- Abstract: To assess the effectiveness of self-expanding, cobalt-alloy stents in the treatment of aneurysms in a canine model and to observe the pattern of blood flow and formation of fibrotic scar tissue. Porous metallic stents were endovascularly placed across the necks of experimentally created side aneurysms in the carotid arteries of three dogs; aneurysms were also created in the opposite carotid arteries in these animals to serve as controls. Before stent placement, angiography of the carotid... Show More
- Abstract: To determine the efficacy of porous metallic stents in the treatment of experimentally created carotid-jugular fistulas. Carotid-jugular fistulas were constructed surgically in five mongrel dogs. Porous metallic stents were placed endovascularly across the fistula holes within the carotid artery; carotid angiography was performed before, immediately after, and 1 and 2 months after stent placement. The fistula specimens were resected 2 months after stent placement; gross and light microscopic... Show More
- Abstract: To determine the efficacy of silicone-covered metallic stents in the treatment of experimentally created carotid-jugular fistulas. Carotid-jugular fistulas were surgically constructed in six mongrel dogs. Silicone-coated, self-expanding metallic stents were placed across the fistula holes within the carotid artery, and carotid angiography was performed before, immediately after, and 4 and 8 weeks after stent placement. Fistula specimens were resected 2 months after stent placement and... Show More
- Abstract: Our experimental study in dogs suggests that laser-activated detachable coil devices show promise in the embolization of carotid aneurysms, allowing the interventionalist greater control than possible with nonretractable coil systems and permitting detachment of the coil from the wire in seconds.
- Abstract: Carotid fusiform aneurysms are most commonly treated with occlusion of the parent vessel. The purpose of our study was to assess the effectiveness of self-expanding, cobalt-alloy stents in the ablation of experimental fusiform aneurysms with preservation of the parent vessel in a carotid artery model. Porous metallic stents were placed endovascularly along the lengths of experimentally created fusiform aneurysms in the carotid arteries of dogs; aneurysms were also created in the animals'... Show More
Publications citing this author (241)
[Show abstract] [Hide abstract] ABSTRACT: Introduction: Refinements in endovascular technology have revolutionized the treatment of intracranial aneurysms (IAs) with the development of flow-diversion technology. The first generation of the Pipelin Embolization Device (PED) has demonstrated its safety and efficacy. However, the deployment technique was a difficult task that often led to complex maneuvers. The Pipeline Flex Embolization Device (PED Flex) is the second generation and its introduction has arrived with high expectations due to a completely redesigned delivery system that intends to overcome deployment difficulties seen in the previous generation. Areas covered: Preclinical studies, mechanism of action of flow-diverters, technical aspects and deployment system of the PED Flex, and clinical outcomes with both PED generations. Expert commentary: Flow diversion has allowed us to treat lesions that would be otherwise challenging for surgical clipping or unsuitable for other endosaccular strategies. Although the experience with PED Flex is limited, initial results suggest its safety and short-term efficacy.
- The observation that intracranial stents were able to modify flow dynamics inside the aneurysm gave rise to the hypothesis that disrupting the inflow to the aneurysm would lead to thrombus formation and subsequently aneurysm occlusion without endosaccular manipulation. In vitro and in vivo animal experimentation confirmed the theoretical concept that reduction of inflow, velocity, and turbulence contributed to progressive thrombosis of sidewall aneurysms[29,30].
- The asymmetry parameter β is defined as β = D 2 /D 1 , where D 1 is the maximum height above the center line, and D 2 is the maximum height below the center line. The orifice length L 2 is 20 mm, which is close to the value observed in clinical experiments. The length and diameter of the stent are 25 mm and 0.1 mm, respectively, we note that these values are also adopted in the previous work, in which steady blood flows in the saccular aneurysms were investigated, while unlike the previous work, here we consider the pulsatile flows in the fusiformaneurysms.
[Show abstract] [Hide abstract] ABSTRACT: Background The combination of biliary stent with photodynamic and chemotherapy seemed to be a beneficial palliative treatment of unresectable cholangiocarcinoma. However, by intravenous delivery to the target tumor the distribution of the drug had its limitations and caused serious side effect on non-target organs. Therefore, in this study, we are going to develop a localized eluting stent, named PDT-chemo stent, covered with gemcitabine (GEM) and hematoporphyrin (HP). Methods The prototype of PDT-chemo stent was made through electrospinning and electrospraying dual-processes with an electrical charge to cover the stent with a drug-storing membrane from polymer liquid. The design of prototype used PU as the material of the backing layer, and PCL/PEG blends in different molar ratio of 9:1 and of 1:4 were used in two drug-storing layers with GEM and HP loaded respectively. Results The optical microscopy revealed that the backing layer was formed in fine fibers from electrospinning, while drug-storing layers, attributed to the droplets from electrospraying process. The covered membrane, the morphology of which was observed by scanning electron microscopy (SEM), covered the stent surface homogeneously without crack appearances. The GEM had almost 100% of electrosprayed efficiency than 70% HP loaded on the covered membrane due to the different solubility of drug in PEG/PCL blends. Drug release study confirmed the two-phased drug release pattern by regulating in different molar ratio of PEG/PCL blends polymer. Conclusions The result proves that the PDT-chemo stent is composed of a first burst-releasing phase from HP and a later slow-releasing phase from GEM eluting. This two-phase of drug eluting stent may provide a new prospect of localized and controlled release treatment for cholangiocarcinoma disease.
- Silicone, PTFE, and PU) have been approved by US Food and Drug Administration (FDA) as the covered membrane on the stent . Silicone was reported to cause the acute inflammation to the surrounding tissue . The PTFE, however, could not be dissolved into any solvent .