L. Nelson Hopkins

Bio: L. Nelson Hopkins is an academic researcher from University at Buffalo. The author has contributed to research in topics: Stroke & Angioplasty. The author has an hindex of 68, co-authored 399 publications receiving 17634 citations. Previous affiliations of L. Nelson Hopkins include University at Albany, SUNY & Women & Children's Hospital of Buffalo.

Stenting versus Endarterectomy for Treatment of Carotid-Artery Stenosis

Abstract: For 2502 patients over a median follow-up period of 2.5 years, there was no significant difference in the estimated 4-year rates of the primary end point between the stenting group and the endarterectomy group (7.2% and 6.8%, respectively; hazard ratio with stenting, 1.11; 95% confidence interval, 0.81 to 1.51; P = 0.51). There was no differential treatment effect with regard to the primary end point according to symptomatic status (P = 0.84) or sex (P = 0.34). The 4-year rate of stroke or death was 6.4% with stenting and 4.7% with endarterectomy (hazard ratio, 1.50; P = 0.03); the rates among symptomatic patients were 8.0% and 6.4% (hazard ratio, 1.37; P = 0.14), and the rates among asymptomatic patients were 4.5% and 2.7% (hazard ratio, 1.86; P = 0.07), respectively. Periprocedural rates of individual components of the end points differed between the stenting group and the endarterectomy group: for death (0.7% vs. 0.3%, P = 0.18), for stroke (4.1% vs. 2.3%, P = 0.01), and for myocardial infarction (1.1% vs. 2.3%, P = 0.03). After this period, the incidences of ipsilateral stroke with stenting and with endarterectomy were similarly low (2.0% and 2.4%, respectively; P = 0.85). CONCLUSIONS Among patients with symptomatic or asymptomatic carotid stenosis, the risk of the composite primary outcome of stroke, myocardial infarction, or death did not differ significantly in the group undergoing carotid-artery stenting and the group undergoing carotid endarterectomy. During the periprocedural period, there was a higher risk of stroke with stenting and a higher risk of myocardial infarction with endarterectomy. (ClinicalTrials.gov number, NCT00004732.)

Hemodynamic-morphologic discriminants for intracranial aneurysm rupture.

Abstract: Background and purpose the purpose of this study was to identify significant morphological and hemodynamic parameters that discriminate intracranial aneurysm rupture status using 3-dimensional angiography and computational fluid dynamics. Methods one hundred nineteen intracranial aneurysms (38 ruptured, 81 unruptured) were analyzed from 3-dimensional angiographic images and computational fluid dynamics. Six morphological and 7 hemodynamic parameters were evaluated for significance with respect to rupture. Receiver operating characteristic analysis identified area under the curve (AUC) and optimal thresholds separating ruptured from unruptured aneurysms for each parameter. Significant parameters were examined by multivariate logistic regression analysis in 3 predictive models-morphology only, hemodynamics only, and combined-to identify independent discriminants, and the AUC receiver operating characteristic of the predicted probability of rupture status was compared among these models. Results morphological parameters (size ratio, undulation index, ellipticity index, and nonsphericity index) and hemodynamic parameters (average wall shear stress [WSS], maximum intra-aneurysmal WSS, low WSS area, average oscillatory shear index, number of vortices, and relative resident time) achieved statistical significance (P Conclusions all 3 models-morphological (based on size ratio), hemodynamic (based on WSS and oscillatory shear index), and combined-discriminate intracranial aneurysm rupture status with high AUC values. Hemodynamics is as important as morphology in discriminating aneurysm rupture status.

