence depending on the various forms. In view of the high rate of recurrence, therapy should include a complete synovectomy. CONCLUSION: For the surgical approach arthroscopic and open procedures have been described, which are currently controversially discussed with respect to the complication and recurrence rates. Adjuvant interventional therapy forms, such as radiosynoviorthesis are recommended to reduce the recurrence rate.
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Artroscopía/métodos , Biopsia/métodos , Imagen por Resonancia Magnética/métodos , Evaluación de Síntomas/métodos , Sinovitis Pigmentada Vellonodular/diagnóstico , Sinovitis Pigmentada Vellonodular/terapia , Terapia Combinada/métodos , Diagnóstico Diferencial , Edema , Humanos , Inmunosupresores/uso terapéutico , Prevalencia , Radioterapia/métodos , Enfermedades Raras/diagnóstico , Enfermedades Raras/epidemiología , Enfermedades Raras/terapia , Sinovitis Pigmentada Vellonodular/epidemiologíaRESUMEN
OBJECTIVE: The aim of this study was to investigate, using T2-mapping, the impact of functional instability in the ankle joint on the development of early cartilage damage. METHODS: Ethical approval for this study was provided. Thirty-six volunteers from the university sports program were divided into three groups according to their ankle status: functional ankle instability (FAI, initial ankle sprain with residual instability); ankle sprain Copers (initial sprain, without residual instability); and controls (without a history of ankle injuries). Quantitative T2-mapping magnetic resonance imaging (MRI) was performed at the beginning ('early-unloading') and at the end ('late-unloading') of the MR-examination, with a mean time span of 27 min. Zonal region-of-interest T2-mapping was performed on the talar and tibial cartilage in the deep and superficial layers. The inter-group comparisons of T2-values were analyzed using paired and unpaired t-tests. Statistical analysis of variance was performed. RESULTS: T2-values showed significant to highly significant differences in 11 of 12 regions throughout the groups. In early-unloading, the FAI-group showed a significant increase in quantitative T2-values in the medial, talar regions (P = 0.008, P = 0.027), whereas the Coper-group showed this enhancement in the central-lateral regions (P = 0.05). Especially the comparison of early-loading to late-unloading values revealed significantly decreasing T2-values over time laterally and significantly increasing T2-values medially in the FAI-group, which were not present in the Coper- or control-group. CONCLUSION: Functional instability causes unbalanced loading in the ankle joint, resulting in cartilage alterations as assessed by quantitative T2-mapping. This approach can visualize and localize early cartilage abnormalities, possibly enabling specific treatment options to prevent osteoarthritis in young athletes.
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Traumatismos del Tobillo/patología , Articulación del Tobillo/patología , Enfermedades de los Cartílagos/patología , Cartílago Articular/patología , Inestabilidad de la Articulación/patología , Osteoartritis/patología , Adulto , Atletas , Enfermedades de los Cartílagos/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Inestabilidad de la Articulación/epidemiología , Imagen por Resonancia Magnética , Masculino , Osteoartritis/epidemiología , Factores de Riesgo , Esguinces y Distensiones/epidemiología , Esguinces y Distensiones/patología , Adulto JovenRESUMEN
Diffusion-weighted imaging (DWI) of the breast provides additional contrast information in breast magnetic resonance imaging (MRI). The DWI procedure can easily be implemented in the routine breast MRI protocol with little time expenditure regarding image acquisition and evaluation. Evaluation of the DW images can be performed with or without the routine breast MRI sequences (T2w and T1w with contrast material) but evaluation in combination with the routine program is highly recommended. Objective analysis of the tissue diffusion can be achieved by calculating the apparent diffusion coefficient (ADC) value with the scanner software. The choice of the DW sequence, evaluation and determination of the ADC threshold to differentiate between benign and malignant lesions should be scanner adapted. The use of DW imaging qualifies for routine use regarding the differentiation between malignant and benign breast lesions. Non-mass-like lesions and monitoring neoadjuvant chemotherapy can also be evaluated with DW sequences. The benefit of the additional information from DW-MR mammography to characterize non-mass-like lesions and in the course of neoadjuvant chemotherapy remains unclear to date.
