Magnetic resonance angiography in patients with acute stroke treated by local thrombolysis

Although magnetic resonance angiography (MRA) is accepted for showing chronic intracranial stenotic or occlusive lesions, the method has not been practically examined in patients with acute cerebral ischaemia. We carried out three-dimensional time-of-flight MRA in six patients with acute ischaemia treated by local thrombolysis, and compared the findings with those of digital subtraction angiography (DSA). In all patients, MRA before thrombolysis clearly demonstrated the occluded arteries, which corresponded precisely to those shown by DSA. In four patients with complete recanalisation of the occluded vessels after thrombolysis, the recanalisation could be demonstrated by postoperative MRA. In one patient with reocclusion of the recanalised artery, repeat MRA also demonstrated the reocclusion, confirmed by DSA. These results suggest that MRA may be helpful for noninvasive investigation before and after thrombolysis.     

The development of hyperglycaemia in patients with insulin-resistant generalized lipoatrophic syndromes

Insulin resistance is present in patients suffering from lipoatrophic syndromes long before the onset of diabetes mellitus. Thus, the decreased peripheral glucose disposal may not be the only mechanism of hyperglycaemia. The kinetic parameters of glucose homeostasis were evaluated in six young females aged 15, 16, 18, 19 and 24 years with generalized lipoatrophy; one patient was studied both at 12 and 15 years. Insulin resistance was evaluated in vivo by the hyperinsulinaemic euglycaemic clamp (3-4 insulin infusion rates from 1 to 100 mU/kg.min). All patients showed a rightward shift of the dose-response curve, indicating decreased insulin sensitivity. In two patients, maximal glucose disposal was moderately decreased, while in five patients it was dramatically reduced (3.6-6.9 mg/kg.min). Fasting plasma glucose was variable (4.3-18.3 mmol/l) and did not correlate with peripheral glucose disposal rates. Hepatic glucose production, measured by infusion of [6,6-2H] glucose, varied from 1.7 to 8.3 mg/kg.min and was significantly correlated with fasting plasma glucose. The overproduction of glucose despite basal hyperinsulinism suggested hepatic insulin resistance, which was confirmed by the abnormal response to constant unlabelled glucose infusion (2 mg/kg.min) in five patients. In conclusion, impaired glucose tolerance seems to develop in generalized lipoatrophy with aggravated peripheral insulin resistance. The present data show that fasting hyperglycaemia is mainly the consequence of increased hepatic glucose production.     

Predictors of hemorrhagic transformation occurring spontaneously and on anticoagulants in patients with acute ischemic stroke

We describe a case of microscopic polyangiitis involving skin and joints after influenza vaccination. Titers of antiinfluenza A antibody were markedly elevated in synovial fluid (SF) relative to those in serum. Antiinfluenza B antibodies were not present in SF but were present in serum, suggesting a reaction specifically involving antiinfluenza A antibodies localized to the affected joint. A review identified 16 other cases of vasculitis after influenza vaccination. The cases reclassified according to the Chapel Hill diagnostic criteria identified multiple forms of vasculitis including 7 other cases of microscopic polyangiitis. Three patients had similar illnesses after previous influenza vaccination or influenza-like illness. As in our case 11 cases resolved without recurrence. While this does not provide conclusive evidence that the vaccination caused the vasculitis, together with the serologic data we present it supports this hypothesis.     

The scalability of the Rivermead Motor Assessment in acute stroke patients

OBJECTIVE: To examine the scalability of the Rivermead Motor Assessment with hospitalized acute stroke patients. DESIGN: This was a prospective study of hospitalized stroke patients. SUBJECTS: Fifty-one selected stroke patients, including those over the age of 65, were assessed at one, three and six weeks post-stroke using the Rivermead Motor Assessment. Coefficients of scalability and reproducibility were calculated for each of the three sections of the Rivermead Motor Assessment at each assessment. RESULTS: The items in the gross function and arm sections met scaling criteria at all three assessments which meant that they were in appropriate order of difficulty. There was an overall increase in the proportion of subjects passing each item at successive assessments, suggesting that patients in the study were recovering. The leg and trunk section did not meet scale criteria with these acute stroke patients. CONCLUSIONS: We recommend that only the gross function and arm sections should be used as hierarchical scales with selected acute stroke patients. The leg and trunk section should only be used as an assessment checklist.     

Task-specific physical therapy for optimization of gait recovery in acute stroke patients

A randomized controlled pilot trial was conducted to estimate the effects of early, intensive, gait-focused physical therapy on ambulatory ability in acute, stroke patients. Twenty-seven patients with middle cerebral artery infarct of thromboembolic origin confirmed by computed axial tomography scan were stratified and randomly assigned to the experimental group, to a control group that received early, intensive and conventional therapy, or to a group receiving routine conventional therapy that started later and was not intense. Assessments at entry, six weeks, and three and six months by independent evaluators permitted comparisons with reference to clinical measures of motor performance, balance, and functional capacity, and laboratory measures of gait movements. Group results at six weeks demonstrated that gait velocity was similar in the two conventional groups thereby eliminating the timing of the interventions as an important factor. At that point, gait velocity was faster in the experimental group. The difference translated into a moderate effect size of 0.58. The time dedicated to gait training but not to total therapy time was correlated (rs = 0.63) to gait velocity. This effect disappeared at three and six months after stroke. These pilot results justify planning a large trial to test the effectiveness of a therapeutic protocol that focuses on early and intense gait therapy in an effort to facilitate early ambulation following stroke.     

