PURPOSE: Onyx has been successfully applied in the treatment of various neurovascular lesions. However, some experience is required to get accustomed to its unpredictable fluoroscopic visibility during injection. This in vitro study aimed to evaluate the characteristics of radiopacity change in a simulated embolization procedure. MATERIALS AND METHODS: Using a bench-top Onyx injection experiment simulating a typical brain arteriovenous malformation embolization, nine cycles of casting modes (continuous injection) and plugging modes (injection with intermittent pauses) were performed. Radiodensity of Onyx droplets collected from the microcatheter tip and the distal head portion of the microcatheter were measured as time lapsed. Distribution of droplet radiodensity (radiodensity) and distribution of radiographic grade (grade) were analyzed and compared by repeated measurements. RESULTS: Within-group analysis revealed no significant radiodensity change with time (P>0.05). The radiodensity was significantly higher in the casting mode than in the plugging mode (P<0.01). The lateral radiograph of the microcatheter showed higher radiopacity (P<0.01) and better evenness (P<0.01) in the casting mode than in the plugging mode. A significant difference in microcatheter attenuation (both radiographic grade mean and SD; P<0.01) was noted between the two modes. Radiodensity had a significant influence on the radiopacity and radiopacity evenness of the microcatheter. CONCLUSION: The radiopacity of the Onyx can vary significantly over time because of early precipitation of tantalum powder. Radiopacity decreased significantly during plugging modes, characterized by pauses between injections.
Arteriovenous Malformations ; Brain ; Head ; In Vitro Techniques* ; Tantalum

OBJECTIVE: To investigate the effects of the Arg-Gly-Asp polypeptedes (RGD) peptides-modified porous tantalum surface on osteoblasts morphology and expressions of osteogenesis factors, and to evaluate RGD peptides promotes junctura ossium of tantalum-bone interface in vivo. METHODS: RGD peptides of different concentrations (1 g/L, 5 g/L, and 10 g/L) were loaded to porous tantalum slices with a diameter of 10 mm and a thickness of 3 mm by physical absorption. The 3rd generation of MG63 cells were co-cultured with tantalum and divided into 4 groups: Ta-cells (control) group, 1 g/L cells/Ta/RGD group, 5 g/L cells/Ta/RGD group, and 10 g/L cells/Ta/RGD group. Porous tantalum compo-sites and osteoblasts-tantalum interface were observed by scanning electron microscopy. The adhesion rate of osteoblasts was detected and immunocytochemistry was used to detect the expressions of filamentous actin (F-actin), osteocalcin (OC) and fibronectin (FN). RESULTS: The scanning electron microscope (SEM) revealed that osteoblasts distributed on the surface of porous tantalum and secreted extracellular matrix on outside and inner of micro-pores. The osteoblasts adhesion rate on porous tantalum modified with RGD was higher than that in the unmodified porous tantalum at the end of 24, 48, and 72 hours. The best adhesion effect was got in 5 g/L cells/Ta/RGD group at hour 48 [(68.07±3.80) vs. (23.40±4.39), P<0.05]. The results of immunocytochemistry showed that the expressions intensity of F-actin, OC and FN in osteoblasts on porous tantalum modified groups with RGD were stronger than that in the unmodified groups, and the expressions of 5 g/L cells/Ta/RGD group were significantly higher than those in the 10 g/L group and 1 g/L group [OC: (18.08±0.08) vs. (15.14±0.19), P<0.05; (18.08±0.08) vs. (14.04±0.61), P<0.05. FN: (24.60±0.98) vs. (15.90±0.53), P<0.05; (24.60±0.98) vs. (15.30±0.42), P<0.05. F-actin: (29.20±1.31) vs. (24.50±1.51), P<0.05; (29.20±1.31) vs. (16.92±0.40), P<0.05]. Correspondingly F-actin in osteoblasts was showed in longitudinal arrangement, and the expressions intensity was stronger than those OC and FN. CONCLUSION The RGD peptides is beneficial to enhance adhesion of osteoblast, spreading and reorganization of cytoskeleton on porous tantalum surface and improve the interface morphology, further promoting osteoblasts-tantalum conjunctive interface osseointegration.
Cell Adhesion ; Oligopeptides ; Osteoblasts/physiology* ; Osteogenesis ; Tantalum