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Algoritmos , Neoplasias de la Mama/patología , Mama/patología , Imagen de Difusión por Resonancia Magnética/métodos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Femenino , Humanos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
PURPOSE: The goal of this study was to assess the informative value of contrast-enhanced ultrasound after radiofrequency ablation (RFA). Patients who had undergone RFA of malignant liver tumors were followed up with contrast-enhanced sonography (CEUS), computed tomography (CT) and/or magnetic resonance tomography (MRI), and the outcomes were compared. MATERIALS AND METHODS: 76 patients undergoing 194 RFAs for 118 hepatic neoplasms (n = 55 HCC, n = 63 metastases) in the course of a 7-year period were examined post-interventionally using CEUS and CT or MRI. During follow-up (gold standard of evaluation), contrast agent rim accumulations with a diameter greater than 5 mm and a growth rate of at least 25 % were counted as a recurrence. RESULTS: CEUS-CT comparison group: A total of 65 scan pairs were compared. In 54 cases (83.1 %) the findings were the same with either method. In 7 cases (10.8 %) CEUS confirmed the correct diagnosis, and in 2 cases (3.1 %) only CT was correct. In 2 cases (3.1 %) both methods yielded incorrect results. Diagnostic accuracy (DA): CEUS 93.8 %, CT 86.2 %. CEUS-MRI comparison group: In 23 cases (88.5 %) of a total of 26 scan pairs, the findings were the same for both CEUS and MRI. In 3 discordant cases only CEUS confirmed the correct diagnosis (3 cases, 11.5 %). Diagnostic accuracy DA (n = 26): CEUS 100 %, MRI 88.4 %. CONCLUSION: CEUS performs equally to CT and MRI in the follow-up of patients treated for liver tumors by RFA.
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Carcinoma Hepatocelular/cirugía , Ablación por Catéter/métodos , Medios de Contraste/administración & dosificación , Procesamiento de Imagen Asistido por Computador , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Imagen por Resonancia Magnética , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Fosfolípidos , Complicaciones Posoperatorias/diagnóstico , Hexafluoruro de Azufre , Tomografía Computarizada por Rayos X , Ultrasonografía Intervencional , Ultrasonografía , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Hígado/patología , Hígado/cirugía , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Neoplasia Residual/diagnóstico , Neovascularización Patológica/diagnóstico , Neovascularización Patológica/cirugía , Sensibilidad y Especificidad , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: The high diagnostic value of DWI for cholesteatoma diagnostics is undisputed. This study compares the diagnostic value of readout-segmented echo-planar DWI and single-shot TSE DWI for cholesteatoma diagnostics. MATERIALS AND METHODS: Thirty patients with newly suspected cholesteatoma were examined with a dedicated protocol, including readout-segmented echo-planar DWI and single-shot TSE DWI at 1.5T. Acquisition parameters of both diffusion-weighted sequences were as follows: b=1000 s/mm,2 axial and coronal section orientations, and section thickness of 3 mm. Image quality was evaluated by 2 readers on a 5-point Likert scale with respect to lesion conspicuity, the presence of susceptibility artifacts mimicking cholesteatomas, and overall subjective image quality. Sensitivity and specificity were calculated using histology results as the gold standard. RESULTS: Twenty-five cases of histologically confirmed cholesteatomas were included in the study group. Lesion conspicuity was higher and fewer artifacts were found when using TSE DWI (both P < .001). The overall subjective image quality, however, was better with readout-segmented DWI. For TSE DWI, the sensitivity for readers 1 and 2 was 92% (95% CI, 74%-99%) and 88% (95% CI, 69%-97%), respectively, while the specificity for both readers was 80% (95% CI, 28%-99%). For readout-segmented DWI, the sensitivity for readers 1 and 2 was 76% (95% CI, 55%-91%) and 68% (95% CI, 46%-85%), while the specificity for both readers was 60% (95% CI, 15%-95%). CONCLUSIONS: The use of TSE DWI is advisable for cholesteatoma diagnostics and preferable over readout-segmented DWI.
