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E Sander Connolly

Publications and source records attributed to E Sander Connolly.

At least 37 records · Page 2Linked to original sources

Prediction of symptomatic vasospasm after subarachnoid hemorrhage: the modified fisher scale.

OBJECTIVE: We developed a modification of the Fisher computed tomographic rating scale and compared it with the original Fisher scale to determine which scale best predicts symptomatic vasospasm after subarachnoid hemorrhage. METHODS: We analyzed data from 1355 subarachnoid hemorrhage patients in the placebo arm of four randomized, double-blind, placebo-controlled studies of tirilazad. Modified Fisher computed tomographic grades were calculated on the basis of the presence of cisternal blood and intraventricular hemorrhage. Crude odds ratios (OR) reflecting the risk of developing symptomatic vasospasm were calculated for each scale level, and adjusted ORs expressing the incremental risk were calculated after controlling for known predictors of vasospasm. RESULTS: Of 1355 patients, 451 (33%) developed symptomatic vasospasm. For the modified Fisher scale, compared with Grade 0 to 1 patients, the crude OR for vasospasm was 1.6 (95% confidence interval [CI], 1.0-2.5) for Grade 2, 1.6 (95% CI, 1.1-2.2) for Grade 3, and 2.2 (95% CI, 1.6-3.1) for Grade 4. For the original Fisher scale, referenced to Grade 1, the OR for vasospasm was 1.3 (95% CI, 0.7-2.2) for Grade 2, 2.2 (95% CI, 1.4-3.5) for Grade 3, and 1.7 (95% CI, 1.0-3.0) for Grade 4. Early angiographic vasospasm, history of hypertension, neurological grade, and elevated admission mean arterial pressure were identified as risk factors for symptomatic vasospasm. After adjusting for these variables, the modified Fisher scale remained a significant predictor of vasospasm (adjusted OR, 1.28; 95% CI, 1.06-1.54), whereas the original Fisher scale was not. CONCLUSION: The modified Fisher scale, which accounts for thick cisternal and ventricular blood, predicts symptomatic vasospasm after subarachnoid hemorrhage more accurately than original Fisher scale.

Humans↗

Prognostic significance of continuous EEG monitoring in patients with poor-grade subarachnoid hemorrhage.

INTRODUCTION: Predicting outcome in patients with poor-grade subarachnoid hemorrhage (SAH) may help guide therapy and assist in family discussions. The objective of this study was to determine if continuous electroencephalogram (cEEG) monitoring results are predictive of 3-month outcome in critically ill patients with SAH. METHODS: We prospectively studied 756 patients with SAH over a 7-year period. Functional outcome was assessed at 3 months with the modified Rankin Scale (mRS). Patients that underwent cEEG monitoring were retrospectively identified and EEG findings were collected. Multivariate logistic regression analysis was performed to identify EEG findings associated with poor outcome, defined as mRS 4 to 6 (dead or moderately to severely disabled). RESULTS: In 116 patients with SAH, cEEG monitoring and 3-month mRS were available. Of these patients, 88% had a Hunt & Hess grade of 3 or worse on admission. After controlling for age, Hunt & Hess grade, and presence of intraventricular hemorrhage on admission CT scan, poor outcome was associated with the absence of sleep architecture (80 versus 47%; odds ratio [OR] 4.3, 95%-confidence interval [CI] 1.1-17.2) and the presence of periodic lateralized epileptiform discharges (PLEDS) (91 versus 66% OR 18.8, 95%-CI 1.6-214.6). In addition, outcome was poor in all patients with absent EEG reactivity (n = 8), generalized periodic epileptiform discharges (n = 12), or bilateral independent PLEDs (n = 5), and in 92% (11 of 12) of patients with nonconvulsive status epilepticus. CONCLUSIONS: cEEG monitoring provides independent prognostic information in patients with poor-grade SAH, even after controlling for clinical and radiological findings. Unfavorable findings include periodic epileptiform discharges, electrographic status epilepticus, and the absence of sleep architecture.

Cohort Studies↗

Preclinical evaluation of the neuroprotective effect of soluble complement receptor type 1 in a nonhuman primate model of reperfused stroke.

