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The authors report a patient with postpartum intracerebral hemorrhage associated with cerebral vasculitis. Cerebral circulation was assessed with transcranial Doppler (TCD) ultrasonography, magnetic resonance angiography, and conventional cerebral angiography. Initial TCD studies demonstrated bilateral patchy increased cerebral blood flow velocity (CBFV) in the anterior circulation with complete normalization during remission. This case report provides evidence that cerebral vasculitis leads to relevant CBFV changes and that the TCD technique may assist in diagnosis and follow-up of these patients. [ABSTRACT FROM AUTHOR]

Describes the case of a patient who had extensive brain calcification after ischemic stroke. Result of the brain computed tomographic scan; Organs which are common sites of visceral calcification.

Background and Purpose: Crossed cerebellar diaschisis (CCD), the decrease in blood flow and metabolism in the cerebellar hemisphere contralateral to a supratentorial stroke, is frequently reported on positron-emission tomography (PET) and single-photon emission CT (SPECT) but is rarely described with MR perfusion techniques. This study was undertaken to determine the frequency of CCD observed in acute stroke by retrospective review of a research data base of patients with acute stroke evaluated by diffusion-weighted (DWI) and dynamic contrast susceptibility perfusion MR imaging (PWI)., Materials and Methods: PWI scans of 301 consecutive patients with acute stroke and positive DWI abnormality from a research data base were reviewed. Contralateral cerebellar hypoperfusion was identified by inspection of time-to-peak (TTP) maps for asymmetry with an absence of cerebellar abnormalities on T2-weighted scans, DWI, or disease of the vertebrobasilar system on MR angiography. In a subset of the cases, quantitative analysis of perfusion scans was performed using an arterial input function and singular value decomposition (SVD) to generate cerebral blood flow (CBF) maps., Results: A total of 47 of 301 cases (15.61%) met the criteria of CCD by asymmetry of cerebellar perfusion on TTP maps. On quantitative analysis, there was corresponding reduction of CBF by 22.75 +/- 10.94% (range, 7.45% to 52.13%) of the unaffected cerebellar hemisphere)., Conclusions: MR perfusion techniques can be used to detect CCD, though the frequency presented in this series is lower than that commonly reported in the PET/SPECT literature. Nevertheless, with its role in acute stroke and noninvasive nature, MR perfusion may be a viable alternative to PET or SPECT to study the phenomenon and clinical consequences of supratentorial stroke with CCD.

We report a series of six single subject studies examining the effects of pharmacological blood pressure elevation on regional brain perfusion and language function. Previous reports indicate that hypoperfusion of specific brain regions, as delineated by magnetic resonance perfusion weighted imaging (PWI), is associated with disruption of selective lexical functions. On this basis, we hypothesized that reperfusion of the same regions, in the absence of infarct in that region, would restore the associated lexical function. We present five patients with impaired lexical-semantics associated with poor perfusion, but not infarction, of Brodmann's area 22 (BA 22), and one patient with impaired lexical-semantics and a superimposed deficit in retrieving the phonological representations of words, associated with poor perfusion Brodmann's area 37 (BA 37) as well as BA 22. Each patient was treated with induced blood pressure elevation to increase perfusion of the ischemic and dysfunctional tissue. Daily testing of naming and comprehension, with stimulus sets matched for frequency, familiarity, and length, showed improved lexical-semantics in the patients who showed reperfusion of BA 22 and improved oral naming (but not lexical-semantics) in the patient who showed reperfusion of BA 37. These cases illustrate that loss of function with hypoperfusion of a circumscribed area of the brain, and recovery of the same function with improved perfusion of that brain region, can reveal brain/language relationships prior to reorganization after brain injury., (Copyright 2001 Elsevier Science.)

