Y. L. Yu
University of Hong Kong
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Stroke | 1992
Y. L. Yu; C. R. Kumana; I. J. Lauder; Y. K. Cheung; F.L. Chan; M. Kou; C. M. Chang; Raymond T.F. Cheung; K. Y. Fong
Background and Purpose Hitherto, treatment of acute cerebral hemorrhage with intravenous glycerol has not been evaluated in rigorous clinical studies with sufficient patient numbers. Methods We undertook a double-blind, stratified and randomized, placebo-controlled clinical trial. Only patients with a first stroke admitted to the hospital within 24 hours after onset of symptoms were recruited, provided computed tomography confirmed hemorrhage and informed consent was obtained. After stratification into alert, semicoma, and coma subgroups using the Glasgow Coma Scale, 107 patients received active treatment (500 ml of 10% glycerol in saline by intravenous infusion over 4 hours on 6 consecutive days) and 109 were given corresponding saline treatment. Using a variety of objective scoring systems, patients were followed up for up to 6 months. Results At follow-up, all measures of outcome in the treated and control groups were very similar. At 6 months, respective mortality rates were 37 of 107 and 33 of 109. Corresponding mean±SD improvements in Scandinavian Stroke Study Group scores were 8.35±16.9 versus 11.55±15.6 (long-term) and 0.64±7.3 versus 2.40±6.9 (prognostic), and improvements in the Barthel Index ratings were 10.72±24.7 versus 13.95±23.3, respectively. Glasgow Coma Scale score improvements in the survivors were 0.81±1.5 and 1.16±1.7 in the treated and control groups, respectively. Hemolysis (generally subclinical) was the only adverse effect of glycerol noted. Conclusions In the absence of any clinically or statistically significant difference in outcome between the treated and control groups, this trial provides no justification for glycerol therapy following acute cerebral hemorrhage.s
Stroke | 1988
E. Woo; Y W Chan; Y. L. Yu; C. Y. Huang
In a prospective study to correlate admission glucose level with neurologic outcome in stroke, 252 acute stroke patients without prior disability and admitted within 24 hours of onset of ictus were assessed. The stroke was classified into one of three types--cortical infarct, lacunar infarct, or intracerebral hemorrhage--by clinical, computed tomographic, and necropsy findings. Fifty-one diabetic patients were excluded from the entire cohort to form a nondiabetic category for analysis. We found that admission glucose level showed a significantly higher degree of correlation with mortality and morbidity (measured as arm function, leg function, and activities of daily living) when cortical (n = 118) and lacunar (n = 58) infarcts were pooled compared with when they were assessed separately. For intracerebral hemorrhage (n = 76), admission glucose level correlated with mortality but not morbidity. This trend persisted despite exclusion of diabetic patients. These results are consistent with previous observations of a correlation between a high admission glucose level and the severity of stroke. The importance of segregating cortical from lacunar infarcts, two groups with a different natural history and prognosis, in any future analysis is emphasized.
Stroke | 1988
E. Woo; J. T. C. Ma; J. D. Robinson; Y. L. Yu
To explore further the relation between admission glucose concentration and outcome in stroke, we measured glucose, fructosamine, and glycosylated hemoglobin concentrations on admission in 216 patients seen within 24 hours after the onset of their first stroke. Fructosamine concentration reflects the degree of glycemia in the preceding 4-6 weeks and glycosylated hemoglobin concentration reflects that in the preceding 3 months. Based on clinical, computed tomographic, and necropsy findings, strokes were classified as cortical infarction, lacunar infarction, or intracerebral hemorrhage. Analyses were done including and excluding 47 diabetic patients. No correlation between neurologic outcome as mortality and fructosamine or glycosylated hemoglobin concentration was found. Survival showed a significant correlation with admission glucose concentration only for patients with intracerebral hemorrhage. Our results suggest that hyperglycemia is unlikely to worsen the outcome of acute stroke and that hyperglycemia probably represents either a latent diabetic state or a stress response.
Stroke | 1990
C. Y. Huang; F.L. Chan; Y. L. Yu; E. Woo; D Chin
Our prospective study of cerebrovascular disease in Hong Kong confirms a previous clinical impression that stroke in the Chinese has a pattern different from that in Caucasians. We studied 540 patients (aged 20-70 years) with stroke. Computed tomography or autopsy was obtained in 86.1% and showed an increase in the proportion with lacunar infarction, striatocapsular infarction, and parenchymal hemorrhage relative to the frequencies in Caucasians. This increase in the incidence of cerebral hemorrhage occurs not only in semicomatose and comatose patients but also in alert patients (16.9%) and those with a lacunar syndrome (12.5%). Our findings suggest that cerebrovascular disease in the Chinese selectively affects small vessels, causing lacunes and hemorrhages. In future community studies on stroke prevalence, researchers should be cautious about interpreting similar prevalence rates as reflecting similar risk factors or pathologies.
Acta Neurologica Scandinavica | 1992
Y. L. Yu; B. R. Hawkins; M. S. M. Ip; Virginia Wong; E. Woo
A territory‐wide study of myasthenia gravis (MG) was conducted in Hong Kong. Two hundred and sixty‐two Chinese patients (159 adult and 103 paediatric onset) were identified, corresponding to a point prevalence and period prevalence of 53.5 and 62.2 per million respectively, and an average annual incidence of 4.0 per million population. Nine patients died, 7 from MG, giving a case fatality rate of 0.027. Female predominance was present in the whole group of patients (female to male ratio 1.6:1) and in those with adult disease (ratio 2.1:1), but not in those with onset in childhood (ration 1.1:1). Onset of disease was most common in the first 3 decades of life, and became less common in subsequent decades. Juvenile onset MG occurred in 39.3% of patients and restricted ocular MG in 47.9%. Familial occurrence was found in 5 patients. In the 159 adult onset patients, ocular disease was most common (32.7%), followed by mild generalised (29.6%), moderately severe generalised (24.5%), fulminating (11.9%) and late severe disease (1.3%). The mean age of onset of symptoms was 36.7 years. The symptomatology was similar to that of Caucasoid populations. Autoimmune thyroid disease was the commonest associated disease, and the incidence of thymoma among thymic abnormalities was high at 38%.
