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Colin P Derdeyn

Publications and source records attributed to Colin P Derdeyn.

At least 19 recordsLinked to original sources
PubMed2007

Carotid angioplasty and stent placement for restenosis after endarterectomy.

INTRODUCTION: Recurrent carotid stenosis following endarterectomy is a common complication, and reoperation may be associated with increased morbidity. The goal of this study was to determine the procedural safety and long-term complication rates of carotid angioplasty and stenting for recurrent stenosis. METHODS: Of 248 consecutive carotid angioplasty and/or stenting procedures performed at our institution between March 1996 and November 2005, 83 procedures for recurrent stenosis following endarterectomy were performed in 75 patients (mean age 68 years; 43 men, 32 women) without cerebral protection devices. The patients' medical records were retrospectively reviewed for vascular imaging reports and available clinical follow-up. Procedural and long-term complication rates were calculated. RESULTS: Recurrent stenosis was reduced from a mean of 80.6% to no significant stenosis in 82 of 83 procedures. The procedural stroke rate was 3 out of 83 procedures (3.6%). The procedural transient ischemic attack (TIA) rate was 2 out of 83 procedures (2.4%). Mean follow-up was 22.4 months (range 0.1 to 86.7 months) with at least 6 months follow-up for 54 of 83 procedures (65%). There were five TIAs and no strokes on follow-up (new TIAs at 25.5 and 43.4 months; recurrent TIAs at 1, 11.1, and 12 months, all with normal angiograms). The composite 30-day stroke, myocardial infarction, or death rate was 5 of 83 procedures (6.0%). CONCLUSION: In this series, angioplasty and stenting were effective in relieving stenosis secondary to recurrent carotid disease after endarterectomy, and have low rates of ischemic complications.

Aged↗
PubMed2007

Neuroendovascular magnetic navigation: clinical experience in ten patients.

INTRODUCTION: The magnetic navigation system consists of an externally generated magnetic field that is used to control and steer a magnetically tipped microguidewire. The goal of this study was to demonstrate that the use of the magnetic navigation system and its magnetic microguidewire is feasible and safe in all types of neuroendovascular procedures. METHODS: A magnetic navigation system is an interventional workstation that combines a biplanar fluoroscopy system with a computer-controlled magnetic field generator to provide both visualization and control of a magnetically activated endovascular microguidewire. Ten consecutive patients underwent a variety of neuroendovascular procedures using the magnetic guidance system and magnetic microguidewire. All patients presented with a neurovascular disease that was suitable for endovascular treatment. Multiple different devices and embolic agents were used. RESULTS: Of the ten patients, three were male and seven female. Their mean age was 53.9 years. The predominant neurovascular condition was the presence of intracranial aneurysm (nine patients). One patient had a left mandibular arteriovenous malformation. All treatments were successfully performed on the magnetic navigation system suite. The magnetic navigation system and the magnetic microguidewire allowed safe and accurate endovascular navigation allowing placement of the microcatheters in the desired location. There were no neurological complications or death in our series. CONCLUSION: The use of the magnetic navigation system and the magnetic microguidewire in the endovascular treatment of patients with neurovascular diseases is feasible and safe.

Adult↗
PubMed2006

Endovascular treatment of the vertebral artery origin in patients with symptoms of vertebrobasilar ischemia.

INTRODUCTION: We report our experience with the endovascular treatment of the vertebral artery origin in patients presenting with symptomatic vertebrobasilar ischemia and compare our results with those reported in the literature. METHODS: In 25 patients, 28 procedures were performed. Patients presented with posterior circulation ischemic symptoms despite optimal medical therapy with antiplatelet drugs and had a digital subtraction angiogram demonstrating stenosis of the origin of the vertebral artery greater than 50%. Retrospective review of the medical records, clinical notes and radiologic-procedural reports was performed. RESULTS: Of the 25 patients, 18 were male and 7 female. Their ages ranged from 50 to 84 years. In 23 of the 25 patients the contralateral vertebral artery was occluded, hypoplastic, absent, or had greater than 50% stenosis. In 13 of the 25 patients angiographic evidence of significant anterior circulation disease was demonstrated. In 18 of the 25 patients the left vertebral artery was affected. The mean stenosis was 82.6%. Follow-up records were available in 19 patients. The mean follow-up was 24 months. Five of the 19 patients had recurrent symptoms of vertebrobasilar ischemia and three patients were retreated. Of the 28 procedures performed, 23 were angioplasty/stenting and 5 were angioplasties alone. Overall technical success was achieved in 26 of the 28 procedures (92.8%). No procedure-related transient ischemic attack, stroke or death was noted. CONCLUSION: Endovascular treatment of the vertebral artery origin in this patient population is feasible, safe, and effective. There are some questions regarding the long-term follow-up and rate of restenosis and clinical recurrences that are yet to be answered.