Background: Stroke remains a devastating complication of cardiac surgery, but stroke prevention remains elusive. Evaluation of early and long-term clinical outcomes and brain-imaging findings may provide insight into stroke prognosis, etiology, and prevention., Methods: Five thousand nine hundred seventy-one cardiac surgery patients were prospectively studied for clinical evidence of stroke. Stroke and nonstroke patients were compared by early outcomes. Data collected for stroke patients included brain imaging results, long-term functional status, and survival. Outcome predictors were then determined., Results: Stroke was diagnosed in 214 (3.6%) patients. Brain imaging demonstrated acute infarction in 72%; embolic in 83%, and watershed in 24%. Survival for stroke patients was 67% at 1 year and 47% at 5 years. Independent predictors of survival were cerebral infarct type, creatinine elevation, cardiopulmonary bypass time, preoperative intensive care days, postoperative awakening time, and postoperative intensive care days. Long-term disability was moderate to severe in 69%., Conclusions: Stroke after cardiac surgery has profound repercussions that are independently related to infarct type and clinical factors. These data are essential for clinical decision making and prognosis determination.

This article presents the case of a healthy 46-year-old man who experienced a dissection of the internal carotid artery. The diagnosis of this condition is not usually clear-cut, especially in a young patient with unremarkable medical history, and because of the similarity of symptoms with migraine. Often there is no obvious cause of a cerebral artery dissection, although subtle abnormalities of connective tissue may be present. Anticoagulation is generally used for therapy, but clinical trials are lacking. Carotid artery dissection should be considered as a cause of stroke in young healthy adults.

Background: Neurologic complications after cardiac surgery include stroke, encephalopathy, and persistent cognitive impairments. More precise neuroimaging of patients with these complications may lead to a better understanding of the etiology and treatment of these disorders., Objective: To study the pattern of ischemic changes on diffusion- and perfusion-weighted magnetic resonance imaging (DWI, and MRPI, respectively) in patients with neurologic complications after cardiac surgery., Methods: All records were reviewed of our patients undergoing cardiac surgery in the previous year who also underwent postoperative DWI or MRPI. Neurologic symptoms, vascular studies, and the pattern of ischemic changes were recorded. Acute ischemic lesions were classified as having a territorial, watershed, or lacunar pattern of infarction. Patients with multiple territorial infarcts in differing vascular distributions that were not explained by occlusive vascular lesions were classified as having multiple emboli., Results: Fourteen patients underwent DWI and 4 underwent MRPI. Acute infarcts were found in 10 of 14 patients by DWI as compared with 5 of 12 patients by computed tomography. Eight patients presented with encephalopathy (associated with focal neurologic deficits in 4), 4 with focal deficits alone, and 2 with either fluctuating symptoms or transient ischemic attacks. Among patients with encephalopathy, 7 of 8 had patterns of infarction suggestive of multiple emboli, including 3 of 4 patients with no focal neurologic deficits. Several patients had combined watershed and multiple embolic patterns of ischemia. Findings of MRPI studies were abnormal in 2 of 4 patients, showing diffusion-perfusion mismatch; both patients had either fluctuating deficits or transient ischemic attacks, and their conditions improved with blood pressure manipulation., Conclusions: In patients with neurologic symptoms after cardiac surgery, DWI is more sensitive to ischemic change than computed tomographic scanning and can demonstrate patterns of infarction that may help us understand etiology. The most common pattern was multiple embolic infarcts. Preliminary experience with MRPI suggests that some patients have persistent diffusion-perfusion mismatch after surgery and may benefit from therapeutic intervention.

