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Beijing Da Xue Xue Bao. Yi Xue Ban =... Dec 2018To prepare ion exchange doxorubicin-loaded poly (acrylic acid) microspheres (DPMs) and evaluate the properties of these chemoembolic agents.
OBJECTIVE
To prepare ion exchange doxorubicin-loaded poly (acrylic acid) microspheres (DPMs) and evaluate the properties of these chemoembolic agents.
METHODS
Poly (acrylic acid) microspheres (PMs) without drug were prepared by inverse suspension polymerization method and then doxorubicin was loaded by ion exchange mechanism to prepare DPMs. Optical microscope was used to investigate the morphology and particle size distribution of PMs and DPMs; fluorescence microscope and confocal microscope were used to observe the distribution of doxorubicin after drug loading. Elasticities of both the microspheres were evaluated by texture analyzer. High performance liquid chromatography (HPLC) method was established to determine the drug loading behavior of PMs and releasing behavior of DPMs. The in vivo embolic property was evaluated by embolizing the hepatic artery of a rabbit with 0.1 mL of DPMs.
RESULTS
PMs and DPMs were both spherical in shape, smooth in surface and dispersed well. Doxorubicin was mainly in the outer area inside of DPMs and distributed evenly. The average particle size of PMs and DPMs were (283±136) μm and (248±149) μm, respectively. PMs and DPMs both had good compression ability with the Young's modulus of (62.63±1.65) kPa and (93.94±1.10) kPa separately. PMs reached the drug loading balance at 12 h, and the entrapment efficiency was greater than 99%. Drug loading of PMs in doxorubicin solution at the concentration of 5.0 g/L and 12.5 g/L was (19.78±0.27) g/L and (49.45±0.37) g/L, respectively. Doxorubicin released slowly from DPMs in PBS and the accumulative release percentages of DPMs with corresponding drug loading were 6.82%±0.02% and 2.83%±0.10% after 24 h, respectively. Arterial angiograms showed that the hepatic artery of the rabbit was successfully embolized with DPMs.
CONCLUSION
DPMs with good performance of loading doxorubicin could be a potential embolic agent for transcatheter arterial chemoembolization.
Topics: Acrylates; Animals; Doxorubicin; Embolization, Therapeutic; Microspheres; Particle Size; Rabbits
PubMed: 30562784
DOI: No ID Found -
AJNR. American Journal of Neuroradiology Apr 2019The safety and efficacy of flow diversion among distal anterior circulation aneurysms must be proved. (Meta-Analysis)
Meta-Analysis
BACKGROUND
The safety and efficacy of flow diversion among distal anterior circulation aneurysms must be proved.
PURPOSE
Our aim was to analyze the outcomes after flow diversion among MCA, anterior communicating artery, and distal anterior cerebral artery aneurysms.
DATA SOURCES
A systematic search of 3 databases was performed for studies published from 2005 to 2018.
STUDY SELECTION
According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we included studies reporting flow diversion of distal anterior circulation aneurysms.
DATA ANALYSIS
Random-effects meta-analysis was used to pool aneurysm occlusion and complication rates. From the individual patient data, univariate and multivariate analyses were used to test predictors of occlusion and complications.
DATA SYNTHESIS
We included 27 studies (484 aneurysms). The long-term adequate occlusion rate (O'Kelly-Marotta scale, C-D) was 82.7% (295/364; 95% CI, 77.4%-87.9%; I = 52%). Treatment-related complications were 12.5% (63/410; 95% CI, 9%-16%%; I = 18.8%), with 5.4% (29/418; 95% CI, 3.2%-7.5%; I = 0%) morbidity. MCA location was an independent factor associated with lower occlusion (OR = 0.5, = .03) and higher complication rates (OR = 1.8, = .02), compared with anterior communicating artery and distal anterior cerebral artery aneurysms. The Pipeline Embolization Device (versus other stents) gave better occlusion rates (OR = 2.6, = .002), whereas large/giant aneurysms were associated with higher odds of complications (OR = 2.2, = .03). The rates of occlusion and narrowing of arteries covered by flow-diverter stents were 6.3% (29/283; 95% CI, 3.5%-9.1%; I = 4.2%) and 23.8% (69/283; 95% CI, 15.7%-32%; I = 80%), respectively. Symptoms related to occlusion and narrowing of the jailed arteries were 3.5% (6/269; 95% CI, 1.1%-5%; I = 0%) and 3% (6/245; 95% CI, 1%-4%; I = 0%), respectively.
