30 results on '"Siu DY"'
Search Results
2. A 45-year-old woman with reversible bilateral hearing loss.
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Woo PY, Teoh JY, Wong GK, Zhu XL, Siu DY, Kwan MC, Poon WS, Woo, Peter Yat Ming, Teoh, Jeremy Yuen Chun, Wong, George Kwok Chu, Zhu, Xian Lun, Siu, Deyond Yung Woon, Kwan, Marco Cheuk Lun, and Poon, Wai Sang
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- 2013
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3. Title.
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Poon TL, Lui CH, Chan I, and Siu DY
- Abstract
Epilepsy is defined as drug-resistant after failure of two adequate trials of appropriately chosen and administered antiepileptic drugs. Approximately 30% of patients with epilepsy have drug-resistant epilepsy. Reasons for treatment failure include failure to recognise epilepsy syndrome, poor drug compliance, and lifestyle factors. Patients with drug-resistant epilepsy should be encouraged to have early referral to a tertiary epilepsy centre for presurgical evaluation. Comprehensive neurophysiology, structural neuroimaging, neuropsychological, and psychiatric assessments are regarded as essential for determining suitability for epilepsy surgery. Epilepsy surgery, whether resection, disconnection, or neuromodulation, should be recommended only after multidisciplinary consensus agreement based on these assessments.
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- 2018
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4. Clinically important difference of Stroke-Specific Quality of Life Scale for aneurysmal subarachnoid hemorrhage.
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Wong GK, Lee A, Wong A, Ho FL, Leung SL, Zee BC, Poon WS, Siu DY, Abrigo JM, and Mok VC
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- Activities of Daily Living, Adult, Aged, Cost of Illness, Disease Progression, Female, Hong Kong, Humans, Language, Male, Middle Aged, Neuropsychological Tests, Treatment Outcome, Quality of Life, Stroke psychology, Subarachnoid Hemorrhage psychology
- Abstract
Health-related quality of life measurements, are commonly used to quantify burden of disease, to evaluate treatment method, and to facilitate benchmarking. The aim of the current study was to determine the Clinically Important Difference (CID) for a Chinese version of Stroke-specific Quality of Life (SS-QOL) in an aneurysmal subarachnoid hemorrhage (SAH) patient cohort. The study recruited SAH patients in a neurosurgical unit in Hong Kong. SAH patients who completed both 3-month and 1-year assessments were included in the analysis. The study received ethical approvals from the joint CUHK-NTEC Clinical Ethics Committee and written informed consent was obtained from all participants or their next of kins. Over a 2-year period, 65 eligible patients were included in the study. Employing the anchor-based approach with global rating of change, the CID estimate of SS-QOL total score was 4.7 (95% confidence interval [CI]: 2.5-5.3), the CID estimate for SSQOL physical subscore was 2.1 (95% CI: 0.3-2.4), and the CID estimate for SS-QOL psychosocial subscore change was 2.8 (95% CI: 1.8-3.7). In conclusion, our study defined the CID for SS-QOL applied to SAH patients and should be further validated in another SAH patient population., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
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- 2016
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5. Screening for intracranial aneurysms? Prevalence of unruptured intracranial aneurysms in Hong Kong Chinese.
