Showing papers by "L. Nelson Hopkins published in 2003"
TL;DR: It is suggested that apoptosis represents a prominent form of cell death associated with ICH in the perihematoma region, and further studies are required to define the mediators of apoptosis in ICH.
Abstract: OBJECTIVEThe goals of this study were to identify and quantify the presence of programmed cell death (apoptosis) in intracerebral hemorrhage (ICH) among human subjects. Recent evidence from laboratory models suggests that cell death in the perihematoma region may involve apoptosis.METHODSRetrospecti
183 citations
TL;DR: The present study suggests that glutamate and other amino acids accumulate transiently in extracellular fluids in the perihematoma region during the early period of intracerebral hemorrhage.
Abstract: ObjectiveTo determine whether extracellular concentrations of glutamate and other amino acids are significantly elevated after intracerebral hemorrhage and, if so, the temporal characteristics of these changes. Although the role of excitotoxic amino acids, particularly that of glutamate, has been de
160 citations
TL;DR: A single-institution series of tentorial DAVMs treated during a 12-year period is presented, addressing the current controversies, and the rationale for the current therapeutic strategy is presented.
Abstract: OBJECTIVE Tentorial dural arteriovenous malformations (DAVMs) are uncommon lesions associated with an aggressive natural history. Controversy exists regarding their optimal treatment. We present a single-institution series of tentorial DAVMs treated during a 12-year period, address the current controversies, and present the rationale for our current therapeutic strategy. METHODS Twenty-two patients with tentorial DAVMs were treated between 1988 and 2000. Treatment consisted of transarterial or transvenous embolization, surgical resection, disconnection of venous drainage, or a combination of these therapies. The clinical presentations, radiological features, treatment strategies, and results were studied. RESULTS Eighteen patients (82%) presented with intracranial hemorrhage or progressive neurological deficits. Retrograde leptomeningeal venous drainage was documented in 22 cases (100%), classifying the lesions as Borden Type III. Angiographic follow-up monitoring was performed for 0 to 120 months and clinical follow-up monitoring for 1 to 120 months. Posttreatment angiography demonstrated obliteration in 22 cases (100%). Two patients experienced neurological decline after endovascular treatment and died. All of the 20 surviving patients exhibited clinical improvement; there were no episodes of rehemorrhage or new neurological deficits. Outcomes were excellent in 17 cases (77%), good in 2 cases (9%), and fair in 1 case (5%), and there were 2 deaths (9%). CONCLUSION Tentorial DAVMs are aggressive lesions that require prompt total angiographic obliteration. Disconnection of the venous drainage from the fistula may be accomplished with transarterial embolization to the venous side, transvenous embolization, or surgical disconnection of the fistula. We think that extensive nidal resections carry more risk and are unnecessary. We do not think there is a role for stereotactic radiosurgery in the treatment of these lesions.
142 citations
TL;DR: It is suggested that direct stent placement in the BA should be avoided to minimize the risk of periprocedure morbidity and displacement of debris by the stent into the ostia of small brainstem perforating vessels may be responsible for the complications noted.
Abstract: Object. Medically refractory, symptomatic atherosclerotic disease of the basilar artery (BA) portends a poor prognosis. Studies have shown morbidity rates following placement of stents in these lesions to be quite variable, ranging from 0 to 30%. The authors review their experience with BA stent placement for severe atherosclerotic disease to determine whether an increase in neurological morbidity is associated with direct stent placement (that performed without predilation angioplasty) compared with conventional stent placement (that performed immediately after predilation angioplasty) or staged stent placement (angioplasty followed ≥ 1 month later by stent placement with or without repeated angioplasty). Methods. The authors retrospectively reviewed the medical records from a consecutive series of 10 patients who underwent stent placement for medically refractory, symptomatic atherosclerotic disease of the BA between February 1999 and November 2002. Patient records were analyzed for symptoms at presenta...