LIMITATIONS
We reviewed small and retrospective series.
CONCLUSIONS
Flow diversion among distal anterior circulation aneurysms is effective, leading to adequate aneurysm occlusion in 83% of cases. However, this strategy has some limitations among MCA and larger lesions, especially related to the higher rate of complications. Compared with the other devices, the Pipeline Embolization Device seems to be associated with a higher occlusion rate.
Topics: Adult; Aged; Blood Vessel Prosthesis; Embolization, Therapeutic; Endovascular Procedures; Female; Humans; Intracranial Aneurysm; Male; Middle Aged; Retrospective Studies; Stents; Treatment Outcome
PubMed: 30872418
DOI: 10.3174/ajnr.A6002 -
Interventional Neuroradiology : Journal... Feb 2022We report a case of a 64-year-old man with a fusiform right extracranial vertebral artery aneurysm, spanning over half the extra-cranial V2 (foraminal) segment,... (Review)
Review
We report a case of a 64-year-old man with a fusiform right extracranial vertebral artery aneurysm, spanning over half the extra-cranial V2 (foraminal) segment, presenting with recurrent multi-focal posterior circulation embolic ischaemic stroke. The patient was treated with endovascular embolisation of the right vertebral artery to prevent further thrombo-embolic events. Distal and proximal occlusion of the aneurysmal vertebral artery was performed with a micro-vascular plug with partial aneurysm sack embolisation to aid thrombosis and reduce the risk of recanalisation. Two months post procedure MR angiography confirmed successful aneurysm occlusion with no post-procedural complication. The patient returned to his normal independent life. Endovascular treatment with vessel sacrifice is an effective treatment with low morbidity and we believe the MVP device to be a efficacious option in the vertebral artery.
Topics: Aneurysm; Brain Ischemia; Embolization, Therapeutic; Humans; Intracranial Aneurysm; Male; Middle Aged; Stroke; Vertebral Artery
PubMed: 34000865
DOI: 10.1177/15910199211018581 -
Journal of the American College of... Oct 2005The discrepancy between angiographic success and microvascular perfusion has been recognized for some time. In the face of an open artery, the degree of microvascular... (Review)
Review
The discrepancy between angiographic success and microvascular perfusion has been recognized for some time. In the face of an open artery, the degree of microvascular perfusion determines post-infarct prognosis. Despite successful epicardial recanalization, tissue perfusion may be absent in up to 25% patients with acute myocardial infarction. Historically associated with saphenous vein graft intervention, embolization is increasingly recognized in native coronary arteries, particularly in patients undergoing primary percutaneous coronary intervention (PCI). With more than two million PCI procedures performed worldwide each year, there is enormous interest in protecting the left ventricular myocardium from embolization during PCI. This article reviews the evidence for distal myocardial protection and discusses the relative merits of the different available techniques.
Topics: Angioplasty, Balloon, Coronary; Balloon Occlusion; Embolism; Equipment Design; Humans
PubMed: 16226166
DOI: 10.1016/j.jacc.2005.04.061 -
AJNR. American Journal of Neuroradiology Apr 2014Low-porosity endoluminal devices for the treatment of intracranial aneurysms, also known as flow diverters, have been in experimental and clinical use for close to 10...