OBJECT: Postischemic cerebral inflammatory injury has been extensively investigated in an effort to develop effective neuroprotective agents. The complement cascade has emerged as an important contributor to postischemic neuronal injury. Soluble complement receptor Type 1 (sCR1), a potent inhibitor of complement activation, has been shown to reduce infarct volume and improve functional outcome after murine stroke. Given numerous high-profile failures to translate promising antiinflammatory strategies from the laboratory to the clinic and given the known species-specificity of the complement cascade, the authors sought to evaluate the neuroprotective effect of sCR1 in a nonhuman primate model of stroke. METHODS: A total of 48 adult male baboons (Papio anubis) were randomly assigned to receive 15 mg/kg of sCR1 or vehicle. The animals were subjected to 75 minutes of middle cerebral artery occlusion/reperfusion. Perioperative blood samples were analyzed for total complement activity by using a CH50 assay. Infarct volume and neurological scores were assessed at the time the animals were killed, and immunohistochemistry was used to determine cerebral drug penetration and C1q deposition. An interim futility analysis led to termination of the trial after study of 12 animals. Total serum complement activity was significantly depressed in the sCR1-treated animals compared with the controls. Immunostaining also demonstrated sCR1 deposition in the ischemic hemispheres of treated animals. Despite these findings, there were no significant differences in infarct volume or neurological score between the sCR1--and vehicle-treated cohorts. CONCLUSIONS: A preischemic bolus infusion of sCR1, the most effective means of administration in mice, was not neuroprotective in a primate model. This study illustrates the utility of a translational primate model of stroke in the assessment of promising antiischemic agents prior to implementation of large-scale clinical trials.

Animals↗

Elevations in preoperative monocyte count predispose to acute neurocognitive decline after carotid endarterectomy for asymptomatic carotid artery stenosis.

BACKGROUND AND PURPOSE: Although the incidence of major stroke attributable to carotid endarterectomy (CEA) is low (1% to 2%), approximately 25% of patients experience subtle postoperative neurocognitive dysfunction. This study examines whether preoperative leukocyte profiles predict cognitive outcome in asymptomatic CEA patients. METHODS: Sixty-nine asymptomatic CEA patients underwent neuropsychometric testing preoperatively and on postoperative day 1 (POD1). Preoperative white blood cell counts and differentials were obtained. Logistic regression was performed for risk factors for neurocognitive decline. Variables achieving univariate P<0.10 were included in multivariate analysis. RESULTS: Eighteen (26%) patients experienced neurocognitive decline on POD1; multivariate analysis demonstrated that preoperative monocyte count (P=0.011) and age (P=0.02) independently predicted outcome. CONCLUSIONS: Preoperative monocyte count and age are independently associated with acute neurocognitive decline after CEA for asymptomatic stenosis.

Age Factors↗

Cardiac troponin elevation, cardiovascular morbidity, and outcome after subarachnoid hemorrhage.

BACKGROUND: Cardiac troponin I (cTI) release occurs frequently after subarachnoid hemorrhage (SAH) and has been associated with a neurogenic form of myocardial injury. The prognostic significance and clinical impact of these elevations remain poorly defined. METHODS AND RESULTS: We studied 253 SAH patients who underwent serial cTI measurements for clinical or ECG signs of potential cardiac injury. These patients were drawn from an inception cohort of 441 subjects enrolled in the Columbia University SAH Outcomes Project between November 1998 and August 2002. Peak cTI levels were divided into quartiles or classified as undetectable. Adverse in-hospital events were prospectively recorded, and outcome at 3 months was assessed with the modified Rankin Scale. Admission predictors of cTI elevation included poor clinical grade, intraventricular hemorrhage, loss of consciousness at ictus, global cerebral edema, and a composite score of physiological derangement (all P< or =0.01). Peak cTI level was associated with an increased risk of echocardiographic left ventricular dysfunction (odds ratio [OR], 1.3 per quintile; 95% CI, 1.0 to 1.7; P=0.03), pulmonary edema (OR, 2.1 per quintile; 95% CI, 1.6 to 2.7; P<0.001), hypotension requiring pressors (OR, 1.9 per quintile; 95% CI, 1.5 to 2.3; P<0.001), and delayed cerebral ischemia from vasospasm (OR, 1.3 per quintile; 95% CI, 1.07 to 1.7; P=0.01). Peak cTI levels were predictive of death or severe disability at discharge after controlling for age, clinical grade, and aneurysm size (adjusted OR, 1.4 per quintile; 95% CI, 1.1 to 1.9; P=0.02), but this association was no longer significant at 3 months. CONCLUSIONS: cTI elevation after SAH is associated with an increased risk of cardiopulmonary complications, delayed cerebral ischemia, and death or poor functional outcome at discharge.

