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T R Price

Publications and source records attributed to T R Price.

At least 19 recordsLinked to original sources
PubMed1995

Ulcerated atherosclerotic plaques in the thoracic aorta are associated with cryptogenic stroke: a multiplane transesophageal echocardiographic study.

Atherosclerotic plaque ulcers > or = 2 mm in depth and width in the thoracic aorta have been implicated by autopsy study as a cause of unexplained or cryptogenic ischemic strokes. Transesophageal echocardiography (TEE) allows visualization of complex atherosclerotic lesions of the thoracic aorta. We compared the prevalence of thoracic aorta ulcerated plaques (ulcers > or = 2 mm in both depth and width) in three age-matched groups undergoing multiplane TEE: group 1, 23 patients with cryptogenic ischemic stroke; group 2, 26 patients with known-cause strokes; and group 3, 57 control patients without strokes. TEEs were interpreted in a blinded fashion. Ulcerated plaques were found in 9 (39%) group 1 patients but in only 2 (8%) group 2 patients and in only 4 (7%) group 3 patients (p < 0.001). There was an association between advancing age and the presence of ulcerated plaques (p < 0.02). We conclude that ulcerated atherosclerotic plaques in the thoracic aorta are associated with cryptogenic ischemic stroke and should be considered a potential source of cerebral emboli.

Aged↗
PubMed1995

Microemboli during coronary artery bypass grafting. Genesis and effect on outcome.

Cerebral dysfunction after coronary artery bypass operations represents some of the most serious and costly complications of cardiac surgery. We used transcranial Doppler ultrasonography to detect and quantify the number of microemboli in the right middle cerebral artery of patients undergoing elective first coronary bypass operations (n = 117) and second coronary bypass operations (n = 10). We hypothesized that total microemboli were related to clinical outcome. A 2 MHz transducer was positioned in front of the ear above the zygomatic arch and depth gated to 50 mm. Microemboli were recorded as perturbations of the blood flow velocity in the middle cerebral artery and aurally monitored. Each episode of microembolism was specified both by clock time and as a perfusion or surgical event. Forty-one patients (32%) completed neuropsychologic evaluation with a battery of tests for cognitive function. Anxiety states and traits were also assessed. The distribution of microembolism showed that there were three groups of patients: < 30 microemboli (n = 83); 30 to 59 (n = 24); and > 60 (n = 20). Seven of 10 patients with cerebral complications (stroke, coma, delirium, aberrant behavior) were in the > 60 microemboli group. Those with cerebral complications had 20.7 +/- 4.5 microemboli from perfusion and 57.4 +/- 15.6 from surgical events. The 13 patients in the > 60 microemboli group without central nervous system symptoms had 95.5 +/- 19.5 microemboli from perfusion and 36.0 +/- 6.9 from surgical events. Neuropsychologic scores were most often depressed for memory (73%), comprehension (49%), attention (46%), and constructional ability (44%). The greatest change was in total score in the > 60 microemboli group (-3.3 +/- 0.6) compared with -1.1 +/- 0.2 and -1.9 +/- 0.2 for the 30 to 59 and < 30 groups, respectively. The incidences of cardiac and pulmonary complications and mortality were different between those patients with < 60 microemboli versus those with > 60 microemboli. Cardiac and pulmonary complications and mortality percentages were 4.7%, 3.7%, and 0.9%, respectively, for the < 60 microemboli group and 20%, 20%, and 15%, respectively, for the > 60 microemboli group. We concluded that transcranial Doppler ultrasonography is a useful technique to quantify and detect the source of microemboli during coronary artery bypass operations and may be useful in assessing new operative strategies, the quality of the perfusion, and potentially as an indicator for pharmacologic therapy in the operating room in patients with high microemboli counts.

Cardiopulmonary Bypass↗
PubMed1995

Increased middle cerebral artery flow velocity during the initial phase of cardiopulmonary bypass may cause neurological dysfunction.

