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1.
Orthopade ; 51(5): 410-414, 2022 May.
Artículo en Alemán | MEDLINE | ID: mdl-35194651

RESUMEN

The intra-articular osteoid osteoma (10% of cases) is a rare clinical finding. Based on atypical clinical signs and various radiological results the period to obtain a diagnosis and initiate the appropriate treatment is often very long. This case reports on a 32-year old female patient with knee pain on flexion and stress, which rarely occurred at night. Radiofrequency ablation (RFA) was contraindicated for IAOO in the trochlea femoris due to the direct subchondral location. Therefore, surgical rehabilitation by means of a cartilage-bone transplantation was carried out.


Asunto(s)
Neoplasias Óseas , Ablación por Catéter , Osteoma Osteoide , Adulto , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/cirugía , Trasplante Óseo , Ablación por Catéter/métodos , Femenino , Humanos , Articulación de la Rodilla/cirugía , Osteoma Osteoide/diagnóstico por imagen , Osteoma Osteoide/cirugía
2.
Int J Mol Sci ; 22(13)2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34202056

RESUMEN

Mesenchymal stem cells (MSC) are known for their vascular regeneration capacity by neoangiogenesis. Even though, several delivery approaches exist, particularly in the case of intravascular delivery, only limited number of cells reach the targeted tissue and are not able to remain on site. Applicated cells exhibit poor survival accompanied with a loss of functionality. Moreover, cell application techniques lead to cell death and impede the overall MSC function and survival. 3D cell spheroids mimic the physiological microenvironment, thus, overcoming these limitations. Therefore, in this study we aimed to evaluate and assess the feasibility of 3D MSCs spheroids for endovascular application, for treatment of ischemic peripheral vascular pathologies. Multicellular 3D MSC spheroids were generated at different cell seeding densities, labelled with ultra-small particles of iron oxide (USPIO) and investigated in vitro in terms of morphology, size distribution, mechanical stability as well as ex vivo with magnetic resonance imaging (MRI) to assess their trackability and distribution. Generated 3D spheroids were stable, viable, maintained stem cell phenotype and were easily trackable and visualized via MRI. MSC 3D spheroids are suitable candidates for endovascular delivery approaches in the context of ischemic peripheral vascular pathologies.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Esferoides Celulares , Animales , Técnicas de Cultivo de Célula , Diferenciación Celular , Humanos , Isquemia/diagnóstico , Isquemia/etiología , Isquemia/metabolismo , Isquemia/terapia , Imagen por Resonancia Magnética , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/ultraestructura , Enfermedad Arterial Periférica/diagnóstico , Enfermedad Arterial Periférica/etiología , Enfermedad Arterial Periférica/metabolismo , Enfermedad Arterial Periférica/terapia , Esferoides Celulares/citología , Esferoides Celulares/ultraestructura , Coloración y Etiquetado
3.
Unfallchirurg ; 122(7): 573-577, 2019 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-30767026

RESUMEN

OBJECTIVE: The aim of this study was the elaboration of clinical symptoms and image findings in injuries of the wrist and ulnar-sided pain with accompanying damage to the articular disc and the triangular fibrocartilage complex (TFCC). MATERIAL AND METHODS: This article reports about a 26-year-old male patient who presented to the department of surgery of this hospital after repeated falls onto the right wrist. Following the latest fall there was persistent wrist pain and limited movement, especially in supination. The physical examination showed pressure pain above the ulnocarpal complex; however, under forced pronation and supination no pain in the ulnocarpal complex could be triggered. RESULTS: Due to the symptoms damage to the TFCC was suspected and a magnetic resonance imaging (MRI) examination of the wrist was carried out. A TFCC damage reaching as far as the dorsal radioulnar ligament involving the dorsal suspension was demarcated with dislocation and displacement of the disc. For further differentiation of the damaged structures arthrography was performed and contrast medium containing gadolinium was injected into the joint gap. The imaging showed avulsion of the dorsal triangular disc from the dorsal suspension with volar dislocation. Treatment was continued with an arthrotomy by the formation of an ulnar pedicled capsular flap, the luxated TFCC was repositioned, central frayed and torn parts were resected and smoothed. Finally, the TFCC was refixed with two 3/0 PDS U­sutures. CONCLUSION: Ulnar-sided wrist pain can be caused by a variety of clinical pathologies, so that often no diagnosis can be made based on clinical symptoms alone and an imaging method is required; however, for a clear assessment of the ligament or joint injuries an MRI is necessary. Particularly for the evaluation of the TFCC injuries MRI is a sensitive diagnostic method. In the decision making, especially when atypical injury patterns are present, an arthrography should be performed in addition to MRI to obtain the best possible information on the anatomical circumstances. KEY POINTS: In cases of injuries of the wrist and ulnar-sided pain collateral damage to the articular disc and the TFCC should always be considered and excluded when appropriate. A dislocation of the disc at the wrist is a rare consequence of trauma but should be considered in the differential diagnosis. In cases of unclear MRI results and complex injuries of the wrist or unclear symptoms, MR arthrography can be helpful.