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Chan DY, Abrigo JM, Cheung TC, Siu DY, Poon WS, Ahuja AT, and Wong GK
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- Adult, Cerebral Angiography, Cross-Sectional Studies, Female, Humans, Intracranial Aneurysm diagnostic imaging, Intracranial Aneurysm genetics, Magnetic Resonance Angiography, Male, Middle Aged, Subarachnoid Hemorrhage diagnostic imaging, Subarachnoid Hemorrhage epidemiology, Subarachnoid Hemorrhage ethnology, Subarachnoid Hemorrhage genetics, Tomography, X-Ray Computed, Asian People statistics & numerical data, Intracranial Aneurysm epidemiology, Intracranial Aneurysm ethnology, Mass Screening
- Abstract
OBJECT The objective of this study was to generate data on the local prevalence of unruptured intracranial aneurysms (UIAs) in asymptomatic Hong Kong Chinese individuals. First-degree relatives of patients with aneurysmal subarachnoid hemorrhage (aSAH) were recruited as surrogates of the general population and to explore the potential role of screening in this locality. METHODS The authors identified first-degree relatives of consecutive patients with subarachnoid hemorrhage from a ruptured aneurysm who were admitted to a university hospital in Hong Kong from June 2008 to December 2010. Magnetic resonance angiography (MRA) was the imaging modality used to screen the cerebral vasculature of these asymptomatic individuals. If MRA showed abnormal findings, CT angiography was performed to confirm the MRA findings. RESULTS In total, 7 UIAs were identified from the 305 MR angiograms obtained. The prevalence of UIAs in first-degree relatives of patients with aSAH in the Hong Kong Chinese population was 2.30% (95% CI1.02%-4.76%). This percentage was lower than the prevalence rate of 3.2% from a meta-analysis of the literature. The sizes of the UIAs detected ranged from 1.4 mm to 7.5 mm; 85.7% of the UIAs detected in this study were < 5 mm, in contrast to 66% noted in the literature. One of the UIAs identified underwent endovascular stent placement with a flow diverter. None of the UIAs identified ruptured or became symptomatic during a median follow-up period of 3.5 years. CONCLUSIONS The prevalence of UIAs in first-degree relatives of patients with aSAH in the Hong Kong Chinese population was lower than that in Caucasians. At the same time, most of the UIAs detected in this study were small (85.7% were < 5 mm, vs 66% in a meta-analysis). With a similar incidence of aSAH in Hong Kong (7.5 per 100,000 person-years) as compared with data cited in the literature, the hypothesis that UIA rupture risk size threshold is different in Chinese patients should be further investigated.
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- 2016
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6. Early Cerebral Infarction after Aneurysmal Subarachnoid Hemorrhage.
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Wong GK, Leung JH, Yu JW, Lam SW, Chan EK, Poon WS, Abrigo J, and Siu DY
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- Adult, Brain Infarction, Cerebral Infarction diagnostic imaging, Cohort Studies, Disease Progression, Endovascular Procedures, Female, Hong Kong epidemiology, Humans, Male, Middle Aged, Multivariate Analysis, Neurosurgical Procedures, Prospective Studies, Risk Factors, Subarachnoid Hemorrhage diagnostic imaging, Subarachnoid Hemorrhage surgery, Surgical Instruments, Time Factors, Tomography, X-Ray Computed, Cerebral Infarction epidemiology, Subarachnoid Hemorrhage epidemiology
- Abstract
Aneurysmal subarachnoid hemorrhage (SAH) is a serious disease with high case fatality and morbidity. Early cerebral infarction has been suggested as a risk factor for poor outcome. We aimed to assess the pattern of early and delayed cerebral infarction after aneurysmal subarachnoid hemorrhage. We prospectively enrolled consecutive aneurysmal subarachnoid hemorrhage (SAH) patients presenting to an academic neurosurgical referral center (Prince of Wales Hospital, the Chinese University of Hong Kong) in Hong Kong. Cerebral infarction occurred in 24 (48 %) patients, in which 14 (28 %) had early cerebral infarction and 14 (28 %) had delayed cerebral infarction. Early anterior cerebral infarction occurred in a similar proportion of anterior and posterior circulation aneurysms (24 % vs. 21 %), whereas posterior circulation aneurysm patients had a higher proportion of early posterior cerebral infarction compared with anterior circulation aneurysm patients (18 % vs. 2 %). In conclusion, early cerebral infarction was common and different from delayed cerebral infarction.
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- 2016
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7. Cognitive outcome in acute simvastatin treatment for aneurysmal subarachnoid hemorrhage: A propensity matched analysis.
