The postoperative neurological complications is associated with intraoperative cerebral emboli, which results from extracorporeal circulation and operation. It can effectively reduce the incidence of neurological complications with ultrasonic radiation. In fluids, a particle will change it's motion trail when it is acted by the radiation force generated by the ultrasound. This article mainly discuss how to shielding emboli with ultrasound. The equipment can transmit phased ultrasonic signals, which is designed on a FPGA development board. The board can generate a square wave, which is converted into a sine wave through a power amplifier. In addition, the control software has been developed on Qt development environment. The result indicates it's feasible to shielding emboli with ultrasonic radiation force. This article builds a strong foundation for the future research.
Humans ; Intracranial Embolism ; diagnostic imaging ; prevention & control ; Intraoperative Complications ; prevention & control ; Postoperative Complications ; prevention & control ; Ultrasonics ; instrumentation ; Ultrasonography

OBJECTIVESTo study the efficacy of proximal embolic protection device in preventing intracranial artery embolization during carotid artery stenting (CAS) and to evaluate its security and maneuverability.

METHODSFrom October 2007 to July 2008, 23 patients with carotid artery stenosis who were suitable for surgical therapy according to the standards of NASCET or ACAS were enrolled in this clinical research. Among them 19 patients (82.6%) were symptomatic, 6 patients (26.1%) with 50%-70% stenosis and 17 cases (73.9%) with > 70% stenosis. All the patients received carotid angioplasty and stenting under the protection of MO. MA system (one kind of proximal embolic protection device). We recorded the cerebral ischemic time during the procedure and observed neurologic events within 30 days.

RESULTSAll the procedures were performed successfully, the mean carotid artery blocking time was (5.3 +/- 1.2) min. No death or stroke occurred during perioperative period. Two cases of patients developed transient loss of consciousness combined with contralateral limb convulsion, while the common carotid artery was occluded by balloon. Two cases of patients developed bradycardia, sustained 6 hours and 1 week. Plaque debris in the withdrawal blood from carotid artery were found in 9 cases. At 30-day follow-up after CAS, TIA occurred in 1 case, new contralateral stroke occurred in 1 case, the incidence of 30-day stroke and death rate was 4.3%.

CONCLUSIONThe application of proximal embolic protection device in CAS procedure for preventing neurologic complications is safe and effective, especially for severe stenosis and unstable plaque in carotid artery stenting.

Aged ; Aged, 80 and over ; Angioplasty, Balloon ; instrumentation ; methods ; Carotid Stenosis ; surgery ; Embolic Protection Devices ; Female ; Follow-Up Studies ; Humans ; Intracranial Embolism ; etiology ; prevention & control ; Male ; Postoperative Complications ; prevention & control ; Stents ; Treatment Outcome

BACKGROUND: The etiology of cardioembolic stroke in Korea tends to be different from western countries. This study is to assess the current trend in the etiology and prevention of cardioembolic stroke in Korea. METHODS: We reviewed the medical records of patients with cardioembolic stroke retrospectively from 1998 to 2003. The following items were examined: type of cardioembolic source, previous anticoagulation or antiplatelet therapy, previous stroke, insight of the heart disease, and the International Normalized Ratio (INR) value of prothrombin time (PT) on arrival. RESULTS: The cardioembolic sources of 226 patients were found to be of non-valvular atrial fibrillation in 100 (44.2%), a left ventricle regional wall motion abnormality (LV RWMA) in 45 (19.9%), rheumatic heart disease (RHD) in 34 (15.1%), patent foramen ovale in 18 (8.0%), left atrial appendage thrombi in 11 (4.9%), prosthetic valve in 10 (4.4%), dilated cardiomyopathy in 5 (2.2%), and recent myocardial infarction in 3 (1.3%). In 179 patients with no previous stroke, primary prevention was made in 52 (66.7%). Twenty-five (53.2%) out of 47 patients with stroke history were under secondary prevention. Among 39 patients who developed stroke in spite of anticoagulation, PT INR values of 27 (69.3%) were below 2.0. Proportions of RHD and LV RWMA were decreased and increased respectively. The rate of primary prevention, anticoagulation as secondary prevention, and adequate anticoagulation were also increased. CONCLUSIONS: The etiology of cardioembolic stroke in Korea seems to be changing according to the pattern of western countries. Many physicians are beginning to recognize the need for prevention of cardioembolism but more action is needed.
Atrial Appendage ; Atrial Fibrillation ; Cardiomyopathy, Dilated ; Foramen Ovale, Patent ; Heart Diseases ; Heart Ventricles ; Humans ; International Normalized Ratio ; Intracranial Embolism ; Korea ; Medical Records ; Myocardial Infarction ; Primary Prevention ; Prothrombin Time ; Retrospective Studies* ; Rheumatic Heart Disease ; Secondary Prevention ; Stroke*