Asunto(s)
Luxaciones Articulares/diagnóstico , Fibrocartílago Triangular , Traumatismos de la Muñeca/diagnóstico , Adulto , Artrografía , Humanos , Imagen por Resonancia Magnética , Masculino , Muñeca , Articulación de la Muñeca
4.
NMR Biomed ; 28(8): 1049-58, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26147577

RESUMEN

Direct stem cell therapies for functionally impaired tissue require a sufficient number of cells in the target region and a method for verifying the fate of the cells in the subsequent time course. In vivo MRI of iron labeled mesenchymal stem cells has been suggested to comply with these requirements. The study was conducted to evaluate proliferation, migration, differentiation and adhesion effects as well as the obtained iron load of an iron labeling strategy for mesenchymal stem cells. After injection into the porcine urethral sphincter, the labeled cells were monitored for up to six months using MRI. Mesenchymal stem cells were labeled with ferucarbotran (60/100/200 µg/mL) and ferumoxide (200 µg/mL) for the analysis of migration and viability. Phantom MR measurements were made to evaluate effects of iron labeling. For short and long term studies, the iron labeled cells were injected into the porcine urethral sphincter and monitored by MRI. High resolution anatomical images of the porcine urethral sphincter were applied for detection of the iron particles with a turbo-spin-echo sequence and a gradient-echo sequence with multiple TE values. The MR images were then compared with histological staining. The analysis of cell function after iron labeling showed no effects on proliferation or differentiation of the cells. Although the adherence increases with higher iron dose, the ability to migrate decreases as a presumed effect of iron labeling. The iron labeled mesenchymal stem cells were detectable in vivo in MRI and histological staining even six months after injection. Labeling with iron particles and subsequent evaluation with highly resolved three dimensional data acquisition allows sensitive tracking of cells injected into the porcine urethral sphincter for several months without substantial biological effects on mesenchymal stem cells.


Asunto(s)
Rastreo Celular/métodos , Hierro , Imagen por Resonancia Magnética/métodos , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/citología , Uretra/citología , Animales , Movimiento Celular/fisiología , Supervivencia Celular/fisiología , Medios de Contraste , Endoscopía/métodos , Células Madre Mesenquimatosas/fisiología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Coloración y Etiquetado/métodos , Porcinos , Uretra/cirugía
5.
J Vasc Interv Radiol ; 26(9): 1388-95, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26169455

RESUMEN

PURPOSE: To compare the effects of sirolimus, paclitaxel, and combretastatin A4 (CA4) on regulatory proteins of the cell cycle in proliferating smooth muscle cells (SMCs). MATERIALS AND METHODS: Human aortic SMCs were treated with sirolimus, paclitaxel, and CA4 at 5 × 10(-9) mol/L. After 1 day, half of the cells were harvested (DAY1 group). The treatment medium of the other half was replaced with culture medium on day 4, and those cells were harvested on day 5 (DAY5 group). Cyclins D1, D2, E, and A and cyclin-dependent kinase (CDK) inhibitors p16, p21, and p27 were detected by Western blot technique. Quantification was performed by scanning densitometry of the specific bands. RESULTS: In the DAY1 group, treatment with sirolimus resulted in decreased intracellular levels of cyclins D2 and A (P < .05). Increased D cyclins and reduced levels of cyclins E and A (P < .05) in the DAY5 group indicated a permanent G1/S block by sirolimus. Paclitaxel led to only slight alterations of cyclin and CDK inhibitor expression (P > .05). In the DAY1 group, CA4 decreased intracellular levels of cyclins D2, E, and A (P < .05). Despite recovery effects in the DAY5 group (increase of cyclins D1, D2, and A compared with DAY1 group; P < .05), the upregulation of the CDK inhibitor p21, increased D cyclins, and decreased cyclins E and A (P < .05) are compatible with a G1 arrest. CONCLUSIONS: CA4 is a stronger inhibitor of the SMC cycle than sirolimus or paclitaxel and may represent an alternative for drug-eluting stents in atherosclerotic luminal stenosis. The effect of CA4 on neointima formation should be evaluated further.