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Wong GK, Wong A, Zee BC, Poon WS, Chan MT, Gin T, Siu DY, and Mok VC
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- Aged, Cognition Disorders etiology, Double-Blind Method, Female, Humans, Hydroxymethylglutaryl-CoA Reductase Inhibitors administration & dosage, Male, Middle Aged, Propensity Score, Simvastatin administration & dosage, Subarachnoid Hemorrhage complications, Treatment Outcome, Cognition Disorders drug therapy, Hydroxymethylglutaryl-CoA Reductase Inhibitors pharmacology, Simvastatin pharmacology, Subarachnoid Hemorrhage drug therapy
- Abstract
Objectives: Experimental evidence has indicated the benefit of simvastatin in the treatment of subarachnoid hemorrhage (SAH). Recently, acute simvastatin treatment was not shown to be beneficial in neurological outcome using modified Rankin Scale. Cognitive function is another important dimension of outcome assessment and yet had not been investigated in statin studies for aneurysmal subarachnoid hemorrhage. We therefore explored whether acute simvastatin treatment would improve cognitive outcomes., Methods: The study recruited SAH patients with acute simvastatin treatment enrolled in a randomized controlled double-blinded clinical trial (ClinicalTrials.gov Identifier: NCT01038193). A control cohort of SAH patients without simvastatin treatment was identified with propensity score matching of age and admission grade. Primary outcome measure was Montreal Cognitive Assessment (MoCA). Secondary outcome measures were delayed ischaemic deficit (DID), delayed cerebral infarction, modified Rankin Scale (mRS), and Mini-Mental State Examination (MMSE)., Results: Fifty-one SAH patients with acute simvastatin treatment and 51 SAH patients without simvastatin treatment were recruited for analysis. At 3 months, there were no differences in MoCA scores (MoCA: 21+/-6 vs. 21+/-5, p=0.772). MoCA-assessed cognitive impairment (MoCA<26) was not different (75% vs. 80%, OR 0.7, 95%CI 0.3 to 1.8, p=0.477). There were also no differences in DID, delayed cerebral infarction, favorable mRS outcome, and MMSE scores, and MMSE-assessed cognitive impairment between both groups., Conclusions: The current study does not support that acute simvastatin treatment improves cognitive outcome after aneurysmal subarachnoid hemorrhage., (Copyright © 2015 Elsevier B.V. All rights reserved.)
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- 2015
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8. Location, Infarct Load, and 3-Month Outcomes of Delayed Cerebral Infarction After Aneurysmal Subarachnoid Hemorrhage.
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Wong GK, Nung RC, Sitt JC, Mok VC, Wong A, Ho FL, Poon WS, Wang D, Abrigo J, and Siu DY
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- Adult, Aged, Female, Follow-Up Studies, Humans, Male, Middle Aged, Prospective Studies, Risk Factors, Time Factors, Treatment Outcome, Cerebral Infarction diagnosis, Cerebral Infarction etiology, Intracranial Aneurysm complications, Intracranial Aneurysm diagnosis, Subarachnoid Hemorrhage complications, Subarachnoid Hemorrhage diagnosis
- Abstract
Background and Purpose: Aneurysmal subarachnoid hemorrhage is a serious disease with high case fatality and morbidity. Delayed cerebral infarction (DCI) is an important surrogate marker. How location and infarct load affected outcomes was unclear. We aimed to assess the effects of load and location of DCI on outcomes of aneurysmal subarachnoid hemorrhage at 3 months., Methods: We prospectively enrolled patients with subarachnoid hemorrhage presenting to an academic neurosurgical unit in Hong Kong during a 3-year period. DCI was defined by new hypoattenuation on computed tomography at 4 to 6 weeks, which was not present in the postaneurysm-treatment computed tomography at 24 to 48 hours. DCI was assessed for location according to cerebral artery territories and load semiquantitatively. Cognitive and functional outcome assessments were carried out 3 months after ictus., Results: One hundred twenty-six patients with subarachnoid hemorrhage consented for this study. DCI occurred in 56 (44%) patients and was associated with poorer cognitive and functional outcomes (Montreal Cognitive Assessment, Mini-Mental State Examination, modified Rankin Scale, and Lawton Instrumental Activity of Daily Living) at 3 months. In patients with DCI, the presence of perforator zone infarct was associated with poorer cognitive and functional outcomes, and cortical middle cerebral artery infarct was associated with poorer modified Rankin Scale. After adjustment for age, admission World Federation of Neurosurgical Societies Grade and mode of aneurysm treatment, both middle cerebral artery cortical infarct load and perforator infarct load were independently associated with poor cognitive outcomes (Montreal Cognitive Assessment and Mini-Mental State Examination) and modified Rankin Scale., Conclusions: Middle cerebral artery cortical and perforator zone infarct loads are potential surrogate marker to assess the severity of delayed cerebral ischemia., (© 2015 American Heart Association, Inc.)
