PubMed Health⌕ Search

Biomedical subjects

T Brott

Publications and source records attributed to T Brott.

At least 37 records · Page 2Linked to original sources
PubMed1999

Early surgical treatment for supratentorial intracerebral hemorrhage: a randomized feasibility study.

BACKGROUND AND PURPOSE: The safety and the effectiveness of the surgical treatment of spontaneous intracerebral hemorrhage (ICH) remain controversial. To investigate the feasibility of urgent surgical evacuation of ICH, we conducted a small, randomized feasibility study of early surgical treatment versus current nonoperative management in patients with spontaneous supratentorial ICH. METHODS: Patients with spontaneous supratentorial ICH who presented to 1 university and 2 community hospitals were randomized to surgical treatment or best medical treatment. Principal eligibility criteria were ICH volume >10 cm(3) on baseline CT scan with a focal neurological deficit, Glasgow Coma Scale score >4 at the time of enrollment, randomization and therapy within 24 hours of symptom onset, surgery within 3 hours of randomization, and no evidence for ruptured aneurysm or arteriovenous malformation. The primary end point was the 3-month Glasgow Outcome Scale (GOS). A good outcome was defined as a 3-month GOS score >3. RESULTS: Twenty patients were randomized over 24 months, 9 to surgical intervention and 11 to medical treatment. The median time from onset of symptoms to presentation at the treating hospitals was 3 hours and 17 minutes, the time from randomization to surgery was 1 hour and 20 minutes, and the time from onset of symptoms to surgery was 8 hours and 35 minutes. The likelihood of a good outcome (primary outcome measure: GOS score >3) for the surgical treatment group (56%) did not differ significantly from the medical treatment group (36%). There was no significant difference in mortality at 3 months. Analysis of the secondary 3-month outcome measures showed a nonsignificant trend toward a better outcome in the surgical treatment group versus the medical treatment group for the median GOS, Barthel Index, and Rankin Scale and a significant difference in the National Institutes of Health Stroke Scale score (4 versus 14; P=0.04). CONCLUSIONS: Very early surgical treatment for acute ICH is difficult to achieve but feasible at academic medical centers and community hospitals. The trend toward less 3-month morbidity with surgical intervention in patients with spontaneous supratentorial ICH warrants further investigation of very early clot removal in larger randomized clinical trials.

Cerebellar Diseases↗
PubMed1999

Thrombolysis in acute ischemic stroke: controlled trials and clinical experience.

Thrombolytic therapy with recombinant tissue plasminogen activator (rtPA) is approved in the United States for treatment of acute ischemic stroke. Approval was granted after a large, randomized, placebo-controlled study by the National Institute of Neurological Disorders and Stroke (NINDS) showed a significant improvement in 3-month outcomes with rtPA despite a significant risk for symptomatic hemorrhage. Two other trials, the first and second European Cooperative Acute Stroke Study (ECASS I and II), have shown comparable results, but neither was statistically positive for the predefined primary end point. An analysis of the risk/benefit profile of rtPA therapy based on the results of these three trials indicates that the treatment is effective and, when administered within 3 hours of symptom onset at a dose of 0.9 mg/kg, the benefits by far outweigh the risks for eligible patients. Even with the 6-hour time window of the two ECASS trials, a combined analysis of the three studies shows the number of disabled or dead patients to be significantly reduced. Preliminary data collected on the use of rtPA outside of clinical trials in the United States and Europe suggest that, when rtPA is used according to the trial protocol, the risks and benefits are similar to those observed in clinical trials. However, even within the United States, rtPA is underutilized. The most substantial treatment barrier is the narrow time window, which may be expanded if long-term experience shows that this is possible. Most stroke patients arrive at the hospital too late to be eligible for screening and treatment. Education of the public and physicians may help to overcome this difficulty.

Acute Disease↗
PubMed1998

The Greater Cincinnati/Northern Kentucky Stroke Study: preliminary first-ever and total incidence rates of stroke among blacks.

