No inferiority of Tonbridge thrombectomy device for acute thrombus retrial compared with Solitaire device: an experimental evaluation with a canine distal external carotid-maxillary artery occlusion model

2018 ◽  
Vol 10 (11) ◽  
pp. 1085-1091 ◽  
Author(s):  
Geng Zhou ◽  
Ming-Hua Li ◽  
Hai-Tao Lu ◽  
Jiang-Shan Deng ◽  
Yu-Wu Zhao ◽  
...  
Keyword(s):  
Mechanical Performance ◽  
External Carotid ◽  
Maxillary Artery ◽  
In Vitro Test ◽  
New Device ◽  
Occlusion Model ◽  
Flow Restoration ◽  
Thrombectomy Device ◽  
The Right

IntroductionMechanical thrombectomy (MT) has been widely accepted as a safe and effective treatment for acute ischemic stroke (AIS). Development of stent retriever devices has been intensively developed over the past two decades. In this study, we compared the effectiveness and safety of a new thrombectomy device with Solitaire FR for the treatment of AIS models.MethodsMechanical performance of stent retrievers was tested in vitro. Thrombin-induced thrombus was pre-injected into the right distal external carotid-maxillary artery in 18 dogs to create an acute thrombus occlusion model, and these animals were divided into a Tonbridge group (n=9, with Tonbridge stent Tonbridge Medical Technology) and a Solitaire group as control (n=9, with Solitaire stent, ev3 Neurovascular). Final flow restoration, side branches, recanalization time, distal vessel embolism, and device-related complications were recorded and compared. A post-procedure angiogram was obtained at 30 and 90 days after thrombectomy. Device manipulation-related damage to the arterial walls was evaluated histologically.ResultsIn vitro test showed that the maximum friction within the microcatheter was 0.763 for the Tonbridge device and 0.784 n for the Solitaire (P>0.05). Slight increase in radial force was noticed for the Tonbridge (0.035 N/mm vs 0.031 N/mm of Solitaire, P>0.05). Eighteen and 16 retriever attempts were done in the Tonbridge (mean 2.0 attempts) and the Solitaire (mean 1.8 attempts) groups (P=0.74). The Tonbridge device led to good flow restoration in all nine (100%) models compared with eight (88.9%) in the Solitaire group (P=0.30). Side branches' influence (P=0.39), distal thromboembolism (P=0.60), and device-related complications (P=1.00) found no difference between the two groups. The rates of disruption of the internal elastic lamina (IEL) were 8.3% (2/24) and 4.2% (1/24) of the specimens, respectively (P=0.683). TICI 2b/3 flow of the right CCA were similar between the two groups at 1 (6/6 vs 6/6) and 3 months (6/6 vs 6/6) follow-up (P>0.05).ConclusionOur preliminary study indicated this new device was technically feasible and effective to be used in thrombectomy for the treatment of acute thrombus occlusion in canine models.

scholarly journals Combined surgical treatment of arteriovenous malformation of the lower jaw

2020 ◽  
Vol 34 (4) ◽  
pp. 95-104
Author(s):  
D.V. Shchehlov ◽  
V.M. Zahorodnii ◽  
I.V. Altman ◽  
N.V. Kiselyova ◽  
I.I. Kashkish
Keyword(s):  
Arteriovenous Malformation ◽  
Cerebral Angiography ◽  
Combined Treatment ◽  
The Body ◽  
Facial Artery ◽  
External Carotid ◽  
Maxillary Artery ◽  
Terminal Branch ◽  
Lower Jaw ◽  
The Right