85 citations
TL;DR: SC can produce better results than CE in patients with UIA of the anterior circulation and CE as a first-line treatment should be reserved for patients with UIAs with a fundus-to-neck ratio of 2.5 or greater.
Abstract: OBJECTIVE: Recent reports in the literature have described a significant discrepancy in adverse outcomes between coil embolization (CE; 10%) and surgical clipping (SC; 25%) for the management of unruptured intracranial aneurysms (UIA). This discrepancy led us to analyze our experience. METHODS: In 1996, we designed a prospective study of patients with UIA in which CE was considered the treatment of choice and was performed if the interventional neuroradiologists deemed the aneurysm's fundus-to-neck ratio accessible for CE. SC was performed only if complete CE was unlikely to be achieved or in patients in whom CE already had failed. RESULTS: CE was performed in 38 patients with at least one UIA (41 UIAs, 83% in the anterior circulation). SC was performed in 39 patients with at least one UIA unsuitable for CE (59 UIAs, including 6 after failed CE, 96.5% in the anterior circulation). For CE, the total obliteration rate was 56.1%, the subtotal was 14.6%, and CE failed in 29.3%. There were transient complications in 10% of the cases and permanent complications in 7.5%. Of the 12 failed CE procedures, 7 (58%) were performed for middle cerebral artery aneurysms. For SC, the total obliteration rate was 93.2%, the subtotal was 1.7%, and SC failed (wrapping) in 5.1%. There were transient complications in 16.3% of the patients and permanent complications in 1.7%. The success rate for CE was similar to that for SC only when CE was used for aneurysms with a fundus-to-neck ratio of at least 2.5. CONCLUSION: SC can produce better results than CE in patients with UIA of the anterior circulation. CE as a first-line treatment should be reserved for patients with UIAs with a fundus-to-neck ratio of 2.5 or greater.
78 citations
TL;DR: The flexible, low-profile stents used in this study had no angiographically or clinically apparent effect on the major intracranial branches across which they were placed.
Abstract: OBJECTIVE: One concern with respect to stent procedures performed to treat patients with intracrantal lesions is the fate of normal major arterial branches after sents are placed across them. Because most of of these lesions occur at vessel vti;i;i t =I bifurcations or at branch points, a normal major branch often arises near the lesion and may be difficult to avoid during stent positioning. The aim of this article is to describe the angiographic outcome of intracranial major branch arteries crossed by a stent in the intracranial circulation. METHODS: We examined the immediate postprocedural cerebral angiograms of the 40 patients who underwent intracrantal stenting at the University at Bufalo, Buffalo, NY, between June 1998 and April 2000. to each of 10 patients. the stent was placed across a nurmal major branch artery. Stents were used to treat aneurysms in seven patients and intracranial stenosis in three patients. The latest cerebral angiogram available was reviewed, and the patency of the major branch arteries was evaluated. RESULTS: The angiographic follow-up period ranged from 4 days to 35 months (mean follow-up, 10 mo), Each of the 10 major branch arteries was patent. No infarcis were associated with the territory of the major branch arteries crossed by the stents, and no patient experienced a related episode of clinical ischemia. Four patients died as a result of causes unrelated to the stenting procedure. The histology of a middle cerebral artery stent that was placed across a lenticuiostriate perforator is presented. CONCLUSION: The flexible, low-profile stents used in this study had no angiographically or clinically apparent effect on the major Intracranial branches across which they were placed.
77 citations
TL;DR: The transradial approach is becoming an increasingly viable alternative route for stent placement in patients with contraindicated or complicated femoral access routes as devices become increasingly more pliable and smaller.