Asunto(s)
Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/efectos de los fármacos , Neointima/prevención & control , Paclitaxel/administración & dosificación , Sirolimus/administración & dosificación , Estilbenos/administración & dosificación , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Humanos , Neointima/patología , Resultado del Tratamiento , Moduladores de Tubulina/administración & dosificación
6.
J Vasc Interv Radiol ; 26(11): 1728-34.e1-3, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26233838

RESUMEN

PURPOSE: To evaluate the distribution of superparamagnetic iron oxide (SPIO)-labeled cells in a perfused segment of a porcine artery and to estimate the number of adherent cells by means of magnetic resonance (MR) imaging. MATERIALS AND METHODS: Six vessel specimens (diameters between 0.8 and 1.2 cm) were placed in a bioreactor system, and 2 × 10(4) to 1 × 10(6) SPIO-labeled endothelial colony-forming cells were injected into the artery within the perfused reactor. The area of resulting signal extinctions at the inner wall of the vessels was quantified on MR images by using a high-resolution T2*-weighted sequence with a slice-by-slice approach. After imaging, the labeled cells were quantified histologically. RESULTS: The total iron load of each cell was 56.5 pg ± 14.4. In the applied range of 2 × 10(4) to 1 × 10(6) cells per vessel, the area of iron-induced signal extinction at the vessel wall on T2*-weighted imaging corresponded to the histologically detected cell number (r = 0.98, P < .001). CONCLUSIONS: A correlation between the area of signal extinction and the number of labeled cells at the vessel wall was found. This might help to evaluate dose rates in further clinical applications of intravascular cell-based therapies.


Asunto(s)
Adhesión Celular/fisiología , Rastreo Celular/métodos , Dextranos , Imagen por Resonancia Magnética Intervencional/métodos , Nanopartículas de Magnetita , Arterias Torácicas/citología , Arterias Torácicas/fisiología , Animales , Células Cultivadas , Medios de Contraste , Humanos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Coloración y Etiquetado , Estadística como Asunto , Trasplante de Células Madre/métodos , Células Madre , Porcinos , Arterias Torácicas/cirugía
7.
CVIR Endovasc ; 7(1): 53, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976091

RESUMEN

BACKGROUND: The Viabahn endoprosthesis has become a vital option for endovascular therapy, yet there is limited long-term data on its effectiveness for peripheral aneurysm repair. This study aimed to evaluate the safety, technical and clinical success, and long-term patency of the Viabahn endoprosthesis for treating femoropopliteal aneurysms. METHODS: This retrospective tertiary single-center study analyzed patients who underwent a Viabahn endoprosthesis procedure for femoropopliteal aneurysm repair from 2010 to 2020. Intraoperative complications, technical and clinical success rates, and major adverse events (MAE, including acute thrombotic occlusion, major amputation, myocardial infarction, and device- or procedure-related death) at 30 days were assessed. Incidence of clinically-driven target lesion revascularisation (cdTLR) was noted. Patency rates were evaluated by Kaplan-Meier analysis. RESULTS: Among 19 patients (mean age, 72 ± 12 years; 18 male, 1 female) who underwent aneurysm repair using the Viabahn endoprosthesis, there were no intraoperative adverse events, with 100% technical and clinical success rates. At the 30-day mark, all patients (19/19, 100%) were free of MAE. The median follow-up duration was 1,009 days [IQR, 462-1,466]. Popliteal stent graft occlusion occurred in 2/19 patients (10.5%) after 27 and 45 months, respectively. Consequently, the primary patency rates were 100%, 90%, 74% at 12, 24, and 36-72 months, respectively. Endovascular cdTLR was successful in both cases, resulting in sustained secondary patency at 100%. CONCLUSION: The use of Viabahn endoprostheses for femoropopliteal aneurysm repair demonstrated technical and clinical success rates of 100%, a 0% 30-day MAE rate, and excellent long-term patency.

8.
J Clin Med ; 13(10)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38792455

RESUMEN

Background/Objectives: To assess free-breathing, dynamic radial magnetic resonance angiography (MRA) for detecting endoleaks post-endovascular aortic repair (EVAR) in cases with inconclusive computed tomography angiography (CTA). Methods: This prospective single-center study included 17 participants (mean age, 70 ± 9 years; 13 males) who underwent dynamic radial MRI (Golden-angle RAdial Sparse Parallel-Volumetric Interpolated BrEath-hold, GRASP-VIBE) after inconclusive multiphasic CT for the presence of endoleaks during the follow-up of EVAR-treated abdominal aortic aneurysms. CT and MRI datasets were independently assessed by two radiologists for image quality, diagnostic confidence, and the presence/type of endoleak. Statistical analyses included interrater and intermethod agreement, and diagnostic performance (sensitivity, specificity, area under the curve (AUC)). Results: Subjective image analysis demonstrated good image quality and interrater agreement (k ≥ 0.6) for both modalities, while diagnostic confidence was significantly higher in MRA (p = 0.03). There was significantly improved accuracy for detecting type II endoleaks on MRA (AUC 0.97 [95% CI: 0.87, 1.0]) compared to CTA (AUC 0.66 [95% CI: 0.41, 0.91]; p = 0.03). Although MRA demonstrated higher values for sensitivity, specificity, AUC, and interrater agreement, none of the other types nor the overall detection rate for endoleaks showed differences in the diagnostic performance over CT (p ≥ 0.12). CTA and MRA revealed slight to moderate intermethod concordance in endoleak detection (k = 0.3-0.64). Conclusions: The GRASP-VIBE MRA characterized by high spatial and temporal resolution demonstrates clinical feasibility with good image quality and superior diagnostic confidence. It notably enhances diagnostic performance in detecting and classifying endoleaks, particularly type II, compared to traditional multiphase CTA with inconclusive findings.