BACKGROUND AND PURPOSE: The Greater Cincinnati/Northern Kentucky Stroke Study was designed to be the first large, population-based metropolitan study of temporal trends in stroke incidence rates and outcome within a biracial population. METHODS: We are identifying all hospitalized and autopsied cases of stroke and transient ischemic attack (TIA) among the 1.3 million inhabitants of a five-county region of Greater Cincinnati/Northern Kentucky for the period 7/1/93-6/30/94. We have already prospectively monitored for out-of-hospital stroke and TIAs for this same time period at 128 screening sites, including a random sample of all primary care physicians and nursing homes in the region. We have already identified all hospitalized and autopsied cases of stroke and TIA among blacks for 1/1/93-6/30/93 and report preliminary incidence rates for this 6-month period. RESULTS: The overall incidence rate for all first-ever hospitalized or autopsied stroke (excluding TIAs) among blacks in the Greater Cincinnati region was 288 per 100000 (95% CI, 250 to 325, age- and sex-adjusted to 1990 US population). The overall incidence rate for first-ever and recurrent stroke (excluding TIAs) was 411 per 100000 (95% CI, 366 to 456). By comparison, the overall incidence rate of first-ever stroke among whites in Rochester, Minn, during the period 1985-1989 was 179 per 100000 (95% CI, 164 to 194, age- and-sex adjusted to 1990 US population). The incidence rates among blacks in Greater Cincinnati were substantially greater than the rates among whites in Rochester, Minn, for all age categories except ages 75 and older, for which the rates were similar. CONCLUSIONS: We conservatively estimate that 731100 first-ever or recurrent strokes occurred in the United States during 1996. Studies of first-ever as well as total stroke among biracial and representative populations are critical for understanding temporal trends in the incidence rate and the burden of stroke in the US population.

Adult↗
PubMed1998

Hypertension and its treatment in the NINDS rt-PA Stroke Trial.

BACKGROUND AND PURPOSE: We examined the frequency, course, and treatment of hypertension in the NINDS rt-PA Stroke Trial. METHODS: Blood pressure (BP) was measured at the time of admission, at randomization, and then 36 times during the first 24 hours after randomization. Patients with a systolic BP of >185 mm Hg and a diastolic BP of >110 mm Hg at admission were defined as hypertensive before randomization, and those with a systolic BP of >180 mm Hg or a diastolic BP of >105 mm Hg within the first 24 hours after randomization were defined as hypertensive after randomization. Standardized clinical assessments were conducted at 24 hours and at 3 months. Post hoc analyses were conducted to evaluate the association of antihypertensive therapy with clinical outcomes. RESULTS: Of the 624 patients, 121(19%) had hypertension on admission and 372 (60%) had hypertension in the 24 hours after randomization. The use of antihypertensive therapy before randomization (tPA 9%, placebo 9%) and after randomization (tPA 24%, placebo 29%) was similar between placebo- and tPA-treated patients. No adverse effects of prerandomization antihypertensive therapy on 3-month favorable outcome were detected for either the placebo- or tPA-treated groups. For placebo patients with hypertension in the 24 hours after randomization, clinical outcome measures were similar for those patients who did and did not receive antihypertensive therapy after randomization (P > or = 0.26); antihypertensive therapy was not associated with declines in BP (P = 0.44) or with abrupt declines (P = 0.14). Those tPA patients who were hypertensive after randomization and received antihypertensive therapy were less likely to have a favorable outcome at 3 months (P < 0.01) than those who were hypertensive and did not receive antihypertensive therapy. CONCLUSIONS: The frequency of hypertension and the use of antihypertensive therapy were similar between the tPA and placebo groups in the NINDS rt-PA Stroke Trial. In the placebo group, antihypertensive therapy was not associated with less favorable outcomes at 3 months; postrandomization antihypertensive therapy was associated with less favorable outcomes for the tPA patients who were hypertensive. However, because of the nonrandomized use of antihypertensive therapy and the many post hoc comparisons leading to type 1 errors, the significance of this observation is unclear. Careful attention to BP and gentle management remain warranted for stroke patients treated with tPA.