One hundred twenty-seven patients undergoing coronary artery bypass graft surgery were monitored by transcranial Doppler ultrasonography. Five patients had more than 50% increases in middle cerebral artery mean flow velocity during the initial phase (10-120 sec) of cardiopulmonary bypass. Four of these 5 developed neurological complications including stroke and encephalopathy. These results indicate that overperfusion of the basal cerebral arteries during cardiopulmonary bypass procedures may contribute to neurological dysfunction after the surgery.

Adult↗
PubMed1995

Interrater reliability of an etiologic classification of ischemic stroke.

BACKGROUND AND PURPOSE: Precise identification of the cause of stroke is critical to research and clinical practice. Published series of ischemic stroke show considerable variation in the proportion of cases classified as atherosclerotic large-vessel disease, lacunar infarct, cardioembolic stroke, stroke of other known cause, and stroke of undetermined etiology. We describe the development and use of an etiology-specific classification of ischemic stroke. The interrater reliability of the classification is then evaluated. METHODS: A total of 160 cases of ischemic strokes in young adults were reviewed by paired neurologists who assigned cases to prioritized categories. The results of paired ratings were evaluated for each of the potential causes. Interrater agreement was assessed by means of kappa, which is the chance-adjusted percent agreement. RESULTS: For standard pairs, kappa was fair to good for all causes except lacunar stroke (kappa = 0.31); however, pair-to-pair variation was greatest for lacunar strokes. Strokes of undetermined cause and hematologic/other cause were of borderline fair reliability. CONCLUSIONS: The utility of a stroke classification system is dependent on its intended use. An etiologic classification is useful in studies of the epidemiology and pathophysiological basis of stroke. Fair to good reliability for an etiologic classification of stroke can be obtained when criteria are explicit.

Adolescent↗
PubMed1995

Clinical features and pathogenesis of intracerebral hemorrhage after rt-PA and heparin therapy for acute myocardial infarction: the Thrombolysis in Myocardial Infarction (TIMI) II Pilot and Randomized Clinical Trial combined experience.

Parenchymatous intracerebral hemorrhage (ICH) is a serious, infrequent complication of thrombolytic therapy for acute myocardial infarction. We studied the clinical and radiologic features, manner of presentation, associated factors, and temporal course in 23 patients with ICH associated with 150 mg or 100 mg recombinant tissue-type plasminogen activator (rt-PA) and heparin therapy for acute myocardial infarction in the Thrombolysis in Myocardial Infarction (TIMI) II Pilot and Randomized Clinical Trial. In TIMI II, 13 of the 23 ICH patients developed or maintained systolic blood pressure > or = 160 mm Hg or diastolic blood pressure > or = 90 mm Hg during the rt-PA infusion and before the onset of neurologic symptoms. Six patients (26%) had life-threatening ventricular arrhythmias, five before onset of neurologic symptoms. A decreased level of consciousness was the earliest neurologic abnormality in 15 (65%) and the most common initial physical finding (in 19, or 82%). Onset was usually gradual (70%), but time to maximal deficit was frequently (61%) within 6 hours of onset. The locations of the primary ICH sites were lobar in 16 (70%), thalamic in four (17%), and brainstem-cerebellum in three (13%), but the putamen was never the primary site. Multiple lobar hemorrhages occurred in six cases (26%). The timing and size of ICH was similar among patients treated with 150 mg rt-PA and 100 mg rt-PA. Brain CT demonstrated an arteriovenous malformation in one case. Four patients had hypofibrinogenemia, which was profound in three patients. Pathologic findings were available for five patients. Of these, three patients had cerebral amyloid angiopathy, and one had hemorrhagic transformation of an ischemic cerebral infarction found at autopsy. We conclude that ICH following rt-PA and heparin therapy for acute myocardial infarction presents as a distinctive clinical syndrome. Intracerebral bleeding after combined thrombolytic and antithrombotic therapy may be associated with cerebral amyloid angiopathy and other vascular lesions. Acute or persistent hypertension before or during rt-PA infusion, life-threatening ventricular arrhythmias, and hypofibrinogenemia, either alone or in combination, may play roles in some cases. Care should be exercised when considering thrombolytic therapy for patients with risk factors for ICH.

