RESUMEN
BACKGROUND: In patients with hepatic neuroendocrine tumors (NETs) locoregional therapies such as transarterial radioembolization (TARE) are increasingly applied. Response evaluation remains challenging and previous studies assessing response with diffusion-weighted imaging (DWI) have been inconclusive. PURPOSE: To perform a feasibility study to evaluate if response assessment with quantitative apparent diffusion coefficient (ADC) in patients with liver metastases of NETs after TARE will be possible. MATERIAL AND METHODS: Retrospectively, 43 patients with 120 target lesions who obtained abdominal magnetic resonance imaging (MRI) with DWI 39±28 days before and 74±46 days after TARE were included. Intralesional ADC (ADCmin, ADCmax, and ADCmean) were measured for a maximum number of three lesions per patient on baseline and post-interventional DWI. Tumor response was categorized according to RECIST 1.1 and mRECIST. RESULTS: TARE resulted in partial remission (PR) in 23% (63%), in stable disease (SD) in 73% (23%), in progressive disease (PD) in 5% (7%) and in complete response (CR) in 0% (1%) according to RECIST 1.1 (mRECIST, respectively). ADC values increased significantly (P<0.005) after TARE in the PR group whereas there was no significant change in the PD group. Post-therapeutic ADC values of SD lesions increased significantly when evaluated by RECIST 1.1 but not if evaluated by mRECIST. Percentual changes of ADCmean values were slightly higher for responders compared to non-responders (P<0.05). CONCLUSION: ADC values seem to represent an additional marker for treatment response evaluation after TARE in patients with secondary hepatic NET. A conclusive study seems feasible though patient-based evaluation and overall survival and progression free survival as alternate primary endpoints should be considered.
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Embolización Terapéutica , Neoplasias Hepáticas , Tumores Neuroendocrinos , Imagen de Difusión por Resonancia Magnética/métodos , Embolización Terapéutica/métodos , Estudios de Factibilidad , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/radioterapia , Tumores Neuroendocrinos/diagnóstico por imagen , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
OBJECTIVES: To assess the diagnostic accuracy (ACC) of post-mortem computed tomography (PMCT) for fractures of the isolated larynx-hyoid complex (LHC) in comparison to post-mortem fine preparation (PMFP). METHODS: This monocentric prospective study enclosed 54 LHCs that were extracted during autopsy, fixed in formalin, and underwent a PMCT scan (64-row multidetector CT, helical pitch). Two radiologists independently analyzed the LHC scans for image quality (IQ) and fractures (4-point Likert scales). A specialized forensic preparator dissected the specimens under the stereomicroscope. The PMFP results were standardized documented, and used as the standard of reference for the comparison to PMCT. RESULTS: The PMCT-IQ of 95% of the LHC images was rated as good or excellent. IQ was decreased by decay, incisions during autopsy, and separation of the hyoid from the cartilaginous components in 7, 3, and 12 specimens, respectively. PMFP detected 119 fractures in 34 LHCs (63.0%). PMCT identified 91 fractures in 32 specimens (59.3%). PMFP and PMCT significantly agreed concerning the location (Cohen's κ = 0.762; p < 0.001) and the degree of dislocation (κ = 0.689; p < 0.001) of the fractures. Comparing PMCT to PMFP resulted in a sensitivity of 88.2%, a specificity of 90.0%, and an ACC of 88.9% for the LHC. The ACCs for the hyoid, thyroid, and cricoid were 94.4%, 87.0%, and 81.5%, respectively. PMCT procedure was significantly faster than PMFP (28.9 ± 4.1 min vs. 208.2 ± 32.5 min; p < 0,001). CONCLUSIONS: PMCT can detect distinct injuries of the isolated LHC and may promptly confirm violence against the neck as cause of death. PMFP outmatches PMCT in the detection of decent injuries like tears of the cricoid cartilage. KEY POINTS: ⢠Post-mortem computed tomography is able to assess fractures of the larynx-hyoid complex. ⢠Prospective monocentric in vitro study showed that post-mortem computed tomography of the larynx-hyoid complex is faster than post-mortem fine preparation. ⢠Post-mortem computed tomography can confirm violence against the neck as cause of death.
