nitinol and Aneurysm

Topics: Aged; Alloys; Aneurysm; Angiography, Digital Subtraction; Catheterization; Humans; Iliac Artery; Male; Polyethylene Terephthalates; Stents

The objective is to report the feasibility and technique of treating popliteal artery aneurysms (PAA) with a stent made of nitinol rings externally supported by thin polyester (Anaconda limbs).. PAA are the most common peripheral aneurysms. The main limitations of stents used in these settings are: short lengths, longitudinal and horizontal compliance mismatch; graft failure from angulation and movement at the joint level; and dislodgment.. This is a prospective multicenter cohort study of consecutive symptomatic and asymptomatic PAA treated in tertiary vascular centers. Outcomes included patency of the stent and postoperative time-to-independent-ambulation and to-climb-a-flight-of-stairs.. Fourteen PAA were treated in 12 men, age 72 +/- 3 years. The median ASA classification was 2.5. The length of artery covered was 147 +/- 41 mm. The PAA diameter was 31 +/- 5 mm, 6 were symptomatic. One stent was used in 6 aneurysms, two in 7, and three in 1. The average stent diameter was 10 +/- 1 mm. The length of the proximal neck was 24 +/- 6 mm with a diameter of 9.8 +/- 1.9, and length of the distal neck 23 +/- 3 mm with a diameter of 8.7 +/- 1.2 mm. In 6 aneurysms, the stent crossed the knee joint. There was no mortality, and one stent occluded (primary patency 93% at 6 +/- 3 months). The median hospital stay was 1.7 days, time to independent ambulation was 3 hr and the time to climbing a flight of stairs was 1 day.. The use of Anaconda limbs for endovascular repair of PAA is feasible and safe.

Topics: Activities of Daily Living; Aged; Alloys; Aneurysm; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Feasibility Studies; Humans; Length of Stay; Male; Ontario; Pilot Projects; Polyesters; Popliteal Artery; Prospective Studies; Prosthesis Design; Recovery of Function; Stents; Time Factors; Tomography, X-Ray Computed; Treatment Outcome; Vascular Patency; Walking

Saccular aneurysm of the extracranial internal carotid artery is rare. We present a 56-year-old lady presented with a progressively enlarging pulsatile swelling over the right neck, and the right internal carotid artery aneurysm was successfully treated with trans-carotid endovascular stenting of right common to right carotid artery using a self-expanding nitinol base ePTFE covered stent (COVERA Plus™ stent, Bard, Tempe, USA). The external carotid artery was prophylactically embolised to prevent back bleeding. New generation covered stents have consistently improved flexibility and conformability, and this is to our knowledge the first reported case in the world's literature of using this type of self-expanding nitinol base ePTFE covered stent in endovascular stenting of carotid artery aneurysms, with excellent short-term results.

Topics: Aneurysm; Carotid Artery Diseases; Carotid Artery, Internal; Endovascular Procedures; Female; Humans; Middle Aged; Stents; Treatment Outcome

To evaluate endovascular popliteal artery aneurysm repair using a an "off-label" abdominal endograft limb-module with nitinol-ring structure.. Retrospective observational study of 14 popliteal artery aneurysms in 12 male patients (mean age 76 years and median ASA grade 3) treated electively using the Anaconda™ endograft limb (Terumo Aortic) at a single teaching hospital. Eight limbs were treated percutaneously and 6 limbs required surgical arterial exposure. The mean popliteal artery aneurysm diameter treated was 3.6 cm (range 2.1-5.3 cm). Stent-graft diameters and lengths used were 10-15 and 60-140 mm, respectively. The median covered stented length was 218 mm (range 160-270 mm) and median duration of follow-up was 3.7 years. Outcomes assessed included technically successful aneurysm exclusion, primary patency, re-intervention and survival.. All patients had successful stent-graft deployment and aneurysm exclusion, with no early complications or mortality at 30 days. Primary stent-graft patency at 1, 3 and 4 years was 93%, 75%, and 64%. By 8 years, patency had declined with 29% (2/14) stent-grafts patent. 7/14 limbs occluded; 3 underwent re-intervention (2 surgical, 1 endovascular). There were no deaths related to the procedure. Freedom from re-intervention and survival at 1/5 years was 93%/84% and 93%/67%, respectively.. The Anaconda™ endograft limb for endovascular popliteal artery aneurysm repair offers good mid-term patency and acceptable long-term patency up to 4 years when compared with other grafts and open surgery. It may be considered in older comorbid patients unfit for surgery and can be performed percutaneously under local anaesthesia when anatomically feasible.