The objective – to presents the observation of combined treatment of a patient with arteriovenous malformation of the lower jaw.A man, 21 years old, was hospitalized in the Scientific-Practical Center of Endovascular Neuroradiology NAMS of Ukraine with complaints of bleeding from a tooth socket after an attempt to remove the 6th tooth (first painter) of the lower jaw on the left. According to the performed survey radiography of the lower jaw, an aneurysmal bone cyst was revealed in the body of the lower jaw on the left, corresponding to the localization of bleeding. According to cerebral angiography, an arteriovenous malformation of the lower jaw was revealed on the left, the afferent arteries of which were: the right facial artery (a branch of the right external carotid artery (ECA)), the left facial artery (a branch of the left ECA), the lower alveolar artery, the superior-posterior alveolar artery (branches of the maxillary artery ‒ the terminal branch of the left ECA) with drainage into a vein, which was located in the body of the lower jaw. In order to exclude the malformation from the bloodstream and prevent bleeding, a controlled embolization of the malformation was performed using non-spherical emboli – polyvinyl alcohol (PVA) particles from Cook, USA. Using a transfemoral approach, a guide catheter was inserted into the orifice of the ECA, then a Headway 27 microcatheter (Microvention, USA) was passed through it along a Traxes 14 guide wire (Microvention, USA), the afferent arteries of the malformation were selectively cathete-rized in turn, and embolization was performed after superselective angiography. The patient was discharged in a satisfactory condition. Two weeks after the operation, the bleeding resumed. The performed control cerebral angiography revealed a relapse of the malformation with a change in its angioarchitectonics ‒ the filling of the malformation in the late arterial and venous phases of cerebral blood flow was noted. Re-embolization was performed using PVA emboli (Cook), which was supplemented by transcutaneous puncture of the drainage vein in the mandible and its embolization with histoacryl (B. Braun, Germany) and lipiodol (Guerbet, France) in a 1 : 1 ratio. Results. As a result of using this technique, it was possible to turn off the malformation completely. For 6 months from the moment of surgery, no bleeding was noted, and subsequently the patient had a tooth removed without complications.Conclusions. The proposed method for treating arteriovenous malformation of the lower jaw, proposed in this case, showed the effectiveness of a combination of endovascular embolization in combination with transcutaneous embolization of the draining vein and can be successfully used to treat this pathology.

scholarly journals Elastomeric Electrospun Scaffolds of a Biodegradable Aliphatic Copolyester Containing PEG-Like Sequences for Dynamic Culture of Human Endothelial Cells

Biomolecules ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1620
Author(s):  
Luca Fusaro ◽  
Chiara Gualandi ◽  
Diego Antonioli ◽  
Michelina Soccio ◽  
Anna Liguori ◽  
...  
Keyword(s):  
Blood Vessels ◽  
Vascular Tissue ◽  
Mechanical Performance ◽  
Thrombus Formation ◽  
Cell Activity ◽  
Mechanical Tests ◽  
Cyclic Stretch ◽  
Biological Characterization ◽  
The Right

In the field of artificial prostheses for damaged vessel replacement, polymeric scaffolds showing the right combination of mechanical performance, biocompatibility, and biodegradability are still demanded. In the present work, poly(butylene-co-triethylene trans-1,4-cyclohexanedicarboxylate), a biodegradable random aliphatic copolyester, has been synthesized and electrospun in form of aligned and random fibers properly designed for vascular applications. The obtained materials were analyzed through tensile and dynamic-mechanical tests, the latter performed under conditions simulating the mechanical contraction of vascular tissue. Furthermore, the in vitro biological characterization, in terms of hemocompatibility and cytocompatibility in static and dynamic conditions, was also carried out. The mechanical properties of the investigated scaffolds fit within the range of physiological properties for medium- and small-caliber blood vessels, and the aligned scaffolds displayed a strain-stiffening behavior typical of the blood vessels. Furthermore, all the produced scaffolds showed constant storage and loss moduli in the investigated timeframe (24 h), demonstrating the stability of the scaffolds under the applied conditions of mechanical deformation. The biological characterization highlighted that the mats showed high hemocompatibility and low probability of thrombus formation; finally, the cytocompatibility tests demonstrated that cyclic stretch of electrospun fibers increased endothelial cell activity and proliferation, in particular on aligned scaffolds.

scholarly journals Enhancement the Osseo Integration Properties of Polymer for Human Body Implants

2020 ◽  
Vol 23 (4) ◽  
pp. 331-337
Author(s):  
Dhurgham Majid Rasheed ◽  
Dunya Abdulsahib Hamdi
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Grain Boundaries ◽  
Mechanical Performance ◽  
Wear Test ◽  
High Energy ◽  
In Vitro Test ◽  
Scanning Electron