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- 2015
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9. High-dose simvastatin for aneurysmal subarachnoid hemorrhage: multicenter randomized controlled double-blinded clinical trial.
- Author
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Wong GK, Chan DY, Siu DY, Zee BC, Poon WS, Chan MT, Gin T, and Leung M
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- Adult, Aged, Double-Blind Method, Female, Follow-Up Studies, Humans, Male, Middle Aged, Treatment Outcome, Hydroxymethylglutaryl-CoA Reductase Inhibitors administration & dosage, Simvastatin administration & dosage, Subarachnoid Hemorrhage diagnosis, Subarachnoid Hemorrhage drug therapy
- Abstract
Background and Purpose: Experimental evidence has indicated the benefits of simvastatin for the treatment of subarachnoid hemorrhage. Two randomized placebo-controlled pilot trials that used the highest clinically approved dose of simvastatin (80 mg daily) gave positive results despite the fact that a lower dose of simvastatin (40 mg daily) did not improve clinical outcomes. We hypothesized that a high dose of 80 mg of simvastatin daily for 3 weeks would reduce the incidence of delayed ischemic deficits after subarachnoid hemorrhage compared with a lower dose (40 mg of simvastatin daily) and lead to improved clinical outcomes., Methods: The study design was a randomized controlled double-blinded clinical trial. Patients with aneurysmal subarachnoid hemorrhage (presenting within 96 hours of the ictus) from 6 neurosurgical centers were recruited for 3 years. The primary outcome measure was the presence of delayed ischemic deficits, and secondary outcome measures included a modified Rankin disability score at 3 months and an analysis of cost-effectiveness., Results: No difference was observed between the groups treated with the higher dose or the lower dose of simvastatin in the incidence of delayed ischemic deficits (27% versus 24%; odds ratio, 1.2; 95% confidence interval, 0.7-2.0; P=0.586) or in the rate of favorable outcomes (modified Rankin Scale score, 0-2) at 3 months (73% versus 72%; odds ratio, 1.1; 95% confidence interval, 0.6-1.9; P=0.770)., Conclusions: High-dose simvastatin treatment should not be prescribed routinely for aneurysmal subarachnoid hemorrhage., Clinical Trial Registration Url: http://www.clinicaltrials.gov. Unique identifier: NCT01077206., (© 2014 American Heart Association, Inc.)
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- 2015
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10. Atypical intracranial epidermoid cysts: rare anomalies with unique radiological features.
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Law EK, Lee RK, Ng AW, Siu DY, and Ng HK
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Epidermoid cysts are benign slow growing extra-axial tumours that insinuate between brain structures, while their occurrences in intra-axial or intradiploic locations are exceptionally rare. We present the clinical, imaging, and pathological findings in two patients with atypical epidermoid cysts. CT and MRI findings for the first case revealed an intraparenchymal epidermoid cyst that demonstrated no restricted diffusion. The second case demonstrated an aggressive epidermoid cyst that invaded into the intradiploic spaces, transverse sinus, and the calvarium. The timing of ectodermal tissue sequestration during fetal development may account for the occurrence of atypical epidermoid cysts.
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- 2015
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11. Spontaneous intracranial hypotension: improving recognition and treatment strategies in the local setting.
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Lee GK, Abrigo JM, Cheung TC, Siu DY, and Chan DT
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- Diagnosis, Differential, Headache etiology, Hematoma, Subdural complications, Hematoma, Subdural diagnostic imaging, Humans, Intracranial Hypotension complications, Intracranial Hypotension surgery, Magnetic Resonance Imaging, Male, Middle Aged, Tomography, X-Ray Computed, Hematoma, Subdural diagnosis, Intracranial Hypotension diagnosis
- Abstract
We report a case of spontaneous intracranial hypotension with classic symptoms of orthostatic headache and acute presentation of subdural haematoma on computed tomographic scan. Conventional approach with conservative treatment was initially adopted. The patient's condition, however, deteriorated after 2 weeks, requiring surgical evacuation of the intracranial haemorrhage. We reviewed the clinical features of this disease and the correlated magnetic resonance imaging findings with the pathophysiological mechanisms, and described treatment strategies in the local setting. Subtle findings on initial computed tomographic scan are also reported which might improve pathology recognition. Spontaneous intracranial hypotension is not uncommonly encountered in Hong Kong, and physicians must adopt a high level of clinical suspicion to facilitate early diagnosis and appropriate management. In addition, novel therapeutic approaches may be required in those with recurrent symptoms or who are refractory to current treatment strategies.