Topics: Aged; Aneurysm; Blood Vessel Prosthesis Implantation; Endovascular Procedures; Humans; Male; Popliteal Artery; Popliteal Artery Aneurysm; Retrospective Studies; Stents; Treatment Outcome; Vascular Patency

The feasibility of using a compressed interwoven Supera stent as a flow diverting device for popliteal aneurysms was recently demonstrated in patients. It is unclear, however, what the optimal flow diverting strategy is, because of the fusiform shape of popliteal aneurysms and their exposure to triphasic flow. To assess this flow diverting strategy for popliteal aneurysms, flow profiles and thrombus formation likelihood were investigated in popliteal aneurysm models.. Six popliteal aneurysm models were created and integrated into a pulsatile flow set-up. These models covered a bent and a straight anatomy in three configurations: control, single-lined and dual-lined Supera stents. Two-dimensional flow velocities were visualized by laser particle image velocimetry. In addition, the efficacy of the stent configurations for promoting aneurysm thrombosis was assessed by simulations of residence time and platelet activation.. On average for the two anatomies, the Supera stent led to a twofold reduction of velocities in the aneurysm for single-lined stents, and a fourfold reduction for dual-lined stents. Forward flow was optimally diverted, whereas backward flow was generally deflected into the aneurysm. The dual-lined configuration led to residence times of 15-20 s, compared to 5-15 s for the single stent configurations. Platelet activation potential was not increased by the flow diverting stents.. A compressed Supera stent was successfully able to divert flow in a popliteal aneurysm phantom. A dual-lined configuration demonstrated superior hemodynamic characteristics compared to its single-lined counterpart.

Topics: Alloys; Aneurysm; Humans; Popliteal Artery; Prosthesis Design; Stents; Treatment Outcome; Vascular Patency

To evaluate the efficacy of endovascular repair of popliteal artery aneurysms (PAAs) with a wire-interwoven nitinol stent.. This is a prospective, descriptive, and analytical study. From January 2016 to December 2018, 28 consecutive patients (29 lower limbs) were treated for a PAA with the deployment of the Supera stent (Abbott Vascular, Illinois). Twenty-three (79.3%) PAAs were asymptomatic; 6 (20.7%) presented with symptoms. The mean diameter and length of the aneurysm were 26.8 mm (20-40 mm) and 47.1 mm (23-145 mm) respectively. The primary endpoint was the prevention of embolic symptoms. The secondary endpoints were aneurysm exclusion, aneurysm diameter decrease, freedom from reintervention, and preservation of preoperative runoff vessels.. Technical success was 100%, with a median of 2.4 run-off vessels at completion angiography, without any loss of run-off vessels. A double Supera stent was deployed in 10 cases. At completion angiography, a median of 2.4 runoff vessels were present, without any loss of runoff vessels. The mean follow-up time was 24.3 (12-35) months. Primary endpoints were reached in 100% of the cases and vessels run off was preserved in all cases. In 2 PAAs, complete sac thrombosis was witnessed at 6-month follow-up, while at 12-month follow-up, it was seen in 10 of 29 (34.4%) limbs. In all the other cases the diameter of the aneurysm remained stable, with a freedom from sac enlargement of 100%. No fractures or stent thromboses were detected.. For endovascular repair of PAAs, the use of a thick interwoven-wire stent, that could work like a multilayer flow modulator showed encouraging mid-term results with no cases of stent fracture, occlusion or aneurysm increase.