In this research, polymer polymethyl methacrylate PMMA composite with nano ceramic Zr and HAp material were used to manufacture one part of the implant system (femoral ball head of hip implant). Three set of hybrid materials were fabricated and tested for this study; the first mixtures which contains 100% (PMMA), the second mixtures which contains (90% (PMMA) + 8% (Zr) + 2% (HAp)), and the third mixtures which contains (80% (PMMA) + 18% (Zr) + 2% (HAp)) were investigated. The mechanical properties for these mixtures increased with the increasing of nano ceramic concentration (Zr and HAp) composite material in the polymer compared to pure polymer PMMA sample. However, an increase in the concentration of Zr from 8% to 18% content cause a considerable decrease of the hardness where a drop of homogeneity in Zr- matrix PMMA contact occurred, V Hardness value are (68 ,80 and 70) Kg.mm for three mixture respectively. The wear test was in agreement with results of the hardness test. The weight loss of the above samples of the wear test were (0.041, 0.035 and 0.037) respectively. According to mechanical properties, the best sample contains (90% (PMMA) + 8% (Zr) + 2% (HAp)). The Scanning electron microscopy resolute showed the particles forming semi-continuous network along grain boundaries polymer for second sample mixtures containing (90% (PMMA) + 8% (Zr) + 2% (HAp)), provides a low atomic packing and high energy. This will make the grain boundaries more reactive and strengthen mechanical performance. The Optical microscopy, Scanning electron microscopy and Xray spectroscopy analysis for In vitro test using SBF shows the growth of HAp layer with an increase in concentration of Ca and P elements formed on the surface of the second sample. This display of good results is a proof of the biocompatibility of the polymer sample.

Transarterial N-Butyl-2-cyanoacrylate Embolization of an Intraosseous Dural Arteriovenous Fistula Associated With Acute Epidural Hematoma: Technical Case Report

2015 ◽  
Vol 11 (3) ◽  
pp. E468-E471 ◽  
Author(s):  
Shotaro Yoshioka ◽  
Kazuyuki Kuwayama ◽  
Junichiro Satomi ◽  
Shinji Nagahiro
Keyword(s):  
Epidural Hematoma ◽  
Clinical Presentation ◽  
Middle Meningeal Artery ◽  
Endovascular Embolization ◽  
External Carotid Artery ◽  
External Carotid ◽  
Maxillary Artery ◽  
Microsurgical Anatomy ◽  
The Right ◽  
Acute Epidural Hematoma

Abstract BACKGROUND AND IMPORTANCE Intraosseous dural arteriovenous fistulae (DAVF) are rare, especially those with drainage into the diploic venous system. The clinical presentation depends on the location of the lesion. This is the first report of an intraosseous DAVF associated with acute epidural hematoma. CLINICAL PRESENTATION A 25-year-old man presented with headache and nausea. Imaging of the brain revealed abnormal signals indicative of acute epidural hematoma in the right frontal convexity. Angiography demonstrated a DAVF in the region of the frontal bone. Right external carotid artery angiography showed that the DAVF was fed mainly by the right middle meningeal artery with drainage into diploic veins. Immediately after embolization of the middle meningeal and the distal internal maxillary artery with 17% N-butyl-2-cyanoacrylate, the shunt was completely occluded. The patient was discharged 4 days later without clinical complications. CONCLUSION Intraosseous DAVF can be treated by surgical resection or endovascular embolization. Curative treatment requires careful inspection of the angiographic architecture and microsurgical anatomy.

Intraluminal Doppler-Sonography: Analysis and “in Vitro Test” of a New Device

1992 ◽  
pp. 341-346
Author(s):  
Th. Roth ◽  
R. Brennecke ◽  
H. Conradi ◽  
R. Erbel ◽  
J. Meyer ◽  
...  
Keyword(s):  
Doppler Sonography ◽  
In Vitro Test ◽  
New Device ◽  
Vitro Test

What to do about fibrin rich ‘tough clots’? Comparing the Solitaire stent retriever with a novel geometric clot extractor in an in vitro stroke model