Morphology Parameters for Intracranial Aneurysm Rupture Risk Assessment

Abstract: Intracranial aneurysms (IA) affect approximately 2 to 5% of the entire population (23, 25) Ruptured IAs typically cause subarachnoid hemorrhage (SAH) and its sequelae, resulting in significant morbidity and mortality Among patients who have SAH, 50 to 60% will die from the initial hemorrhage and a further 20 to 25% will experience complications (30) However, despite their expected common occurrence, only 1% of all IAs actually rupture (25) Although the morbidity and mortality associated with rupture may suggest that an incidentally detected aneurysm should be treated to forestall the catastrophic event of SAH, the two current methods of treatment (open microsurgical aneurysm clip ligation or endovascular aneurysm coil embolization) are not without some risk of major morbidity and mortality (8, 31) Therefore, an accurate metric (or several metrics) to judge the risk of rupture of an aneurysm is critical to aid in generating the best possible treatment algorithm Hemodynamics has been shown to play an important role in IA pathophysiology and rupture Using computational fluid dynamics, Hassan et al (11) suggested that high wall shear stress (WSS) may be responsible for IA growth and rupture in high-flow aneurysms, whereas the predominant factors causing rupture in low-flow aneurysms are high intra-aneurysmal pressure and flow stasis Cebral et al (6) demonstrated that ruptured IAs have unstable flow patterns, smaller impinging jet diameters, and smaller impingement zones Shojima et al (24) found that ruptured IAs have a higher average WSS in the aneurysm sac than unruptured IAs They observed recirculation zones and blood stasis at the apex of ruptured IAs It is important to realize that IA hemodynamics are strongly dependent on the geometry of the aneurysmal sac and its feeding vessel (11, 13, 26) For a given geometry, Cebral et al (5) showed that hemodynamics do not vary significantly with physiological variations of flow rate, blood pressure, and waveform Therefore, suitable parameters characterizing IA geometry can capture the characteristic hemodynamics and potentially predict rupture risk Several past studies have investigated such parameters The most ubiquitous parameter is IA size Although aneurysms exceeding 10 mm in size are considered to be dangerous, several studies have shown that a large percentage of ruptured aneurysms are, in fact, smaller than 10 mm (2, 9, 22, 23, 26, 27, 30) The relationship between IA rupture risk and IA size has yet to be completely elucidated Aneurysm shape has been studied as well, and certain shape parameters show stronger correlation with rupture than IA size Aspect ratio (AR), defined as IA height divided by neck diameter, is the most commonly studied shape parameter Although most findings affirm its importance, they do not converge on a common threshold value (2, 22, 26, 27, 29) Other, more sophisticated, shape parameters such as undulation index (UI), nonsphericity index (NSI), and ellipticity index (EI) have been proposed (22) in an attempt to account for the three-dimensional (3D) nature of IA Such 3D parameters show promise to be better predictors than lower-dimensional parameters such as size or AR, and they are further examined in the current study Previous studies have also investigated additional factors that correlate with IA rupture risk, such as familial preponderance, smoking, hypertension, female sex, connective tissue disorder, aneurysm growth rate, and presence of multiple IAs (15-17, 32) However, these studies have not yielded quantifiable metrics that can be readily integrated into the clinical decision-making process Adding complexity from such diverse variables into our current study would make risk assessment analysis unwieldy Currently, morphometric evaluation, typically using size alone, is the mainstay of applied aneurysm rupture risk assessment in day-to-day clinical practice Our aim is to improve such morphological evaluation and better the accuracy of aneurysm rupture risk assessment, something that is fundamental to the current practice of cerebrovascular neurosurgery A limitation of previous morphology-based rupture risk studies, including those investigating 3D parameters, is that the geometry of the parent artery is typically ignored Parent artery geometry has a significant influence on the resultant IA hemodynamics and, consequently, the rupture risk Castro et al (4) have demonstrated that upstream vessel tortuosity can critically influence intra-aneurysmal hemodynamics Hassan et al (11) observed that a greater parent vessel incidence angle shifts the high WSS area toward the aneurysm dome, where rupture-prone blebs often are present, whereas Hoi et al (13) noted that highly curved parent vessels subject IAs to higher hemodynamic stresses at the inflow zone that might promote growth or rupture Thus, parent vessel geometry should be accounted for when defining morphological parameters for IA rupture risk prediction Furthermore, numerous studies have observed a connection between IA rupture risk and vessel location (3, 4, 9, 21, 26, 30) Because vessel location is strongly related to vessel geometry, this finding affirms the importance of vessel geometry for IA rupture risk Incorporating parent vessel geometry in morphology parameters can, at least to some extent, capture the influence of IA location as well In the current study, we address the above-mentioned issues and define three new morphology parameters that incorporate IA parent vessel geometry We analyze a group of 45 IAs (20 ruptured, 25 unruptured) to evaluate new IA rupture parameters, in comparison with five “traditional” parameters that have been described in earlier studies