Topics: Aged; Aged, 80 and over; Alloys; Aneurysm; Blood Vessel Prosthesis Implantation; Endovascular Procedures; Female; Humans; Male; Middle Aged; Popliteal Artery; Prospective Studies; Prosthesis Design; Stents; Time Factors; Treatment Outcome

To analyze the overall performance of flexible nitinol stents used to line chimney grafts (CGs) during chimney endovascular aneurysm repair (chEVAR) of pararenal pathologies.. A retrospective review was conducted of all 116 elective patients (mean age 74.3±7.2 years; 103 men) who underwent chEVAR with balloon-expandable Advanta V12/iCAST CGs in combination with the Endurant stent-graft between January 2009 and December 2017 at a single center. CG lining with a nitinol stent was electively performed in 43 target vessels of 32 patients. The Kaplan-Meier method was used to estimate the primary outcomes of CG patency and freedom from reintervention (FFR) at the patient level and according to the use of a stent to line the CG. Estimates are reported with the 95% confidence interval (CI). Adjusted odds ratios (ORs) were calculated to identify any confounding effect between the presence/absence of a stent lining or according to the number of CGs.. The mean radiological follow-up was 27.3 months (range 22.1-32.6). During this time, 8 CGs (4.7%) became occluded, 6 of them were lined with stents. Restoration of patency was possible in 3 of the 4 occluded stents that were associated with symptoms. First-year primary patency estimates were 96.9% (95% CI 92.5% to 100%) for the unlined group vs 77.1% (95% CI 58% to 95.3%; p=0.001) for the lined group, while FFR was 87.6% (95% CI 79.9% to 95.2%) vs 83.4% (95% CI 68.1% to 98.6%; p=0.82), respectively. Lining represented an independent risk factor for CG occlusion (OR 9.9, p=0.006).. CG lining performed mainly in angulated renal arteries during chEVAR was significantly associated with CG occlusion. These findings highlight the importance of not having the distal part of the CG impinge on the angulated segment of the target vessel.

Topics: Aged; Aged, 80 and over; Alloys; Aneurysm; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Endovascular Procedures; Female; Humans; Male; Prosthesis Design; Renal Artery; Retrospective Studies; Risk Factors; Stainless Steel; Stents; Treatment Outcome

Braiding of Nitinol micro wires is an established technology for the manufacturing of fine-meshed neurovascular implants for tortuous vessel geometries. Electropolishing of wires before the braiding process has the potential to improve the in vitro behaviour in terms of thrombogenicity and endothelial cell proliferation. In this study, we present the first in vitro investigation of braided electropolished/blue oxide Nitinol samples in a blood flow loop, showing a significantly lower activation of the coagulation pathway (represented by the TAT III marker) and a tendency towards reduced platelet adhesion. Furthermore, we applied the same surface treatment on flat disks and measured protein adhesion as well as endothelial cell proliferation. We compared our results to non-electropolished samples with a native oxide surface. While platelet deposition was reduced on electropolished/blue oxide surface, a significant increase of endothelial cell seeding was observed. Investigation of inflammatory marker expression in endothelial cells provided divergent results depending on the marker tested, demanding closer investigation. Surface analysis using Auger electron spectroscopy revealed a thin layer mainly consisting of titanium oxynitride or titanium oxide + titanium nitride as a potential cause of the improved biological performance. Translated to the clinical field of intracranial aneurysm treatment, the improved biocompatibility has the potential to increase both safety (low thrombogenicity) and effectiveness (aneurysm neck reconstruction).

