Thrombin-soaked coils: estimation of thrombin dose.

Thrombin-soaked coils have been used as embolic agents for the treatment of various conditions. Intravascular injection of thrombin also has been used for thrombus formation; however, the effects of high doses of intravascular thrombin may be detrimental. In an in vitro experiment, the dose of thrombin associated with transcatheter use of thrombin-soaked steel coils was estimated. The 8 mm x 5 cm, 0.038-inch coils absorbed an overall average dose of 38.4 U (USP) of thrombin when soaked in a solution of 10,000 U of thrombin per 10 mL of saline. The same size coils absorbed an overall average dose of 71.6 U of thrombin when soaked in a concentration of 20,000 U of thrombin per 10 mL of solution. Maximum single-coil absorbed doses were 45.6 and 88.2 U for 1,000 and 2,000 U/mL, respectively. A plateau in thrombin absorption occurred after 1 minute of soaking. Absorption of thrombin was maximized by soaking the coils in a vertical orientation; almost no thrombin was absorbed when the coils were soaked in a horizontal position.     

可脱性弹簧圈栓塞治疗脑血管痉挛期颅内动脉瘤

目的　探讨可脱性弹簧圈在脑血管痉挛期 (4～ 14d)栓塞治疗颅内动脉瘤的方法及效果。方法　 2 0 0 4年 3～ 8月共栓塞颅内动脉瘤 14例 ,其中颈内动脉瘤 1例 ,后交通动脉瘤 8例 ,前交通动脉瘤5例 ,所有患者均在 4～ 14d内采用DCS MATRIX材料进行栓塞。结果　 11例栓塞 10 0 % ,2例栓塞 70 %～ 90 % ,1例栓塞 5 0 % ;其中有 6例发现有脑血管痉挛。结论　在脑血管痉挛期 ,血管内栓塞动脉瘤也是一种安全、微创、有效的治疗方法。     

电解可脱性微弹簧圈血管内栓塞颅内动脉瘤的临床研究

目的 总结以电解可脱性弹簧圈血管内栓塞治疗颅内动脉瘤的技术要点、并发症及其防治经验，并客观评价其治疗效果。方法 对136例颅内动脉瘤患者采用经皮股动脉穿刺行全脑选择性血管造影术，应用电解可脱性弹簧圈进行动脉瘤囊内栓塞；术后早期处理出血并有效的对症治疗。结果 成功栓塞136个动脉瘤，132例痊愈，4例死亡，病死率2．9％。动脉瘤腔100％闭塞者123个，95％闭塞者8个，90％闭塞者5个。术中并发动脉瘤破裂3例，脑血管痉挛7例；术后2例弹簧圈末端逸出。3例复发者经二次补充栓塞而治愈。全组出现与栓塞技术相关的并发症13例。术后随访6～54个月均无再出血。结论 对颅内动脉瘤采用电解可脱性弹簧圈进行血管内囊内栓塞疗效可靠；早期诊断、早期治疗、正确处理术中并发症、提高栓塞技术及积极有效的术后处理是减少术后并发症、提高治愈率的重要方法。     

Bronchial artery embolization with detachable coils for the treatment of haemoptysis. Preliminary experience

PURPOSE: This paper reports our early experience in the treatment of haemoptysis with embolization of the bronchial arteries using detachable coils. MATERIALS AND METHODS: Ten patients (mean age 45 years, range 23-83) with haemoptysis due to bronchoscopic biopsy of indeterminate lung nodules, lung cancer, tubercular bronchiectasis, cystic bronchiectasis or sarcoidosis underwent embolization of the bronchial arteries responsible for the bleeding using detachable coils. Patients were followed-up for a median of 14 months. RESULTS: In all patients the procedure halted the bronchial bleeding within 24 hours. Eight patients had no recurrence of haemoptysis. In one patient with lung cancer and another with sarcoidosis, haemoptysis recurred within 1-3 months due to recruitment of additional feeding arteries and to a missed large feeding artery originating from the subclavian artery, which required a new procedure. CONCLUSIONS: Use of detachable coils for embolization of bronchial arteries in patients with haemoptysis is advantageous since it eliminates the risk of migration typical of other embolic materials and enables rapid and permanent vessel occlusion.     

Aneurysmal rupture during embolization with Guglielmi detachable coils: causes, management, and outcome.

BACKGROUND AND PURPOSE: Aneurysmal rupture during endovascular treatment is one of the most feared complications of endovascular aneurysm therapy. The purpose of this study was to determine the frequency, causes, management, and outcome of aneurysmal rupture that occurred during treatment with Guglielmi detachable coils (GDCs) in an unselected series of patients with ruptured cerebral aneurysms. METHODS: Between July 1997 and December 2000, we treated 164 acutely ruptured cerebral aneurysms with GDCs. All charts were reviewed, and patients with aneurysmal rupture occurring during embolization were identified. RESULTS: Five patients had an intraprocedural aneurysmal rupture. In one patient, rupture was due to guidewire perforation of the wall. In two patients, the microcatheter itself perforated the aneurysm. In another two patients, rupture occurred during placement of the first coil. Endovascular packing was continued in all patients. One patient died as a result of the aneurysmal rupture. No negative long-term effects were observed in the remaining four patients. In summary, we observed intraprocedural aneurysmal rupture in 3% of our patients, with a mortality rate of 20% and no long-term morbidity. CONCLUSION: Aneurysmal rupture during endovascular treatment with GDCs is a rare event; clinical severity may be variable. Embolization of the aneurysm can be continued in most cases, and most patients with treatment-related subarachnoid hemorrhage survive without serious sequelae.     