Adult↗

Determinants of staged endovascular and surgical treatment outcome of brain arteriovenous malformations.

BACKGROUND AND PURPOSE: Therapy of brain arteriovenous malformations (AVMs) often requires the combination of different treatment modalities. Independently assessed data on neurologic outcome after multidisciplinary AVM therapy are scarce. METHODS: The 119 consecutive patients (49% women, mean age 34+/-13 years) with brain AVMs receiving endovascular embolization followed by surgical treatment were analyzed. Neurologic impairment was assessed prospectively by a neurologist using the modified Rankin Scale (mRS) before, during, and after completed AVM therapy. The association of demographic, clinical, and morphologic characteristics with new treatment-related neurologic deficits was calculated. RESULTS: The 119 patients were treated with 240 superselective embolizations (median, 2; range, 1 to 8) using n-butyl cyanoacrylate. Mean follow-up time after surgery was 9.6+/-13.2 months. On the Spetzler-Martin scale, 8% of the AVMs were grade 1, 27% grade 2, 40% grade 3, 22% grade 4, and 3% grade 5. Disabling treatment-related complications (mRS> or =3) occurred in 5% (95% confidence interval [CI], 1% to 9%) of the patients. Nondisabling new deficits were observed in another 42% (95% CI, 33% to 51%). No patient died. Nonhemorrhagic AVM presentation (odds ratio [OR], 5.00; 95% CI, 1.75 to 14.29), deep venous drainage (OR, 3.09; 95% CI, 1.43 to 6.64), AVM location in an eloquent brain region (OR, 2.42; 95% CI, 1.10 to 5.33), and large AVM size (OR, 1.05; 95% CI, 1.01 to 1.09) were independently associated with new treatment-related deficits. CONCLUSIONS: Our results suggest an increased treatment risk for patients with previously unbled AVMs from combined endovascular and surgical AVM therapy. Additional risk factors for treatment-related neurologic deficits may be large AVM size, deep venous drainage, and AVM location in eloquent brain regions.

Adolescent↗

C1q-deficiency is neuroprotective against hypoxic-ischemic brain injury in neonatal mice.

BACKGROUND AND PURPOSE: This study was undertaken to determine whether the initial component of the classical complement (C) activation pathway contributes to hypoxic-ischemic brain injury in neonatal mice. METHODS: Hypoxia-ischemia (HI) was produced in C1q(-/-) and wild-type (WT) neonatal mice. At 24 hours after HI, neonatal mouse reflex performance and cerebral infarct volume were assessed. Long-term outcomes were measured by water-maze performance and degree of cerebral atrophy at 7 to 8 weeks after HI. Activation of circulating neutrophils, and C1q, C3, and neutrophil deposition in brains were examined. RESULTS: C1q(-/-) mice were significantly protected against HI (mean+/-SE infarct volume in C1q(-/-) mice=17.3+/-5.5% versus 53.6+/-6.8% in WT mice; P<0.0001) and exhibited significantly less neurofunctional deficit compared with WT mice. Immunostaining revealed significantly greater deposition of C3 (and C1q) as well as granulocytes in the infarcted brains in WT mice compared with C1q(-/-) animals. Activation of circulating leukocytes was significantly decreased in C1q(-/-) mice compared with WT mice, which correlated strongly (r=0.7) with cerebral infarct volumes. CONCLUSIONS: Cerebral deposition of C1q and C3 after hypoxic-ischemic insult is associated with significantly greater neurologic damage in WT mice compared with C1q(-/-) mice, providing strong evidence that the classical C pathway contributes to the hypoxic-ischemic brain injury. Significantly decreased activation of circulating neutrophils associated with diminished local accumulation and attenuation of brain injury in C1q(-/-) mice suggests a potential cellular mechanism by which C1q mediates neurodegeneration in HI.