9.
CVIR Endovasc ; 7(1): 23, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38416319

RESUMEN

BACKGROUND: The Viabahn stent graft has emerged as an integral tool for managing vascular diseases, but there is limited long-term data on its performance in emergency endovascular treatment. This study aimed to assess safety, technical success, and long-term efficacy of the Viabahn stent graft in emergency treatment of arterial injury. METHODS: We conducted a retrospective single tertiary centre analysis of patients who underwent Viabahn emergency arterial injury treatment between 2015 and 2020. Indication, intraoperative complications, technical and clinical success, and major adverse events at 30 days were evaluated. Secondary efficacy endpoints were the primary and secondary patency rates assessed by Kaplan-Meier analysis. RESULTS: Forty patients (71 ± 13 years, 19 women) were analyzed. Indications for Viabahn emergency treatment were extravasation (65.0%), arterio-venous fistula (22.5%), pseudoaneurysm (10.0%), and arterio-ureteral fistula (2.5%). No intraoperative adverse events occurred, technical and clinical success rates were 100%. One acute stent graft occlusion occurred in the popliteal artery on day 9, resulting in a 30-day device-related major-adverse-event rate of 2.5%. Median follow-up was 402 days [IQR, 43-1093]. Primary patency rate was 97% (95% CI: 94-100) in year 1, and 92% (95% CI: 86-98) from years 2 to 6. One stent graft occlusion occurred in the external iliac artery at 18 months; successful revascularization resulted in secondary patency rates of 97% (95% CI: 94-100) from years 1 to 6. CONCLUSION: Using Viabahn stent graft in emergency arterial injury treatment had 100% technical and clinical success rates, a low 30-day major-adverse-event rate of 2.5%, and excellent long-term patency rates.

10.
Quant Imaging Med Surg ; 14(10): 7420-7432, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39429596

RESUMEN

Background: Time-resolved angiography with interleaved stochastic trajectories (TWIST) magnetic resonance angiography (MRA) may obscure smaller vessels and is highly susceptibility to motion artifacts, potentially reducing endoleak detection accuracy after endovascular aortic repair (EVAR). The novel golden-angle radial sparse parallel (GRASP) sequence enhances spatial and temporal resolution with continuous, motion-robust datasets, showing promise for accurate endoleak detection post-EVAR. This study aimed to compare the diagnostic effectiveness of contrast-enhanced compressed-sensing radial GRASP-volume interpolated breath-hold examination (VIBE) sequence with standard contrast-enhanced dynamic TWIST-VIBE sequence in patients with inconclusive computed tomography angiography (CTA) findings regarding endoleak after EVAR. Methods: This single-center prospective study consecutively enrolled adults with inconclusive findings regarding the presence or type of endoleak in multiphasic CTA following EVAR for abdominal aortic aneurysms. Participants underwent contrast-enhanced MRA, acquiring dynamic TWIST-VIBE and GRASP-VIBE sequences. Two independent radiologists assessed the datasets for image quality, diagnostic confidence, and the presence and type of endoleak. Additionally, quantitative assessments with signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) were performed. Statistical analyses included interrater and intermethod agreement, and diagnostic performance testing. Results: Twenty participants (mean age, 72±9 years; 13 males) were included. GRASP-VIBE demonstrated superior image quality over TWIST-VIBE sequence with predominantly absent motion artifacts and increased diagnostic confidence (all P<0.001). Diagnostic performance significantly improved for detecting type II endoleaks in GRASP-VIBE compared to TWIST-VIBE scans [area under the curve (AUC): 0.96 vs. 0.73; P=0.04]. Diagnostic accuracy improved with GRASP-VIBE for overall (AUC: 0.94 vs. 0.79) and endoleak type I detection (AUC: 1.0 vs. 0.90), however, not significantly (P≥0.05). TWIST-VIBE sequences demonstrated significantly higher SNR for measurements in the clotted aneurysm sac (P=0.01). No significant differences were observed in CNR for the aorta and any aneurysm sacs across the compared imaging sequences. Conclusions: Compressed-sensing dynamic GRASP-VIBE sequence, with its superior image quality, diagnostic confidence, and performance, may be preferred over standard TWIST-VIBE sequence in inconclusive endoleak cases.