BACKGROUND: The Cordis coronary stent is a flexible, balloon expandable, radiopaque tantalum stent. Previous reports have shown excellent initial clinical outcomes. To our knowledge, there is no report of the long-term clinical outcomes. The intensely radiopaque tantalum may interfere with the angiographic assessment. We intended to evaluate long-term clinical and angiographic restenosis rates after successful implantation of the Cordis tantalum coronary stent. METHOD: Two hundred and eighty-five consecutive patients with 300 lesions were treated with 366 Cordis stents. An angiographic follow-up substudy was performed in 190 lesions ; 6 month follow-up angiograms were available in 167(88%). At follow-up, intravascular ultrasound(IVUS) was performed to (1) determine the pattern of restenosis and (2) to validate the quantitative coronary angiographic(QCA) caliper measurements. RESULTS: IVUS and QCA caliper measurement of minimal luminal diameter correlated reliably (r=0.767, p<0.001). The QCA analysis detected diffuse in-stent restenosis more reliably than focal in-stent restenosis(p<0.01). The overall angiographic restenosis rate was 19%, The factors affecting angiographic restenosis were post-stent minimum lumen diameter, type C lesion, and reference vessel size. CONCLUSION: We concluded 1) The angiographic restenosis rate of Cordis stent was comparable to that of other slotted-tube stent. 2) The QCA caliper method is reliable for the assessment of Cordis in-stent restenosis, especially in the detection of diffuse in-stent restenosis. However, QCA may miss focal in-stent restenosis only detectable by IVUS
Coronary Artery Disease ; Follow-Up Studies ; Humans ; Phenobarbital ; Stents* ; Tantalum*

Incorrect treatment for femur head necrosis can cause collapse of femoral head and tresult in severe harm for the patients (especially for the patient with middle-aged and young). The structure and mechanics characteristics of tantalum rod is similar to bone tissue, it higher strength and can adapt the internal environment of organism, so it has a large potency in treating femur head necrosis. Treatment of early femur head necrosis with tantalum rod implanting had alreadly widey applied at home and abroad, the method has the advantages of simple operation, little risk, less complication and beseems the patient with stage I - II of ARCO. But reasons that the difficult diagnosis of early femur head necrosis, localized effect of tantalum rod, different experience of medical worker,caused the contentions about effect of tantalum rod implanting. With development of science, tantalum rod implanting combined with correlative biotechnology should raise the effect in treating femur head necrosis.
Femur Head Necrosis ; surgery ; Humans ; Prostheses and Implants ; Tantalum ; Treatment Failure

PURPOSE: We noted that in a catheter, glue-lipiodol mixtures (GLM) prematurely turned into a cast duringembolization of brain arteriovenous maliformation, and to avoid this problem, added tungsten to GLM. The reactiontime and hardness of GLM were then evaluated in vitro. MATERIALS AND METHODS: Six lots of Lipiodol (Nos.97LU009A, 96LU018A, 96LU017A, 96LUollA and 95Lu020A)(Laboratoire Guerbet, Cedex, France) and three lots HistoacrylBlue (2/7121, Ex. Date 03/99 (993);2/6263, 06/98 (986);2/6132 03/98 (983))(B. Brown, Melsungen, Germany) weremixed in a 5cc bottle at concentrations of 25-50%(glue:lipiodol=1:1 to 1:3) and observed for two weeks. Thehardness of polymerized GLM was classified as liquid, gel, semi-solid or solid. After the addition of tungsten ortantalum powder (0.2gm) and a drop of blood to GLM, different series of experiments were performed. pH wasmeasured in distilled water mixed with tungsten of tantalum(0.1 to 0.5 gm). RESULTS: At a concentration of 50%,most GLM turned into solid casts within 48 hours;at one of 25%, most GLM gelled within 24hrs. At concentrations of28 and 33%, hardness was between that of a solid and that of a gel. After the addition of tungsten to 50% and 25%GLM, this remained in a liquid state until two weeks later, regardless of lipiodol products. In 5cc distilledwater with 0.1 to 0.5 gm tungsten, pH changed from 3.5 to 2.6, and on the addition of tantalum from 6.4 to 5.7.The addition of blood to the mixture immediately turned the cast solid at a GLM concentration of 50%, andsemi-solid at one of 25%. CONCLUSION: The reaction time of GLM differed according to the lot number of lipiodol.The addition of tungsten seemed to prevent premature cast formation by decreasing pH;the mechanism was similar tothat observed when acetic acid was added.
Acetic Acid ; Brain ; Catheters ; Ethiodized Oil ; Hardness ; Hydrogen-Ion Concentration ; Polymers ; Reaction Time ; Tantalum ; Tungsten ; Water