Animals↗

Phenytoin exposure is associated with functional and cognitive disability after subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: Phenytoin (PHT) is routinely used for seizure prophylaxis after subarachnoid hemorrhage (SAH), but may adversely affect neurologic and cognitive recovery. METHODS: We studied 527 SAH patients and calculated a "PHT burden" for each by multiplying the average serum level of PHT by the time in days between the first and last measurements, up to a maximum of 14 days from ictus. Functional outcome at 14 days and 3 months was measured with the modified Rankin scale, with poor functional outcome defined as dependence or worse (modified Rankin Scale > or =4). We assessed cognitive outcomes at 14 days and 3 months with the telephone interview for cognitive status. RESULTS: PHT burden was associated with poor functional outcome at 14 days (OR, 1.5 per quartile; 95% CI, 1.3 to 1.8; P<0.001), although not at 3 months (P=0.09); the effect remained (OR, 1.6 per quartile; 95% CI, 1.2 to 2.1; P<0.001) after correction for admission Glasgow Coma Scale, fever, stroke, age, National Institutes of Health Stroke Scale > or =10, hydrocephalus, clinical vasospasm, and aneurysm rebleeding. Seizure in hospital (OR, 4.1; 95% CI, 1.5 to 11.1; P=0.002) was associated with functional disability in a univariate model only. Higher quartiles of PHT burden were associated with worse telephone interview for cognitive status scores at hospital discharge (P<0.001) and at 3 months (P=0.003). CONCLUSIONS: Among patients treated with PHT, burden of exposure to PHT predicts poor neurologic and cognitive outcome after SAH.

Cognition Disorders↗

The natural history of intracranial carotid artery atherosclerosis.

Intracranial atherosclerosis is the cause of a significant number of strokes. Despite maximal medical therapy, this disease continues to carry a poor prognosis. The authors reviewed studies in which the outcomes after conservative management in patients with intracranial carotid artery atherosclerosis were reported. Analysis of the literature demonstrates that maximal medical therapy frequently fails with this disease, leaving patients at high risk for cerebral infarction and death. A better understanding of the pathophysiological aspects and natural history of this condition may serve to guide clinical decision making and the choice of therapeutic options in this patient population.

Carotid Artery Diseases↗

Current endovascular treatment options for intracranial carotid artery atherosclerosis.

A substantial number of strokes are caused by intracranial atherosclerosis, a disease that traditionally has been treated medically. Recent technological advancements, however, have revolutionized the treatment of this condition by enabling the use of endovascular methods. In this paper the authors focus on the internal carotid artery, and review relevant studies concerning angioplasty with stent placement for the management of intracranial atherosclerosis in this vessel. With continued experience and a multidisciplinary approach in the evaluation of these patients, favorable outcomes may be achieved.

Angioplasty↗

Predictors and impact of aneurysm rebleeding after subarachnoid hemorrhage.

BACKGROUND: Aneurysm rebleeding has historically been an important cause of mortality after subarachnoid hemorrhage (SAH). OBJECTIVE: To describe the frequency and impact of rebleeding in the modern era of aneurysm care, which emphasizes early surgical or endovascular treatment. DESIGN: Inception cohort. SETTING: Tertiary care medical center. PATIENTS: A total of 574 patients enrolled in the Columbia University SAH Outcomes Project between August 1996 and June 2002. Early aneurysm repair was performed whenever feasible. MAIN OUTCOME MEASURES: Rebleeding was defined by prespecified clinical and radiographic criteria, excluding prehospital, intraprocedural, and postrepair events. Functional outcome was assessed at 3 months with the modified Rankin Scale. Multiple logistic regression was used to identify predictors of rebleeding, poor functional outcome, and mortality. RESULTS: Rebleeding occurred in 40 (6.9%) of the 574 patients; most cases (73%) occurred within 3 days of ictus. Hunt-Hess grade on admission (odds ratio [OR], 1.92 per grade; 95% confidence interval [CI], 1.33-2.75; P<.001) and maximal aneurysm diameter (OR, 1.07/mm; 95% CI, 1.01-1.13; P = .005) were independent predictors of rebleeding. After controlling for Hunt-Hess grade and aneurysm size, rebleeding was associated with a markedly reduced chance of survival with functional independence (modified Rankin Scale score, </=4; OR, 0.08; 95% CI, 0.02-0.34) at 3 months. CONCLUSIONS: Despite an aggressive management strategy, rebleeding still occurred in 6.9% of patients and was associated with a dismal outcome. Poor Hunt-Hess grade and larger aneurysm size are related to rebleeding. Pharmacologic therapy to reduce the risk of rebleeding before aneurysm repair, particularly in patients with poor grade neurologic status and large aneurysms, deserves renewed attention.

