Detection of microemboli distal to cerebral aneurysms before and after therapeutic embolization.

PURPOSE Recently developed interventional radiologic techniques, such as embolization with platinum coils, may induce thrombus formation within an aneurysm. The aim of the present study was to investigate the frequency of microemboli distal to untreated and treated cerebral aneurysms. METHODS Among a total of 110 patients treated with platinum coil embolization, 35 patients (27 women and eight men, aged 50+/-10 years) who were at high risk of ischemic complications underwent emboli detection with a transcranial Doppler sonographic monitoring system. All patients were studied before and after coil embolization. The aneurysms were located at the internal carotid artery (n=14), the basilar artery (n=10), the middle cerebral artery (n=7), or the vertebral artery (n=4). Twenty-nine (85%) of 35 patients were monitored within 6 hours of the completion of treatment. RESULTS Microemboli distal to the aneurysm were not detected in any of the patients before treatment. Microemboli were detected in 11 patients (31%) after embolization (mean, 16+/-21 per hour; range, 1-74 per hour). Microemboli were detected in five (71%) of seven patients in whom ischemic complications occurred after treatment, but in only six (21%) of 28 asymptomatic patients. This difference was statistically significant. The rate of occurrence of emboli in patients with ischemic complications (23+/-30 emboli per hour) was higher than in asymptomatic patients (10+/-7 emboli per hour), but this difference was not statistically significant. CONCLUSION Microemboli were detected significantly more often in patients who suffered from cerebral ischemia after coil embolization of an intracranial aneurysm. This observation supports the definition of a high-risk group of patients with incomplete embolization or with a large-diameter, broad-neck aneurysm. The early detection of microemboli after treatment may be an indicator for excessive intraaneurysmal thrombus formation and could influence the decision for prophylactic treatment with heparin or aspirin.

[1]  J. Dion,et al.  Medical management in the endovascular treatment of carotid-cavernous aneurysms. , 1996, Journal of neurosurgery.

[2]  R. Higashida,et al.  Endovascular treatment of basilar tip aneurysms using electrolytically detachable coils. , 1996, Journal of neurosurgery.

[3]  S. Davis,et al.  Cerebral Microemboli in Atrial Fibrillation Detected by Transcranial Doppler Ultrasonography , 1996 .

[4]  A. Molyneux,et al.  Histological findings in giant aneurysms treated with Guglielmi detachable coils. Report of two cases with autopsy correlation. , 1995, Journal of neurosurgery.

[5]  F. Moll,et al.  Detection of cerebral microemboli by means of transcranial Doppler monitoring before and after carotid endarterectomy. , 1995, Stroke.

[6]  K. Lees,et al.  Differentiation Between Gaseous and Formed Embolic Materials In Vivo: Application in Prosthetic Heart Valve Patients , 1994, Stroke.

[7]  M. Kupersmith,et al.  Endovascular treatment of giant aneurysms which cause visual loss. , 1994, Ophthalmology.

[8]  K. Lees,et al.  Coagulation Activity and Emboli Counts in Patients With Prosthetic Cardiac Valves , 1994, Stroke.

[9]  K. Lees,et al.  Prevalence and Characteristics of Intracranial Microemboli Signals in Patients With Different Types of Prosthetic Cardiac Valves , 1994, Stroke.

[10]  H. Steinmetz,et al.  Silent cerebral embolism caused by neurologically symptomatic high-grade carotid stenosis. Event rates before and after carotid endarterectomy. , 1993, Brain : a journal of neurology.

[11]  J. Hodes,et al.  Selective endovascular treatment of 71 intracranial aneurysms with platinum coils. , 1993, Journal of neurosurgery.

[12]  D. Bachman.  Microscopic air embolism during cerebral angiography , 1993, The Lancet.

[13]  L. Guterman,et al.  Endovascular treatment of cerebral aneurysms. Diagnosis and treatment. , 1993, Clinical neurosurgery.

[14]  F Viñuela,et al.  Endovascular treatment of posterior circulation aneurysms by electrothrombosis using electrically detachable coils. , 1992, Journal of neurosurgery.

[15]  H. Kikuchi,et al.  Selection and combination of various endovascular techniques in the treatment of giant aneurysms. , 1992, Journal of neurosurgery.

[16]  D. Kühne,et al.  Strategies of Endovascular Treatment of Large and Giant Intracranial Aneurysms , 1992 .

[17]  V. Macellari,et al.  Electrothrombosis of saccular aneurysms via endovascular approach. Part 1: Electrochemical basis, technique, and experimental results. , 1991, Journal of neurosurgery.

[18]  G. Duckwiler,et al.  Electrothrombosis of saccular aneurysms via endovascular approach. Part 2: Preliminary clinical experience. , 1991, Journal of neurosurgery.

[19]  J A Zivin,et al.  Detection of arterial emboli using Doppler ultrasound in rabbits. , 1991, Stroke.

[20]  L R Sauvage,et al.  Detection of middle cerebral artery emboli during carotid endarterectomy using transcranial Doppler ultrasonography. , 1990, Stroke.

[21]  J. Linley,et al.  The detection of microemboli in the middle cerebral artery during cardiopulmonary bypass: a transcranial Doppler ultrasound investigation using membrane and bubble oxygenators. , 1987, The Annals of thoracic surgery.