Antihypertensive Agents↗
PubMed1997

Asymmetric angioneurotic edema associated with thrombolysis for acute stroke.

We present a case of acute asymmetric angioneurotic edema associated with the use of recombinant tissue plasminogen activator (rtPA) for acute ischemic stroke. rtPA was administered for an acute ischemic stroke in accordance with the recently reported National Institute of Neurological Disorders and Stroke protocol, after which marked asymmetric angioedema requiring upper-airway control developed. Although atypical and anaphylactoid reactions have been reported with the use of rtPA for acute myocardial infarction, to our knowledge this is the first case report of asymmetric angioedema associated with the use of rtPA for acute ischemic stroke.

Acute Disease↗
PubMed1997

Early stroke recognition: developing an out-of-hospital NIH Stroke Scale.

OBJECTIVE: To develop an abbreviated and practical neurologic scale that could assist emergency medical services or triage personnel in identifying patients with stroke. METHODS: A prospective, observational, cohort study was performed at university-based EDs. Participants were 74 patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12-hour shifts in the ED. Scores on the NIH Stroke Scale were obtained for all patients by physicians. Items of this scale were modified and recoded to a binomial (normal or abnormal) scale. Serial univariate analyses using chi 2 were performed to rank items. Recursive partitioning was then performed to develop the decision rule for predicting the presence of stroke. RESULTS: Three items identified 100% of patients with stroke: facial palsy, motor arm, and dysarthria. An Abbreviated NIH Stroke Scale based on these items had a sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital NIH Stroke Scale consisting of facial palsy, motor arm, and a combination of dysarthria and best language items (abnormal speech) had a sensitivity of 100% and a specificity of 88%. CONCLUSION: Using the derivation data set, a proposed Out-of-hospital NIH Stroke Scale had a high sensitivity and specificity for identifying patients with stroke when performed by physicians in this group of 299 ED patients. Prospective studies of other health care professionals using the scale in the out-of-hospital arena are needed.

Adult↗
PubMed1997

Early hemorrhage growth in patients with intracerebral hemorrhage.

BACKGROUND AND PURPOSE: The goal of the present study was to prospectively determine how frequently early growth of intracerebral hemorrhage occurs and whether this early growth is related to early neurological deterioration. METHODS: We performed a prospective observational study of patients with intracerebral hemorrhage within 3 hours of onset. Patients had a neurological evaluation and CT scan performed at baseline, 1 hour after baseline, and 20 hours after baseline. RESULTS: Substantial growth in the volume of parenchymal hemorrhage occurred in 26% of the 103 study patients between the baseline and 1-hour CT scans. An additional 12% of patients had substantial growth between the 1- and 20-hour CT scans. Hemorrhage growth between the baseline and 1-hour CT scans was significantly associated with clinical deterioration, as measured by the change between the baseline and 1-hour Glasgow Coma Scale and National Institutes of Health Stroke Scale scores. No baseline clinical or CT prediction of hemorrhage growth was identified. CONCLUSIONS: Substantial early hemorrhage growth in patients with intracerebral hemorrhage is common and is associated with neurological deterioration. Randomized treatment trials are needed to determine whether this early natural history of ongoing bleeding and frequent neurological deterioration can be improved.

Adult↗
PubMed1997

Patients' awareness of stroke signs, symptoms, and risk factors.