Can acute stroke be treated with hypothermia?

In animal stroke models, treatment with mild hypothermia (30-34 degrees C) for 3-4 hours may reduce the size of cerebral infarction if started within three hours of the initiation of cerebral ischaemia. The mechanism by which hypothermia exerts its neuroprotective effect is unknown, but experimental studies have shown the release of neurotoxic excitatory amino acids and free oxygen radicals to be reduced during hypothermic ischaemia. In patients with acute stroke, body temperature above 37.5 degrees C are associated with poor outcome, and temperatures below 36.5 degrees C with improved outcome, compared to normothermic patients. Due to the unpleasantness of cooling and side effects as shivering, hypothermia may not be tolerated by stroke patients without sedation of light anaesthesia which may increase the risk of hypotension and respiratory complications. However, lowering body temperature by 1-2 degrees C may suffice to improve functional outcome in acute stroke patients, and such mild hypothermia should be tested in randomized controlled clinical trials.     

Delayed hospitalization of the patient with acute stroke

INTRODUCTION AND OBJECTIVE: We analyze the main factors influencing the time delay between onset and admission to the hospital in acute stroke. PATIENTS AND METHODS: Consecutive series of 1,344 patients with acute stroke or transient ischemic attack admitted at two reference hospitals of Valencia and included at the same stroke register. Factors assessed were age, sex, vascular risk factors, stroke onset and arrival at hospital, stroke severity and stroke subtype. RESULTS: In 30% of patients the stroke onset time was unknown. 70.7% of patients with acute stroke, and known onset, arrived to the hospital in the first six hours. The median time from onset to admission was: TIA, 2 hours; cerebral infarct, 3 hours (lacunar infarcts 5 hours, non-lacunar infarcts 2 hours) and intracerebral hemorrhage, 2 hours. Patients with severe stroke arrive earlier at the hospital (p < 0.001). Neither sex, age, nor vascular risk factors influence the delay time. CONCLUSIONS: The arrival time varies with stroke subtype: patients with intracerebral hemorrhage or TIA arrive earlier than those with cerebral infarct, and non-lacunar infarcts earlier than lacunar ones. Furthermore, patients with severe stroke are admitted sooner at the hospital.     

Oscillating thromboemboli within the extracranial internal carotid artery demonstrated by ultrasonography in patients with acute cardioembolic stroke

BACKGROUND: Gunshot wounds to the kidney have been managed traditionally by surgical exploration. Concerns over increased nephrectomy rates and unnecessary explorations have placed this method under scrutiny. Selective renal exploration based on solid clinical and radiographic criteria may be a safer alternative and deserves evaluation. METHODS: The medical records of 52 consecutive patients with renal gunshot wounds, who were managed between September 1994 and August 1995 by a protocol of selective exploration, were reviewed. Renal injuries were explored only if they involved the hilum or were accompanied by signs of continued bleeding. Main outcome measures were the numbers of kidneys lost, as well as the morbidity and mortality related to the management of the renal injury. RESULTS: Three patients died from associated injuries shortly after admission. Fifteen patients suffered complications but only two had complications directly associated with the renal injury. Thirty-two patients underwent renal exploration and 17 of them required nephrectomy for major renovascular or parenchymal trauma (grade IV and V). Renal exploration was successfully avoided in the remaining 20 patients. No kidneys were lost unnecessarily as a result of this policy. CONCLUSION: Mandatory exploration of all gunshot wounds to the kidney is not necessary. Injuries that produce stable peripheral haematomas do not require exploration.     

Socioeconomic characteristics of patients with stroke

We studied the socioeconomic status of 206 stroke patients seen at Escola Paulista de Medicina--S?o Paulo in the period of 1991-1992. We found that 25% of patients were less than 50 years old; men were married significantly more often than women; 82% of patients had less than 8 years of formal education and 60% of the families survived with US$ 98 to 198. The socioeconomic impact caused by a stroke is very important. Low education and poverty influence the treatment and prevention of the disease. The Social Assistance Service can detect and attempt to solve the social problems in order to obtain a better control of systemic diseases and risk factors for stroke, and to give orientation concerning the local resources.     

Transcranial magnetic stimulation in patients with cerebellar stroke

Animals engage in a startlingly diverse array of behaviours that depend critically on the time of day or the ability to time short intervals. Timing intervals on the scale of many hours to around a day is mediated by the circadian timing system, while in the range of seconds to hours a different system, known as interval timing, is used. Recent research has illuminated some of the neural mechanisms underlying the 'internal clocks' of these two different timing systems in both animals and humans. Therapeutic applications for humans with impairments in either timing system may ultimately result from these endeavours.     

Asymptomatic cerebral infarctions in patients with ischemic stroke

We studied 383 consecutive patients with stroke and ischemic lesions on CT scan for the presence of symptomatic cerebral infarction (SCI) and asymptomatic cerebral infarction (ACI). We evaluated risk factors as well as volume, site and number of the lesions. ACIs occurred in 34% of the cases (130/383); 88% of ACIs were lacunes and internal borderzone infarctions, with a volume of less than 2 ml. Larger infarctions were asymptomatic in 27 patients (20.8%); 114 (68.7%) out of 166 patients with two or more SCIs (68.7%) had one or more ACIs. Infarctions in the lateral middle cerebral artery (MCA) territory were SCIs, in the medial MCA territory ACIs. Independent risk factors for ACI were age above 70 years and smoking; cardioembolism prevailed in SCI, small vessel disease in ACI; high levels of disability prevailed in SCIs.