Objective: The impact of early transcranial Doppler ultrasonography (TCD) upon stroke subtype diagnosis is unknown and may affect therapeutic strategies. In this study, the diagnostic usefulness of TCD in stroke subtype diagnosis according to the criteria of the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) study was investigated in patients with acute cerebral ischemia., Methods: TCD examination within 24 h of symptom onset was performed in 50 consecutive patients with acute cerebral ischemia. Of these 54% were female. Sixty percent of patients were black, 36% white, and 4% Asian. Initial TOAST stroke subtype diagnosis (ITSSD) was based upon clinical presentation and initial brain imaging studies. Modified TOAST stroke subtype diagnosis was determined subsequently after additional review of the TCD examination. Final TOAST stroke subtype diagnosis was determined at hospital discharge, incorporating all diagnostic studies. Using final TOAST stroke subtype diagnosis as the 'gold standard' ITSSD and modified TOAST stroke subtype diagnosis were compared in order to determine additional benefit from the information obtained by TCD. Data were collected retrospectively by a single investigator., Results: ITSSD classified 23 of 50 (46%) patients correctly. After TCD, 30 of 50 (60%) patients were classified correctly, for an absolute benefit of 14% and a relative benefit of 30% (p = 0.018). Most benefit from TCD was observed in the TOAST stroke subtype category large-artery atherosclerosis, in particular in patients with intracranial vascular disease. In this category, ITSSD had a sensitivity of 27% which increased to 64% after TCD (p = 0.002)., Conclusion: TCD within 24 h of symptom onset improves the accuracy of early stroke subtype diagnosis in patients with acute cerebral ischemia due to large-artery atherosclerosis. This may have clinical implications for early therapeutic interventions., (Copyright 2001 S. Karger AG, Basel.)

We report a 37-year-old woman with Marfan syndrome (MFS) who presented with acute myelopathy secondary to a subdural spinal hematoma. The patient died of a subarachnoid hemorrhage 4 days later. Autopsy showed a markedly ectatic vertebrobasilar system with fragmentation of the internal elastic lamina. Microscopic examination of the aorta similarly showed a fragmented internal elastic lamina. We discuss the implications of our patient's early onset vertebrobasilar dolichoectasia; this intracranial disease represents a rare cause of subarachnoid hemorrhage in MFS., (Copyright © 2000 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Diagnostic testing in patients with ischemic stroke serves many purposes, including confirmation of the diagnosis and providing clues as to possible causes. Evaluation of the cerebral vasculature, the heart, the blood coagulation system, and selected other diagnostic tests may point to a mechanism of stroke which helps determine treatment and prognosis. With the recent advent of acute interventions for ischemic stroke, diagnostic testing is now an important component in the emergency management of stroke. In this article, the authors will review the standard approach to diagnostic testing for patients with ischemic stroke or transient ischemic attack, and new developments in neuro-imaging and their use in acute stroke assessment.

Diffusion-weighted MR imaging is generally thought to be highly sensitive for the diagnosis of acute stroke. We report two cases of hyperacute stroke with absence of changes on diffusion-weighted images within 4 hours of symptom onset. Follow-up studies, performed 4 days later, showed infarction in regions compatible with the clinical presentation and (in one case) with the initial perfusion deficit. These cases indicate that normal findings on diffusion-weighted images in patients with suspected cerebral ischemia do not rule out impending infarction.

Acquired dysfunction of the sense of smell and taste is usually associated with orbitofrontal tumors or trauma and is rarely reported to have occurred after ischemic stroke. We report on a patient who noted impairment of the sense of smell and taste after a localized insular frontoparietal stroke and who also had a similar, mirror-image infarction in the other hemisphere. Injury to an area of the cortex responsible for the integration of taste and smell may have accounted for this patient's symptoms.