BACKGROUND AND PURPOSE: We sought to determine knowledge at the time of symptom onset regarding the signs, symptoms, and risk factors of stroke in patients presenting to the emergency department with potential stroke. METHODS: Patients admitted from the emergency department with possible stroke were identified prospectively. A standardized, structured interview with open-ended questions was performed within 48 hours of symptom onset to assess patients' knowledge base concerning stroke signs, symptoms, and risk factors. RESULTS: Of the 174 eligible patients, 163 patients were able to respond to the interview questions. Of these 163 patients, 39% (63) did not know a single sign or symptom of stroke. Unilateral weakness (26%) and numbness (22%) were the most frequently noted symptoms. Patients aged > or = 65 years were less likely to know a sign or symptom of stroke than those aged < 65 years (percentage not knowing a single sign or symptom, 47% versus 28%, P = .016). Similarly, 43% of patients did not know a single risk factor for stroke. The elderly were less likely to know a risk factor than their younger counterparts. CONCLUSIONS: Almost 40% of patients admitted with a possible stroke did not know the signs, symptoms, or risk factor of a stroke. Further public education is needed to increase awareness of the warning signs and risk factors of stroke.

Aged↗
PubMed1996

Thrombolytic therapy for cerebral infarction.

Until recently, no clinically effective therapy for acute ischemic stroke has been available. Recent advances in the use of thrombolytic therapy for ischemic stroke appear promising in clinical care. As the use of thrombolytic therapy in acute stroke progress, emergency physicians (EPs) will become increasingly involved in its implementation. The EP must be cognizant of both prior and ongoing investigations in acute ischemic stroke therapy. To that end, this article reviews research in the field of thrombolytic therapy for acute ischemic stroke.

Acute Disease↗
PubMed1996

Use of a global test for multiple outcomes in stroke trials with application to the National Institute of Neurological Disorders and Stroke t-PA Stroke Trial.

BACKGROUND: The National Institute of Neurological Disorders and Stroke (NINDS) held a workshop on statistical approaches to analysis of acute stroke trials that have multiple pre-specified outcomes. An objective was to plan for statistical analysis of the NINDS t-PA Stroke Trial, a randomized, double-blind, placebo-controlled trial of recombinant tissue plasminogen activator (rt-PA) for patients with acute ischemic stroke. Treatment success was defined as a "consistent and persuasive difference" in the proportion of patients achieving favorable outcomes on the Barthel Index, Modified Rankin Scale, Glasgow Outcome Scale, and National Institutes of Health Stroke Scale. The Data and Safety Monitoring Committee for the trial recommended this outcome because the committee did not believe that a positive result for a single outcome would provide sufficient evidence of efficacy. SUMMARY OF COMMENT: Workshop participants accepted the global test as a viable approach to testing the primary trial hypothesis. Clinician participants advocated categorizing outcomes as favorable/unfavorable, outcomes more clinically meaningful than continuous outcomes for evaluating a drug with potentially serious side effects. They agreed that a global test was appropriate for ischemic stroke when no single outcome is accepted. Hypothetical, special-case examples illustrate that highly correlated outcomes diminish the power of the global test. NINDS t-PA Stroke Trial data demonstrate the clinical interpretability of the global test. CONCLUSIONS: Workshop participants concluded that a global statistic should be used to test the trial's primary hypothesis accompanied by secondary tests of individual outcomes. Workshop participants recommended familiarizing the clinical/scientific community with the global approach.

Acute Disease↗
PubMed1996

The ABCs of measuring intracerebral hemorrhage volumes.

BACKGROUND AND PURPOSE: Hemorrhage volume is a powerful predictor of 30-day mortality after spontaneous intracerebral hemorrhage (ICH). We compared a bedside method of measuring CT ICH volume with measurements made by computer-assisted planimetric image analysis. METHODS: The formula ABC/2 was used, where A is the greatest hemorrhage diameter by CT, B is the diameter 90 degrees to A, and C is the approximate number of CT slices with hemorrhage multiplied by the slice thickness. RESULTS: The ICH volumes for 118 patients were evaluated in a mean of 38 seconds and correlated with planimetric measurements (R2 = 9.6). Interrater and intrarater reliability were excellent, with an intraclass correlation of .99 for both. CONCLUSIONS: We conclude that ICH volume can be accurately estimated in less than 1 minute with the simple formula ABC/2.

