Cerebral vasospasm is the most common cause of morbidity and mortality in patients admitted to the hospital after suffering aneurysmal subarachnoid hemorrhage (SAH). The early surgical removal of subarachnoid clots and irrigation of the basal cisterns have been reported to reduce the incidence of vasospasm. In contrast to surgery, the endovascular treatment of aneurysms does not allow removal of subarachnoid clots.
View Article and Find Full Text PDFInterv Neuroradiol
November 1997
Ion implantation and protein-coatings were utilized to alter the surface properties (endothelial cellular adhesion) and enhance the thrombogenicity of Guglielmi detachable coils (GDCs) for endovascular treatment of cerebral aneurysms. These modified GDCs were compared with standard GDCs in the treatment of experimental swine aneurysms. Standard GDCs and ion-implanted protein coated GDCs were used to treat 32 aneurysms in 16 swine.
View Article and Find Full Text PDFPurpose: To perform in intra-arterial dose escalation study of carboplatin based on hemispheric blood-flow estimation in patients with recurrent malignant glioma. The primary purpose was to determine the maximally tolerated intra-arterial dose.
Methods And Patients: Methods included: 1) selective intra-arterial delivery performed with modern microcatheters, 2) pulsatile infusion, and 3) dosage based on local cerebral blood-flow estimation (middle cerebral artery 60%, anterior cerebral artery 20%, posterior cerebral artery 15%, and anterior choroidal artery 5% of the hemispheric blood-flow).
To furnish greater specificity in the analysis of cerebrospinal fluid from patients suspected of having multiple sclerosis, we studied the sensitivity and efficiency of indices and formulas used to calculate intrathecal IgG synthesis in a group of 49 patients with clinically defined multiple sclerosis, using cutoff values based on preestablished levels of specificity (75 and 90%), and compared the findings to those for a control group of patients with other neurological diseases. The best results were obtained with the indices and formulas based on computer models of brain-blood barrier function set forth most recently, namely Reiber's formula and Ohman's index, which had the highest specificity with the least loss of sensitivity.
View Article and Find Full Text PDFIntroduction: Epidural arterio-venous fistulae are a little known clinical condition. They are probably commoner than is thought, since diagnosis and angiographic demonstration are difficult.
Clinical Case: We present the case of a 49 year old man with the clinical features of chronic myelo-radiculopathy with episodes of intermittent medullary claudication.
A prospective study was designed to evaluate clinical outcome in a series of 100 consecutively treated patients who underwent endovascular embolization of 104 intracranial aneurysms using Guglielmi detachable coils (GDCs). Midterm clinical outcome (2-6 years, average 3.5 years) was obtained for 94 patients and was classified according to a modified Glasgow Outcome Scale.
View Article and Find Full Text PDFObjective: Complete anatomic obliteration remains difficult to achieve with endovascular treatment of wide-necked aneurysms using Guglielmi detachable platinum coils (GDCs). Ion implantation is a physicochemical surface modification process resulting from the impingement of a high-energy ion beam. Ion implantation and protein coating were used to alter the surface properties (thrombogenicity, endothelial cellular migration, and adhesion) of GDCs.
View Article and Find Full Text PDFThis study was performed to investigate the utility of transcranial color Doppler sonography in evaluating adult cerebral arteriovenous malformations. Twelve patients with such malformations underwent sonography. Spectral Doppler sonographic assessment included peak systolic velocity, end diastolic velocity, and resistive index within the intracranial and extracranial vessels.
View Article and Find Full Text PDFAJNR Am J Neuroradiol
May 1997
Purpose: To present the results of our treatment of dural cavernous sinus fistulas with surgical exposure of the superior ophthalmic vein (SOV), retrograde venous catheterization, and coil embolization of the cavernous sinus.
Methods: Twelve patients with dural cavernous sinus fistulas were treated via a retrograde transvenous SOV approach in our hospital during a 3-year period. All patients had been referred by ophthalmologists because of secondary glaucoma and decreased visual acuity.
J Stroke Cerebrovasc Dis
December 2009
Purpose: To evaluate pituitary gland size in cases of dural arteriovenous (AV) fistula in the cavernous sinus and to correlate the size with the degree of AV fistula.
Materials And Methods: Magnetic resonance images in 21 patients with angiographically proved dural AV fistula of the cavernous sinus were retrospectively reviewed. In four patients, findings obtained before and after embolization therapy were compared.
Purpose: To evaluate carotid artery volume-flow measurements with time-domain-processing ultrasonography (US).