Topics: Adsorption; Alloys; Aneurysm; Blood Coagulation; Blood Platelets; Blood Vessels; Cell Adhesion; Cell Proliferation; Coated Materials, Biocompatible; Elasticity; Electrochemistry; Endothelial Cells; Humans; Inflammation; Materials Testing; Nickel; Oxides; Patient Safety; Platelet Adhesiveness; Prostheses and Implants; Surface Properties; Titanium

Endovascular stents and flow diverter stents (FDS) have revolutionized the treatment of intradural aneurysms; however, the need for dual anti-platelet treatment (DAPT) limits their use and can cause additional issues. Therefore, there is a need to develop stent coatings that negate the need for DAPT.. Two different hydrophilic polymer coatings (HPC-I and HPC-II) were used to coat small nickel titanium plates to initially test the hydrophilic properties of these coatings when applied to nickel titanium. The plates were subsequently incubated with non-medicated whole blood from healthy volunteers for 10 min and stained with a CD61 immunofluorescent antibody that allows detection of adherent platelets. The coatings were applied to FDS wires and were again incubated with non-medicated whole blood from the same volunteers. Scanning electron microscopy was used to detect adherent platelets on the wire surface.. The HPC-II coating (1.12 ± 0.4%) showed a significantly lower CD61 +ve cell count (p ≤ 0.001) compared to both uncoated NiTi plates (48.61 ± 7.3%) and those with the HPC-I coating (mean 40.19 ± 8.9%). Minimal adherent platelets were seen on the FDS nickel titanium wires coated with the HPC-II compared to uncoated FDS under electron microscopy.. There is a significant decrease in the number of adherent CD61 +ve platelets on nickel titanium surfaces coated with the HPC-II coating compared to uncoated surfaces. The coating can be successfully applied to the wires of flow diverters. The results of this study are promising with regard to the development of new anti-thrombogenic endovascular devices.

Topics: Alloys; Aneurysm; Coated Materials, Biocompatible; Dura Mater; Fibrinolytic Agents; Humans; Hydrophobic and Hydrophilic Interactions; In Vitro Techniques; Materials Testing; Microscopy, Electron; Microscopy, Electron, Scanning; Platelet Adhesiveness; Stents; Surface Properties

Topics: Adult; Alloys; Aneurysm; Angiography; Embolization, Therapeutic; Endovascular Procedures; Humans; Incidental Findings; Prosthesis Design; Renal Artery; Self Expandable Metallic Stents; Treatment Outcome

Open aortic aneurysm repair in the setting of bilateral hypogastric aneurysms is technically challenging. We present a novel technique for open surgical repair for bilateral hypogastric aneurysms using the Gore hybrid vascular graft (GVHG; W. L. Gore and Associates Inc, Flagstaff, Arizona). The GVHG is an expanded polytetrafluoroethylene graft with a nitinol stent at 1 end designed for hemodialysis access. The GVHG has been also been used for aortic debranching and treatment of occlusive disease. We describe the first report using GVHG to repair hypogastric aneurysms.

Topics: Aged; Alloys; Aneurysm; Arteries; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Computed Tomography Angiography; Female; Humans; Iliac Aneurysm; Pelvis; Polytetrafluoroethylene; Prosthesis Design; Stents; Treatment Outcome

Endovascular treatment offers a great advantage in the management of main arteries stenoses. However, simultaneous presence of a group of anomalies may complicate the situation. Here we present a case of 21-year-old man with aortic coarctation. Radiographic imaging and angiography demonstrated aortic coarctation of the left-circumferential aortic arch, right-sided descending aorta, and Kommerell's diverticulum at the origin of right subclavian artery. These anomalies have rarely been reported to concurrently exist in the same case and the treatment is challenging. Percutaneous treatment for repair of aortic coarctation was successfully performed with deployment of self-expanding nitinol stents. Follow-up demonstrated the correction of blood pressure and improvement of the symptoms. It appears that deployment of self-expandable nitinol stents present a viable option for the management of coarcted aorta in patients having all or some of these anomalies together.