一级微铜圈肾动脉栓塞的实验研究

目的 评价一级微铜圈在动物体内的栓塞性能和生物相容性.方法 用直径0.1 ～ 0.23 mm导电用铜丝(纯度99.9％)制成直径0.48 ～ 0.74 mm的一级微铜圈,经3F微导管释放栓塞兔肾动脉末梢支,于栓塞术后不同时间观察血管闭塞情况和病理学改变,同时对实验动物栓塞前后的实验室检查指标进行比较.结果 栓塞术后3d,1、2、4、6和12周,动脉造影血管管腔闭塞时可见到血栓形成.栓塞后4周,组织学检查均可见小动脉内微球,动脉周围有炎性反应,并可见肾实质梗死灶;栓塞术后,血清铜离子术后2周内较术前升高,差异有统计学意义(P＜0.05),术后4周与术前比较,差异无统计学意义(P＞0.05);肝、肾功能2周后恢复至术前水平.结论 自制一级微铜圈具有明确的栓塞效果和良好的生物相容性.     

Transarterial embolization of a direct carotid cavernous fistula with Guglielmi detachable coils.

Four patients underwent transarterial embolization of a carotid-cavernous fistula with Guglielmi detachable coils; in three cases as the initial form of treatment and in one case after treatment via transarterial balloon embolization failed. The fistulas were 2 to 3 mm in diameter on pretreatment angiograms. Complete obliteration was achieved in two patients; in the other two, minimal residual flow remained immediately after embolization but disappeared by follow-up angiography. One to four coils were used to occlude the fistulas. The internal carotid artery remained patent in all patients, and there were no complications.     

Infections related to coils used for embolization of arteries: review of the published evidence

The embolization of arteries with the use of coils has been an advance in the management of patients such as those at risk for aneurysm rupture. However, this procedure is not without complications. A systematic review was undertaken to evaluate the available evidence regarding infectious complications directly related to endovascular coil embolization. Seven case reports of patients who experienced infection related to coils used for embolization of arteries were discovered. Arteries embolized with coils in these patients were intracranial, intraabdominal, and intrathoracic, respectively, in four, two, and one case. Abscess formation in the area of coil placement (n = 6; 85.7%) was the most common infectious complication directly related to endovascular coil embolization. Staphylococcus aureus was the predominant isolated pathogen (n = 3; 42.9%). Other isolated pathogens included Salmonella species type D (n = 1; 14.3%), S. epidermidis (n = 1; 14.3%), Escherichia coli (n = 1; 14.3%), and Bacteroides fragilis (n = 1; 14.3%). Surgical procedures were performed in four of the seven patients described (57.1%), and three patients were treated with only the administration of antimicrobial agents. All reviewed patients were cured. Even though it may partially be a result of reporting bias, the scarcity of reports describing infections directly related to endovascular coils despite the increasing number of patients who received this treatment in various parts of the world suggests that infectious complications associated with this foreign endovascular material are very rare. However, the existence of the identified case reports suggests that clinicians should include coil-related infection in the differential diagnosis of patients with fever after this procedure.     

Interlocking detachable platinum coils,a controlled embolization device: Early clinical experience

Purpose: To present the early clinical experience of a new mechanically controlled-release embolization device<+>—<+>the interlocking detachable coil (IDC)—in complex embolization outside the head. Methods: IDCs were used only when conventional embolization techniques were considered too risky or unsafe. The coils consist of unfibered coiled platinum (0.012 inch), mechanically connected to a pusher wire and deployed through a Tracker 18 catheter. IDCs come in a range of diameters (2<+>–<+>8 mm) and lengths (1<+>–<+>30 cm). Results: A total of 87 IDCs were used for 27 procedures in 25 patients (mean 14.5 years) to occlude 31 arteries or vascular lesions. Control of the coil and its release were satisfactory and all coils were fully retrievable up to the point of deployment. Two IDC coils embolized inadvertently but were retrieved; there were no other complications. The IDC coils could not be satisfactorily placed in one high-flow arteriovenous (AV) fistula, and in another case there was a small residual fistula. Occlusion was produced in 29 of 31 lesions. Ancillary techniques were needed in 5 patients: temporary balloon occlusion in 2 and 0.038-inch coils in 3. Conclusion: The IDC coil is an effective device that allows controlled embolization to be performed, especially in aneurysms and in high-flow AV fistulas in children.     

