Magnetic resonance angiography in patients with brain infarction.

This study evaluated the role of magnetic resonance angiography (MRA) in detecting extra- or intracranial vascular disease in 118 patients with brain infarction and the accuracy of MRA diagnosis when compared with conventional angiography in patients who had both investigations. Magnetic resonance angiography ruled out extra- and intracranial large vessel disease in 36% of the patients. MRA also demonstrated extra- or intracranial disease in 56% (probably symptomatic in 31, possibly symptomatic in 18, and asymptomatic in 17 patients), and provided no information in 8% of the 118 patients. Among the 176 major vessels visualized by both MRA and conventional angiography, conventional angiography confirmed the presence of 9/10 extracranial and 32/40 intracranial large vessel abnormalities detected on MRA. There were two false-negative findings on MRA: occlusion of a distal branch of middle cerebral artery, and an asymptomatic posterior cerebral artery stenosis. Magnetic resonance angiography is a clinically useful method for screening extra- and intracranial disease in patients with brain infarction and selecting high-yield patients for conventional angiography.

Intracerebral hemorrhage in blacks. Risk factors, subtypes, and outcome.

BACKGROUND AND PURPOSE: Blacks are at a higher risk for intracerebral hemorrhage (ICH) than whites; however, few data are available regarding the demographic and clinical characteristics of ICH among blacks. METHODS: We determined the frequency of risk factors, etiologic subtypes, and outcome among consecutive black patients admitted with nontraumatic ICH to a university-affiliated public hospital. RESULTS: The most common risk factors in the 403 black patients with ICH were preexisting hypertension (77%), alcohol use (40%), and smoking (30%). Among the 91 nonhypertensive patients, 21 (23%) were diagnosed with hypertension after onset. Compared with women, men had a younger age of onset (54 versus 60 years; P < .001) and higher frequency of alcohol use (54% versus 22%; P < .001) and smoking (39% versus 17%; P < .001). ICH secondary to hypertension (n = 311) and of undetermined etiology (n = 73) were the most common subtypes in blacks. Patients aged 65 years and older (compared with those aged 15 to 44 years; P = .001) and women (compared with men; P = .02) were more likely to be dependent at discharge. CONCLUSIONS: Primary preventive strategies are required to reduce the high frequency of modifiable risk factors predisposing to ICH in blacks.

Cerebral hemodynamics in preeclampsia and eclampsia.

OBJECTIVE: To test further the hypothesis that preeclampsia and eclampsia are associated with cerebral vasospasm. DESIGN: Prospective case study. SETTING: Inpatient obstetrics service of an urban public hospital. PATIENTS AND METHODS: Eleven women with eclampsia (mean gestational age, 32 weeks), preeclampsia (mean gestational age, 36 weeks), or normotensive pregnancy (mean gestational age, 35 weeks). Middle cerebral artery (MCA) velocity was measured bilaterally in all patients by means of transcranial Doppler ultrasonography. RESULTS: Eclamptic patients (n = 3) had significantly higher mean flow velocities and lower average pulsatility indexes than did normotensive patients (n = 4) (average MCA-mean flow velocity, 165 vs 79 cm/s [P = .007]; average MCA pulsatility index, 0.51 vs 1.1 [P < .001]). Compared with normotensive pregnant women, preeclamptic patients (n = 4) had lower average pulsatility indexes (0.76, P = .003), but similar mean flow velocities (average MCA-mean flow velocity, 82 cm/s; P = .8). CONCLUSION: Significantly higher MCA velocities in eclamptic, but not preeclamptic, women compared with those in normotensive pregnant women suggests that moderate to severe vasospasm is associated with eclampsia.

Loss of autoregulation in patients with intracerebral hemorrhage.

We evaluated cerebral vasomotor reactivity to acetazolamide in seven consecutive patients with intracerebral hemorrhage (ICH) with transcranial Doppler to evaluate autoregulation of cerebral blood flow in acute ICH. Two patients had prominent loss of vasoreactivity to acetazolamide stimulation. This suggests that autoregulation may be impaired in some patients with acute ICH. Further studies are required to determine the clinical implications of loss of autoregulation in acute phase of ICH.