Materials And Methods: Volume-flow measurements were obtained in the carotid arteries of nine swine with time-domain-processing US. Four swine were prepared with a model of an arteriovenous shunt.
From December 1990 to July 1995, the investigators participated in a prospective clinical study to evaluate the safety of the Guglielmi detachable coil (GDC) system for the treatment of aneurysms. This report summarizes the perioperative results from eight initial interventional neuroradiology centers in the United States. The report focuses on 403 patients who presented with acute subarachnoid hemorrhage from a ruptured intracranial aneurysm.
View Article and Find Full Text PDFObjective: Internal carotid artery aneurysms arising from the superior hypophyseal artery are frequently termed paraophthalmic or paraclinoid aneurysms, but they constitute a distinct anatomic entity. They are particularly amenable to endovascular treatment.
Methods: Between 1991 and 1995, we attempted treatment in 11 patients with superior hypophyseal artery aneurysms with Guglielmi detachable coil embolization and were successful in 10.
The technical feasibility of selective intranidal endovascular occlusion of experimental arteriovenous malformations with detachable superfine platinum electrodes was assessed in a swine model. The delivery and release of electrodes were performed within normal carotid retia mirabilia, the faster-flowing nidus (bilateral retia) of a carotid-jugular fistula-type model of an arteriovenous malformation, and a small-caliber H-type direct arteriovenous fistula. Controllable atraumatic placement of the electrodes was possible deep within each rete and in the middle of the fistula.
View Article and Find Full Text PDFAJNR Am J Neuroradiol
September 1996
Purpose: To study the effects of single-dose radiation on the porcine rete mirabile, a tangle of microvessels that mimics human arteriovenous malformations of the brain.
Methods: Eight retia mirabilia received a single dose of radiation under stereotactic location with digital angiography and CT. The following doses were applied: 20, 30, 40, 50, 60, 70, 80, and 90 Gy.
Background And Purpose: A Doppler guidewire was used to monitor progressive changes in draining vein flow parameters during experimental embolotherapy in a swine arteriovenous malformation (AVM) model.
Methods: A microcatheter was positioned superselectively in the main arterial feeder and main draining vein in each of 10 AVM models in swine. With use of the Doppler guidewire, preembolization arterial and venous average peak velocities (APVs) and pulsatility indices were recorded.
Objective: To describe indications and surgical techniques for embolization of cavernous sinus-dural fistulas (CDF) by passing platinum coils through a cannulated superior ophthalmic vein based on our clinical experience.
Design: Retrospective clinical review.
Setting: University tertiary referral hospital and eye institute.
Hemodynamics play a significant role in the propensity of intracranial arteriovenous malformations (AVMs) to hemorrhage and in influencing both therapeutic strategies and their complications. AVM hemodynamics are difficult to quantitate, particularly within or in close proximity to the nidus. Biomathematical models represent a theoretical method of investigating AVM hemodynamics but currently provide limited information because of the simplicity of simulated anatomic and physiological characteristics in available models.
View Article and Find Full Text PDFAJNR Am J Neuroradiol
March 1996
The results of surgery on multiple intracranial aneurysms tha involve the vertebrobasilar circulation are poor, and associated patient mortality remains high. We describe the endovascular treatment of four patients with mutiple aneurysms that involved the posterior intracrancial circulation. Satisfactory occlusion of all aneurysms was achieved by using electrolytically detachable coils, and all patients had a good clinical recovery.
View Article and Find Full Text PDFAJNR Am J Neuroradiol
February 1996
We assessed the suitability of a swine experimental arteriovenous malformation model for laboratory simulations and training in endovascular embolotherapy. Embolizations with liquid glue or particles were performed in 10 animals. The parameters of injection (microcatheter position, concentration and volume of embolic agent, injection rate) were deliberately varied to simulate results that may be observed in clinical practice.
View Article and Find Full Text PDFResults in nine patients with large or giant fusiform intracranial aneurysms that were treated with Guglielmi detachable coils (GDCs) are reported. There were six males and three females between the ages of 12 and 63. Four patients presented with subarachnoid hemorrhage (SAH) and four with mass effect; in one patient the aneurysm was asymptomatic and located in an arterial feeder of an arteriovenous malformation.
View Article and Find Full Text PDFWe report a patient with rupture of a giant distal vertebral artery aneurysm after balloon occlusion of the parent vertebral artery. We were able to occlude the residual lumen by endosaccular embolization and trapping with Guglielmi detachable coils via the anterior circulation. We suspect that either alterations in flow patterns or partial thrombosis of the aneurysm may have contributed to at least two subarachnoid hemorrhages within 2 days after the initial embolization.
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