2018 ◽  
Vol 10 (9) ◽  
pp. 907-910 ◽  
Author(s):  
Vernard S Fennell ◽  
Swetadri Vasan Setlur Nagesh ◽  
Karen M Meess ◽  
Liza Gutierrez ◽  
Rhys H James ◽  
...  
Keyword(s):  
Stent Retriever ◽  
Experimental Stroke ◽  
Control Group ◽  
Large Vessel Occlusion ◽  
Stroke Model ◽  
Vessel Occlusion ◽  
Flow Restoration ◽  
Thrombectomy Device ◽  
Cerebrovascular Occlusion

BackgroundDespite advances in revascularization tools for large vessel occlusion presenting as acute ischemic stroke, a significant subset of clots remain recalcitrant to current strategies. We assessed the effectiveness of a novel thrombectomy device that was specifically designed to retrieve resistant fibrin rich clots, the geometric clot extractor (GCE; Neuravi, Galway, Ireland), in an in vitro cerebrovascular occlusion stroke model.MethodsAfter introducing fibrin rich clot analogues into the middle cerebral artery of the model, we compared the rates of recanalization between GCE and Solitaire flow restoration stent retriever (SR; Medtronic, Minneapolis, Minnesota, USA; control group) cases. A maximum of three passes of each device was allowed. If the SR failed to recanalize the vessel after three passes, one pass of the GCE was allowed (rescue cases).ResultsIn a total of 26 thrombectomy cases (13 GCE, 13 SR), successful recanalization (Thrombolysis in Cerebral Infarction score of 2b or 3) was achieved 100% of the time in the GCE cases with an average of 2.13 passes per case. This rate was significantly higher compared with the Solitaire recanalization rate (7.7%, P<0.0001) with an average of three passes per case. After SR failure (in 92% of cases), successful one pass GCE rescue recanalization was achieved 66% of the time (P<0.005).ConclusionApplication of the GCE in this experimental stroke model to retrieve typically recalcitrant fibrin rich clots resulted in higher successful recanalization rates than the SR.

Evaluation of 99mTc-Label led Vitamin K4 as an Agent for Testicular Imaging

1991 ◽  
Vol 30 (01) ◽  
pp. 35-39 ◽  
Author(s):  
H. S. Durak ◽  
M. Kitapgi ◽  
B. E. Caner ◽  
R. Senekowitsch ◽  
M. T. Ercan
Keyword(s):  
Soft Tissue ◽  
Room Temperature ◽  
Normal Subjects ◽  
Left Testis ◽  
Wide Range ◽  
Activity Ratios ◽  
The Right ◽  
Radioactivity Levels

Vitamin K4 was labelled with 99mTc with an efficiency higher than 97%. The compound was stable up to 24 h at room temperature, and its biodistribution in NMRI mice indicated its in vivo stability. Blood radioactivity levels were high over a wide range. 10% of the injected activity remained in blood after 24 h. Excretion was mostly via kidneys. Only the liver and kidneys concentrated appreciable amounts of radioactivity. Testis/soft tissue ratios were 1.4 and 1.57 at 6 and 24 h, respectively. Testis/blood ratios were lower than 1. In vitro studies with mouse blood indicated that 33.9 ±9.6% of the radioactivity was associated with RBCs; it was washed out almost completely with saline. Protein binding was 28.7 ±6.3% as determined by TCA precipitation. Blood clearance of 99mTc-l<4 in normal subjects showed a slow decrease of radioactivity, reaching a plateau after 16 h at 20% of the injected activity. In scintigraphic images in men the testes could be well visualized. The right/left testis ratio was 1.08 ±0.13. Testis/soft tissue and testis/blood activity ratios were highest at 3 h. These ratios were higher than those obtained with pertechnetate at 20 min post injection.99mTc-l<4 appears to be a promising radiopharmaceutical for the scintigraphic visualization of testes.