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Colesteatoma , Imagen Eco-Planar , Artefactos , Imagen de Difusión por Resonancia Magnética , Humanos , Aumento de la ImagenRESUMEN
Contrast-enhanced ultrasound (CEUS) has significantly improved the differentiation of hepatic lesions and the detection of liver metastases. Metastases are usually represented as hypoenhanced areas in the late phase and must then be confirmed histologically. Other lesions presenting hypoenhancement in the late phase are abscesses, hepatocellular and cholangiocellular carcinomas, adenomas, avascular necrosis, haematomas and rarely inflammatory masses. The differentiation between these relies on the patient's history, the number of lesions presenting, the B-image morphology and the enhancement pattern in the early phase of CEUS. We report the case of a 49-year-old woman with a in CT assumed pancreatic tumour in whom liver metastases were suspected and investigated by CEUS. In the late phase of this examination hypoenhanced hepatic lesions were observed, prompting us to perform a needle biopsy. The histopathological work-up surprisingly identified the hepatic lesions to be eosinophilic infiltration. After a spontaneous remission we concluded an allergic reaction to a fluoroquinolone.
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Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico por imagen , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Eosinofilia/inducido químicamente , Eosinofilia/diagnóstico por imagen , Fluoroquinolonas/efectos adversos , Enfermedades Pancreáticas/inducido químicamente , Enfermedades Pancreáticas/diagnóstico por imagen , Carcinoma/diagnóstico , Carcinoma/secundario , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundario , Persona de Mediana Edad , Neoplasias Pancreáticas/diagnóstico , UltrasonografíaRESUMEN
BACKGROUND: Contrast-enhanced ultrasound (CEUS) is a valuable tool in the diagnostic approach of focal liver lesions, but occasionally subjective and observer-dependent. Semiquantitative evaluation of dynamic CEUS (DCEUS) with standardised software programmes such as Dynamic Vascular Pattern (DVP) could help to improve diagnostic accuracy and objectivity in liver tumour assessment. OBJECTIVES: The present study aimed at evaluation of diagnostic accuracy of DVP in a clinical setting. MATERIALS AND METHODS: DVP images of 52 focal liver lesions [30 hepatocellular carcinomas (HCCs), 15 intrahepatic cholangiocellular carcinomas (ICCs), 7 focal nodular hyperplasias (FNHs)] were analysed by four blinded observers with different levels of CEUS-experience. Diagnostic accuracies for the assessment of dignity and entity were evaluated. RESULTS: Mean sensitivity, specificity, positive and negative predictive value for detection of malignancy with DVP were 48.4% /67.8% /92.7% and 29.3%, respectively. Total diagnostic accuracies for dignity/entity were 63.9% /38.5% (HCC: 58.3% /25.8%; ICC: 73.3% /50%; FNH: 67.9% /67.9%). Interreader-agreement was moderate (κ=â0.42-0.58). Differential diagnosis between ICC and HCC was most challenging. CONCLUSION: Although developed to improve diagnostic accuracy and objectivity in the assessment of focal liver lesions, DVP alone seems insufficient for differential diagnosis of HCC, ICC and FNH and cannot replace the skills of an experienced observer.