Aged↗

Toward objective quantification of perfusion-weighted computed tomography in subarachnoid hemorrhage: quantification of symmetry and automated delineation of vascular territories.

RATIONALE AND OBJECTIVES: Perfusion-weighted computed tomography (CTP) is a relatively recent innovation that estimates a value for cerebral blood flow (CBF) using a series of axial head CT images tracking the time course of a signal from an intravenous contrast bolus. MATERIALS AND METHODS: CTP images were obtained using a standard imaging protocol and were analyzed using commercially available software. A novel computer-based method was used for objective quantification of side-to-side asymmetries of CBF values calculated from CTP images. RESULTS: Our method corrects for the inherent variability of the CTP methodology seen in the subarachnoid hemorrhage (SAH) patient population to potentially aid in the diagnosis of cerebral vasospasm (CVS). This method analyzes and quantifies side-to-side asymmetry of CBF and presents relative differences in a construct termed a Relative Difference Map (RDM). To further automate this process, we have developed a unique methodology that enables a computer to delineate vascular territories within a brain image, regardless of the size and shape of the brain. CONCLUSIONS: While both the quantification of image symmetry using RDMs and the automated assignment of vascular territories were initially designed for the analysis of CTP images, it is likely that they will be useful in a variety of applications.

Adult↗

Activation of c-Jun and ATF-2 in primate motor cranial nerve nuclei is not associated with apoptosis following axotomy.

Nerve transection induces complex changes in gene regulation and expression that can have profound phenotypic effects on the fate of axotomized neurons. The transcription factors c-Jun and ATF-2 (activating transcription factor-2) are components of a regulatory network that mediates survival, regeneration, and apoptosis following axotomy in rodents. The activation and function of c-Jun and ATF-2 after nerve injury have not been examined in primates. Using a novel model of cranial nerve injury in baboons, we have examined the temporality of c-Jun activation (phosphorylation) in cranial nerve (CN) III and CN VI neurons and ATF-2 activation in CN VI neurons at 2, 4, and 9 days post-injury by immunohistochemistry. Furthermore, we have addressed whether the activation of these factors is associated with apoptosis by the TUNEL assay. We report that activated c-Jun is present in CN III and CN VI neurons ipsilateral to axotomy at 2, 4, and 9 days post-injury, but not in neurons contralateral to injury. Additionally, CN VI neurons ipsilateral to injury at 4 and 9 days contain activated ATF-2. Furthermore, no evidence of TUNEL reactivity was observed in either nucleus, regardless of laterality, at any of the examined time points. These findings suggest that activation of both c-Jun and ATF-2 does not mediate apoptosis in axotomized primate CN III and CN VI neurons at time points up to 9 days. This report serves as a basic inquiry into the neuronal response to cranial nerve injury in primates.

Abducens Nerve↗

Intensive care unit management of interventional neuroradiology patients.

The management of interventional neurologic patients in the intensive care unit is based on their underlying disease for the most part. Patients with ischemic stroke are largely managed like patients with ischemic stroke who have not undergone interventional procedures, and the same is true for those with an aneurysmal subarachnoid hemorrhage or intracerebral hemorrhage secondary to an arteriovenous malformation, for example.Having said this, there are some special considerations that require special mention when it comes to managing patients after catheter-based procedures.

Brain Ischemia↗

Co-registration of radiographic and pathologic infarct territory in a non-human primate model of stroke.