Adult↗
PubMed1994

Gender and aphasia in the Stroke Data Bank.

Aphasia was present in 19.4% of the men and 22.5% of the women in the Stroke Data Bank. There were no gender differences in aphasia incidence among the intracerebral hemorrhages. Aphasia was more frequent among women with infarcts (37.0%) than men (28.3%). When stroke mechanism was controlled for, there was an excess of aphasia among the women with stroke due to cardiac embolism. When stroke site was controlled for, there were no gender differences in aphasia frequency. Wernicke's, global, and anomic aphasias were more common in women than men; Broca's aphasia was somewhat more common in men. Although there were no gender differences in infarct size overall, men with aphasia had larger infarcts than women with aphasia. Although gender differences were small, the infarct lesions producing aphasia in men were more posteriorly placed and the infarct lesions in women were more anteriorly placed, suggesting possible gender differences in the positioning of the language zone in the brain.

Aged↗
PubMed1992

Thalamic stroke. Presentation and prognosis of infarcts and hemorrhages.

Thalamic strokes in 62 patients selected from the Stroke Data Bank were studied to determine differences among 18 infarctions (INF), 23 localized hemorrhages (ICH), and 21 hematomas with ventricular extension (IVH). Stupor or coma at onset occurred more frequently in the IVH (62%) than in the INF (6%) or ICH (13%) groups and was reflected in significantly lower median Glasgow Coma Scores in the IVH group (7) than in the INF (15) and ICH (14) groups. Although ocular movements were more frequently abnormal in the IVH group compared with the ICH and INF groups, no significant differences were found in the frequency of motor or sensory deficits. Among the 62 strokes, 32 had restricted lesions of the posterolateral (n = 9), anterior (n = 3), paramedian (n = 7), and dorsal (n = 13) portions of the thalamus. Differences in consciousness and in motor, sensory, and oculomotor deficits were found among the topographic subgroups. Stroke-related deaths occurred in 52% of IVH cases, 13% of ICH cases, and no cases of INF. Median lesion volume as detected with computed tomography was greater in hemorrhages (INF, 2 cm3; ICH, 10 cm3; IVH, 16 cm3), with mortality related to increasing hematoma size. Coma, Glasgow Coma Score lower than 9, weakness score greater than 15 of a possible 30, abnormal ocular movements, and fixed pupils were also associated with stroke-related mortality. We conclude that the initial neurologic syndrome does not discriminate infarcts from intrathalamic hemorrhages. Ventricular extension, however, causes significantly more severe deficits and higher mortality.

Cerebral Hemorrhage↗
PubMed1992

Circadian rhythmicity of stroke onset. Intracerebral and subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: Our purpose was to describe and further understand the determinants of the time of onset of parenchymatous intracerebral hemorrhage and subarachnoid hemorrhage in patients enrolled in the Stroke Data Bank. METHODS: We analyzed the observed times of onset of intracerebral hemorrhage (n = 237 patients) and subarachnoid hemorrhage (n = 243 patients) compared with expected times of onset if the probability of onset was constant across all time intervals. We also analyzed the role of clinical features (if any) in explaining the findings. RESULTS: For intracerebral hemorrhage, 52.5% of patients reported onset times between 0600 hours and 1400 hours, with peak onset between 1000 and 1200 hours (chi 2 = 62.94, df = 11, p less than 0.001). Patients with subarachnoid hemorrhage were more likely to lack a history of hypertension compared with patients who had intracerebral hemorrhage (chi 2 = 23.3, df = 1, p less than 0.001). Patients with subarachnoid hemorrhage were more likely to have more uniform onset time throughout the day (chi 2 = 12.92, df = 7, p = 0.074). However, subarachnoid hemorrhage patients with a history of hypertension were more likely to have peak onset times in mid-to-late morning compared with patients without such a history (chi 2 = 35.25, df = 10, p less than 0.001). The nonuniformity of onset times for intracerebral hemorrhage persisted even if patients with unknown onset times were treated as through their onset times were randomly distributed between 0000 and 0800 hours. Seasonal periodicity and the relation between initial systolic or diastolic blood pressure and time of onset for either type of hemorrhage were not observed. CONCLUSIONS: Our data suggest that the time of onset for both intracerebral hemorrhage and subarachnoid hemorrhage patients with a history of hypertension is similar to the diurnal variation in blood pressure.