Haemostatic Platelet Plug Formation in the Isolated Rabbit Mesenteric Preparation - An Analysis of Red Blood Cell Participation

1980 ◽  
Vol 44 (01) ◽  
pp. 006-008 ◽  
Author(s):  
D Bergqvist ◽  
K-E Arfors
Keyword(s):  
Whole Blood ◽  
Platelet Rich Plasma ◽  
Adenosine Diphosphate ◽  
In Vitro Test ◽  
Pharmacological Agents ◽  
Vitro Test ◽  
Releasing Effect ◽  
Plug Formation

SummaryIn a model using an isolated rabbit mesenteric preparation microvessels were transected and the time until haemostatic plugs formed was registered. Perfusion of platelet rich plasma gave no haemostasis whereas whole blood did. Addition of chlorpromazine or adenosine to the whole blood significantly prolonged the time for haemostasis, and addition of ADP to the platelet rich plasma significantly shortened it. It is concluded that red cells are necessary for a normal haemostasis in this model, probably by a combination of a haemodynamic and ADP releasing effect.The fundamental role of platelets in haemostatic plug formation is unquestionable but there are still problems concerning the stimulus for this process to start. Three platelet aggregating substances have been discussed – thrombin, adenosine diphosphate (ADP) and collagen. Evidence speaking in favour of thrombin is, however, very minimal, and the discussion has to be focused on collagen and ADP. In an in vitro system using polyethylene tubings we have shown that "haemostasis" can be obtained without the presence of collagen but against these results can be argued that it is only another in vitro test for platelet aggregation (1).To be able to induce haemostasis in this model, however, the presence of red blood cells is necessary. To further study this problem we have developed a model where haemostatic plug formation can be studied in the isolated rabbit mesentery and we have briefly reported on this (2).Thus, it is possible to perfuse the vessels with whole blood as well as with platelet rich plasma (PRP) and different pharmacological agents of importance.

Enhanced Increases in Cytosolic Ca2+ in ADP-Stimulated Platelets from Patients with Delta-Storage Pool Deficiency – A Possible Indicator of Interactions between Granule-Bound ADP and the Membrane ADP Receptor

1997 ◽  
Vol 77 (02) ◽  
pp. 376-382 ◽  
Author(s):  
Bruce Lages ◽  
Harvey J Weiss
Keyword(s):  
Platelet Rich Plasma ◽  
Limited Range ◽  
Dense Granule ◽  
Receptor Desensitization ◽  
Fura 2 ◽  
Storage Pool ◽  
Low Levels ◽  
The Right

SummaryThe possible involvement of secreted platelet substances in agonist- induced [Ca2+]i increases was investigated by comparing these increases in aspirin-treated, fura-2-loaded normal platelets and platelets from patients with storage pool deficiencies (SPD). In the presence and absence of extracellular calcium, the [Ca2+]i response induced by 10 µM ADP, but not those induced by 0.1 unit/ml thrombin, 3.3 µM U46619, or 20 µM serotonin, was significantly greater in SPD platelets than in normal platelets, and was increased to the greatest extent in SPD patients with Hermansky-Pudlak syndrome (HPS), in whom the dense granule deficiencies are the most severe. Pre-incubation of SPD-HPS and normal platelets with 0.005-5 µM ADP produced a dose-dependent inhibition of the [Ca2+]i response induced by 10 µ M ADP, but did not alter the [Ca2+]i increases induced by thrombin or U46619. Within a limited range of ADP concentrations, the dose-inhibition curve of the [Ca2+]i response to 10 µM ADP was significantly shifted to the right in SPD-HPS platelets, indicating that pre-incubation with greater amounts of ADP were required to achieve the same extent of inhibition as in normal platelets. These results are consistent with a hypothesis that the smaller ADP-induced [Ca2+]i increases seen in normal platelets may result from prior interactions of dense granule ADP, released via leakage or low levels of activation, with membrane ADP receptors, causing receptor desensitization. Addition of apyrase to platelet-rich plasma prior to fura-2 loading increased the ADP-induced [Ca2+]i response in both normal and SPD-HPS platelets, suggesting that some release of ADP derived from both dense granule and non-granular sources occurs during in vitro fura-2 loading and platelet washing procedures. However, this [Ca2+]i response was also greater in SPD-HPS platelets when blood was collected with minimal manipulation directly into anticoagulant containing apyrase, raising the possibility that release of dense granule ADP resulting in receptor desensitization may also occur in vivo. Thus, in addition to enhancing platelet activation, dense granule ADP could also act to limit the ADP-mediated reactivity of platelets exposed in vivo to low levels of stimulation.

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