BACKGROUND: Systemic anticoagulation therapy has been recommended to prevent subacute thrombosis after intracoronary stening. Recent data, however, suggest that antiplatelet therapy might be an effective alternative to anticoagulation therapy. We evaluated the effect of antithrombotic regimens on subacute thrombosis and short-term clinical course after successful implantation of Cordis coronary stent, which is a flexible, balloon expandable, radiopaque tantalum stent. METHOD: Two hundred and seventy-five consecutive patients with 290 lesions were treated with 356 Cordis stents implantation. According to post-stent antithrombotic regimen, patients were divided into three groups ; 165 patients with 175 lesions received aspirin 200mg/day, ticlopidine 500mg/day and warfarin for one month(Group 1), 66 patients with 69 lesions received aspirin and ticlopidine(Group 2) and 44 patients with 46 lesions received aspirin alone(Group 3) after successful Cordis stenting. RESULTS: The overall procidural success rates were 97.7% in group 1, 98.6% in group 2 and 100% in group 3. More than 65 percents of the patients were eligible for elective stenting aspirin, ticlopidine and warfarin, 0% in patients with aspirin and ticlopidine, and 6.8% in patients assigned to the treatment with aspirin alone. CONCLUSION: The Cordis coronary stent is an effective endovascular stent in various clinical indications including unstable angina and acute myocardial infarction. Antiplatelet therapy using aspirin and ticlopidine after successful Cordis coronary stenting is promising alternative to anticoagulation therapy to overcome the drawbacks of stenting. However, post-stent antithrombotic therapy with aspirin alone is associated with significant rate of stent thrombosis.
Angina, Unstable ; Aspirin ; Coronary Artery Disease ; Humans ; Korea* ; Myocardial Infarction ; Stents* ; Tantalum ; Thrombosis ; Ticlopidine ; Warfarin

In an attempt to evaluate cranioplasty, author reviewed 53 cases of head injuries with cranial defect repaired by cranioplasty. Materials used for cranioplasty were acrylic resin in 42 cases, tantalum in 6 cases and iliac bone in 5 cases. Adequate follow-up observations were obtained in all cases for at least 4 years. The results were as follows; 1) The majority of head injuries were caused by vehicle accident. 2) The majority of skull defects were in the frontal and parietal bones. 3) The interval between primary craniectomy and secondary cranioplasty was from 3 to 4 months in the majority of cases and cranioplasty was performed after fixation of permanent neurologic defect. 4) The indications for the cranioplasty were based upon criteria recommended by Grant and Norcross. 5) Postoperative complications were observed in 3 cases(5.7%).
Craniocerebral Trauma ; Financing, Organized ; Follow-Up Studies ; Parietal Bone ; Postoperative Complications ; Skull ; Tantalum

OBJECTIVETo investigate a new method for the treatment adult early femur head necrosis in order to avoid further collapse and necrosis and improve the clinical symptoms.

METHODSFrom January 2009 to June 2010, 10 hips of 9 patients, including 7 males and 2 females, aged from 29 to 63 years old (averaged 44.1), with femur head necrosis were treated with implantation of the tantalum screw. The X-ray film, CT scan and MRI were performed before operation. According to Steinberg staging, stage I was in 1 case (1 hip), stage II a in 4 cases(5 hips), stage II b in 4 cases (4 hip). With the C-arm X-ray conducted guide, wire was drilled into the center of femur head necrosis regions from the greater trochanter bottom, hollow bodkin enlarged marrow along the guide wire, scraped necrosis sequestrum, transplanted bone if necessary,then implantated the appropriate tantalum screw to prop up the articular surface. The patients were followed up at 3rd, 6th, 9th month postoperatively, the clinical effects were evaluated according to the JOA criteria, and the changes of the femoral head were observed by X-rays.