Aged↗
PubMed2006

Safety and technical efficacy of over-the-wire balloons for the treatment of subarachnoid hemorrhage-induced cerebral vasospasm.

OBJECT: Over the past decade, low-pressure, flow-directed balloons have been replaced by over-the-wire balloons in the treatment of vasospasm induced by subarachnoid hemorrhage (SAH). The authors assess the procedural safety and technical efficacy of these newer devices. METHODS: Seventy-five patients who underwent 85 balloon angioplasty procedures for the treatment of SAH-induced vasospasm were identified from a prospective quality-assurance database. Medical records and angiographic reports were reviewed for evidence of procedural complications and technical efficacy. No vessel rupture or perforation occurred, but thromboembolic complications were noted in four (4.7%) of the 85 procedures. Balloon angioplasty was frequently attempted and successfully accomplished in the distal internal carotid (100%), proximal middle cerebral (94%), vertebral (73%), and basilar (88%) arteries. Severe narrowing was present in 89 proximal anterior cerebral arteries. Angioplasty was attempted in 41 of these vessels and was successful in only 14 (34%). In 19 of the 27 unsuccessful attempts, the balloon could not be advanced over the wire due to severe vasospasm or unfavorable vessel angle. Follow-up angiography in a subset of patients demonstrated that severe recurrent vasospasm occurred in 15 (13%) of 116 vessels studied after angioplasty. CONCLUSIONS: Over-the-wire balloons involve a low risk for vessel rupture. The anterior cerebral artery remains difficult to access and successfully treat with current devices. Further improvements in balloon design, such as smaller inflated diameters and better tracking, are necessary. Finally, thromboembolic complications remain an important concern, and severe vasospasm may recur after balloon angioplasty.

Adolescent↗
PubMed2006

Effect of intraarterial verapamil on the diameter of vasospastic intracranial arteries in patients with cerebral vasospasm.

OBJECT: This study was conducted to determine whether there is a change in intracranial arterial diameters after verapamil infusion for vasospasm and, if it is present, to determine whether the change occurs in proximal, intermediate, or distal vessels. METHODS: The authors measured arterial diameters in all patients treated with intraarterial verapamil at their institutions between August 2003 and September 2004. In all, 18 treatments were examined in 15 patients. Measurements were made before and after verapamil infusion in a blinded fashion with the aid of a magnification loupe at nine predetermined arterial sites on each angiogram. Baseline arterial measurements were made on each patient's initial angiogram and on the angiogram demonstrating spasm prior to endovascular therapy as well in 14 of the patients. Charts were retrospectively reviewed to determine whether the patients benefited from intraarterial verapamil. From the time of the initial angiogram to the time of vasospasm, there was a 21.6% decrease (p = 0.092) in proximal artery diameter, a 47.1% decrease (p < 0.05) in intermediate artery diameter, and a 12.4% decrease (p < 0.05) in distal artery diameter. There were no significant changes in the diameters of proximal, intermediate, or distal vessels after verapamil infusion (mean dose 7.4 mg, range 2.5-10 mg). After infusion of intraarterial verapamil, the proximal vessels showed a 1.1% decrease in diameter, the intermediate vessels showed a 9.4% increase, and the distal vessels showed a 3.3% decrease. CONCLUSIONS: Administration of intraarterial verapamil does not cause a significant increase in the diameter of vasospastic vessels at the administered doses.