Topics: Abnormalities, Multiple; Alloys; Aneurysm; Angioplasty, Balloon; Aorta, Thoracic; Aortic Coarctation; Aortography; Cardiovascular Abnormalities; Computed Tomography Angiography; Deglutition Disorders; Diverticulum; Humans; Male; Prosthesis Design; Stents; Subclavian Artery; Treatment Outcome; Young Adult

A 60-year-old man was admitted for right knee pain provoked by an enlarging popliteal artery aneurysm (PAA) after endovascular therapy for thromboembolism in the right popliteal artery. The PAA was treated with implantation of a covered stent graft (Fluency(®)); however, acute thromboembolism occurred 6 months after the intervention. Therefore, we implanted a nitinol stent (S.M.A.R.T.(®)) in the proximal part of the covered stent where the major hinge point existed in addition to a stent fracture. No vascular event occurred during 4.5 years of follow-up.

Topics: Alloys; Aneurysm; Angiography; Coated Materials, Biocompatible; Endovascular Procedures; Humans; Male; Middle Aged; Popliteal Artery; Prosthesis Design; Stents; Tomography, X-Ray Computed; Vascular Patency

To assess the therapeutic outcome after endovascular repair of iliac arterial lesions (IALs) using a self-expandable Nitinol stent graft system.. Between July 2006 and March 2013, 16 patients (13 males, mean age: 68 years) with a self-expandable Nitinol stent graft. A total of 19 lesions were treated: nine true aneurysms, two anastomotic aneurysms, two dissections, one arteriovenous fistula, two type 1B endoleaks after endovascular aneurysm repair, one pseudoaneurysm, and two perforations after angioplasty. Pre-, intra-, and postinterventional imaging studies and the medical records were analyzed for technical and clinical success and postinterventional complications.. The primary technical and clinical success rate was 81.3% (13/16 patients) and 75.0% (12/16), respectively. Two patients had technical failure due to persistent type 1A endoleak and another patient due to acute stent graft thrombosis. One patient showed severe stent graft kinking on the first postinterventional day. In two patients, a second intervention was performed. The secondary technical and clinical success rate was 87.5% (14/16) and 93.8% (15/16). The minor complication rate was 6.3% (patient with painful hematoma at the access site). The major complication rate was 6.3% (patient with ipsilateral deep vein thrombosis). During median follow-up of 22.4 months, an infection of the aneurysm sac in one patient and a stent graft thrombosis in another patient were observed.. Endovascular repair of various IALs with a self-expandable Nitinol stent graft is safe and effective.

Topics: Aged; Alloys; Aneurysm; Blood Vessel Prosthesis Implantation; Endovascular Procedures; Female; Humans; Iliac Artery; Male; Middle Aged; Prosthesis Design; Retrospective Studies; Stents; Treatment Outcome

The degeneration of pancreaticoduodenal arcade vessels due to pancreaticoduodenal artery aneurysms is associated with celiac artery stenosis or occlusion. While technical advances have made it possible to treat pancreaticoduodenal arcade aneurysms (PDAA) and celiac artery stenosis by endovascular techniques, there is no consensus regarding their optimal treatment.. To treat pancreaticoduodenal arcade aneurysms (PDAA) by simultaneous coil embolization and celiac artery stenting, and propose indications for treating PDAA with celiac artery stenosis by this method.. We reviewed 11 patients who underwent transcatheter coil embolization (TCE) to treat PDAA. When the aneurysmal neck size was less than half of the short axis of the aneurysm we used packing only, when it was more than half of the short axis we undertook isolation. In the latter situation, when there was evidence of celiac artery stenosis, we performed celiac artery stenting using self-expandable stents.. Ten of the 11 patients (91%) presented with celiac axis stenosis due to median arcuate ligament compression. Coil-packing of the aneurysmal sac only, thus preserving the native arterial circulation, was done in five patients, another five underwent isolation by embolization of vessels distal and proximal to the PDAA with simultaneous stenting of the stenotic celiac axis, and one patient was treated by isolation only. One patient developed acute pancreatitis. There were no other complications and all aneurysms were successfully excluded. In one patient the celiac stent thrombosed after stopping the antiplatelet regimen.. TCE can be effective in patients with PDAA. In the presence of celiac artery stenosis, we recommend isolation of the aneurysms with simultaneous stenting of the stenotic celiac trunk using self-expandable stents.