BACKGROUND AND PURPOSE
Low-porosity endoluminal devices for the treatment of intracranial aneurysms, also known as flow diverters, have been in experimental and clinical use for close to 10 years. Despite rigorous evidence of their safety and efficacy in well-controlled trials, a number of key factors concerning their use remain poorly defined. Among these, none has received more attention to date than the debate on how many devices are optimally required to achieve a safe, effective, and economical outcome. Additional, related questions concern device sizing relative to the parent artery and optimal method of deployment of the devices. While some or all of these issues may be ultimately answered on an empiric basis via subgroup analysis of growing treatment cohorts, we believe that careful in vitro examination of relevant device properties can also help guide its in vivo use.
MATERIALS AND METHODS
We conducted a number of benchtop experiments to investigate the varied porosity of Pipeline Embolization Devices deployed in a simulated range of parent vessel diameters and applied these results toward conceptualizing optimal treatment strategies of fusiform and wide-neck aneurysms.
RESULTS
The results of our studies confirm a predictable parabolic variability in device porosity based on the respective comparative sizes of the device and recipient artery, as well as device curvature. Even modest oversizing leads to a significant increase in porosity.
CONCLUSIONS
The experiments demonstrate various deleterious effects of device oversizing relative to the parent artery and provide strategies for addressing size mismatches when they are unavoidable.
Topics: Blood Vessel Prosthesis; Cerebral Arteries; Embolization, Therapeutic; Equipment Design; Humans; Intracranial Aneurysm; Metals; Organ Size; Porosity; Stents
PubMed: 24072622
DOI: 10.3174/ajnr.A3742 -
AJNR. American Journal of Neuroradiology Apr 2020Flow-diverter treatment for previously stented aneurysms has been reported to be less effective and prone to complications. In this study, we evaluated the effectiveness...
BACKGROUND AND PURPOSE
Flow-diverter treatment for previously stented aneurysms has been reported to be less effective and prone to complications. In this study, we evaluated the effectiveness and safety of flow diverters for recurrent aneurysms after stent-assisted coiling.
MATERIALS AND METHODS
Patients who underwent flow-diverter placement for recurrent aneurysms after stent-assisted coiling between March 2015 and March 2019 were recruited. Clinical and radiographic characteristics and clinical and angiographic outcomes were retrospectively evaluated.
RESULTS
Among 133 patients who underwent flow-diverter insertion, 17 (male/female ratio = 5:12; mean age, 53.8 years) were treated for recurrent aneurysms after stent placement with ( = 16) or without ( = 1) coiling. Eight patients initially presented with subarachnoid hemorrhage; 7, with headache; and 2, with visual field defects. Angiographic morphology included large/giant saccular in 12 patients, dissecting in 2, fusiform in 1, traumatic pseudoaneurysm in 1, and ruptured blood blister-like aneurysm in 1. The duration between the first treatment and flow-diverter placement ranged from 2 weeks to 15 months (median, 6 months). Flow-diverter placement was successful in all cases without any complications. All patients had favorable outcomes (mRS, 0-2), without any newly appearing symptoms. Aneurysms were followed up with conventional angiography at least once in 6-18 months. Sixteen aneurysms showed complete occlusion, and 1 aneurysm was enlarged.
CONCLUSIONS
Results from this case series investigating flow-diverter placement for recurrent aneurysms after stent-assisted coiling suggested that the procedure is safe and effective. Further study in a larger population may be warranted.
Topics: Adult; Aged; Blood Vessel Prosthesis; Embolization, Therapeutic; Endovascular Procedures; Female; Humans; Intracranial Aneurysm; Male; Middle Aged; Recurrence; Reoperation; Retrospective Studies; Stents; Treatment Outcome
PubMed: 32165365
DOI: 10.3174/ajnr.A6476 -
The Neuroradiology Journal Oct 2019Aneurysms arising from the communicating segment (C7) of the internal carotid artery (ICA) are one of the most frequent locations of intracranial aneurysms.... (Comparative Study)
Comparative Study
No differences in effectiveness and safety between pipeline embolization device and stent-assisted coiling for the treatment of communicating segment internal carotid artery aneurysms.