Purpose: To determine the distribution and correlates of elevated total homocyst(e)ine (tHcy) concentration in a population of premenopausal black and white women., Methods: Data from the Stroke Prevention in Young Women Study (N = 304), a population-based study of risk factors for stroke in women aged 15-44 years of age, were used to determine the distribution and correlates of elevated tHcy in black (N = 103) and white women (N = 201)., Results: The mean tHcy level for the population was 6.58 micromol/L (range 2.89-26.5 micromol/L). Mean tHcy levels increased with age, cholesterol level, alcohol intake, and number of cigarettes smoked (all: p < 0.05). There were no race differences (mean tHcy 6.72 micromol/L among blacks and 6.51 micromol/L among whites; p = 0.4346). Regular use of multivitamins and increasing education was associated with significant reductions in tHcy concentration. Approximately 13% of the sample had elevated tHcy levels, defined as a tHcy concentration > or = 10.0 micromol/L. Multivariate-adjusted correlates of elevated tHcy included education > 12 vs. < or = 12 (odds ratio [OR] = 0.4, 95% confidence interval [CI] = 0.2-0.8); smoking > or = 20 cigarettes/day vs. nonsmokers (OR = 2.8, 95% CI = 1.1-7.3); and the regular use of multivitamins (OR = 0.4, 95% CI = 0.2-0.9)., Conclusions: These results suggest that a substantial proportion of healthy young premenopausal women have tHcy levels that increase their risk for vascular disease. A number of potentially modifiable behavioral and environmental factors appear to be significantly related to elevated tHcy levels in young women.

Purpose: To describe the electrographic and clinical features of nonconvulsive status epilepticus (NCSE) in the critically ill elderly and to identify potential predictors of outcome., Methods: We prospectively identified 25 episodes of altered mentation and NCSE in 24 critically ill elderly patients associated with generalized, focal, or bihemispheric epileptiform EEG patterns. Patients with anoxic encephalopathy were excluded., Results: Of 25 hospitalizations, 13 (52%) resulted in death, and 12 (48%) patients survived to discharge. Death was associated with the number of acute, life-threatening medical problems on presentation (survivors, 1.8; fatalities, 2.8; p = 0.013) and with generalized EEG pattern (p = 0.017). Higher doses or greater number of antiepileptic drugs (AEDs) did not improve outcome. Treatment with intravenous benzodiazepines was associated with increased risk of death (p = 0.033). Ten patients with advance directives were managed outside the intensive care unit (ICU). Mean hospitalization was 39 days in the ICU group and 22 for those with advance directives (p = 0.017)., Conclusions: Severity of illness correlates with mortality in critically ill elderly patients with NCSE. Treatment with intravenous benzodiazepines may increase their risk of death. Aggressive ICU management may prolong hospitalization at considerable cost, without improving outcome. It is unclear whether NCSE affects outcome in the critically ill elderly or is merely a marker for severity of disease in predisposed patients. The benefits of aggressive therapy are unclear. Carefully controlled, prospective trials will be necessary to determine the best therapies for NCSE in the critically ill elderly and the appropriate role of the ICU in their management.

Objective: To describe the clinical features of patients with occlusive disease of the proximal (V1) segment of the vertebral artery., Design and Patients: Patients with either occlusion or high-grade stenosis involving the V1 segment were chosen for study from the New England Medical Center Posterior Circulation Registry. The registry is a consecutive series of patients with signs and symptoms of posterior circulation ischemia seen at the New England Medical Center, Boston, Mass, during a 10-year period. Clinical features, radiographic findings, and patient outcome were reviewed., Results: Of the 407 patients in the registry, 80 (20%) had V1 segment lesions. Patients could be classified into 5 groups: (1) V1 disease and coexistent severe intracranial occlusive disease of the posterior circulation (n=22); (2) V1 disease with evidence of artery-to-artery embolism (n=19); (3) suspected V1 disease with artery-to-artery embolism, but with other potential causes of stroke or less certain vascular diagnosis (n=20); (4) V1 disease associated with hemodynamic transient ischemic attacks (n=13); and (5) proximal vertebral arterial dissection (n=6). Hypertension, cigarette smoking, and coronary artery disease were common risk factors. Clinical features, location of infarct, and outcome differed between groups and reflected the presumed mechanisms of stroke., Conclusions: Occlusive disease involving the V1 segment of the vertebral artery is common in patients with posterior circulation ischemia, but is often associated with other potential mechanisms of stroke. However, in a series of patients seen at a tertiary referral center, occlusive disease of the V1 segment was the primary mechanism of ischemia in 9% of patients.