11.
J Endovasc Ther ; 20(5): 699-706, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24093324

RESUMEN

PURPOSE: To present the 12-month results of a trial investigating the effects of dual antiplatelet therapy on target lesion revascularization (TLR) after balloon angioplasty ± stenting in the femoropopliteal segment. METHODS: A prospective, randomized, single-center, double-blinded and placebo-controlled clinical trial randomly assigned 40 patients to receive pre- and postinterventional therapy with aspirin and clopidogrel. Another 40 patients received the same doses of aspirin and placebo instead of clopidogrel. Clopidogrel and placebo were stopped after 6 months, and patients remained on aspirin only. At 12 months after the intervention, 36 clopidogrel patients and 37 placebo patients were reevaluated. RESULTS: At 6 months, clopidogrel patients had significantly lower rates of TLR compared to placebo patients [2 (5%) vs. 8 (20%), p=0.04]. After stopping clopidogrel/placebo after 6 months, there was no significant difference in TLR at 12 months after treatment [9 (25%) clopidogrel vs. 12 (32.4%) placebo, p=0.35]. Mortality was 0 vs. 1 in the placebo group at 6 months (p=0.32) and 0 vs. 3 at 12 months (p=0.08). CONCLUSION: In contrast to the first report of a reduction in the TLR at 6 months, this advantage of dual antiplatelet therapy does not persist after stopping clopidogrel. Prolonged dual therapy (>6 months) should be considered in patients who are at high risk for restenosis.


Asunto(s)
Angioplastia de Balón , Aspirina/uso terapéutico , Enfermedad Arterial Periférica/terapia , Inhibidores de Agregación Plaquetaria/uso terapéutico , Ticlopidina/análogos & derivados , Anciano , Anciano de 80 o más Años , Angioplastia de Balón/efectos adversos , Angioplastia de Balón/instrumentación , Aspirina/efectos adversos , Clopidogrel , Método Doble Ciego , Quimioterapia Combinada , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/diagnóstico , Inhibidores de Agregación Plaquetaria/efectos adversos , Estudios Prospectivos , Recurrencia , Stents , Ticlopidina/efectos adversos , Ticlopidina/uso terapéutico , Factores de Tiempo , Resultado del Tratamiento
12.
Eur Radiol ; 22(9): 1998-2006, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22569995

RESUMEN

OBJECTIVES: To investigate the influence of dual antiplatelet therapy vs. aspirin alone on local platelet activation and clinical endpoints in patients with PAD treated with endovascular therapy. METHODS: Patients received either 500 mg aspirin and 300 mg clopidogrel before intervention followed by a daily dose of 100 mg aspirin and 75 mg clopidogrel for 6 months, or the same doses of aspirin plus placebo instead of clopidogrel. Primary endpoints were local concentrations of platelet activation markers ß-thromboglobulin and CD40L, and the rate of patient's resistant to clopidogrel. Secondary endpoints included the clinical development 6 months after the intervention. RESULTS: Eighty patients, 40 in each group, were enrolled. The median peri-interventional concentration of ß-TG was 224.5 vs. 365.5 (P = 0.03) in the clopidogrel and placebo group. The concentration of CD40L was 127 and 206.5 (P = 0.05). Thirty per cent of patients who had received clopidogrel were resistant. Two clopidogrel and eight placebo patients required TLR (P = 0.04). The clopidogrel patients who needed revascularisation were both resistant to clopidogrel. Minor bleeding complications occurred in one clopidogrel and two placebo patients. CONCLUSION: Dual antiplatetet therapy reduces peri-interventional platelet activation and improves functional outcome without higher bleeding complications. An individual tailored dual antiplatelet therapy seems desirable for endovascularly treated patients with PAD.


Asunto(s)
Angioplastia/efectos adversos , Aspirina/uso terapéutico , Enfermedad Arterial Periférica/cirugía , Inhibidores de Agregación Plaquetaria/uso terapéutico , Trombosis/tratamiento farmacológico , Trombosis/etiología , Anciano , Método Doble Ciego , Femenino , Humanos , Masculino , Enfermedad Arterial Periférica/complicaciones , Resultado del Tratamiento
13.
AJR Am J Roentgenol ; 198(4): 946-54, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22451565