Effect of iodinated contrast media on blood clotting

Recently, blood clot formation in catheters used for the injection of nonionic contrast media (CM) during angiography has been reported as being due to activation of hemostasis in the catheter. However, CM exhibit inhibitory properties regarding coagulation and platelet functions. The effect on blood clotting of iohexol, iopamidol, ioxaglate, diatrizoate, and ioxitalamate at a ratio of 10% v/v with nonanticoagulated human whole blood was evaluated using the kinetics of fibrinopeptide A (FpA) generation. Blood aliquots were taken every 2 minutes until blood clot occurred. Two groups of contrast media were identified: (1) iohexol and iopamidol, which increased the clotting time, and (2) ioxaglate, diatrizoate, and ioxitalamate, for which all clotting times were over 30 minutes and no FpA generation occurred.     

Single-center experience with TruFill platinum coils for the embolization of cerebral aneurysms

Endovascular coiling has become a powerful alternative to neurosurgical clipping of cerebral aneurysms. Apart from the Guglielmi Detachable Coil (GDC) (Boston Scientific, Galway, Ireland), there is limited published data about the newer generation of detachable platinum coils, e.g., TruFill (Cordis, Johnson and Johnson, Miami, Fl.). We report our initial clinical experience with the embolization of aneurysms by TruFill coils. Included in this retrospective study were 26 patients (age 55.4±14.5 years; 9 male, 17 female) with 28 aneurysms, 21 ruptured and 7 unruptured. All patients were treated exclusively by embolization with TruFill platinum coils. Immediate angiographic and 6-month angiographic follow-up results were documented. Acute clinical outcome was recorded. Of the 28 aneurysms, 16 (57%) were completely occluded by TruFill embolization, 11 (39%) were incompletely occluded with residual necks, and 1 (4%) was partially occluded as residual aneurysm. There were no aneurysmal ruptures during the procedures. Follow-up at 6 months after the procedure was available in 18 patients and 19 aneurysms. Of the 19 aneurysms, 2 of 12 initially completely occluded aneurysms (17%) and 1 of 7 aneurysms with initial residual necks (14%) showed recanalization at the 6-month follow-up. One recanalized aneurysm was subsequently recoiled with consequent residual neck and remained unchanged at the 1-year follow-up. Embolization by TruFill platinum coils has a comparable total aneurysmal occlusion rate to that with GDC. The mid-term reintervention rate is low, and will require verification by future long-term studies.     

Spinal metastases from renal cell carcinoma: effect of preoperative particle embolization on intraoperative blood loss

BACKGROUND AND PURPOSE: Surgical repair of spinal metastases from renal origin is often complicated by excessive bleeding. The purpose of this study was to assess the effect of preoperative particulate embolization on intraoperative blood loss. METHODS: Twenty spinal metastases from renal origin (17 patients) treated by preoperative embolization with polyvinyl alcohol particles were analyzed retrospectively. Surgical decompression was performed within 2 days after embolization. A control group of 10 patients with 11 spinal metastases of renal origin underwent surgery without embolization. The effect of preoperative embolization, of completeness of embolization, and of particle size on the estimated intraoperative blood loss was analyzed using nonparametric statistical tests. RESULTS: Complete embolization was achieved in 10 cases and partial embolization in the other 10. The estimated blood loss of 19 embolized and 11 control cases was available from the surgical report. Median intraoperative blood loss in 19 embolized lesions was 1500 mL (range, 300-8000 mL), compared with 5000 mL (range, 1440-15000 mL) in the control group. Even after partial embolization, blood loss (median, 2000 mL) was significantly lower than in the control group. No significant differences in estimated blood loss were noted between the use of particles smaller than 250 microm and those larger than 250 microm. No embolization-related permanent neurologic deficit or skin or muscle necrosis occurred. CONCLUSION: Preoperative embolization of spinal metastases of renal origin with polyvinyl alcohol particles is safe and might reduce intraoperative blood loss significantly. Even partial embolization seems to be effective.     

Effect of metrizamide on whole blood oxygen affinity.

The effects on whole blood oxygen affinity following addition to human blood of either ionic (diatrizoate) or non-ionic (metrizamide) contrast medium were investigated in vitro. No medium changed whole blood oxygen affinity. Solutions of metrizamide produced less changes in plasma pH than solutions of diatrizoate. This difference is explained by lower buffer capacity and lower osmolality of metrizamide solutions. Low osmolality gives less redistribution of anions between plasma and red cells and therefore less decrease in plasma pH.     

Venous sac embolization of pulmonary arteriovenous malformation: Preliminary experience using interlocking detachable coils

Purpose: To evaluate the indication and advantages of venous sac embolization of pulmonary arteriovenous malformations (PAVMs) using interlocking detachable coils (IDCs). Methods: We performed percutaneous embolization in 12 PAVMs in four patients using IDCs, initially placed in the venous sac or at the feeding artery to prevent systemic migration of additional coils. We placed the IDCs in the venous sac in PAVMs with the following vascular architecture: the draining vein was larger than the feeding arteries and both vessels were interposed with the venous sac or there were short feeding arteries. Results: Complete occlusion was achieved in all 12 PAVMs without significant complications. We deployed IDCs in the venous sac in eight PAVMs and in the feeding artery in four. Conclusion: Venous sac embolization may be beneficial in PAVMs with large out-flow vessels or short feeding arteries. IDCs are suitable for this procedure.