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Carcinoma Hepatocelular/diagnóstico por imagen , Medios de Contraste/uso terapéutico , Aumento de la Imagen/métodos , Neoplasias Hepáticas/diagnóstico por imagen , Variaciones Dependientes del Observador , Ultrasonografía/métodos , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/fisiopatología , Hiperplasia Nodular Focal/diagnóstico , Humanos , Neoplasias Hepáticas/fisiopatología , Persona de Mediana EdadRESUMEN
PURPOSE: To evaluate automated segmentation and the effects of different manual adjustments regarding left ventricular parameter quantification in cardiac magnetic resonance (MR) data on children and adolescents who have undergone surgical repair of right-sided congenital heart disease (CHD). MATERIALS AND METHODS: Dedicated software (syngo.via, Siemens AG) was used to automatically segment and/or manually adjust the end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), myocardial mass (MM) and ejection fraction (EF) before/after manual apex/base adjustment (ADJ-step 1) and after manual apex/base/myocardial contour adjustment (ADJ-step 2; reference standard). MR data of 40 patients (13.1 ± 3. y, 4 - 17 y) with repaired CHD with decreased pulmonary blood flow (CHD-DPBF) were evaluated. Intra- and inter-rater reliability was determined for 10 randomly selected patients. RESULTS: The software correctly detected the left ventricle in 38/40 (95%) patients. EDV after automated segmentation: 119.1 ± 44.0 ml; after ADJ-step 1: 115.8 ± 9.5 ml; after ADJ-step 2: 116.2 ± 39.4 ml. The corresponding results for ESV were 52.0 ± 18.5/49.6 ± 6.9/49.7 ± 16.4 ml; for SV 67.1 ± 28.5/66.2 ± 25.4/66.5 ± 25. ml; for EF 55.5 ± 7.3/56.7 ± 6.6/56.7 ± 6.3%; for MM 83.7 ± 35.9/76.2 ± 8.3/74.6 ± 27.2 g. Significant differences were found for ESV/MM/EF comparing the automated segmentation results with these after ADJ-step 1 and ADJ-step 2. No significant differences were found when comparing all results of ADJ-step 1 and ADJ-step 2 or when comparing EDV/SV results. Intra- and inter-rater reliability was excellent. The mean time effort was 63.4 ± 6.9 s for the automated segmentation, 74.2 ± 8.9 s for ADJ-step 1 and 269.5 ± 39.4 s for ADJ-step 2. CONCLUSION: Automated left ventricular volumes and function analysis in children and adolescents with surgically treated CHD proved to be feasible with excellent intra- and inter-rater reliability. Automated segmentation with manual apex/base adjustment provided clinically acceptable results. KEY POINTS: Automated left ventricular volume and function analysis in children and adolescents with surgically treated right-sided heart disease is feasible with excellent intra- and inter-rater reliability. Automated segmentation with manual apex/base adjustment provides clinically acceptable results. Additional manual myocardial contour adjustment does not significantly improve the results.
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Volumen Cardíaco/fisiología , Medios de Contraste , Cardiopatías Congénitas/fisiopatología , Cardiopatías Congénitas/cirugía , Ventrículos Cardíacos/anomalías , Ventrículos Cardíacos/fisiopatología , Ventrículos Cardíacos/cirugía , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Contracción Miocárdica/fisiología , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/fisiopatología , Volumen Sistólico/fisiología , Disfunción Ventricular Izquierda/diagnóstico , Adolescente , Algoritmos , Niño , Preescolar , Femenino , Cardiopatías Congénitas/diagnóstico , Humanos , Masculino , Miocardio/patología , Estudios Retrospectivos , Programas Informáticos , Disfunción Ventricular Izquierda/fisiopatologíaAsunto(s)
Eosinofilia/diagnóstico , Fascitis/diagnóstico , Adulto , Anciano , Biopsia , Femenino , Humanos , Imagen por Resonancia Magnética , MasculinoAsunto(s)
Cateterismo/efectos adversos , Neoplasias Esofágicas/complicaciones , Estenosis Esofágica/terapia , Neoplasias Glandulares y Epiteliales/complicaciones , Rotura del Bazo/etiología , Anciano , Estenosis Esofágica/etiología , Esofagoscopía/efectos adversos , Humanos , Rotura del Bazo/diagnóstico , Rotura del Bazo/cirugía , Tomografía Computarizada por Rayos XRESUMEN