BACKGROUND
Aneurysms arising from the communicating segment (C7) of the internal carotid artery (ICA) are one of the most frequent locations of intracranial aneurysms. Stent-assisted coiling (SAC) and flow diversion therapies are both endovascular strategies used for the treatment of ICA aneurysms occurring at the C7 segment.
OBJECTIVE
The aim of this study is to compare both methods' angiographic and functional outcomes, and procedural complications. To our knowledge, this is the first study to compare both modalities for aneurysms at this location.
METHODS
A retrospective review was performed of our prospectively collected database from 2008 until 2017 for patients treated with SAC and from 2013 until 2017 for patients treated with pipeline embolization devices (PEDs).
RESULTS
We identified 35 patients for this cohort with 38 aneurysms; 17 treated with SAC and 21 with PED. Mean age was 59 years, and 30 patients were female (86%). Complete occlusion at last follow-up occurred in 70.6% of patients in the SAC group and in 81% in the PED group ( = 0.45). Posterior communicating artery patency at last follow-up did not differ significantly between the two groups (94.1% vs 85.7%; = 0.40). Good functional outcome at last follow-up (mRS 0-2) was achieved in 100% and 88.2% of patients, respectively. Additionally, there was no significant difference between the two groups for retreatment rates, procedural hemorrhagic, or thromboembolic complications.
CONCLUSION
SAC and PED are two equally efficacious modalities for endovascular treatment of ICA aneurysms arising at the communicating segment of the ICA.
Topics: Angiography, Digital Subtraction; Carotid Artery Diseases; Carotid Artery, Internal; Embolization, Therapeutic; Female; Humans; Intracranial Aneurysm; Magnetic Resonance Angiography; Male; Middle Aged; Multimodal Imaging; Patient Safety; Prospective Studies; Retrospective Studies; Stents; Treatment Outcome
PubMed: 30998116
DOI: 10.1177/1971400919845368 -
Cardiovascular and Interventional... Jul 2009Intra-arterial radiotherapy with yttrium-90 microspheres (radioembolization) is a therapeutic procedure exclusively applied to the liver that allows the direct delivery...
Intra-arterial radiotherapy with yttrium-90 microspheres (radioembolization) is a therapeutic procedure exclusively applied to the liver that allows the direct delivery of high-dose radiation to liver tumors, by means of endovascular catheters, selectively placed within the tumor vasculature. The aim of the study was to describe the distribution of spheres within the precapillaries, inflammatory response, and recannalization characteristics after embolization with nonradioactive resin microspheres in the kidney and liver. We performed a partial embolization of the liver and kidney vessels in nine white pigs. The left renal and left hepatic arteries were catheterized and filled with nonradioactive resin microspheres. Embolization was defined as the initiation of near-stasis of blood flow, rather than total occlusion of the vessels. The hepatic circulation was not isolated so that the effects of reflux of microspheres into stomach could be observed. Animals were sacrificed at 48 h, 4 weeks, and 8 weeks, and tissue samples from the kidney, liver, lung, and stomach evaluated. Microscopic evaluation revealed clusters of 10-30 microspheres (15-30 microm in diameter) in the small vessels of the kidney (the arciform arteries, vasa recti, and glomerular afferent vessels) and liver. Aggregates were associated with focal ischemia and mild vascular wall damage. Occlusion of the small vessels was associated with a mild perivascular inflammatory reaction. After filling of the left hepatic artery with microspheres, there was some evidence of arteriovenous shunting into the lungs, and one case of cholecystitis and one case of marked gastritis and ulceration at the site of arterial occlusion due to the presence of clusters of microspheres. Beyond 48 h, microspheres were progressively integrated into the vascular wall by phagocytosis and the lumen recannalized. Eight-week evaluation found that the perivascular inflammatory reaction was mild. Liver cell damage, bile duct injury, and portal space fibrosis were not observed. In conclusion, resin microspheres (15-30 microm diameter) trigger virtually no inflammatory response in target tissues (liver and kidney). Clusters rather than individual microspheres were associated with a mild to moderate perivascular inflammatory reaction. There was no evidence of either a prolonged inflammatory reaction or fibrosis in the liver parenchyma following recannalization.