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Medicina Legal/métodos , Fracturas Óseas/diagnóstico por imagen , Hueso Hioides/diagnóstico por imagen , Hueso Hioides/lesiones , Laringe/diagnóstico por imagen , Laringe/lesiones , Tomografía Computarizada Multidetector/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Autopsia , Causas de Muerte , Estudios de Cohortes , Femenino , Humanos , Técnicas In Vitro , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto JovenRESUMEN
PURPOSE: To assess the diagnostic value of intima media thickness measurements and contrast-enhanced ultrasound (CEUS) of the supraaortic arteries in the assessment of disease activity in Takayasu arteritis (TA). MATERIALS AND METHODS: Patients with TA and involvement of the carotid and/or subclavian/axillary arteries underwent CEUS imaging in addition to B-mode and color duplex ultrasound. The maximum IMT (mIMT) was measured and high-resolution CEUS of the most prominently thickened vessel segment was performed. Two blinded readers reviewed the CEUS movies, with semiquantitative assessment of microbubble enhancement of the arterial wall (grade 0: no or minimal; grade 1: moderate; grade 2: pronounced). Clinical symptoms, acute phase reactants, and established indices of clinical disease activity (NIH criteria, ITAS score) were recorded. RESULTS: 40 examinations in 17 patients were analyzed. According to clinical judgement, 27 and 13 cases were classified as clinically inactive and active, respectively. An mIMT-cutoff of >â2.7âmm identified active disease with a sensitivity and specificity of 69.2â% and 88.9â%, respectively (area under the curve 0.83). The interobserver agreement of CEUS analysis was substantial (Cohen's kappa 0.76). By consensus reading, 17, 15, and 8 cases were classified as uptake grade 0, grade 1 and grade 2, respectively. Grade 0 uptake was exclusively present in 17 clinically inactive patients. Grade 1 uptake was seen in 10 patients with clinically inactive disease and 5 patients with clinically active disease. Grade 2 uptake was exclusively present in 8 patients with active disease. CONCLUSION: Both sonographic IMT measurements and high-resolution CEUS are promising in the ad-hoc assessment of disease activity in patients with TA.
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Medios de Contraste , Arteritis de Takayasu , Ultrasonografía/métodos , Adulto , Grosor Intima-Media Carotídeo , Femenino , Humanos , Masculino , Sensibilidad y Especificidad , Arteritis de Takayasu/diagnóstico por imagen , Arteritis de Takayasu/patologíaRESUMEN
Takayasu arteritis (TA) is a rare large vessel vasculitis, affecting the aorta and its major branches, typically in young women. In this case report, we present three cases of young women of Caucasian descent who experienced relapses while under treatment with the monoclonal humanized antibody to the interleukin 6 receptor, tocilizumab. Active vasculitic lesions of the supraaortic (common carotid and axillary) arteries were detected and characterized via high resolution contrast enhanced ultrasound. Based on these cases, we discuss the potential role of contrast enhanced ultrasound in the diagnosis and follow-up of TA as well as the current data on the efficacy of tocilizumab in the treatment of TA.