RESUMEN

OBJECTIVE: The objective of this study was to compare the performance and radiation doses of a flat-panel detector (FPD) angiography machine with an image intensifier (II) angiography machine. MATERIALS AND METHODS: Images of four nitinol stents (Sinus-SuperFlex, SMART, Luminexx, and Zilver stents) in a phantom of a human pelvis were acquired on an FPD system (Axiom Artis) and an II system (Fluorospot TOP) using the following modes: spot-film, continuous fluoroscopy (4, 7.5, 15, and 30 pulses/s), and three amplification modes. Objective stent detection rates and subjective radiopacity scores (scale: 0 [not visible] to 4 [excellent visibility]) were calculated. The radiation doses evaluated by the respective machines were compared. RESULTS: Over all modes and stents, the mean objective correct stent detection rates and mean subjective radiopacity scores were 89.49% and 1.81, respectively, for the Axiom Artis and 91.00% and 2.26 for the Fluorospot TOP. The stent detection rates over all modes for the SMART and Luminexx stents were better using the Axiom Artis machine (97.61% vs 93.55% and 98.28% vs 90.41%, respectively) and those for the Sinus-SuperFlex and Zilver stents were better using the Fluorospot TOP machine (90.83% vs 83.56% and 89.29% vs 80.50%). The subjective radiopacity scores of stent visibility were worse for the Axiom Artis than the Fluorospot TOP for all stents except the Luminexx stent (mean score, 2.34 vs 2.21, respectively). The objective stent detection rates and subjective radiopacity scores improved using the spot-film mode and with raising amplification, whereas increases in the fluoroscopy pulsing frequency did not improve stent detection rates or radiopacity scores for either machine. The radiation doses at continuous fluoroscopy were approximately 90% higher for the Axiom Artis than for the Fluorospot TOP (2.60 vs 1.41 µGy/m(2) at 30 pulses/s, respectively). CONCLUSION: The objective correct stent detection rates were similar for both machines with differences in detection for the respective stents. The subjective radiopacity scores were almost always better for the Fluorospot TOP machine. Also, the Axiom Artis machine generated approximately 90% higher radiation doses in fluoroscopy. For both machines, using a higher fluoroscopy pulsing frequency had no positive effect on objective correct stent detection rates or subjective radiopacity scores.


Asunto(s)
Angiografía/instrumentación , Pelvis/diagnóstico por imagen , Stents , Pantallas Intensificadoras de Rayos X , Aleaciones , Fluoroscopía/instrumentación , Humanos , Fantasmas de Imagen , Diseño de Prótesis , Dosis de Radiación , Estadísticas no Paramétricas
14.
Acta Radiol ; 53(9): 1020-5, 2012 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-22969090

RESUMEN

BACKGROUND: Sufficient radiopacity of stents is a prerequisite for safe interventions and minimization of the radiation dose for the patient and the interventionist. Modern nitinol stents are considered less radiopaque compared to formerly used stents. PURPOSE: To evaluate the objective detection rate (ODR) and the subjective radiopacity score (SRS) of four self-expanding nitinol stents with their markers on a phantom human pelvis. MATERIAL AND METHODS: We evaluated the ODR (as a percentage of correctly identified stents) and the SRS (on a scale from 0 = not visible to 4 = excellent visibility) for four self-expanding nitinol stents (SinusSuperflex, SMART, Luminexx, Zilver) with 8 mm diameter and 40 mm length. Stents were placed on a phantom human pelvis and images of the stents were taken in four different positions (right and left lumbosacral joint and near the right and left limbus acetabuli) using the following modes: spotfilm, pulsed fluoroscopy (4, 7.5, 15, and 30 pulses/min) and at three different digital magnification modes. Dose area products (DAPs) were assessed. RESULTS: ODR and SRS, respectively, were significantly increased for the SMART stent compared to all other tested stents (P < 0.05): SMART 93.53% and 2.43, SinusSuperflex 90.81% and 2.21, Luminexx 90.39% and 2.20, and Zilver 89.28% and 2.21. ODR was significantly reduced in position 3 where the bone overlap was more pronounced for all stents (detection rates 77.14-79.56%). An increase in magnification significantly improved the ODR and SRS for all stents (70.33-99.25% and 1.07-3.28, respectively, P < 0.05). Increased pulsing frequency did not improve the ODR of the various stents but did increase the DAP. CONCLUSION: The SMART stent had the best overall performance. In the presence of bone overlap, all self-expanding nitinol stents had poor results. Increased pulsing frequency did not improve ODR or SRS but did increase the DAP. Use of digital magnification modes had no effect on DAP increasing ODR and SRS.


Asunto(s)
Aleaciones , Angioplastia/instrumentación , Fluoroscopía , Humanos , Técnicas In Vitro , Pelvis , Fantasmas de Imagen , Diseño de Prótesis , Dosis de Radiación , Estadísticas no Paramétricas , Stents
15.
J Vasc Interv Radiol ; 22(5): 623-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21414804

RESUMEN

PURPOSE: Restenosis is still one of the major limitations after angioplasty. A therapeutic treatment combining ß-irradiation and pharmacologic cyclooxygenase-2 inhibition was employed to study the impact on vascular smooth muscle cells (SMCs). MATERIALS AND METHODS: The effects of meclofenamic acid in combination with yttrium-90 ((90)Y) on cell growth, clonogenic activity, cell migration, and cell cycle distribution of human aortic SMCs were investigated. Treatment was sustained over a period of 4 days and recovery of cells was determined until day 20 after initiation. The hypothesis was that there is no difference between control and treated groups. RESULTS: A dose-dependent growth inhibition was observed in single and combined treatment groups for meclofenamic acid and ß-irradiation. Cumulative radiation dosage of 8 Gy completely inhibited colony formation. This was also observed for 200 µM meclofenamic acid alone or in combination with minor ß-irradiation dosages. Results of the migration tests showed also a dose dependency with additive effects of combined therapy. Meclofenamic acid 200 µM alone and with cumulative ß-irradiation dosages resulted in an increased G2/M-phase share. CONCLUSIONS: Incubating human SMCs with meclofenamic acid and (90)Y for a period of 4 d (ie, 1.5 half-life times) resulted in an effective inhibition of smooth muscle cell proliferation, colony formation, and migration.