OBJECTIVETo report the initial application of brain protection device in the dilatation and stenting of atherosclerotic stenosis of the carotid and vertebral artery.

METHODSEighteen patients with 21 atherosclerotic stenoses of the carotid or vertebral artery underwent dilatation and/or stenting with brain protection device (filterwire or angioguard). The clinical results were summarized and the indispensability and feasibility of the device was discussed.

RESULTSWith the aid of brain protection device, endovascular dilatation and (or) stenting were performed in all the patients with 21 stenoses of the carotid or vertebral artery. The interventional manipulation was successful and no complications occurred.

CONCLUSIONSBrain protection device is helpful to decrease the embolic complication caused by atherosclerotic plaque and thromboembolus and to increase the security of interventional therapy, during the dilatation and/or stenting of stenosis of the carotid or vertebral artery.

Adult ; Aged ; Angioplasty, Balloon ; adverse effects ; methods ; Carotid Stenosis ; therapy ; Female ; Follow-Up Studies ; Humans ; Intracranial Embolism ; etiology ; prevention & control ; Male ; Middle Aged ; Protective Devices ; Stents ; adverse effects ; Vertebrobasilar Insufficiency ; therapy

OBJECTIVE: The aim of this study was to examine the incidence of ischemia during protected carotid artery stenting (CAS) as well as to compare the protective efficacy of the balloon and filter devices on diffusion-weighted MR imaging (DWI). MATERIALS AND METHODS: Seventy-one consecutive protected CAS procedures in 70 patients with a severe (> 70%) or symptomatic moderate (> 50%) carotid artery stenosis were examined. A balloon device (PercuSurge GuardWire) and a filter device (FilterWire EX/EZ, Emboshield) was used in 33 cases (CAS-B group) and 38 cases (CAS-F group) to prevent distal embolization, respectively. All the patients underwent DWI within seven days before and after the procedures. The number of new cerebral ischemic lesions on the post-procedural DWI were counted and divided into ipsilateral and contralateral lesions according to the relationship with the stenting side. RESULTS: New cerebral ischemic lesions were detected in 13 (39.4%) out of the 33 CAS-Bs and in 15 (39.5%) out of the 38 CAS-Fs. The mean number of total, ipsilateral and contralateral new cerebral ischemic lesion was 2.39, 1.67 and 0.73 in the CAS-B group and 2.11, 1.32 and 0.79 in the CAS-F group, respectively. No statistical differences were found between the two groups (p = 0.96, 0.74 and 0.65, respectively). The embolic complications encountered included two retinal infarctions and one hemiparesis in the CAS-B group (9.09%), and one retinal infarction, one hemiparesis and one ataxia in the CAS-F group (7.89%). There was a similar incidence of embolic complications in the two groups (p = 1.00). CONCLUSION: The type of distal protection device used such as a balloon and filter does not affect the incidence of cerebral embolization after protected CAS.
Adult ; Aged ; Aged, 80 and over ; *Balloon Occlusion ; Blood Vessel Prosthesis Implantation/*instrumentation ; Brain Ischemia/*pathology ; Carotid Stenosis/*surgery ; *Diffusion Magnetic Resonance Imaging ; Endarterectomy, Carotid/adverse effects/methods ; Female ; Humans ; Intracranial Embolism/prevention & control ; Male ; Middle Aged ; Paresis/etiology ; Retinal Artery Occlusion/etiology ; Severity of Illness Index ; *Stents