Topics: Acrylic Resins; Animals; Biocompatible Materials; Embolization, Therapeutic; Inflammation; Kidney; Liver; Microspheres; Models, Animal; Particle Size; Swine
PubMed: 19449060
DOI: 10.1007/s00270-009-9592-9 -
Journal of Neurointerventional Surgery Jan 2017Coil embolization of ruptured aneurysms has become the standard treatment in many situations. However, certain aneurysm morphologies pose technical difficulties and may...
INTRODUCTION
Coil embolization of ruptured aneurysms has become the standard treatment in many situations. However, certain aneurysm morphologies pose technical difficulties and may require the use of adjunctive devices.
OBJECTIVE
To present our experience with the pCONus, a new neck bridging device, as an adjunct to coil embolization for acutely ruptured aneurysms and discuss the technical success, angiographic and clinical outcomes.
METHODS
We conducted a retrospective review of our database of prospectively collected data to identify all patients who presented with acute subarachnoid hemorrhage that required adjunctive treatment with the pCONus in the acute stage. We searched the database between April 2011 and April 2016.
RESULTS
21 patients were identified (13 male, 8 female) with an average age of 54.6 years (range 31-73). 8 aneurysms were located at the basilar artery tip, 7 at the anterior communicating artery, 4 at the middle cerebral artery bifurcation, 1 pericallosal, and 1 basilar fenestration. 61.8% patients achieved modified Raymond-Roy classification I or II at immediate angiography, with 75% of patients having completely occluded aneurysms or stable appearance at initial follow-up. There were no repeat aneurysmal ruptures and two device-related complications (no permanent morbidity). Four patients in our cohort died.
CONCLUSIONS
Use of the pCONus is safe and effective in patients with acutely ruptured aneurysms and carries a high rate of technical success.
Topics: Acute Disease; Adult; Aged; Aneurysm, Ruptured; Anterior Cerebral Artery; Basilar Artery; Blood Vessel Prosthesis; Cerebral Angiography; Embolization, Therapeutic; Female; Humans; Intracranial Aneurysm; Male; Middle Aged; Prospective Studies; Retrospective Studies; Stents; Subarachnoid Hemorrhage; Treatment Outcome
PubMed: 27411859
DOI: 10.1136/neurintsurg-2016-012508 -
BMJ Case Reports Sep 2019Embolisation of neonatal arteriovenous shunts poses several challenges: tortuous and fragile vessels, limited contrast volume and few specialised paediatric endovascular...
Embolisation of neonatal arteriovenous shunts poses several challenges: tortuous and fragile vessels, limited contrast volume and few specialised paediatric endovascular devices. In a 9-day-old patient with a choroidal type vein of Galen malformation we encountered an extremely tortuous posterior choroidal artery pedicle during endovascular treatment. After attempted selection using a traditional over-the-wire technique, we advanced a platinum coil through the micro-catheter. High flow within the feeder directed the soft and malleable coil anterograde. We then advanced the catheter over the coil's pusher wire in a facile manner to an ideal position for embolisation. This approach may be especially useful in cases requiring coil/vinyl-based liquid embolics, given that the only flow-directed micro-catheter available to most operators is compatible with n-Butyl cyanoacrylate alone. Moreover, the soft distal portion of coil may impart a safety benefit over traditional guidewires in easily perforated neonatal vasculature.
Topics: Angiography, Digital Subtraction; Catheterization; Cerebral Veins; Embolization, Therapeutic; Female; Humans; Infant, Newborn; Intracranial Arteriovenous Malformations
PubMed: 31488452
DOI: 10.1136/bcr-2019-231549