Abstract: OBJECTIVE AND IMPORTANCE: We describe a case of endoluminal stent placement for a cervical internal carotid artery stenosis in which percutaneous access was obtained via the radial artery. CLINICAL PRESENTATION: A 69-year-old man with known disease of the carotid, peripheral, and coronary arteries as well as chronic obstructive pulmonary disease presented for endoluminal revascularization of a severe, progressive right internal carotid artery stenosis. TECHNIQUE: Transfemoral access was complicated by the previous placement of a synthetic graft as the result of a previous right-to-left iliofemoral artery bypass procedure and an aortoiliac occlusion. A transradial approach was successfully attempted, and a Precise stent (Cordis Endovascular, Mimi Lakes, FL) was successfully placed through a 6-French gaide sheath. CONCLUSION: The transradial approach is becoming an increasingly viable alternative route for stent placement in patients with contraindicated or complicated femoral access routes. As devices become increasingly more pliable and smaller, the transradial route will be used with increasing frequency in this select patient population for stenting of both the cervical and intracranial circulation.
55 citations
Journal Article•
TL;DR: In this article, the authors evaluated the association of educational attainment with the incidence of fatal stroke, ischemic stroke, intracerebral hemorrhage, and myocardial infarction in a cohort of 21,443 United States adults.
Abstract: BACKGROUND Prior reports have suggested that low educational attainment could be associated with higher incidence of some of the cardiovascular conditions MATERIAL/METHODS We evaluated the association of educational attainment (> or =12 years or <12 years) with the incidence of fatal strokes, ischemic stroke, intracerebral hemorrhage, and myocardial infarction in a cohort of 21,443 United States adults who participated in either the First National Health and Nutrition Examination Survey (NHANES-I) Epidemiologic Follow-up Study (NHEFS) or the Second National Health and Nutrition Examination Survey Mortality Follow-up Study (NHANES-II) Cox proportional hazards analyses were used to examine the relationships RESULTS During a mean follow-up period of 152+/-46 years, the risk for all fatal strokes was increased in persons who reported less than 12 years of education The increased risk was more prominent in persons aged 50 years or less (relative risk [RR], 26; 95% confidence interval [CI], 11-60) compared with persons aged greater than 50 years (RR, 13, 95% CI, 10-16) A higher risk of myocardial infarction associated with less than 12 years of education was observed in both persons aged 50 years or less (RR 17, 95% CI 12-24) and those aged greater than 50 years (RR 13, 95% CI 11-15) The risk for fatal intracerebral hemorrhages (RR 20, 95% CI 11-35) was higher in persons with less than 12 years of education (no significant interaction demonstrated with age) CONCLUSIONS Educational attainment has a significant effect on the risk for stroke and myocardial infarction, independent of socioeconomic status and other cardiovascular risk factors
55 citations
TL;DR: In this communication, technical preferences developed during the experience with intracranial aneurysm coiling are summarized.
Abstract: Since the introduction of Guglielmi detachable coils more than a decade ago, the coiling technique for the treatment of intracranial aneurysms has been enhanced with technical and technological refinements Both neurosurgeons and neuroradiologists have participated in this process Stents and nondetachable balloons have been useful in the coiling of some wide-necked aneurysms An increasing number of neurosurgeons are pursuing fellowship training in neuroendovascular techniques Moreover, most neurosurgeons work closely with neurointerventionists In this communication, technical preferences developed during our experience with intracranial aneurysm coiling are summarized
46 citations
TL;DR: Strategies for and impediments to gene therapy and stem cell therapy of the central nervous system are summarized and the concept of a potential new approach, namely endovascular restorative neurosurgery, is advanced.