RESULTSThe mean operative time was 50 min (ranged from 40 to 60 min); the mean blood loss was 80 ml (ranged from 60 to 100 ml). There was no complications, such as postoperative infection, fracture, deep vein thrombosis and so on. All patients were followed up more than 9 months. No aggravation in collapse and necrosis were found by regular X-ray examination. Post-operative JOA score increased month by month. JOA scores increased obviously from preoperative (31.30 +/- 19.63) to (54.10 +/- 13.20), (69.90 +/- 15.04), (87.00 +/- 8.83) at the 3,6,9 months after operation, respectively.

CONCLUSIONThe tantalum screw implantation is simple and effective for the treatment of adult early femur head necrosis, and can effectively avoid collapse of necrotic area, the results were satisfactory in the near future.

Adult ; Bone Screws ; Female ; Femur Head Necrosis ; surgery ; Humans ; Male ; Middle Aged ; Prosthesis Implantation ; Tantalum

PURPOSE: To evaluate the effectiveness of core decompression using a tantalum trabecular metal system for treatment of early stage osteonecrosis of the femoral head, with a minimum follow-up of 1 year and a maximum follow-up of 5 years. MATERIALS AND METHODS: Between January 2003 and August 2007, a retrospective analysis was conducted on 46 femoral heads in 36 patients (9 males and 27 females) underwent core decompression using a tantalum trabecular metal system. The mean duration of follow-up was 26 months (minimum, 1 year; maximum, 5 years). The ARCO classification system was used. The mean age of the patients was 42.9 years. The conversion to total hip arthroplasty due to aggravating hip pain was defined as a clinical failure. RESULTS: At an average of 12 months, 18 patients (21 hips) were converted to THR. No conversion to THR in occurred in stages IA or IIA. In Stage IB, one-half of the medial lesion and all of the lateral lesions were converted to THR. One of 11 medial lesions and all of the lateral lesions in stage IC were converted to THR; 2 of 3 medial lesions and all of the lateral lesions in stage IIB were converted to THR. In stage IIC, 6 of 8 lateral lesions were converted to THR, but the central lesions were not converted. All of the lateral lesions in stage IIIC were converted to THR. CONCLUSION: The higher stage of ARCO classification and the more lateral position of the lesion, the greater the failure rate of the tantalum trabecular metal system. Conversion to THR from a failed tantalum trabecular system developed within 12 months postoperatively. The tantalum trabecular metal system is a useful treatment for osteonecrosis of the femoral head with a lower stage of ARCO classification and a medial location of the lesion.
Artemisinins ; Arthroplasty ; Decompression ; Follow-Up Studies ; Head ; Hip ; Humans ; Male ; Naphthoquinones ; Osteonecrosis ; Retrospective Studies ; Tantalum

BACKGROUND: Balloon angioplasty of ostial left anterior descending coronary artery lesions has been associated with high rate of acute complications and late restenosis. Recently, coronary stenting has been proposed as one of effective treatment modalites of ostial left anterior descending artery lesions. METHODS: To evaluate the effects of stent design on the development of late restenosis, we retrospectively analyzed the efficacy of slotted tube stent implantation (40 patients, Palmaz-Schatz stent) and coil stent implantation (15 patients, tantalum Cordis stent) of ostial left anterior descending artery stenosis. Six-month angiographic follow-up data were obtained in 31 patients (82%) with slotted tube stent implantation and 12 patients (86%) with coil stent implantation. Angiographic restenosis was defined as > or = 50% diameter stenosis. RESULTS: Angiographic resten-osis rate was significantly lower in slotted tube stent implantation (32%) than in coil stent implantation (67%) (p<0.05). Target lesion revascularization rate of slotted tube stent implantation was significantly lower (26%) than that of coil stent implantation (57%) (p<0.05). CONCLUSIONS: Coil stent implantation of ostial left anterior descending artery lesions was associated with higher late restenosis compared with slotted tube stent impla-ntation. In conclusion, slotted tube stent implantation might be considered for ostial left anterior descending artery lesions to improve late clinical outcomes.
Angioplasty, Balloon ; Arteries ; Constriction, Pathologic ; Coronary Artery Disease ; Coronary Stenosis* ; Coronary Vessels* ; Follow-Up Studies ; Humans ; Retrospective Studies ; Stents* ; Tantalum