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Antiinflamatorios/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Arteria Axilar/diagnóstico por imagen , Arteria Carótida Común/diagnóstico por imagen , Medios de Contraste/administración & dosificación , Fosfolípidos/administración & dosificación , Hexafluoruro de Azufre/administración & dosificación , Arteritis de Takayasu/diagnóstico por imagen , Arteritis de Takayasu/tratamiento farmacológico , Ultrasonografía Doppler en Color , Adulto , Femenino , Humanos , Valor Predictivo de las Pruebas , Recurrencia , Arteritis de Takayasu/inmunología , Resultado del Tratamiento , Adulto JovenRESUMEN
OBJECTIVE: To analyse the patency rates of femoro-popliteal stenting with different self-expandable Nitinol stent-designs. METHODS: Two hundred and twenty-two patients (142 (64%) male; age 72.4 ± 11.6 years) with symptomatic femoro-popliteal peripheral arterial occlusive disease (PAOD) underwent percutaneous transluminal angioplasty (PTA) and stenting with three different Nitinol stents (interwoven IW: n = 70; closed-cell CC: n = 85; open-cell OC: n = 67). One-year post-procedural target lesion revascularization (TLR_12M) rates were investigated with regard to co-morbidities: diabetes (DBM), hyperlipidaemia (HLP), hypertension (RR), coronary artery disease (CAD) and degree of calcification. RESULTS: Twelve-month follow-up data were available for 60, 69 and 50 patients in the IW, OC and CC groups (179 patients in total). The cumulative patency (IW: 52 (86.7%); OC: 50 (72.5%); CC: 23 (46.0%); P < 0.001) and the TLR_12M rates (IW: 8 (13.3%); OC: 19 (27.5%); CC: 27 (54.0%); P < 0.001) differed significantly, as did the subgroup analyses (DBM: P = 0.05; RR: P = 0.003; HLP: P = 0.005; CAD: P = 0.02; localization: P < 0.001; calcification: P < 0.001), with the best patency for the IW stent and the highest TLR_12M for the CC stent. CONCLUSION: The interwoven stent-design was superior to the standard open- and closed-cell stent-designs in endovascular treatment of femoro-popliteal PAOD in a follow-up period of 12 months. KEY POINTS: ⢠Results of femoro-popliteal stenting are still unsatisfactory. ⢠Comparative studies for currently available different Nitinol stent-designs are lacking. ⢠This is a first comparative study on long-term patency of different Nitinol stent-designs. ⢠Interwoven stent-design leads to improved long-term patency. ⢠Interwoven stent-design leads to lower TLR than other stent-designs.
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Angioplastia/instrumentación , Arteriopatías Oclusivas/cirugía , Arteria Femoral/cirugía , Arteria Poplítea/cirugía , Stents , Anciano , Aleaciones/uso terapéutico , Angioplastia/métodos , Angioplastia de Balón/métodos , Arteriopatías Oclusivas/patología , Enfermedad de la Arteria Coronaria/fisiopatología , Femenino , Humanos , Masculino , Enfermedad Arterial Periférica/patología , Enfermedad Arterial Periférica/cirugía , Diseño de Prótesis , Reperfusión/métodos , Resultado del Tratamiento , Grado de Desobstrucción Vascular/fisiologíaRESUMEN
OBJECTIVES: To evaluate the feasibility of T1w-3D black-blood turbo spin echo (TSE) sequence with variable flip angles for the diagnosis of thoracic large vessel vasculitis (LVV). METHODS: Thirty-five patients with LVV, diagnosed according to the current standard of reference, and 35 controls were imaged at 3.0T using 1.2 × 1.3 × 2.0 mm3 fat-suppressed, T1w-3D, modified Volumetric Isotropic TSE Acquisition (mVISTA) pre- and post-contrast. Applying a navigator and peripheral pulse unit triggering (PPU), the total scan time was 10-12 min. Thoracic aorta and subclavian and pulmonary arteries were evaluated for image quality (IQ), flow artefact intensity, diagnostic confidence, concentric wall thickening and contrast enhancement (CWT, CCE) using a 4-point scale. RESULTS: IQ was good in all examinations (3.25 ± 0.72) and good to excellent in 342 of 408 evaluated segments (83.8 %), while 84.1 % showed no or minor flow artefacts. The interobserver reproducibility for the identification of CCE and CWT was 0.969 and 0.971 (p < 0.001) with an average diagnostic confidence of 3.47 ± 0.64. CCE and CWT were strongly correlated (Cohen's k = 0.87; P < 0.001) and significantly more frequent in the LVV-group (52.8 % vs. 1.0 %; 59.8 % vs. 2.4 %; P < 0.001). CONCLUSIONS: Navigated fat-suppressed T1w-3D black-blood MRI with PPU-triggering allows diagnosis of thoracic LVV. KEY POINTS: ⢠Cross-sectional imaging is frequently applied in the diagnosis of LVV. ⢠Navigated, PPU-triggered, T1w-3D mVISTA pre- and post contrast takes 10-12 min. ⢠In this prospective, single-centre study, T1w-3D mVISTA accurately depicted large thoracic vessels. ⢠T1w-3D mVISTA visualized CWT/CCW as correlates of mural inflammation in LVV. ⢠T1w-3D mVISTA might be an alternative diagnostic tool without ionizing radiation.