Abstract: The amalgam of molecular biology and neurosurgery offers immense promise for neurorestoration and the management of neurodegenerative deficiencies, developmental disorders, neoplasms, stroke, and trauma. This article summarizes present strategies for and impediments to gene therapy and stem cell therapy of the central nervous system and advances the concept of a potential new approach, namely endovascular restorative neurosurgery. The objectives of gene transfer to the central nervous system are efficient transfection of host cells, selective sustained expression of the transgene, and lack of toxicity or immune excitation. The requisite elements of this process are the identification of candidate diseases, the construction of vehicles for gene transfer, regulated expression, and physical delivery. In the selection of target disorders, the underlying genetic events to be overcome, as well as their spatial and temporal distributions, must be considered. These factors determine the requirements for the physical dispersal of the transgene, the duration of transgene expression, and the quantity of transgene product needed to abrogate the disease phenotype. Vehicles for conveying the transgene to the central nervous system include viral vectors (retroviruses, lentiviruses, adenoviruses, adeno-associated viruses, and herpes simplex virus), liposomes, and genetically engineered cells, including neural stem cells. Delivery of the transgene into the brain presents several challenges, including limited and potentially risky access through the cranium, sensitivity to volumetric changes, restricted diffusion, and the blood-brain barrier. Genetic or cellular therapeutic agents may be injected directly into the brain parenchyma (via stereotaxy or craniotomy), into the cerebrospinal fluid (in the ventricles or cisterns), or into the bloodstream (intravenously or intra-arterially). The advantages of the endovascular route include the potential for widespread distribution, the ability to deliver large volumes, limited perturbation of neural tissue, and the feasibility of repeated administration.
40 citations
TL;DR: Patients with unruptured intracranial aneurysms often present with headaches and are diagnosed with headaches following surgery.
Abstract: Background.—Patients with unruptured intracranial aneurysms often present with headaches.
Objective.—To determine the effect of endovascular treatment on the character and frequency of headaches in patients with unruptured intracranial aneurysms.
Methods.—We reviewed the medical records of all patients who underwent endovascular treatment for unruptured intracranial aneurysms within a 9.5-year period. These patients were mailed a standard questionnaire in which they were asked about the frequency and character of any headache experienced before or after (or both) endovascular treatment. They were also asked to grade improvement or worsening of headaches after the procedure as mild (activities of daily living were not affected), moderate (activities of daily living were affected), or significant (the change resulted in an ability to perform new activities of daily living or an inability to perform previous activities of daily living).
Results.—Forty-seven patients with unruptured aneurysms who underwent Guglielmi detachable coil embolization responded to the questionnaire. Of these, 32 patients (mean age, 52.7 years [SD, 13.4]; 22 were women) had experienced headaches before the procedure. Nineteen patients (59%) reported improvement in severity of headaches after embolization. Improvement was graded as significant by 7 patients, moderate by 8, and mild by 4. Two patients (6%) reported worsening severity of headaches graded as moderate. Five of 15 patients without headaches before embolization reported onset of mild (n = 4) or severe (n = 1) headaches after treatment.
Conclusion.—Guglielmi detachable coil embolization of unruptured intracranial aneurysms was associated with reduction in severity of headaches in the majority of patients who had experienced preprocedural headaches.
TL;DR: This in vivo intracranial stent model was developed to assess proliferative and inflammatory responses to endoluminal stent implantation in the cerebrovasculature and indicates that a lower percentage of occlusion occurs 12 weeks after implantation of heparin-coated compared with uncoated stents.
Abstract: Object. No animal model currently exists for the examination of time-dependent histological changes occurring in intracranial vessels after endoluminal stent placement. The authors' goal was to develop a reproducible in vivo model of stent implantation in intracranial vessels in dogs that was capable of demonstrating stent-related vascular changes after the implantation of coated and uncoated devices. Methods. The authors implanted heparin-coated or uncoated stents in the basilar arteries (BAs) of 11 mongrel dogs. In a 12th animal, one coated stent was implanted in the BA and a second uncoated one was implanted in the distal anterior spinal artery. All the devices were oversized to induce intimal injury. Surviving animals were observed for 12 weeks, after which they underwent repeated angiography before planned death and removal of the brain. Histological studies and computer-assisted morphometric analyses were conducted on stent-treated and untreated sections of the BAs to assess the percentage of stenos...