Topics: Aged; Alloys; Aneurysm; Angioplasty; Celiac Artery; Constriction, Pathologic; Embolization, Therapeutic; Female; Humans; Iopamidol; Male; Middle Aged; Pancreas; Radiographic Image Enhancement; Stents; Treatment Outcome

An anomalous systemic artery originating from the descending thoracic aorta supplying the normal basal segments of the lower lobe of the left lung without sequestration is a rare congenital anomaly. The published surgical treatments include lobectomy, segmentectomy, anastomosis, and ligation. In addition, endovascular treatment with coils has been reported. A second-generation occluder, the Amplatzer Vascular Plug II (AVP II), has a central plug and two occlusion disks and a finer, more densely woven nitinol wire, thus enabling faster embolization. This published case is the first successful occlusion of an aneurysm of an anomalous systemic artery with the AVP II and fibered coils, with 10 months of follow-up.

Topics: Alloys; Aneurysm; Angiography; Aorta, Thoracic; Chest Pain; Embolization, Therapeutic; Equipment Design; Follow-Up Studies; Humans; Lung; Male; Middle Aged; Pulmonary Artery; Pulmonary Embolism; Septal Occluder Device; Tomography, Spiral Computed; Treatment Outcome

Thin film nitinol produced by sputter deposition was used in the design of microstents intended to treat small vessel aneurysms. Thin film microstents were fabricated by "hot-target" dc sputter deposition. Both stress-strain curves and differential scanning calorimetry curves were generated for the film used to fabricate stents. The films used for stents had an A(f) temperature of approximately 36 degrees C allowing for body activated response from a microcatheter. The 10 microm film was only slightly radio-opaque; thus, a Td marker was attached to the stents to guide fluoroscopic delivery. Thin film microstents were tested in a flow loop with and without nitinol support skeletons to give additional radial support. Stents could be compressed into and easily delivered with <3 Fr catheters. Theoretical frictional and wall drag forces on a thin film nitinol small vessel vascular stent were calculated, and the radial force exerted by thin film stents was evaluated theoretically and experimentally. In vivo studies in swine confirmed that thin film nitinol microstents could be deployed accurately and consistently in the swine cranial vasculature.

Topics: Alloys; Aneurysm; Animals; Blood Vessel Prosthesis Implantation; Intracranial Aneurysm; Stents; Swine

Large, symptomatic aneurysms of the cavernous internal carotid artery (ICA) can be successfully treated by a combination of aneurysm coiling and occlusion of the parent vessel.. We describe the use of an Amplatzer (AGA medical corporation, Plymouth, MA, USA) detachable nitinol vascular plug to occlude the ICA in four patients with symptomatic cavernous ICA aneurysms.

Topics: Aged; Alloys; Aneurysm; Angioplasty; Carotid Artery Diseases; Carotid Artery, Internal; Cohort Studies; Embolization, Therapeutic; Female; Humans; Middle Aged; Radiography

A 68-year-old woman with a left renal artery aneurysm underwent successful endovascular repair with the use of a commercial type self-expanding stent-graft. Complete aneurysm exclusion was achieved after stent-graft expansion. A side branch vessel was occluded after stent-placement, resulting in a small upper lobe renal perfusion defect. There were no other complications. The aneurysm remained excluded and its greatest diameter has been reduced from 2.6 cm to 1.95 cm, 10 months after treatment. Renal function remained normal.