The aim of this article was to obtain initial experiences with fluoroscopically triggered contrast-enhanced (CE) 3D MR DSA with elliptical centric k-space order and 3D time-of-flight (TOF) turbo MRA of the carotid arteries. In this prospective study we examined 16 consecutive patients with suspicion of atherosclerotic disease involving the carotid arteries. Ultrasound was available in all, x-ray angiography in 12, surgical correlation in 9, and intraoperative x-ray angiography in 4 patients. All examinations were done on a 1.5 T unit applying: transverse plain 3D TOF turbo MRA and coronal CE MRA with fluoroscopic triggering. Combining head and neck array coils allowed the visualization of supraaortic arteries from the aortic arch to the circle of Willis. MRA results (maximum intensity projections) were compared with x-ray angiography, ultrasound, and inspection of endarterectomy specimens. Volume rendering was performed in selected cases additionally. Agreement between CE MRA, 3D TOF turbo MRA and x-ray angiography regarding stenoses of the internal and external carotid artery was very good. CE MRA was able to detect correctly intracranial stenoses, but delineation of the aortic arch and proximal common carotid arteries was sometimes reduced. Volume rendering was suited for visualization of MRA images providing a realistic three-dimensional impression. In conclusion, high-resolution fluoroscopically triggered CE MRA as non-invasive technique is another important step on the way to replace invasive x-ray angiography for the evaluation of atherosclerotic carotid artery disease. High resolution 3D TOF turbo MRA might be a helpful adjunct to increase the diagnostic reliability for the carotid bifurcation.
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Arterias Carótidas/anatomía & histología , Angiografía por Resonancia Magnética/métodos , Anciano , Anciano de 80 o más Años , Angiografía , Arterias Carótidas/diagnóstico por imagen , Medios de Contraste , Endarterectomía/métodos , Femenino , Fluoroscopía/métodos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , UltrasonografíaRESUMEN
PURPOSE: We introduce a hybrid technique which allows a high resolution MRA of the peripheral arteries with a dedicated phased-array coil using the floating table technique. MATERIALS AND METHODS: Five patients with peripheral arterial occlusive disease were examined within one week with i.a. DSA and MRA using the hybrid technique. MRA examinations were done on a 1.5 T system. At first, pelvic arteries were examined in a single step mode applying the CareBolus technique. Subsequently, thighs and lower legs were examined using the floating table mode. 125 vascular segments were evaluated. RESULTS: The hybrid technique proved to be robust and could be performed in each case. Mean examination time was about 30 min. For 117 vascular segments no difference was found between i.a. DSA and MRA. Three segments revealed a higher grade of stenosis in DSA than in MRA, five segments were graded higher in MRA than in DSA. Occlusions were visualized identically in both methods. Venous overlap had no relevant effects on image evaluation. CONCLUSIONS: This hybrid technique in combination with phased-array coils allows a high resolution MRA of the peripheral arteries with very good image quality. If future studies confirm reduced venous overlap, this method may be an alternative also for users of the floating table MRA with the body resonator.
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Arteriopatías Oclusivas/diagnóstico , Angiografía por Resonancia Magnética/métodos , Arteriopatías Oclusivas/diagnóstico por imagen , Automatización , Humanos , Angiografía por Resonancia Magnética/instrumentación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos XRESUMEN
Magnetic resonance angiography (MRA) is increasingly used as a non-invasive alternative to digital subtraction angiography (DSA). Besides plain time-of-flight (TOF) and phase contrast (PC) MRA a new MRA technique using positive contrast agent has been introduced recently. A fast 3D gradient-echo sequence is applied to reach a significant reduction of measurement time for acquisition of the MRA within the first pass of the contrast agent, thereby avoiding venous overlap. A significant progress was yielded by MR systems allowing manual table movement for examination of the pelvis and the lower limbs in one examination with a single contrast agent bolus. However, in this case it is necessary to have a coworker in the examination room moving the table manually. In this paper we report a prototype system which allows automatic table movement ("floating table"). Using this novel system we examined a patient with an aneurysm of the abdominal aorta and peripheral arterial occlusive disease (PAOD). Diagnostic results of contrast enhanced MRA and DSA were equivalent. In summary, the automatic floating table system introduced in this paper allows comfortable non-invasive examination of pelvic and lower limb arteries. The value of this technique in comparison to DSA has to be determined in future studies.