Journal Article•
TL;DR: The experience demonstrates the feasibility and safety of the CB for the treatment of carotid in-stent stenosis in three patients, and due to the less traumatic nature of this balloon, its use may result in a lower occurrence of in-state stenosis as compared to a conventional angioplasty balloon.
Abstract: Carotid artery in-stent stenosis, a possible long-term complication of carotid angioplasty and stenting, is currently treated by inflation of a non-compliant angioplasty balloon. Better initial results and less recurrence of stenosis have been documented in the coronary literature with the use of the Cutting Balloon (CB, Boston Scientific Interventional Technologies, San Diego, California) for angioplasty, in comparison with traditional balloon angioplasty. We report our collective experience with the use of the CB to treat carotid in-stent stenosis in three patients. Excellent angiographic and clinical results were achieved. No complications occurred. The lesions in two patients were successfully treated with the CB alone; adjunctive stent placement was required in a third patient. Our experience demonstrates the feasibility and safety of the CB for the treatment of carotid in-stent stenosis in three patients. Due to the less traumatic nature of this balloon, its use may result in a lower occurrence of in-stent stenosis as compared to a conventional angioplasty balloon. To our knowledge, this is the first report of the use of the CB for carotid in-stent stenosis.
TL;DR: Placement of the NexStent was feasible and resulted in the effective treatment of patients with CA stenosis, with promising long-term results.
Abstract: Object Carotid angioplasty with stent placement has been proposed as an alternative method for revascularization of carotid artery (CA) stenosis A novel stent with a coiled sheet design (NexStent; EndoTex Interventional Systems, Inc, Cupertino, CA) has been introduced because it provides improved flexibility over conventional tubular designs during navigation through tortuous arterial segments The authors report the results of a multicenter study in which they evaluated the safety, feasibility, and effectiveness of this stent in the treatment of CA stenosis Methods Enrollment was limited to patients with 70% or more symptomatic or asymptomatic stenosis of the internal CA The primary end point was a technically successful implantation procedure (delivery of the stent to the target site and retrieval of the delivery device) resulting in less than 30% residual stenosis on angiograms obtained immediately postprocedure and no death or ipsilateral stroke immediately after or within 30 days following the
TL;DR: To the authors' knowledge, this is the first reported case in which a CCF developed after angioplasty was performed using a coronary balloon, and long-term angiographic and clinical evaluation is needed to test the suitability and durability of intracranial angiopLasty and stent placement in the treatment of symptomatic intrACranial stenosis.
Abstract: ✓ The authors report a case of an iatrogenic carotid—cavernous fistula (CCF) associated with intracranial angioplasty. Angioplasty was performed using a 3 × 10-mm Open Sail coronary balloon in a patient with high-grade stenosis of the left cavernous internal carotid artery (ICA). After angioplasty, a perforation developed in the cavernous ICA, resulting in a CCF. A 3.5 × 9—mm S670 coronary stent was used to treat the fistula. To the authors' knowledge, this is the first reported case in which a CCF developed after angioplasty was performed using a coronary balloon. Long-term angiographic and clinical evaluation is needed to test the suitability and durability of intracranial angioplasty and stent placement in the treatment of symptomatic intracranial stenosis.
TL;DR: Close collaboration among neurointerventionists, radiosurgeons, microvascular neurosurgeons, intensivists, and neurologists is needed to ensure balanced decision making in terms of AVM treatment in general and AVM embolization in particular.
TL;DR: Patients undergoing carotid stenting were randomized to receive either aspirin, clopidogrel, and heparin therapy, or adjunct therapy with an abciximab bolus and infusion for 12 hours.
Abstract: We read with great interest the article by Kopp et al in this issue of Stroke .1 In this article, patients undergoing carotid stenting were randomized to receive either aspirin, clopidogrel, and heparin therapy, or adjunct therapy with an abciximab bolus and infusion for 12 hours. A third cohort of 30 patients underwent stenting with filter protection using the same …
01 Jan 2003