Cerebral Angiography↗
PubMed2006

Effect of intraarterial papaverine and/or angioplasty on the cerebral veins in patients with vasospasm after subarachnoid hemorrhage due to ruptured intracranial aneurysms.

OBJECT: The goal in this study was to determine if there was a change in intracranial venous diameters after endovascular treatment of carotid distribution vasospasm caused by subarachnoid hemorrhage. METHODS: The venous diameters were measured in all patients who received intraarterial papaverine and/or balloon angioplasty for treatment of vasospasm during the study period of 3 years. To evaluate the veins of Labbe and Trolard, the straight sinus, and the superior sagittal sinus (SSS), measurements were performed in a blinded manner with the aid of a magnification loupe. Predetermined sites were evaluated on angiograms obtained before and after endovascular treatment. Forty-three treatments in 26 patients were included: 18 patients (33 territories) were treated with intraarterial papaverine alone, four (four territories) were treated with balloon angioplasty alone, and four (six territories) were treated with both papaverine infusion and angioplasty. The mean measured venous diameters increased significantly after addition of papaverine (10.9%), and also after combined papaverine and angioplasty (4.2%). There was no statistically significant increase in the mean venous diameters after angioplasty alone. If the initial intracranial pressure (ICP) was less than 15 mm Hg before treatment, the veins showed a greater tendency to dilate than if the initial ICP measurements were greater than 15 mm Hg. The straight sinus and the SSS increased more in diameter than the veins of Labbe and Trolard. There was no statistically significant correlation between the change in venous diameters with treatment and ICP. CONCLUSIONS: Endovascular treatment produces measurable increases in intracranial venous diameters. However, these changes do not correlate with changes in ICP.

Adult↗
PubMed2006

Clinical features and outcome in North American adults with moyamoya phenomenon.

BACKGROUND AND PURPOSE: To describe baseline clinical features and outcomes of adults with moyamoya phenomenon treated at a single North American institution. METHODS: We identified 34 adults with moyamoya phenomenon by review of angiographic records. Clinical presentation and baseline stroke risk factors were obtained by chart review. Follow-up was obtained prospectively. A 5-year Kaplan-Meier stroke risk was calculated. RESULTS: The median age was 42 (range 20 to 79) years. Twenty-five were women. The initial symptom was ischemia, hemorrhage, or asymptomatic in 24, 7, and 3 patients, respectively. Twenty-two had bilateral involvement and 12 had unilateral moyamoya vessels. Baseline stroke risk factors were similar between groups. The median follow-up in 31 living patients was 5.1 (range 0.2 to 19.6) years. Fourteen patients were treated with surgical revascularization (20 total hemispheres). In medically treated symptomatic hemispheres, the 5-year risk of recurrent ipsilateral stroke was 65% after the initial symptom and 27% after angiographic diagnosis. Patients with bilateral involvement presenting with ischemic symptoms were at the highest risk of subsequent stroke (n=17, 5-year risk of stroke with medical treatment after first symptom of 82%). In surgically treated hemispheres, the 5-year risk of perioperative or subsequent ipsilateral stroke or death was 17%. This was significantly different compared with medical treatment after first symptom (P=0.02) but not after angiographic diagnosis. CONCLUSIONS: Moyamoya phenomenon in North American adults is associated with a high risk of recurrent stroke, particularly those with bilateral involvement and ischemic symptoms. These data suggest a potential benefit with surgery if diagnosis could be made earlier.

Adult↗
PubMed2006

Goldvalve detachable balloon: "in vitro" assessment of safety and imaging artifacts in a 3-T MR system.

The Goldvalve balloon is the only currently available detachable balloon. We undertook a study to determine safety and imaging artifacts in a MR environment. We found no evidence for heating or deflection of the balloon in a comprehensive series of in vitro experiments at 3 T. MR imaging at field strengths up to 3 T of patients with implanted Goldvalve balloons is safe. Imaging artifacts are minimal.

Artifacts↗
PubMed2006

Etiology of strokes in children with sickle cell anemia.