A polymorphism associated with a thermolabile variant (C677T) of the enzyme methylenetetrahydrofolate reductase has been associated with both elevated total homocysteine (tHcy) levels and risk for cardiovascular disease. Data from the Stroke Prevention in Young Women Study were used to determine the prevalence of the C677T genotype and to assess whether environmental factors modified the association between genotype and tHcy concentration. The C677T genotype prevalence was 80% -/-, 20% +/-, and 0% +/+ among 46 African-American women; and 39% -/-, 53% +/-, and 8% +/+ among 77 white women (P < 0.01). There was a trend toward higher tHcy levels in African-American women with the +/- genotype when compared with the -/- genotype (6.9 mumol/L vs 5.3 mumol/L respectively, p = 0.10); no association was found among the white women (6.0 mumol/L, -/-; 4.5 mumol/L, +/-; and 6.2 mumol/L, +/+; p = 0.67). Among African American women, those who smoked and were +/- genotype had the highest tHcy levels (8.0 mumol/L); while among white women, those who smoked and were -/- had the highest tHcy levels (8.1 mumol/L). Despite being hampered by a limited sample size, the thermolabile allele is significantly less common among African-American than white women. The association between genotype and tHcy concentration is influenced by smoking and multivitamin use.

Background: It is widely believed that pregnancy increases the risk of stroke, but there are few data available to quantify that risk., Methods: We identified all female patients 15 through 44 years of age in central Maryland and Washington, D.C., who were discharged from any of 46 hospitals in the study area in 1988 or 1991. Two neurologists reviewed each case, using data from the women's medical records. We determined whether the women had been pregnant at the time of the stroke or up to six weeks before it occurred. For purposes of this analysis, the six-week period after pregnancy could begin with an induced or spontaneous abortion or with the delivery of a live or stillborn child., Results: Seventeen cerebral infarctions and 14 intracerebral hemorrhages occurred in women who were or had recently been pregnant (pregnancy-related strokes), and there were 175 cerebral infarctions and 48 intracerebral hemorrhages that were not related to pregnancy. For cerebral infarction, the relative risk during pregnancy, adjusted age and race, was 0.7 (95 percent confidence interval, 0.3 to 1.6), but it increased to 8.7 for the postpartum period (after a live birth or stillbirth) (95 percent confidence interval, 4.6 to 16.7). For intracerebral hemorrhage, the adjusted relative risk was 2.5 during pregnancy (95 percent confidence interval, 1.0 to 6.4) but 28.3 for the postpartum period (95 percent confidence interval, 13.0 to 61.4). Overall, for either type of stroke during or within six weeks after pregnancy, the adjusted relative risk was 2.4 (95 percent confidence interval, 1.6 to 3.6), and the attributable, or excess, risk was 8.1 strokes per 100,000 pregnancies (95 percent confidence interval, 6.4 to 9.7)., Conclusions: The risks of both cerebral infarction and intracerebral hemorrhage are increased in the six weeks after delivery but not during pregnancy itself.

Dural arteriovenous fistula is an uncommon cause of myelopathy. The nidus of the malformation is on or within the dura and results in a mass of serpentine vessels on the dorsal surface of the spinal cord, usually at low thoracic or lumbar levels. Onset is usually between ages 40 and 70 years. Male to female ratio is 4:1. Symptoms include pain, progressive proximal weakness of lower limbs, saddle area numbness, claudication, and difficulty with urination. Course may be fluctuating or slowly progressive. Signs include upper and lower motor neuron abnormalities and nondermatomal sensory loss. Spinal bruit is rare. Magnetic resonance imaging may show an enlarged cord or abnormalities on its dorsal surface. Myelography (patient prone and supine) is the procedure of choice. Motor neuron disease, disc disease, spinal cord tumor, and multiple sclerosis are differential considerations. Untreated patients have a poor prognosis. Excision of the nidus, ligation of the draining vein, and endovascular embolization may be helpful even in patients with severe deficits.