Topics: Aged; Alloys; Aneurysm; Catheterization; Female; Humans; Polytetrafluoroethylene; Renal Artery; Stents

The objective of our study was to investigate the diagnostic accuracy of MRI and helical CT for endoleak detection.. Fifty-two patients underwent endovascular aneurysm repair with nitinol stent-grafts. Follow-up data sets included contrast-enhanced biphasic CT and MRI within 48 hr after the intervention; at 3, 6, and 12 months; and yearly thereafter. The endoleak size was categorized as < or = 3%, > 3% < or = 10%, > 10% < or = 30%, or > 30% of the maximum cross-sectional aneurysm area. A consensus interpretation of CT and MRI was defined as the standard of reference.. Of 252 data sets, 141 showed evidence for endoleaks. The incidence of types I, II, and III endoleaks and complex endoleaks was 3.2%, 40.1%, 8.7%, and 4.0%, respectively. The sensitivity for endoleak detection was 92.9%, 44.0%, 34.8%, and 38.3% for MRI, biphasic CT, uniphasic arterial CT, and uniphasic late CT, respectively. The corresponding negative predictive values were 91.7%, 58.4%, 54.7%, and 56.1%, respectively. The overall accuracy of endoleak detection and correct sizing was 95.2%, 58.3%, 55.6%, and 57.1% for MRI, biphasic CT, uniphasic arterial CT, and uniphasic late CT, respectively.. MRI is significantly superior to biphasic CT for endoleak detection and rating of endoleak size, followed by uniphasic late and uniphasic arterial CT scans. MRI shows a significant number of endoleaks in cases with negative CT findings and may help illuminate the phenomenon of endotension. Endoleak rates reported after endovascular aneurysm repair substantially depend on the imaging techniques used.

Topics: Aged; Aged, 80 and over; Alloys; Aneurysm; Female; Follow-Up Studies; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Postoperative Complications; Predictive Value of Tests; Prospective Studies; Sensitivity and Specificity; Statistics, Nonparametric; Stents; Tomography, Spiral Computed

Magnetic resonance imaging (MRI) is an established modality in clinical use but may be potentially underutilized to visualize and investigate biomaterials. As its use is totally contraindicated only for ferromagnetic devices, it was employed to visualize deployment, biofonctionality, healing, and biodurability of a commercially available endovascular device, namely the Medtronic-AVE AneuRx. The quality of the observations coupled with the absence of ionizing radiations are likely to make this technique an attractive imaging modality in the future.. The potential benefits of the MRI technique were investigated in a GE Vectra-MR 0.5T MRI for the Medtronic-AVE AneuRx endovascular prosthesis, under different conditions: undeployed i.e., inserted in the delivery cartridge as received from the manufacturer (step 1), deployed in a mock glass-aneurysm tube (step 2), and as a pathological explant harvested at the autopsy of a patient (step 3). The device was submitted to X-rays for examination in addition to MRI. At step 3, the device was further investigated with light microscopy and scanning electron microscopy (SEM) together with X-ray diffraction.. The device which was inserted and pleated in the delivery cartridge did not demonstrate any significant observation either in MRI or in X-rays. When it was deployed in the mock aneurysmal glass tube, light artefacts were associated with the T2 weighed FSE images around the Nitinol whereas X-rays gave images of indisputable interest. Similar results were noted using the explanted device. Very high contrasts were obtained with T1 whereas T2 images were almost defect free. The X-rays allowed to accurate imaging of the Nitinol skeleton but were poor to discriminate between the different tissues. Pathology observations using light microscopy were not really challenged, as the magnetic resonance imaging was performed using a 0.5T machine.. The benefits of magnetic resonance imaging as a quality control technique to examine an endovascular device within its cartridge remains ill defined. Similarly, the role of conventional X-rays is unknown. The observation of devices fully deployed in a mock aneurysmal glass-tube under MRI are potentially useful but X-rays images allowed better definition. The MRI examination of the explanted device does permit observations related to the healing of the device that might be obtained in vivo and, thus offers new avenues for the follow-up of implanted devices. The pathological investigations brought additional informations about the tissues and the corrosion of the Nitinol. However, it is unlikely that MRI will permit detailed analysis of the biomaterials and in particular the corrosion process of the stents.. These early observations of the follow-up of devices using MRI warrant further investigation. The absence of ionizing radiation with MRI makes this technique particularly attractive. As there is no emission of ionizing radiation associated with magnetic resonance, it is recommended that further investigation using this environment friendly technique for the follow-up of devices made of biomaterials that are MRI compatible.