Asunto(s)
Arteriopatías Oclusivas/prevención & control , Braquiterapia , Inhibidores de la Ciclooxigenasa 2/farmacología , Ácido Meclofenámico/farmacología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/efectos de la radiación , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/efectos de la radiación , Radioisótopos de Itrio , Angioplastia de Balón/efectos adversos , Arteriopatías Oclusivas/etiología , Arteriopatías Oclusivas/patología , Ciclo Celular/efectos de los fármacos , Ciclo Celular/efectos de la radiación , Movimiento Celular/efectos de los fármacos , Movimiento Celular/efectos de la radiación , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Células Cultivadas , Terapia Combinada , Constricción Patológica , Relación Dosis-Respuesta a Droga , Relación Dosis-Respuesta en la Radiación , Humanos , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/patología , Prevención Secundaria , Factores de Tiempo
16.
Hamostaseologie ; 41(5): 400-402, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34492713

RESUMEN

In this case report we present a previously healthy 21-year-old male with extensive thromboembolism in the setting of asymptomatic COVID-19 infection and heterozygous factor V Leiden mutation with no additional thrombophilic risk factors.


Asunto(s)
COVID-19/complicaciones , Factor V/genética , SARS-CoV-2 , Tromboembolia/complicaciones , Tromboembolia/genética , Infecciones Asintomáticas , COVID-19/diagnóstico , COVID-19/diagnóstico por imagen , Angiografía por Tomografía Computarizada , Heterocigoto , Humanos , Masculino , Tromboembolia/terapia , Adulto Joven
17.
Eur J Radiol ; 84(11): 2173-80, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26226916

RESUMEN

Rationale of this study was to evaluate whether unfolded rib images enhance time efficiency in detection of rib fractures and time efficiency in patients with acute thoracic trauma. 51 subsequent patients with thoracic trauma underwent 64-slice computed tomography. 1mm thick axial slices were reformatted using a commercially available post-processing software application generating rotatable unfolded rib images. Diagnostic accuracy was evaluated by 3 readers and compared to multiplanar reformations of the original CT images. Reformation and evaluation times were recorded. 116 rib fractures were detected. The multiplanar reformation analysis yielded a sensitivity of 87.9%/93.9%/79.7% with a specificity of 97%/97%/82.2%, whilst the unfolded rib image analysis yielded a sensitivity of 94.8%/94.8%/92.2% and a specificity of 85.2/87.8%/82.4 (p=0.06/0.8/0.04) with high inter-observer agreement (k=0.79-0.85). The mean reading time for the multiplanar reformations was significantly longer (reader 1: 103.7 ± 27.1s/reader 2: 81.8 ± 40.6s/reader 3: 154.3 ± 39.2s) than the evaluation of the unfolded rib images (19.4 ± 4.9s/26.9 ± 15.0s/49.9 ± 18.7s; p<0.01). Concluding, the unfolded rib display reduces reading time for detection of rib fractures in acute thoracic trauma patients significantly and does not compromise the diagnostic accuracy significantly in experienced radiologists. However, unexperienced readers may profit from use of this display.


Asunto(s)
Tórax Paradójico/diagnóstico por imagen , Fracturas de las Costillas/diagnóstico por imagen , Costillas/patología , Traumatismos Torácicos/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Intensificación de Imagen Radiográfica , Interpretación de Imagen Radiográfica Asistida por Computador , Reproducibilidad de los Resultados , Costillas/lesiones , Tomografía Computarizada por Rayos X/métodos
18.
Eur J Radiol ; 82(12): 2258-64, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24029160

RESUMEN

PURPOSE: The portosystemic pressure gradient is an important factor defining prognosis in hepatic disease. However, noninvasive prediction of the gradient and the possible reduction by establishment of a TIPSS is challenging. A cohort of patients receiving TIPSS was evaluated with regard to imaging features of collaterals in cross-sectional imaging and the achievable reduction of the pressure gradient by establishment of a TIPSS. METHODS: In this study 70 consecutive patients with cirrhotic liver disease were retrospectively evaluated. Patients received either CT or MR imaging before invasive pressure measurement during TIPSS procedure. Images were evaluated with regard to esophageal and fundus varices, splenorenal collaterals, short gastric vein and paraumbilical vein. Results were correlated with Child stage, portosystemic pressure gradient and post-TIPSS reduction of the pressure gradient. RESULTS: In 55 of the 70 patients TIPSS reduced the pressure gradient to less than 12 mmHg. The pre-interventional pressure and the pressure reduction were not significantly different between Child stages. Imaging features of varices and portosystemic collaterals did not show significant differences. The only parameter with a significant predictive value for the reduction of the pressure gradient was the pre-TIPSS pressure gradient (r = 0.8, p<0.001). CONCLUSIONS: TIPSS allows a reliable reduction of the pressure gradient even at high pre-interventional pressure levels and a high collateral presence. In patients receiving TIPSS the presence and the characteristics of the collateral vessels seem to be too variable to draw reliable conclusions concerning the portosystemic pressure gradient.