US Multicenter Experience With the Wingspan Stent System for the Treatment of Intracranial Atheromatous Disease Periprocedural Results

Abstract: Background and Purpose— The current report details our initial periprocedural experience with Wingspan (Boston Scientific/Target), the first self-expanding stent system designed for the treatment of intracranial atheromatous disease. Methods— All patients undergoing angioplasty and stenting with the Gateway balloon–Wingspan stent system were prospectively tracked. Results— During a 9-month period, treatment with the stent system was attempted in 78 patients (average age, 63.6 years; 33 women) with 82 intracranial atheromatous lesions, of which 54 were ≥70% stenotic. Eighty-one of 82 lesions were successfully stented (98.8%) during the first treatment session. In 1 case, the stent could not be delivered across the lesion; the patient was treated solely with angioplasty and stented at a later date. Lesions treated involved the internal carotid (n=32; 8 petrous, 10 cavernous, 11 supraclinoid segment, 3 terminus), vertebral (n=14; V4 segment), basilar (n=14), and middle cerebral (n=22) arteries. Mean±SD pretr...

Guidelines for the Early Management of Patients With Acute Ischemic Stroke A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

Abstract: Background and Purpose—The authors present an overview of the current evidence and management recommendations for evaluation and treatment of adults with acute ischemic stroke. The intended audienc...

Heart Disease and Stroke Statistics—2017 Update: A Report From the American Heart Association

Abstract: WRITING GROUP MEMBERS Emelia J. Benjamin, MD, SCM, FAHA Michael J. Blaha, MD, MPH Stephanie E. Chiuve, ScD Mary Cushman, MD, MSc, FAHA Sandeep R. Das, MD, MPH, FAHA Rajat Deo, MD, MTR Sarah D. de Ferranti, MD, MPH James Floyd, MD, MS Myriam Fornage, PhD, FAHA Cathleen Gillespie, MS Carmen R. Isasi, MD, PhD, FAHA Monik C. Jiménez, ScD, SM Lori Chaffin Jordan, MD, PhD Suzanne E. Judd, PhD Daniel Lackland, DrPH, FAHA Judith H. Lichtman, PhD, MPH, FAHA Lynda Lisabeth, PhD, MPH, FAHA Simin Liu, MD, ScD, FAHA Chris T. Longenecker, MD Rachel H. Mackey, PhD, MPH, FAHA Kunihiro Matsushita, MD, PhD, FAHA Dariush Mozaffarian, MD, DrPH, FAHA Michael E. Mussolino, PhD, FAHA Khurram Nasir, MD, MPH, FAHA Robert W. Neumar, MD, PhD, FAHA Latha Palaniappan, MD, MS, FAHA Dilip K. Pandey, MBBS, MS, PhD, FAHA Ravi R. Thiagarajan, MD, MPH Mathew J. Reeves, PhD Matthew Ritchey, PT, DPT, OCS, MPH Carlos J. Rodriguez, MD, MPH, FAHA Gregory A. Roth, MD, MPH Wayne D. Rosamond, PhD, FAHA Comilla Sasson, MD, PhD, FAHA Amytis Towfighi, MD Connie W. Tsao, MD, MPH Melanie B. Turner, MPH Salim S. Virani, MD, PhD, FAHA Jenifer H. Voeks, PhD Joshua Z. Willey, MD, MS John T. Wilkins, MD Jason HY. Wu, MSc, PhD, FAHA Heather M. Alger, PhD Sally S. Wong, PhD, RD, CDN, FAHA Paul Muntner, PhD, MHSc On behalf of the American Heart Association Statistics Committee and Stroke Statistics Subcommittee Heart Disease and Stroke Statistics—2017 Update