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Arteriopatías Oclusivas/diagnóstico , Angiografía por Resonancia Magnética , Enfermedades Vasculares Periféricas/diagnóstico , Medios de Contraste , HumanosRESUMEN
Gd-BOPTA is a new positive MR contrast agent for intravenous application. In comparison to other gadolinium-chelates it has a nearly two-fold increased relaxivity due to weak protein binding with plasmatic macromolecules. In the papers published yet it has been evaluated to be useful for liver imaging. The purpose of this study was to evaluate, whether Gd-BOPTA is suited as an "magnetic resonance angiography (MRA) contrast agent". We examined four patients (aortic dissection, carotid artery stenosis, portal vein stenosis, exclusion of subclavian artery stenosis) with Gd-BOPTA with a dosage of 0.05 mmol/kg body weight. Furthermore, peripheral MRA of the pelvis and lower extremities was acquired in two healthy volunteers comparing 0.1 mmol Gd-DTPA/kg with 0.1 mmol Gd-BOPTA/kg. There was a delay of one week between the Gd-DTPA and the Gd-BOPTA examinations. In another volunteer Gd-BOPTA was reduced to 0.05 mmol/kg. The patient examinations revealed sufficient quality comparable with Gd-DTPA examinations despite of reduced dosage. In the volunteers Gd-BOPTA proved to be superior especially in the delineation of small pedal arteries which is important for surgical planning. These preliminary results demonstrate the potential of Gd-BOPTA to become a useful contrast agent for MRA. Its efficacy for this purpose has to be evaluated in future prospective studies.
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Gadolinio , Compuestos Heterocíclicos , Angiografía por Resonancia Magnética/métodos , Meglumina , Compuestos Organometálicos , Enfermedades Vasculares/diagnóstico , Estenosis de la Válvula Aórtica/diagnóstico , Quelantes , Medios de Contraste , Humanos , Arteria Subclavia/fisiopatologíaRESUMEN
The aim of this study was to obtain first clinical experiences with magnetic resonance angiography (MRA) with digital subtraction (MR-DSA) using an automatic floating table for visualization peripheral arteriosclerotic occlusive disease (paod). We examined 10 patients on a 1.5 T MR unit applying a fast MRA technique (3D FLASH) with intravenous application of positive contrast agent. MR-DSA examinations were compared with the gold standard intraarterial (i.a.) DSA. MR-DSA proved to be useful for routine application which could be performed sufficiently in all patients. MR-DSA and i.a. DSA showed comparable results for imaging of the pelvic and upper leg arteries. Looking at the thighs image quality of MR-DSA did not match the image quality of i.a. DSA in every case. This was due to venous overlap and in comparison to i.a. DSA reduced signal-to-noise ratios. However, clinical findings, obtained with MR-DSA, were sufficient for adequate therapy planning. Our preliminary results reveal the potential of this new technique to become a realistic, robust, and non-invasive alternative to i.a. DSA in the diagnosis of paod.
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Angiografía de Substracción Digital , Arteriopatías Oclusivas/diagnóstico , Arteriosclerosis/diagnóstico , Isquemia/diagnóstico , Pierna/irrigación sanguínea , Angiografía por Resonancia Magnética/instrumentación , Anciano , Arterias/patología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Masculino , Persona de Mediana EdadRESUMEN
PURPOSE: To analyze the exactness of MRI-compatible contrast media (CM) injectors in an experimental setup and clinical use. MATERIALS AND METHODS: Ejected fluid volumes and amounts of CM were quantified for single and double piston injections. The focus was on small volumes, as used in pediatric examination and test-bolus measurements. Samples were collected before and after clinical MRI scans and amounts of CM were measured. RESULTS: For single piston injections the volume differences were minimal (mean difference 0.01â ml). For double piston injections the volume of the first injection was decreased (mean 20.74 âml, target 21.00 âml, pâ<â0.01). After a position change of the Y-piece of the injection system, the amount of CM differed significantly from the target value (mean 1.23 âmmol and 0.83 âmmol at 1 âml/s flow rate, target 1.00â mmol, pâ<â0.01), independently of the wait time. The clinical samples confirmed these findings. CONCLUSION: The pistons of modern CM injectors work exactly. However, for small CM volumes the injected amount of CM can differ significantly from the target value in both directions. Influence factors are an incomplete elimination of air and exchange processes between the CM and saline chaser in the injection system. KEY POINTS: â¢âIn MRI examinations of children and test-bolus measurements, small amounts of CM are used. â¢âThe accuracy of single piston injections is high. â¢âIn double piston injections the injected amount of CM can differ significantly from the target value.