Blood Volume↗
PubMed1996

Prognostic value of the hyperdense middle cerebral artery sign and stroke scale score before ultraearly thrombolytic therapy.

PURPOSE: To determine the relationship between the hyperdense middle cerebral artery sign (HMCAS) and neurologic deficit, as evidenced by the National Institutes of Health (NIH) stroke scale score, and to determine the relationship of the HMCAS and the NIH stroke scale score to arteriographic findings after thrombolytic therapy. METHODS: Fifty-five patients with acute ischemic stroke were rated on the NIH stroke scale, were examined with CT, and were treated with intravenous alteplase within 90 minutes of symptom onset. Presence of the HMCAS was determined on the baseline CT scan by a neuroradiologist blinded to the patient's neurologic deficit. Patients with the HMCAS were compared with those without HMCAS with regard to baseline NIH stroke scale score, 2-hour NIH stroke scale score, findings at posttreatment arteriography, 3-month residual neurologic deficit, and 3-month ischemia volumes as evidenced on CT scans. RESULTS: Eighteen patients (33%) had the HMCAS. These patients had a median baseline NIH stroke scale score of 19.5 compared with a median score of 10 for the patients lacking the HMCAS sign. At 3 months, one (6%) of the HMCAS-positive patients was completely improved neurologically compared with 17 (47%) of the HMCAS-negative patients. Restricting analysis to those patients with a stroke scale score of 10 or greater (n = 37), 18 HMCAS-positive patients showed less early neurologic improvement, were less likely to be completely improved at 3 months, and had larger infarcts compared with the 19 HMCAS-negative patients. Compared with the HMCAS-positive and HMCAS-negative patients with a stroke scale score of 10 or greater, patients with a stroke scale score of less than 10 had fewer occlusive changes of the internal carotid and middle cerebral arteries on posttreatment arteriograms and had a better neurologic recovery at 3 months. CONCLUSION: The presence of the HMCAS on CT scans obtained within 90 minutes of stroke onset is associated with a major neurologic deficit, and in this study it predicted a poor clinical and radiologic outcome after intravenous thrombolytic therapy. However, a major neurologic deficit, defined as a stroke scale score of 10 or more, was better than a positive HMCAS as a predictor of poor neurologic outcome after thrombolytic therapy. Patients with a low stroke scale score (< 10) may benefit from ultraearly intravenous alteplase therapy.

Adult↗
PubMed1995

Medical compared with surgical treatment of asymptomatic carotid artery stenosis.

The Asymptomatic Carotid Atherosclerosis Study (ACAS) results suggest that carotid endarterectomy combined with aspirin and risk factor reduction is superior to aspirin and risk factor reduction is superior to aspirin and risk factor reduction alone in preventing ipsilateral stroke in asymptomatic patients with diameter stenosis of the carotid artery of 60% or more. The absolute risk reduction over 5 years conferred by surgical therapy is modest (5.9%) compared with the risk reduction conferred by surgical therapy for symptomatic carotid disease but compares favorably with the degree of stroke prevention shown for antihypertensive therapy in the elderly. For prevention of stroke in women and for prevention of major stroke, the ACAS results favoring surgery did not reach statistical significance. The combined arteriographic and perioperative surgery-related mortality and stroke rates achieved by the carefully selected surgical teams was low (2.3%). Accordingly, carotid endarterectomy can be recommended for preventing stroke in the setting of hemodynamically significant stenosis when the arteriographic and surgical complication rates can be kept low.

Aspirin↗
PubMed1995

Guidelines for carotid endarterectomy. A multidisciplinary consensus statement from the Ad Hoc Committee, American Heart Association.