Objective: To review selected aspects of the current treatment of acute ischemic stroke and provide an overview of basic neuroscience research in cerebral ischemia that may be applicable to future therapies., Data Sources: Selected recent references dealing with current therapy of acute stroke and basic neuroscience developments in cerebrovascular disease from the past several years., Study Selection/data Extraction: Whenever possible, recommendations concerning treatment were based on results of clinical trials; when such data were lacking, the authors present possible treatment approaches., Data Synthesis: Acute stroke is a heterogeneous process involving different etiologic mechanisms. Different types of stroke, however, may produce a similar cascade of physiologic and biochemical events leading to tissue damage. Calcium flux, glutamate excitotoxicity, platelet and leukocyte activation, free radical formation, and nitric oxide metabolism may be crucial focal points of future stroke therapy., Conclusions: Recent clinical trials have given scientific basis for some of our treatment approaches to ischemic stroke. Future treatments for stroke will likely focus on factors which modulate biochemical events occurring as a final common pathway to all forms of cerebral ischemia.

Hypertension is the major risk factor for intracerebral hemorrhage (ICH) and is present in about 50% of patients with ICH. Common clinical findings are focal neurologic deficits at onset, gradually progressive deterioration, and the presence of headache, vomiting, and depressed level of consciousness. The clinical syndromes of ICH at common locations are reviewed. CT scanning has dramatically changed our thinking about ICH and allowed better correlation of neurologic findings with lesions at various sites.

The activity of Ca-ATPase (Ca2+,Mg2+-ATPase, ATP phosphohydrolase, EC 3.6.1.3) was measured in erythrocyte membrane preparations from 37 cystic fibrosis patients, 27 with pancreatic insufficiency and 10 with pancreatic sufficiency, and from 24 healthy controls. The mean maximal calcium-stimulated specific activities, in the absence and presence of purified calmodulin, of the pancreatic sufficient patients (34.3 +/- 4.2 and 75.9 +/- 6.9 nmol/min/mg) was indistinguishable from that of controls (35.8 +/- 2.6 and 84.3 +/- 4.7 nmol/min/mg), while both activities of patients with pancreatic insufficiency were significantly decreased (28.9 +/- 1.3, p less than 0.02; 65.2 +/- 3.0, p less than 0.001) compared to the control group. Similarly, the mean erythrocyte membrane (Na + K)ATPase activity was decreased only for those patients with a history of steatorrhea and who clinically required pancreatic enzyme therapy and had low immunoreactive trypsin levels (10.6 +/- 0.8 versus control, 13.4 +/- 1.1, and pancreatic sufficient patients, 13.3 +/- 1.4 nmol/min/mg; p less than 0.025). No correlation was found between any of the ATPase activities and the clinical scores of the patients, suggesting the lack of significant contribution of general clinical status to the activities of those cation transporters.

The tnpR gene product, resolvase, of the transposable element gamma delta mediates site-specific recombination between two copies of gamma delta directly repeated on the same replicon, and it negatively regulates transcription of the tnpA (transposase) gene and its own gene. The recombinational site, res, and the regulatory region both are located in the tnpA-tnpR intercistronic region. In studying the interaction of purified resolvase with DNA fragments derived from gamma delta and the related transposon, Tn3, that span this region, we have demonstrated that three sites specifically bind resolvase. Site I overlaps the recombinational crossover point and both transcriptional promoters. Sites II and III cover most of the DNA between the crossover point and the translational start of the tnpR gene. These are the only binding sites we have detected in a region of about 400 base pairs centered on the crossover point. Studies of cointegrates that contain only part of the region that binds resolvase indicate that site I is not sufficient for efficient site-specific recombination and suggest that all three sites are probably required.