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Imagen por Resonancia Magnética/métodos , Vasculitis/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Aorta Torácica/diagnóstico por imagen , Aortitis/diagnóstico por imagen , Artefactos , Estudios de Factibilidad , Femenino , Arteritis de Células Gigantes/diagnóstico por imagen , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Arteria Pulmonar/diagnóstico por imagen , Reproducibilidad de los Resultados , Arteria Subclavia/diagnóstico por imagen , Arteritis de Takayasu/diagnóstico por imagen , Ultrasonografía Doppler en Color/métodos , Ultrasonografía Doppler Dúplex/métodos , Adulto JovenRESUMEN
OBJECTIVES: We aimed to determine the diagnostic accuracy of B-mode compression sonography of the temporal arteries (tempCS) and B-mode sonographic measurement of the axillary artery intima media thickness (axIMT) for the diagnosis of giant cell arteritis (GCA). METHODS: After having established measurement of tempCS and axIMT in our routine diagnostic workup, 92 consecutive patients with a suspected diagnosis of GCA were investigated. Clinical characteristics were recorded and wall thickening of the temporal arteries (tempCS) and axillary arteries (axIMT) was measured (mm). Using the final clinical diagnosis as the reference standard, receiver operator characteristics (ROC) analysis was performed. In a subgroup of 26 patients interobserver agreement was assessed using Spearman's rank correlation. RESULTS: Cranial GCA, extracranial GCA, and combined cranial/extracranial GCA were diagnosed in 18, 7, and 9 individuals, respectively. For the diagnosis of cranial GCA, tempCS had an excellent area under the curve (AUC) of 0.95, with a cut-off of ≥0.7 mm offering a sensitivity and specificity of 85% and 95%. The AUC of axIMT for the diagnosis of extracranial GCA was 0.91 (cut-off ≥1.2 mm: sensitivity and specificity 81.3 and 96.1%). Applying a combined tempCS/axIMT cut-off of ≥0.7mm/1.2 mm, we calculated an overall sensitivity and specificity for the final clinical diagnosis of cranial and/or extracranial GCA of 85.3% and 91.4%. Interobserver agreement was strong for both parameters assessed (Spearman's rho 0.72 and 0.77, respectively). CONCLUSIONS: The combination of tempCS/axIMT allows objective sonographic assessment in suspected GCA with promising diagnostic accuracy.
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Arteria Axilar/diagnóstico por imagen , Arteritis de Células Gigantes/diagnóstico por imagen , Arterias Temporales/diagnóstico por imagen , Ultrasonografía Doppler en Color , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Curva ROC , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
OBJECTIVES: We report our experience with polidocanol foam sclerotherapy with no additional coils, evaluating clinical success, patients' satisfaction, and complications. METHODS: We conducted a retrospective study of 141 patients with 146 varicoceles (mean age: 29.3 years; range: 13 - 60 years) who underwent foam sclerotherapy with polidocanol 2% (range: 2 - 12 ml) in an outpatient setting between January 2007 and December 2013. For the follow-up, telephone interviews with the patients were conducted (mean follow-up time: 46.4 months, standard deviation: 20.17 months). RESULTS: The technical success rate was 91.8%. There was a 55.8% response rate to the telephone interviews. Follow-up revealed a clinical success rate of 83.9% and a persistence or relapse rate of 16.1%. Of the patients, 81.9% were absolutely satisfied with the outcome. In 94.9% of cases, pain or discomfort resolution was reported, and in 97% of cases, aesthetic issues were no longer a problem. Of partners, 63.2% achieved pregnancy, and in 50% of patients with preprocedural testicular atrophy, catch-up growth was observed. One patient with pampiniform plexus phlebitis received inpatient treatment with no long-term damage recorded. CONCLUSIONS: Polidocanol foam varicocele sclerotherapy is a safe and effective procedure, with a high rate of patients' satisfaction, clinical and technical success, and considerable catch-up growth and pregnancy achievement. KEY POINTS: ⢠Varicocele treatment using polidocanol foam sclerotherapy is a safe and effective procedure. ⢠It is easily feasible in an outpatient setting. ⢠The clinical and technical success rates are high. ⢠It shows a high rate of patients' satisfaction and symptom resolution. ⢠Postinterventional catch-up growth and pregnancy achievement are considerable.