The most devastating complication of sickle cell anemia is cerebral infarction, affecting approximately 30% of all individuals with sickle cell anemia. Despite being one of the most common causes of stroke in infants and children, the mechanism of cerebral infarction in this population has not been extensively studied and is poorly understood. Multiple, synergistic factors are important in the pathogenesis of stroke including the hemodynamic effects of cerebral arterial occlusive disease, viscosity, chronic and acute anemia and acute medical events. This review focuses on the relationship between these factors in order to provide a foundation for further study of the etiology of strokes in this high-risk population.

Anemia, Sickle Cell↗
PubMed2006

Current status of manpower needs for management of cerebrovascular disease.

The cerebrovascular discipline has undergone dramatic changes in recent years. The advent, development, and now widespread application of endovascular therapy for various cerebrovascular diseases has been the predominant influence behind many of these changes, but other factors (some scientific, others less so) have also contributed significantly. As our discipline evolves, it is critical to periodically examine how such changes have altered our manner of practice and to determine what impact such changes might have on manpower allocation and training for the future. This article is our attempt at providing such an assessment. First, we will critically review recent trends within the fields of intracranial aneurysms, arteriovenous malformations, carotid atherosclerotic occlusive disease, and ischemic stroke and how these trends have impacted our profession. Thereafter, we will provide a perspective on what the cerebrovascular manpower needs of the future might be and by whom these needs will be met. Finally, we will examine how the new generation of cerebrovascular specialists, including neurosurgeons, neuroradiologists, and some neurologists, will attain their requisite surgical or endovascular training and attempt to determine which careers, pathways, and opportunities will be available to these individuals in the future.

Career Mobility↗
PubMed2006

Fibrinolytic treatment for acute ischaemic stroke.

Ischaemic stroke is a leading cause of death and disability in the US. At present, intravenous administration of tissue plasminogen activator within 3 h of symptom onset is the only proven effective treatment for patients with acute ischaemic stroke. Unfortunately, most treated patients do not make a functional recovery and very few patients presenting with acute stroke qualify for intravenous tissue plasminogen activator therapy. The focus of current research is to extend the therapeutic window for intervention beyond 3 h, and to improve the outcome of treated patients. The purpose of the present paper is to describe the current state of affairs for intravenous plasminogen activators, and to review recently published research. Agents and strategies under investigation include the intra-arterial delivery of plasminogen activators or antiplatelet agents, as well as combined intravenous/intra-arterial protocols.

Animals↗
PubMed2006

Percutaneous transvenous embolization of a dural arteriovenous fistula through a mastoid emissary vein. Technical note.

Definitive endovascular treatment of dural arteriovenous fistulas (DAVFs) requires obliteration of the site of the fistula: either the diseased dural sinus or the pial vein. Access to this site is often limited by occlusion of the sinus proximal and distal to the segment containing the fistula. The authors describe a technique in which the mastoid emissary vein is used to gain access to a Borden-Shucart Type II DAVF in the transverse-sigmoid sinus. Recognition of this route of access, if present, may facilitate endovascular treatment of these lesions. Access to the transverse sinus via this approach can be straightforward and may be underused.

Catheterization, Peripheral↗
PubMed2005

Training, competency, and credentialing standards for diagnostic cervicocerebral angiography, carotid stenting, and cerebrovascular intervention: a joint statement from the American Academy of Neurology, the American Association of Neurological Surgeons, the American Society of Interventional and Therapeutic Neuroradiology, the American Society of Neuroradiology, the Congress of Neurological Surgeons, the AANS/CNS Cerebrovascular Section, and the Society of Interventional Radiology.

Explore the source record for details and available documents.

Angioplasty↗
PubMed2005

Procedure complications of carotid angioplasty and stent placement without cerebral protection devices.