Adolescent↗
PubMed1992

Anosognosia in patients with cerebrovascular lesions. A study of causative factors.

BACKGROUND AND PURPOSE: Psychological and biological hypotheses have been proposed to explain anosognosia. We correlated the presence of anosognosia with the presence and severity of psychiatric disturbances, neglect, intellectual impairments, and computed tomographic evidence of lesion size, location, and measurements of brain atrophy. METHODS: A series of 80 patients with acute stroke were assessed using a battery of psychiatric and neuropsychological tests and computed tomography. RESULTS: There were five main findings. First, 27 (28%) of the 96 patients originally screened showed anosognosia. Second, patients with anosognosia had significantly higher frequencies of hemispatial neglect and related phenomena, as well as deficits in recognizing facial emotions and in receptive prosody. Third, depression was equally frequent among patients with and without anosognosia. Fourth, patients with anosognosia had a significantly higher frequency of right hemisphere lesions, primarily involving the temporoparietal junction, thalamus, and basal ganglia. Fifth, patients with anosognosia showed significantly more subcortical brain atrophy, primarily involving the frontal white matter and diencephalic areas. CONCLUSIONS: The present study demonstrates that anosognosia does not "protect" stroke patients from depressive feelings; rather, it represents arousal-attentional disorders after lesions in specific areas of the right hemisphere in nonaphasic patients with preexisting subcortical atrophy.

Aged↗
PubMed1992

Features on initial computed tomography scan of infarcts with a cardiac source of embolism in the NINDS Stroke Data Bank.

BACKGROUND AND PURPOSE: The lack of valid criteria for the clinical diagnosis of cardiogenic embolism is a major problem in both patient care and research. The aim of this study was to identify features on the initial computed tomogram of the brain that discriminate between patient groups with and without a cardiac source of embolism. To gain insight into the neuroradiological features relevant to the diagnosis of cardiac embolic stroke, we studied the initial computed tomogram of the 1,267 patients with ischemic stroke and such a scan in the National Institute of Neurological Disorders and Stroke (NINDS) Stroke Data Bank. METHODS: We analyzed the initial computed tomographic data from 1,267 patients with ischemic stroke in the NINDS Stroke Data Bank. Based solely on the presence of cardiac sources of embolism, we defined groups with high (n = 244), medium (n = 165), and low (n = 858) risk for cardiogenic embolism and compared the features on the initial computed tomogram among these three groups. RESULTS: Patients in the high-risk group were significantly more likely (p < 0.001) to have infarcts involving one half lobe or larger or infarcts involving both superficial and deep structures than patients in the medium- or low-risk groups. In contrast, deep small infarcts had a negative association (p = 0.004) with the presence of a cardiac source of embolism. There was no significant trend across risk groups in the percent with hemorrhagic infarction, regardless of whether patients with anticoagulant use at the time of the stroke were excluded. CONCLUSION: Although some features of the initial computed tomogram had highly significant associations with the presence of a cardiac source of embolism, the predictive value of these features for an embolic source was low.

Cerebral Infarction↗
PubMed1992

Distribution and correlates of sonographically detected carotid artery disease in the Cardiovascular Health Study. The CHS Collaborative Research Group.