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Polietilenglicoles/administración & dosificación , Soluciones Esclerosantes/administración & dosificación , Testículo/patología , Varicocele/terapia , Adolescente , Adulto , Atrofia/patología , Cateterismo/métodos , Estudios de Factibilidad , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Polidocanol , Polietilenglicoles/efectos adversos , Recurrencia , Estudios Retrospectivos , Soluciones Esclerosantes/efectos adversos , Escleroterapia/efectos adversos , Escleroterapia/métodos , Resultado del Tratamiento , Adulto JovenRESUMEN
OBJECTIVES: Radiation exposure of patients during endovascular aneurysm repair (EVAR) procedures ranks in the upper sector of medical exposure. Thus, estimation of radiation doses achieved during EVAR is of great importance. MATERIAL AND METHODS: Organ doses (OD) and effective doses (ED) administered to 17 patients receiving EVAR were determined (1) from the exposure parameters by performing Monte Carlo simulations in mathematical phantoms and (2) by measurements with thermoluminescent dosimeters in a physical anthropomorphic phantom. RESULTS: The mean fluoroscopy time was 26 min, the mean dose area product was 24995 cGy cm2. The mean ED was 34.8 mSv, ODs up to 626 mSv were found. Whereas digital subtraction angiographies (DSA) and fluoroscopies each contributed about 50% to the cumulative ED, the ED rates of DSAs were found to be ten times higher than those of fluoroscopies. Doubling of the field size caused an ED rate enhancement up to a factor of 3. CONCLUSION: EVAR procedures cause high radiation exposure levels that exceed the values published thus far. As a consequence, (1) DSAs should be only performed when necessary and with a low image rate, (2) fluoroscopies should be kept as short as possible, and (3) field sizes should be minimized. KEY POINTS: ⢠During endovascular aneurysm repair (EVAR) considerable patient doses are achieved. ⢠For each EVAR procedure organ (OD) and effective (ED) doses were determined. ⢠The mean ED was 34.8 mSv, the highest OD was 626 mSv. ⢠Number of DSAs, fluoroscopy durations and field sizes should be minimized.
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Aneurisma de la Aorta/diagnóstico por imagen , Aneurisma de la Aorta/cirugía , Procedimientos Endovasculares , Método de Montecarlo , Dosis de Radiación , Anciano , Angiografía de Substracción Digital , Aorta/cirugía , Aortografía , Simulación por Computador , Femenino , Fluoroscopía , Humanos , Masculino , Fantasmas de Imagen , Estudios Prospectivos , Factores de TiempoRESUMEN
PURPOSE: To prospectively assess current limitations and complication rates of the transbrachial access technique for endovascular treatment of peripheral vascular pathologies. METHODS: In total, 150 patients (112 men; mean age 66.3 ± 10.0 years) with arterial occlusive disease underwent endovascular therapy via a transbrachial access. Periprocedure data (sheath size, dose area product, fluoroscopy time, and procedure duration) were analyzed. Postprocedure complications of the puncture sites were categorized as minor (local hematoma, pseudoaneurysm, embolization, dissection, minor bleeding) and major (thrombotic occlusion, hematoma requiring surgery, major bleeding, nerve injury). RESULTS: The minor and major complication rates were 14.0% (n = 21) and 2.7% (n = 4). The most frequent major complication was thrombotic occlusion of the brachial artery requiring surgical treatment (3/150, 2%). There was only one temporary palsy of the median nerve and no stroke. Local hematoma (15, 10%), pseudoaneurysm (3, 2%), or a combination of both (3, 2%) dominated the minor complications. The average dose area product and fluoroscopy time were 12,752.1 ± 9524.5 cGy*cm(2) and 24.3 ± 18.4 minutes, respectively, though procedure duration was acceptable (121.8 ± 48.9 minutes). CONCLUSION: Complication rates of the transbrachial access for endovascular treatment of peripheral or visceral artery occlusive disease are tolerably low, making it a safe and an important alternative to the transfemoral access in selected cases, though the radiation exposure is rather high.