Acta Neurologica Scandinavica | 1987
Y. L. Yu; E. Woo; C. Y. Huang
A review of the extensive literature on cervical spondylotic myelopathy and radiculopathy shows that the clinical picture and pathology are well defined, and the complex pathogenetic mechanisms are better understood. With recent advances in investigative procedures: computed tomography, magnetic resonance imaging and somatosensory evoked potentials, the diagnosis can be more accurate and the assessment more complete. Careful selection of patients for the appropriate treatment modality (conservative, anterior or posterior surgery) is crucial to the success in management.
Stroke | 1993
Y. L. Yu; Cr Kumana; Ian J. Lauder; Y. K. Cheung; F.L. Chan; Maybelle Kou; K. Y. Fong; Raymond T.F. Cheung; C. M. Chang
Background and Purpose This clinical trial investigates the effectiveness of intravenous glycerol therapy in patients with acute cortical infarction in whom intracerebral hemorrhage was rigorously excluded. Methods Within 48 hours of symptoms from their first ischemic stroke, 113 hospital inpatients were randomized into the trial, provided that hemorrhage was excluded by computed tomography and informed consent was obtained. Patients were stratified into alert, semicoma, and coma groups using the Glasgow Coma Scale. Treatment was allocated according to a double-blind, randomized protocol; 56 patients received 500 mL of 10% glycerol in saline over 4 hours on 6 consecutive days, and 57 patients received corresponding placebo treatment with saline. Using a variety of objective scoring systems, patient follow-up was up to 6 months. Results Corresponding measures of outcome in the glycerol and placebo groups were similar. At 6 months, respective mortality rates were 17 of 56 and 16 of 57, and mean ±SD improvements in scores were 9.98±14.40 vs 10.51±12.68 (long-term), 1.12±7.20 vs 1.57±6.30 (prognostic), −1.94±5.53 vs −2.06±5.34 (Glasgow Coma Scale), and 21.72±23.40 vs 11.94± 18.10 (Barthel Index rating in survivors). Hemolysis (generally subclinical) was the only adverse effect. Conclusions There was no clinically or statistically significant difference in outcome between the groups; a trend toward greater functional recovery among survivors was evident after treatment with glycerol.
Diabetes Research and Clinical Practice | 1991
K.S.L. Lam; J. T. C. Ma; E. Woo; Clk Lam; Y. L. Yu
We reviewed the prevalence of diabetes mellitus, hypertension and cigarette smoking in 176 Chinese patients with acute stroke, classified, on computed tomographic findings, as intracerebral haemorrhage or cerebral infarction. In all patients with no known history of diabetes, a 75 g OGTT was done 3-6 months after ictus and interpreted using WHO criteria. The overall prevalence of diabetes and impaired glucose tolerance (IGT) was 33.5% and 21.0%, respectively, with a higher prevalence being found in patients with cerebral infarction (P less than 0.05). Forty percent of those with diabetes were previously undiagnosed - all but 2 had ischaemic stroke. Compared to reported findings in the general population, an increased prevalence of hypertension, and possibly also cigarette smoking was found in patients with both stroke categories. On the other hand, significant hypercholesterolaemia was not found in patients of either category. In view of the high prevalence of undiagnosed diabetes among these stroke patients and the increased morbidity and mortality associated with diabetes mellitus, screening for diabetes is recommended especially in those with ischaemic stroke. If a fasting plasma glucose of greater than or equal to 6 mmol/l was used for the initial screening of undiagnosed diabetes in this group of patients, the sensitivity and specificity values would have been 78% and 94%, respectively. Whether this cut-off value can be cost-effectively employed for mass screening remains to be confirmed by studies involving larger numbers of stroke patients.
Pathology | 1987
E. Woo; Yuen Fu Chan; Karen Lam; Anna S.F. Lok; Y. L. Yu; Chen Ya Huang
&NA; A patient with apoplectic intracerebral hemorrhage from delayed cerebral radionecrosis is reported. The histological changes of abnormal telangiectatic vessels account for the unusual clinical presentation. The pathogenesis and treatment of radionecrosis are discussed, and massive hemorrhage as a complication is emphasized.
Neuroradiology | 1987
Y. L. Kwong; Y. L. Yu; K.S.L. Lam; E. Woo; J. T. C. Ma; C. Y. Huang
Four months prior to admission this 23-year-old secretary developed blurting of vision and dizziness. Blood pressure was 300/170 mm Hg. Blood counts, electrolytes, renal function and intravenous urography were normal. Urinary ca~echolamines and VMAs were persistently elevated. On admission for uncontrolled hypertension (200/160 mm Hg), she was drowsy and disorientated, with papilloedema, multiple retinal haemorrhages and exudates, and left heart hypertrophy, but no focal neurological deficits. She went into acute pulmonary oedema next day. Malignant hypertension secondary to phaeochromocytoma was diagnosed. CT brain scan (Fig.l), performed immediately after admission without contrast as this might provoke a surge of catecholamines, showed extensive low attenuation in the white matter of the cerebral hemispheres and cerebellum. There was compression of the ventricular system and obliteration of peripheral sulci. Blood pressure and pulmonary oedema responded to treatment. Her mental state became normal on day 10. CT (plain and contrast) repeated 3 weeks later showed significant resolution of swelling and low attenuation. CT 6 months later was normal.