BACKGROUND AND PURPOSE: Indications for carotid endarterectomy have engendered considerable debate among experts and have resulted in publication of retrospective reviews, natural history studies, audits of community practice, position papers, expert opinion statements, and finally prospective randomized trials. The American Heart Association assembled a group of experts in a multidisciplinary consensus conference to develop this statement. METHODS: A conference was held July 16-18, 1993, in Park City, Utah, that included recognized experts in neurology, neurosurgery, vascular surgery, and healthcare planning. A program of critical topics was developed, and each expert presented a talk and provided the chairman with a summary statement. From these summary statements a document was developed and edited onsite to achieve consensus before final revision. RESULTS: The first section of this document reviews the natural history, methods of patient evaluation, options for medical management, results of surgical management, data from position statements, and results to date of prospective randomized trials for symptomatic and asymptomatic patients with carotid artery disease. The second section divides 96 potential indications for carotid endarterectomy, based on surgical risk, into four categories: (1) Proven: This is the strongest indication for carotid endarterectomy; data are supported by results of prospective contemporary randomized trials. (2) Acceptable but not proven: a good indication for operation; supported by promising but not scientifically certain data. (3) Uncertain: Data are insufficient to define the risk/benefit ratio. (4) Proven inappropriate: Current data are adequate to show that the risk of surgery outweighs any benefit. CONCLUSIONS: Indications for carotid endarterectomy in symptomatic good-risk patients with a surgeon whose surgical morbidity and mortality rate is less than 6% are as follows. (1) Proven: one or more TIAs in the past 6 months and carotid stenosis > or = 70% or mild stroke within 6 months and a carotid stenosis > or = 70%; (2) acceptable but not proven: TIAs within the past 6 months and a stenosis 50% to 69%, progressive stroke and a stenosis > or = 70%, mild or moderate stroke in the past 6 months and a stenosis 50% to 69%, or carotid endarterectomy ipsilateral to TIAs and a stenosis > or = 70% combined with required coronary artery bypass grafting; (3) uncertain: TIAs with a stenosis < 50%, mild stroke and stenosis < 50%, TIAs with a stenosis < 70% combined with coronary artery bypass grafting, or symptomatic, acute carotid thrombosis; (4) proven inappropriate: moderate stroke with stenosis < 50%, not on aspirin; single TIA, < 50% stenosis, not on aspirin; high-risk patient with multiple TIAs, not on aspirin, stenosis < 50%; high-risk patient, mild or moderate stroke, stenosis < 50%, not on aspirin; global ischemic symptoms with stenosis < 50%; acute dissection, asymptomatic on heparin. Indications for carotid endarterectomy in asymptomatic good-risk patients performed by a surgeon whose surgical morbidity and mortality rate is less than 3% are as follows. (1) Proven: none. As this statement went to press, the National Institute of Neurological Disorders and Stroke issued a clinical advisory stating that the Institute has halted the Asymptomatic Carotid Atherosclerosis Study (ACAS) because of a clear benefit in favor of surgery for patients with carotid stenosis > or = 60% as measured by diameter reduction. When the ACAS report is published, this indication will be recategorized as proven. (2) acceptable but not proven: stenosis > 75% by linear diameter; (3) uncertain: stenosis > 75% in a high-risk patient/surgeon (surgical morbidity and mortality rate > 3%), combined carotid/coronary operations, or ulcerative lesions without hemodynamically significant stenosis; (4) proven inappropriate: operations with a combined stroke morbidity and mortality > 5%.

Arterial Occlusive Diseases↗
PubMed1995

3-D image analysis of intra-cerebral brain hemorrhage from digitized CT films.

A new 3-D technique for the segmentation and quantification of human spontaneous intra-cerebral brain hemorrhage (ICH) is presented in this paper. The algorithm for ICH primary region segmentation uses the spatially weighted K-means histogram-based clustering algorithm. The ICH edema region segmentation algorithm employs an iterative morphological processing of the ICH brain data. A volume rendering technique is used for the effective 3-D visualization of ICH segmented regions. A computer program is developed for use in the human spontaneous ICH study involving a large number of patients. Experimental measurements and visualization results are presented which were computed on real ICH patient brain data.

Algorithms↗