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Arteria Braquial , Cateterismo Periférico , Stents Liberadores de Fármacos , Enfermedad Arterial Periférica/terapia , Adulto , Anciano , Anciano de 80 o más Años , Cateterismo Periférico/efectos adversos , Clopidogrel , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/diagnóstico por imagen , Inhibidores de Agregación Plaquetaria/administración & dosificación , Estudios Prospectivos , Punciones/efectos adversos , Factores de Riesgo , Ticlopidina/administración & dosificación , Ticlopidina/análogos & derivados , Resultado del Tratamiento , UltrasonografíaRESUMEN
OBJECTIVES: To evaluate the safety and efficacy of a filter embolic protection device (FEPD) in endovascular interventions of the femoropopliteal arteries. METHODS: Patients who underwent endovascular interventions of the femoropopliteal arteries between 2008 and 2016 and in whom the SpiderFXTM FEPD was applied were included in this retrospective study. Clinical and angiographic characteristics, filter macroembolization (FME), device-related complications, distal embolization, as well as the early clinical and hemodynamic outcome, were assessed. Potential risk factors for FME were evaluated by multivariate analysis. RESULTS: A total of 244 cases were identified (203 patients, claudication 60.4%, critical limb ischaemia 39.6%, mean lesion length 13.2 ± 12.9 cm, complete occlusions in 72.7%). Balloon angioplasty ± stenting (BAP), directional atherectomy ± balloon angioplasty ± stenting (DA) and rotational thrombectomy ± balloon angioplasty ± stenting (RT) were performed in 141, 61 and 42 cases, respectively. FEPD placement and retrieval were successful in all but one case each. Permanent filter-related vessel damage was not observed. The rate of FME was 37.3% (BAP 36.2%, DA 32.8%, RT 47.7%). Risk factors for FME in the BAP- and DA-group were total occlusion, lesion length > 19 cm, visible thrombus and diabetes mellitus. The distal embolization rate despite filter protection was 4.1 % (BAP 4.9%, DA 1.6%, RT 4.8%) and was higher in cases with FME compared with those without FME (8.7% vs. 1.5%, p = 0.02). CONCLUSION: The Spider FXTM device is safe and effective in capturing embolic debris during femoropopliteal interventions. A residual risk of peripheral embolization remains. LEVEL OF EVIDENCE: III, Cohort study.
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Dispositivos de Protección Embólica , Embolia/prevención & control , Procedimientos Endovasculares/efectos adversos , Arteria Femoral/cirugía , Claudicación Intermitente/cirugía , Arteria Poplítea/cirugía , Anciano , Estudios de Cohortes , Embolia/etiología , Femenino , Humanos , Masculino , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del TratamientoRESUMEN
This study investigates the x-ray scattering characteristics of microsphere particles in x-ray-grating-based interferometric imaging at different concentrations, bubble sizes and tube voltages (kV). Attenuation (ATI), dark-field (DFI) and phase-contrast (PCI) images were acquired. Signal-to-noise (SNR) and contrast-to-noise ratios with water (CNRw) and air as reference (CNRa) were determined. In all modalities, a linear relationship between SNR and microbubbles concentration, respectively, microsphere size was found. A significant gain of SNR was found when varying kV. SNR was significantly higher in DFI and PCI than ATI. The highest gain of SNR was shown at 60 kV for all media in ATI and DFI, at 80 kV for PCI. SNR for all media was significantly higher compared to air and was slightly lower compared to water. A linear relationship was found between CNRa, CNRw, concentration and size. With increasing concentration and decreasing size, CNRa and CNRw increased in DFI, but decreased in PCI. Best CNRa and CNRw was found at specific combination of kV and concentration/size. Highest average CNRa and CNRw was found for microspheres in ATI and PCI, for microbubbles in DFI. Microspheres are a promising contrast-media for grating-based-interferometry, if kV, microsphere size and concentration are appropriately combined.