BACKGROUND AND PURPOSE: This article describes the prevalence of extracranial carotid atherosclerosis assessed by ultrasonography, its association with risk factors, and its relation to symptomatic coronary disease and stroke in men and women aged > or = 65 years. METHODS: Maximum percent stenosis, maximum common carotid artery wall thickness, and maximum internal carotid artery wall thickness were assessed using duplex ultrasound in 5,201 men and women aged > or = 65 years in the Cardiovascular Health Study, a study of the risk factors and natural history of cardiovascular disease in the elderly. Existing coronary disease and stroke were assessed by physical examination and participant history. RESULTS: Detectable carotid stenosis was present in 75% of men and 62% of women, although the prevalence of > or = 50% stenosis was low, 7% in men and 5% in women. Maximum stenosis and maximum wall thickness measurements increased with age and were uniformly greater at all ages in men than in women (p < 0.00001). Established risk factors for atherosclerosis (hypertension, smoking, diabetes) and indications of vascular disease (left ventricular hypertrophy, major electrocardiographic abnormality, bruits, and history of heart disease or stroke) related to all three carotid artery measures in the elderly. Of the three ultrasound measures, the best correlate for a history of coronary disease was maximum internal carotid artery wall thickness. For stroke the best correlate was common carotid artery wall thickness. Multiple logistic regression models of prevalent coronary heart disease and stroke that included the ultrasound findings indicated, after adjustment for age and sex, that maximum internal wall thickness and maximum common carotid wall thickness were significant correlates of both. Maximum stenosis did not add significantly to the correlation. CONCLUSIONS: In the elderly the incidence of carotid atherosclerosis was high, although the frequency of severe disease was low. The prevalence and severity of carotid atherosclerosis continued to increase with age even in the late decades of life, and more disease was found in men than in women at all ages. Known risk factors for atherosclerosis continued to relate to carotid abnormalities in the later decades of life, both in symptomatic and asymptomatic subjects.

Aged↗
PubMed1992

Early clinical differentiation of cerebral infarction from severe atherosclerotic stenosis and cardioembolism.

BACKGROUND AND PURPOSE: Hyperacute cerebral infarction trials require early differentiation of infarction subtype. Our aim was to determine clinical factors predictive of infarction subtype from data collected in the early hours of admission. METHODS: Using the 1,273 patients enrolled in the Stroke Data Bank, stroke risk factors and demographic, clinical, and radiological features were compared between the 246 cardioembolic and 113 large-vessel atherosclerotic cerebral infarcts. RESULTS: Stroke Data Bank definitions ensured more transient ischemic attacks in atherosclerotic infarcts and more cardiac disease in cardioembolic infarcts, but the diagnosis was distinguished further using a logistic regression model. Fractional arm weakness (shoulder different from hand) (odds ratio 3.1, 95% confidence interval [CI] 1.6-5.8), hypertension (odds ratio 2.8, CI 1.4-5.3), diabetes (odds ratio 2.5, CI 1.2-5.1) and male gender (odds ratio = 2.2, CI 1.2-4.1) occurred more frequently in patients with atherosclerotic than cardioembolic infarcts. Reduced consciousness (odds ratio = 3.2, CI 1.4-7.3) was more frequent in cardioembolism. For a male patient with hypertension, diabetes, and fractional arm weakness, the estimated odds of an atherosclerotic infarction were 47-fold that of a cardioembolic infarction. Patients with atherosclerotic infarcts were more likely to have a fractional arm weakness regardless of infarct size, whereas, for those with cardioembolic infarctions, fractional weakness was more frequent in infarcts less than 20 cc in volume. CONCLUSIONS: Clinical features that are observed at stroke onset can help distinguish cerebral infarction subtypes and may allow for early stratification in therapeutic trials.

Aged↗
PubMed1992

Reduction of CSF monoamine metabolites in poststroke depression: a preliminary report.