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Medios de Contraste/administración & dosificación , Medios de Contraste/análisis , Inyecciones Intravenosas/instrumentación , Imagen por Resonancia Magnética/instrumentación , Jeringas , Diseño de Equipo , Análisis de Falla de Equipo , Imagen por Resonancia Magnética/métodos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: We report a patient with recurrent shock and transient non-cardiogenic pulmonary edema within a period of two months - every time occurring after cataract surgery and a single oral dose of standard post-operative medication with acetazolamide. DATA SOURCES: Records of the intensive care unit, review of the literature. CONCLUSIONS: This case demonstrates a rare but severe side effect of acetazolamide. We also present a review of the literature to raise the awareness of health care providers for this special form of non-cardiogenic pulmonary edema.
Asunto(s)
Acetazolamida/efectos adversos , Inhibidores de Anhidrasa Carbónica/efectos adversos , Extracción de Catarata , Edema Pulmonar/inducido químicamente , Choque/inducido químicamente , Acetazolamida/administración & dosificación , Anciano , Inhibidores de Anhidrasa Carbónica/administración & dosificación , Humanos , Masculino , Hipertensión Ocular/prevención & control , Complicaciones Posoperatorias/prevención & controlRESUMEN
PURPOSE: Many publications describe the use of diffusion-weighted imaging (DWI) in breast MRI. This article addresses the question of when to apply the DWI sequence in the course of the scan protocol. The effect of T1-shortening contrast media (CM) on the ADC values of breast lesions is investigated. MATERIALS AND METHODS: Data were acquired on a 1.5âT scanner. 60 patients with 79 lesions (20 benign, 59 malignant) were included. The DWI sequence (4âmm slice thickness, b-values: 50, 400, 800) was applied before and after CM administration. Before calculating the ADC map, the b50, b400 and b800 series were analyzed concerning lesion displacement. ADC values before and after CM application were compared. RESULTS: The mean lesion size was 1.5â±â0.8âcm. On the basis of the b50 and b400 measurements, the mean ADC value of benign lesions was 1.89â± 0.30â×â10-3âmm2/s before and 1.85â±â0.28â×10-3 mm2/s after CM administration. The consecutive values for two pure mucinous carcinomas were 1.88â×â10-3âmm2/s and 1.81â×â103âmm2/s and for the remaining malignant lesions 1.00â±â0.18â×â10-3 mm2/s and 0.88â±â0.21â×â10-3âmm2. On the basis of the b50, b400 and b800 measurements, the mean ADC value of benign lesions was 1.99â± 0.37â×â10-3âmm2/s before and 1.97â±â0.30â×â10-3âmm2/s after CM application, whereas the mean ADC value of the malignant lesions was 0.90â±â0.14â×â10-3âmm2/s before and 0.80â±â0.14â×â10-3âmm2/s after CM application. While there was no significant change for benign lesions, the ADC value decrease in post-contrast malignant lesions was highly significant. CONCLUSION: DWI after CM is possible and even leads to slightly better lesion discrimination between benign and malignant. However, further studies need to be performed to verify this. Citation Format: â¢âJanka R, Hammon M, Geppert C etâal. Diffusion-Weighted MR Imaging of Benign and Malignant Breast Lesions Before and After Contrast Enhancement. Fortschr Röntgenstr 2014; 186: 130â-â135.