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Medios de Contraste/química , Radiografía/métodos , Tomografía Computarizada por Rayos X/métodos , Microburbujas , Dosis de Radiación , Rayos XRESUMEN
AIM: To determine the diagnostic yield of 18 F-fluorodeoxyglucose positron emission tomography (PET) in disease activity assessment of large vessel vasculitides (LVV). METHODS: Patients with LVV who had undergone PET (between 2004 and June 2010) or PET co-registered with computed tomography (PET/CT; since June 2010) were identified. Clinical disease activity was assessed using established scoring systems. PET images were reviewed by two blinded nuclear medicine physicians. Uptake of the aortic wall was compared to the liver uptake utilizing a visual 4-point score, with a vessel wall uptake similar or higher than liver uptake considered as active disease. Various target-to-background ratios were calculated. Receiver operator characteristics analysis was applied to determine the diagnostic accuracy of PET for detecting clinically active disease. Interobserver agreement of visual readings was measured with Cohen´s kappa. RESULTS: Eighty examinations in 62 patients were analyzed, with a mean time between diagnosis and PET of 106 ± 171 weeks. Fifty-seven cases were finally classified as clinically active and 23 cases as clinically inactive. With a cut-off value of 1.3, the aorta-to-liver ratio yielded a sensitivity and specificity of 84.2% and 82.6% (area under the curve 0.9). Overall, sensitivity and specificity of visual analysis were 68.4% and 91.3%, but sensitivity decreased to 54% in patients treated for more than 3 months. Interobserver agreement of visual rating was excellent (κ: 0.93). CONCLUSION: Positron emission tomography is specific and reliable in disease activity assessment of LVV, but lacks sensitivity for detecting active disease in patients under long-term immunosuppressive treatment.
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Aorta/diagnóstico por imagen , Arteritis de Células Gigantes/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Arteritis de Takayasu/diagnóstico por imagen , Biomarcadores/sangre , Bases de Datos Factuales , Femenino , Fluorodesoxiglucosa F18/administración & dosificación , Arteritis de Células Gigantes/sangre , Humanos , Masculino , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Pronóstico , Radiofármacos/administración & dosificación , Reproducibilidad de los Resultados , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Arteritis de Takayasu/sangreRESUMEN
OBJECTIVES: The objective of this study was to evaluate the feasibility of a novel 3-dimensional turbo spin-echo technique with isotropic resolution for the diagnosis of deep vein thrombosis (DVT) in comparison with contrast-enhanced magnetic resonance imaging (CE-MRI) and sonography. MATERIALS AND METHODS: Thirteen patients (8 males, 17-93 years) with proven DVT in duplex ultrasound (n = 11) or with pulmonary embolism and suspected to have DVT (n = 2) were consecutively imaged at 3.0 T with 1.2-mm isotropic-resolution volumetric isotropic turbo spin-echo acquisition (VISTA). Sensitivity (SE), specificity (SP), positive and negative predictive values (PPV and NPV, respectively), Cohen κ, as well as accuracy of VISTA-MRI were calculated and compared with CE-MRI and sonography as a standard of reference. Image quality and diagnostic confidence were assessed on a 4-point scale. RESULTS: Image quality and diagnostic confidence level of VISTA-MRI and CE-MRI were comparable (3.54 vs 3.55 and 3.80 vs 3.77; both P values are nonsignificant). Using CE-MRI as the criterion standard, there was a high agreement between the CE-MRI and the 3-dimensional VISTA examinations for the detection of DVT, with κ of 0.89 for reader 1 and κ of 0.88 for reader 2 (both P < 0.001). The SE, SP, PPV, NPV, as well as accuracy of VISTA-MRI were 92.5%, 97.9%, 89.3%, 98.6%, and 97.1% for reader 1 as well as 90.7%, 97.9%, 89.1%, 98.3%, and 96.8% for reader 2. For both readers, combined comparison of VISTA-MRI and sonography resulted in an SE, SP, PPV, and NPV of 77.8%, 94.8%, 85.4%, and 91.6%, respectively. CONCLUSIONS: Volumetric isotropic turbo spin-echo acquisition magnetic resonance imaging can be used to diagnose DVT with good to excellent agreement compared with CE-MRI and sonography. It might be useful when contrast media is prohibited and in patients with suspected thrombosis of the iliac veins, which can be hard to detect with sonography.