Asunto(s)
Determinación de la Presión Sanguínea/métodos , Hipertensión Portal/diagnóstico , Hipertensión Portal/etiología , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Presión Sanguínea , Femenino , Humanos , Hipertensión Portal/fisiopatología , Cirrosis Hepática/fisiopatología , Masculino , Persona de Mediana Edad , Derivación Portosistémica Intrahepática Transyugular , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Resultado del Tratamiento
19.
Cardiovasc Intervent Radiol ; 36(3): 756-63, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23435745

RESUMEN

PURPOSE: The efficacy of drug-eluting balloons has been demonstrated in clinical trials. The drug predominantly used is paclitaxel because of its lipophilic properties and the rapid onset of action. The aim of the investigation was to evaluate the feasibility and efficacy of an alternative balloon coating with rapamycin that can be applied on site. METHODS: The balloon coating (3.0/18 and 3.0/12 mm, Cathy No. 4, Translumina GmbH) with rapamycin was conducted with a coating machine (Translumina GmbH). Concentrations were 2, 2 × 2, 3, and 4 %. Measurements regarding the amount of substance released to the vessel wall were carried out on explanted porcine coronaries by means of ultraviolet and visible-light spectroscopy. Inflation time varied between 30 and 120 s. The biological effect of the coating was evaluated in a porcine peripheral overstretch and stent implantation model. RESULTS: The amount of rapamycin on the balloon surface ranged from 558 ± 108 µg for the 2 % solution to 1,441 ± 228 µg in the 4 % solution. An amount of 95 ± 63-193 ± 113 µg was released into the vessel wall. The quantitative measurements of the angiographic examinations 4 weeks after treatment revealed a reduction of diameter stenosis from 20.6 ± 17.4 % in the control group to 11.6 ± 5.5 % in the drug-eluting balloon group. CONCLUSION: A balloon coating with rapamycin omitting an excipient is possible with a dose-adjustable coating machine. However, the biological effects are moderate, which make further optimization of the coating process and evaluation of appropriate excipients necessary.


Asunto(s)
Angioplastia Coronaria con Balón , Sistemas de Liberación de Medicamentos , Sirolimus/farmacología , Animales , Angiografía Coronaria , Estudios de Factibilidad , Inmunohistoquímica , Microscopía Electrónica de Rastreo , Propiedades de Superficie , Porcinos
20.
Cardiovasc Intervent Radiol ; 35(6): 1439-47, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22159909

RESUMEN

PURPOSE: To evaluate in vivo the role of RAGE (receptor for advanced glycated end products) in the development of restenosis and neointimal proliferation in RAGE-deficient knockout (KO) mice compared with wild-type (WT) mice in an animal model. MATERIALS AND METHODS: Sixteen WT and 15 RAGE-deficient mice underwent microvascular denudation of the common femoral artery under general anaesthesia. Contralateral arteries underwent a sham operation and served as controls. Four weeks after the intervention, all animals were killed, and paraformaldehyde-fixed specimens of the femoral artery were analysed with different stains (hematoxylin and eosin and Elastica van Gieson) and several different types of immunostaining (proliferating cell nuclear antigen, α-actin, collagen, von Willebrand factor, RAGE). Luminal area, area of the neointima, and area of the media were measured in all specimens. In addition, colony-formation assays were performed, and collagen production by WT smooth muscle cells (SMCs) and RAGE-KO SMCs was determined. For statistical analysis, P < 0.05 was considered statistically significant. RESULTS: Four weeks after denudation, WT mice showed a 49.6% loss of luminal area compared with 14.9% loss of luminal area in RAGE-deficient mice (sham = 0% loss) (P < 0.001). The neointima was 18.2 (*1000 µm(2) [n = 15) in the WT group compared with only 8.4 (*1000 µm(2) [n = 16]) in the RAGE-KO group. RAGE-KO SMCs showed significantly decreased proliferation activity and production of extracellular matrix protein. CONCLUSION: RAGE may be shown to play a considerable role in the formation of neointima leading to restenosis after vascular injury.


Asunto(s)
Arteria Femoral/cirugía , Neointima , Receptores Inmunológicos/metabolismo , Actinas/metabolismo , Animales , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Ratones , Ratones Noqueados , Antígeno Nuclear de Célula en Proliferación/metabolismo , ARN Mensajero/análisis , Receptor para Productos Finales de Glicación Avanzada , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de von Willebrand/metabolismo
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