OBJECT: The goal in this retrospective study was to examine the procedural complication rate for carotid angioplasty and stent placement performed without cerebral protection devices. METHODS: Between March 1996 and December 2003, 167 carotid angioplasty and/or stent placement procedures were performed without cerebral protection devices in 152 patients (57 women and 95 men whose mean age was 64 years, range 19-92 years). Seven of these patients underwent angioplasty alone. Eighty-nine patients presented with focal neurological symptoms. Indications for surgery included atherosclerosis, radiation-associated stenosis, dissection, pseudoaneurysm, and stretched endovascular coils from aneurysm treatment. In this study, the patients' medical records were reviewed for clinical characteristics, techniques used, and resulting intraprocedural and 30-day complication rates. The intraprocedural stroke rate was four (2.4%) of 167; this included three hemispheric strokes and one retinal embolus. All events occurred in patients who had symptomatic stenosis. The procedural transient ischemic complication rate was six (3.6%) of 167, as was the procedural nonneurological complication rate. During the 30 days postprocedure, one patient had died and three had suffered permanent ischemic events (two cerebral and one ocular). The composite 30-day postprocedural stroke and death rate was eight (5%) of 160. The rate of asymptomatic angiographically confirmed abnormalities was 0.6% (one treated vessel that was occluded but asymptomatic). The 30-day rate of nonneurological complications was 2.5%. A strong association between intraprocedural thromboembolic events (eight cases) and prior ischemic symptoms was found (p = 0.01). CONCLUSIONS: Carotid angioplasty and stent placement without cerebral protection devices is safe, particularly in patients without symptomatic stenosis.

Adult↗
PubMed2005

Positron emission tomography imaging of cerebral ischemia.

Positron emission tomography (PET) uniquely allows the in vivo regional measurement of several important physiologic parameters in living humans, including cerebral blood flow and oxygen metabolism. PET studies have advanced our understanding of normal human brain physiology and, as detailed in this article, our understanding of human cerebrovascular pathophysiology. This article focuses on knowledge gained from PET regarding acute ischemic stroke and chronic oligemia from arterial occlusive disease. Knowledge of the responses of the brain and its vasculature to ischemia and oligemia is growing more important with the increasing availability of CT and MR perfusion techniques.

Arterial Occlusive Diseases↗
PubMed2005

Indications for cerebral revascularization for patients with atherosclerotic carotid occlusion.

Patients with complete carotid occlusion and recent ischemic symptoms are at high risk for subsequent stroke, particularly those with evidence of severe hemodynamic impairment due to poor collateral flow. Treatment options for these patients include direct extracranial to intracranial arterial bypass, or interventions aimed at improving collateral sources of flow such as endarterectomy or angioplasty and stenting of the ipsilateral external carotid artery, the contralateral carotid artery, or the vertebral arteries. The evidence supporting the use of these procedures for patients with complete occlusion of the carotid artery will be the focus of this article. The use of physiologic imaging to select subgroups of patients at high risk due to hemodynamic factors will also be discussed.

Journal Article↗
PubMed2005

Outcomes of carotid angioplasty and stenting for radiation-associated stenosis.

BACKGROUND AND PURPOSE: In light of their high surgical risk, carotid angioplasty and stent placement may be preferred in patients with radiation-associated carotid stenosis. The purpose of this study was to determine the procedural complication rate, patency, and clinical outcomes after carotid angioplasty and stent placement in this small group of high-risk patients. METHODS: Sixteen patients (mean age, 65 years; 5 women and 11 men) who received radiation therapy for head and/or neck malignancy subsequently developed carotid stenosis (mean, 84%; range, 70%-99%) in a total of 19 carotid arteries, which were treated with angioplasty and stent placement. The patients were followed for a mean time of 28 months (range, 5-78 months) with periodic Doppler studies, angiography, CT angiography, or clinically. RESULTS: In the total 19 stented carotid arteries, 23 procedures were performed (22 stent placement procedures and one repeat angioplasty). The procedural stroke rate was 1/23 (4%). The procedural transient ischemic attack rate was 0/23 (0%). There was one other observed complication: a puncture site hematoma. The 30-day postprocedure complication rate was 0/23 (0%); no neurologic symptoms were reported. Fifteen of the 19 vessels (79%) developed no new stenosis throughout the follow-up period. Two of 19 (11%) vessels had repeat angioplasty and stent placement; 1/19 (5%) had a repeat angioplasty. One restented vessel has remained patent for 50 months. Another restented vessel required a third stent placement 17 months after the second. Two of 19 (11%) vessels occluded per Doppler examination 14 and 22 months postprocedure. CONCLUSION: Angioplasty and stent placement have low rates of complications and restenosis in the treatment of radiation-associated carotid occlusive disease.

Aged↗