Monoamine metabolites were measured in the cerebrospinal fluid (CSF) of depressed and nondepressed patients with acute stroke lesions and in nondepressed patients without stroke lesions. Depressed stroke patients had a significantly lower concentration of CSF 5-hydroxyindoleacetic acid (5-HIAA; a serotonin metabolite) than the other two groups. These findings suggest that poststroke depression may be mediated by serotonergic mechanisms.

Adult↗
PubMed1992

Infarcts with a cardiac source of embolism in the NINDS Stroke Data Bank: neurologic examination.

To gain insight into neurologic signs relevant to the diagnosis of cardiogenic embolism, we analyzed data from 1,290 patients with cerebral infarcts in the NINDS Stroke Data Bank. Based solely on the presence of potential cardiac sources of embolism, we divided patients into groups of high (N = 250), medium (N = 167), and low (N = 873) risk of a cardiogenic mechanism for their stroke. Diminished level of consciousness was highly associated with the presence of a cardiac source of embolism. Of the four primarily cortical deficits assessed, three (visual field abnormalities, neglect, and aphasia) showed a highly significant graded relationship to the cardiac risk groups. For the fourth cortical deficit (other nonlanguage cognitive functions), this relationship did not attain statistical significance. Conversely, hemiparesis without sensory or cortical deficits had a strong inverse association to the presence of a cardiac source of embolism. This inverse association was weaker for sensorimotor strokes and nonexistent for pure sensory strokes. Although some neurologic findings had highly significant associations with the presence of a cardiac source of embolism, their predictive value for an embolic source was low.

Cerebral Infarction↗
PubMed1991

Intracerebral hemorrhage: external validation and extension of a model for prediction of 30-day survival.

We report validation of a previously reported logistic regression model for predicting 30-day survival after supratentorial intracerebral hemorrhage using independent, prospectively collected data. The original model, using initial Glasgow Coma Scale score, hemorrhage size, and pulse pressure, accounted for mortality or survival at 30 days in 92% of patients in the Pilot Stroke Data Bank with a sensitivity of 0.84 and a specificity of 0.96. For external validation, the model was used to predict 30-day status for each patient in the Main Phase Stroke Data Bank for whom complete risk factor information was available. Overall, 90% of patients' outcomes were correctly predicted with a sensitivity of 0.85 and a specificity of 0.92. Two factors not collected in the Pilot Stroke Data Bank, hyperglycemia and intraventricular hemorrhage extension, were assessed to determine if they provided additional predictive information on 30-day mortality. Intraventricular hemorrhage extension contributed significant predictive information in a logistic regression, whereas hyperglycemia did not. The resulting four-factor model with an interaction term (intraventricular hemorrhage extension and Glasgow Coma Scale score) correctly classified the survival status of 94% of patients at 30 days. A more general outcome, death or failure to achieve a "good" Activities of Daily Living Score by one year, was analyzed with respect to the same four factors. The resulting model correctly classified 95% of the patients in the cohort.

Blood Glucose↗
PubMed1991

Transcortical aphasia. Importance of the nonspeech dominant hemisphere in language repetition.

While a relative preservation of repetition in acute transcortical aphasia (TA) has usually been associated with the functional integrity of the speech dominant (left) perisylvian area, recent amytal data (Bando et al., 1986) have suggested a fundamental role of the nondominant (right) hemisphere in language repetition. The neuroradiological correlates of repetition were studied in a consecutive series of 21 patients with acute TA. A similar frequency of either perisylvian or extraperisylvian pathology was found. In 2 patients with perisylvian pathology, the injection of amytal in the hemisphere contralateral to the lesion abolished repetition. Positron emission tomography (PET) in another patient revealed marked hypometabolism over the entire left cortical mantle ipsilateral to a basal ganglia lesion, suggesting that preserved repetition was carried out by right hemisphere structures. This was confirmed in a second patient with left extraperisylvian pathology, in whom a second lesion in the right hemisphere resulted in impaired repetition. These findings suggest that the spared contralateral hemisphere may subserve residual repetition in some transcortical aphasic patients with a lesion within or outside the speech-dominant perisylvian area.

Aged↗