OBJECTIVES: Infarct volume correlation using magnetic resonance imaging (MRI) and pathology specimens enables exact tissue localization of cerebral injury following experimental stroke. We describe a protocol that enables co-registration of radiographic signal change and histologic ischemia in a non-human primate model of stroke. METHODS: One male baboon underwent left middle cerebral artery territory occlusion/reperfusion. MRI [5 mm axial T2 weighted (T2W) slices] was carried out 9 days post-ischemia after which the animal was killed. Immediately post-mortem, the whole brain was perfused and fixed in paraformaldehyde and sliced into 5 mm axial sections that corresponded to those demonstrated on MRI. Slices (40 microm) were obtained from each section and were then stained using Luxol hematoxylin and eosin. RESULTS: The relative area of hyperintensity demonstrated on T2W MRI approximates, in size and location, the region of infarct on gross pathology. This was confirmed microscopically. DISCUSSION: With the use of advanced imaging modalities, this co-registration technique affords the capacity to differentiate ischemic core, penumbra, and uninjured cortex following experimental stroke. Such a precise delineation enables immunohistochemical analysis of a wide variety of substrates in each of the aforementioned regions.

Animals↗

Physicochemical characteristics of soluble oligomeric Abeta and their pathologic role in Alzheimer's disease.

Extracellular fibrillar amyloid deposits are prominent and universal Alzheimer's disease (AD) features, but senile plaque abundance does not always correlate directly with the degree of dementia exhibited by AD patients. The mechanism(s) and dynamics of Abeta fibril genesis and deposition remain obscure. Enhanced Abeta synthesis rates coupled with decreased degradative enzyme production and accumulating physical modifications that dampen proteolysis may all enhance amyloid deposit formation. Amyloid accumulation may indirectly exert the greatest pathologic effect on the brain vasculature by destroying smooth muscle cells and creating a cascade of negative impacts on cerebral blood flow. The most visible manifestation of amyloid dis-equilibrium could actually be a defense mechanism employed to avoid serious vascular wall degradation while the major toxic effects to the gray and white matter neurons are mediated by soluble oligomeric Abeta peptides with high beta-sheet content. The recognition that dynamic soluble oligomeric Abeta pools exist in AD and are correlated to disease severity led to neurotoxicity and physical conformation studies. It is now recognized that the most basic soluble Abeta peptides are stable dimers with hydrophobic regions sequestered from the aqueous environment and are capable of higher order aggregations. Time course experiments employing a modified ELISA method able to detect Abeta oligomers revealed dynamic intermolecular interactions and additional experiments physically confirmed the presence of stable amyloid multimers. Amyloid peptides that are rich in beta-sheet structure are capable of creating toxic membrane ion channels and a capacity to self-assemble as annular structures was confirmed in vitro using atomic force microscopy. Biochemical studies have established that soluble Abeta peptides perturb metabolic processes, provoke release of deleterious reactive compounds, reduce blood flow, induce mitochondrial apoptotic toxicity and inhibit angiogenesis. While there is no question that gross amyloid deposition does contribute to AD pathology, the destructive potential now associated with soluble Abeta suggests that treatment strategies that target these molecules may be efficacious in preventing some of the devastating effects of AD.

3-Hydroxyacyl CoA Dehydrogenases↗

Dobutamine versus milrinone after subarachnoid hemorrhage.

OBJECTIVE: Neurogenic stunned myocardium is a well-recognized complication of subarachnoid hemorrhage. Dobutamine and milrinone are both used for neurogenic stunned myocardium, but there are few data comparing them after subarachnoid hemorrhage. METHODS: We compared the physiological dose response of dobutamine and milrinone in patients with subarachnoid hemorrhage requiring a pulmonary artery catheter. We located 11 patients who received either inotrope. Physiological data were fitted to a mixed model accounting for drug, dose, and between-patient variation. RESULTS: There were 11 patients who had 152 pulmonary artery catheter measurements. Two received both inotropes (but not within 4 h of each other), 2 only milrinone, and 7 only dobutamine. The groups had similar clinical and physiological characteristics. After adjustment for vasopressin, milrinone was significantly more potent in increasing cardiac output (P <0.0001) and stroke volume (P=0.03), while decreasing vascular resistance (P <0.0001) and systolic blood pressure (P=0.008), than dobutamine. CONCLUSION: These data suggest that milrinone and dobutamine should be used in different clinical situations. Milrinone may be more effective in patients with severely depressed systolic function but who have at least normal vascular resistance and blood pressure and in whom raising cardiac output is the primary goal. Dobutamine may be superior when vascular resistance or blood pressure is low.

Adrenergic beta-Agonists↗