Heart Disease and Stroke Statistics—2016 Update: A Report From the American Heart Association

Abstract: Author(s): Writing Group Members; Mozaffarian, Dariush; Benjamin, Emelia J; Go, Alan S; Arnett, Donna K; Blaha, Michael J; Cushman, Mary; Das, Sandeep R; de Ferranti, Sarah; Despres, Jean-Pierre; Fullerton, Heather J; Howard, Virginia J; Huffman, Mark D; Isasi, Carmen R; Jimenez, Monik C; Judd, Suzanne E; Kissela, Brett M; Lichtman, Judith H; Lisabeth, Lynda D; Liu, Simin; Mackey, Rachel H; Magid, David J; McGuire, Darren K; Mohler, Emile R; Moy, Claudia S; Muntner, Paul; Mussolino, Michael E; Nasir, Khurram; Neumar, Robert W; Nichol, Graham; Palaniappan, Latha; Pandey, Dilip K; Reeves, Mathew J; Rodriguez, Carlos J; Rosamond, Wayne; Sorlie, Paul D; Stein, Joel; Towfighi, Amytis; Turan, Tanya N; Virani, Salim S; Woo, Daniel; Yeh, Robert W; Turner, Melanie B; American Heart Association Statistics Committee; Stroke Statistics Subcommittee

Heart Disease and Stroke Statistics—2013 Update A Report From the American Heart Association

Abstract: Author(s): Go, Alan S; Mozaffarian, Dariush; Roger, Veronique L; Benjamin, Emelia J; Berry, Jarett D; Borden, William B; Bravata, Dawn M; Dai, Shifan; Ford, Earl S; Fox, Caroline S; Franco, Sheila; Fullerton, Heather J; Gillespie, Cathleen; Hailpern, Susan M; Heit, John A; Howard, Virginia J; Huffman, Mark D; Kissela, Brett M; Kittner, Steven J; Lackland, Daniel T; Lichtman, Judith H; Lisabeth, Lynda D; Magid, David; Marcus, Gregory M; Marelli, Ariane; Matchar, David B; McGuire, Darren K; Mohler, Emile R; Moy, Claudia S; Mussolino, Michael E; Nichol, Graham; Paynter, Nina P; Schreiner, Pamela J; Sorlie, Paul D; Stein, Joel; Turan, Tanya N; Virani, Salim S; Wong, Nathan D; Woo, Daniel; Turner, Melanie B; American Heart Association Statistics Committee and Stroke Statistics Subcommittee

Heart Disease and Stroke Statistics—2011 Update A Report From the American Heart Association

Abstract: Rosamond, Paul D. Sorlie, Randall S. Stafford, Tanya N. Turan, Melanie B. Turner, Nathan D. Dariush Mozaffarian, Michael E. Mussolino, Graham Nichol, Nina P. Paynter, Wayne D. Ariane Marelli, David B. Matchar, Mary M. McDermott, James B. Meigs, Claudia S. Moy, Lackland, Judith H. Lichtman, Lynda D. Lisabeth, Diane M. Makuc, Gregory M. Marcus, John A. Heit, P. Michael Ho, Virginia J. Howard, Brett M. Kissela, Steven J. Kittner, Daniel T. Caroline S. Fox, Heather J. Fullerton, Cathleen Gillespie, Kurt J. Greenlund, Susan M. Hailpern, Todd M. Brown, Mercedes R. Carnethon, Shifan Dai, Giovanni de Simone, Earl S. Ford, Véronique L. Roger, Alan S. Go, Donald M. Lloyd-Jones, Robert J. Adams, Jarett D. Berry, Association 2011 Update : A Report From the American Heart −− Heart Disease and Stroke Statistics