Topics: Alloys; Aneurysm; Biocompatible Materials; Blood Vessel Prosthesis; Humans; Magnetic Resonance Imaging; Materials Testing; Models, Biological; Stents

The results of infra-inguinal intervention for atherosclerotic occlusive disease have not changed dramatically in the last 15 years despite the advent of many different designs of uncovered stents. "Plain old balloon angioplasty" remains the treatment of choice for short lesions (<3 cm) with good morphologic characteristics. Stents have improved suboptimal angioplasty results somewhat, but results in longer lesions >5 cm have remained poor in most series. Although there are no endografts currently approved for arterial use by the FDA, expanded polytetraflouroethylene (ePTFE) covered endoprostheses are available and their use in the femoropopliteal arteries can dramatically improve the results of endovascular treatment for longer lesions and allow one to treat vascular ruptures and aneurysms. In this article, we will review the published results for the use of endografts in the femoropopliteal arteries and describe what we believe to be the current indications for their use.

Topics: Alloys; Aneurysm; Angioplasty, Balloon; Arterial Occlusive Diseases; Embolism; Femoral Artery; Humans; Polytetrafluoroethylene; Popliteal Artery; Radiography; Stents; Vascular Patency

Topics: Alloys; Aneurysm; Blood Vessel Prosthesis Implantation; Coated Materials, Biocompatible; Equipment Failure; Female; Humans; Middle Aged; Reoperation; Stents; Subclavian Artery; Thoracic Outlet Syndrome; Treatment Outcome

To evaluate the success rates of the implantation of stent grafts in the treatment of peripheral aneurysms.. In 13 patients with 15 aneurysms at the common iliac artery (n = 6), external iliac artery (n = 1), hypogastric artery (n = 2), femoral artery (n = 2) or popliteal artery (n = 4), implantation of dacron-covered nitinol stents was performed. The patients were followed up for three to 20 months (mean, 8.8 months) with intravenous digital subtraction angiography, CT or colour-coded Doppler sonography.. In all cases, the aneurysm was successfully occluded after stent implantation. In one case with a popliteal aneurysm, kinking of the vessel caused thrombosis of the stent. The stent was successfully reopened. The aneurysm however, had to be surgically treated 9 months later. The primary and secondary patency rates at 6 months were 93% and 100%, respectively.. The method described might be an alternative therapy to surgery. There are some limitations in respect of treatment of popliteal aneurysms.

Topics: Adult; Aged; Alloys; Aneurysm; Equipment Design; Female; Femoral Artery; Follow-Up Studies; Humans; Iliac Artery; Male; Middle Aged; Polyethylene Terephthalates; Popliteal Artery; Postoperative Complications; Radiography; Stents; Time Factors

An iliac aneurysm developed after local lysis and balloon dilatation of the left iliofemoral arteries in a 66-year old male patient. This led to arterial embolism. A self-expanding Dacron-Nitinol vascular endoprosthesis was inserted without surgery. In this way, the aneurysm was isolated from the circulation.

Topics: Aged; Alloys; Aneurysm; Angiography; Angioplasty, Balloon; Blood Vessel Prosthesis; Combined Modality Therapy; Humans; Iliac Artery; Ischemia; Leg; Male; Polyethylene Terephthalates; Recurrence; Stents; Thrombolytic Therapy; Urokinase-Type Plasminogen Activator