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- 2014
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12. Performance of serum α-fetoprotein levels in the diagnosis of hepatocellular carcinoma in patients with a hepatic mass.
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Chan SL, Mo F, Johnson PJ, Siu DY, Chan MH, Lau WY, Lai PB, Lam CW, Yeo W, and Yu SC
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- Adult, Aged, Area Under Curve, Asian People, Carcinoma, Hepatocellular ethnology, Carcinoma, Hepatocellular pathology, Carcinoma, Hepatocellular virology, China epidemiology, Hepatitis B, Chronic blood, Hepatitis B, Chronic ethnology, Humans, Liver Neoplasms ethnology, Liver Neoplasms pathology, Liver Neoplasms virology, Male, Middle Aged, Predictive Value of Tests, ROC Curve, Reproducibility of Results, Retrospective Studies, Risk Factors, Carcinoma, Hepatocellular blood, Liver Neoplasms blood, alpha-Fetoproteins analysis
- Abstract
Objectives: The role of serum α-fetoprotein (AFP) measurements in the diagnosis of hepatocellular carcinoma (HCC) remains controversial. Some guidelines have advised against the use of AFP in the diagnosis of HCC. This study was conducted to evaluate the performance of AFP in the diagnosis of HCC, and to identify the optimal cut-off value of serum AFP in the diagnosis of HCC in patients with a hepatic mass., Methods: Patients who presented during the period from May 1997 to March 2003 with hepatic lesions, for whom paired data on serum AFP values at baseline and lesion histology were available, were reviewed. The performance of AFP in the diagnosis of HCC was determined using receiver operating characteristic curve analysis., Results: Data for a total of 805 patients were evaluated. The mean AFP value was 26,900 ng/ml (range: 0-1,965,461 ng/ml). The histological diagnosis was HCC in 557 patients. The optimal AFP cut-off value was 10 ng/ml (for sensitivity of 82.6% and specificity of 70.4%). At a cut-off level of 200 ng/ml, sensitivity, specificity, and positive and negative predictive values were 47.7%, 97.1%, 97.5% and 44.4%, respectively. The diagnostic performance of AFP remains similar in patients with chronic hepatitis B virus infection, despite a lower negative predictive value. Common aetiologies of liver lesions associated with elevated AFP include cholangiocarcinoma and neuroendocrine tumours., Conclusions: In Asian patients with suspicious liver lesions, the cut-off AFP level of 200 ng/ml is useful to achieve a diagnosis of HCC with high specificity and reasonable sensitivity. The measurement of serum AFP should not be excluded from guidelines for the diagnosis of HCC., (© 2013 International Hepato-Pancreato-Biliary Association.)
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- 2014
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13. A sequential comparison on the risk of haemorrhage with different sizes of biopsy needles for stereotactic brain biopsy.
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Yuen J, Zhu CX, Chan DT, Ng RY, Nia W, Poon WS, Ng HK, Mok VC, Wong LK, Cheung TC, and Siu DY
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- Adolescent, Adult, Aged, Aged, 80 and over, Biopsy, Needle adverse effects, Brain Neoplasms surgery, Cerebral Hemorrhage etiology, Cerebral Hemorrhage prevention & control, Cohort Studies, Female, Humans, Male, Middle Aged, Postoperative Complications etiology, Postoperative Complications prevention & control, Prospective Studies, Risk Factors, Stereotaxic Techniques adverse effects, Young Adult, Biopsy, Needle standards, Brain Neoplasms diagnosis, Cerebral Hemorrhage diagnosis, Postoperative Complications diagnosis, Stereotaxic Techniques instrumentation
- Abstract
Aim: To compare the risk of postoperative haemorrhage with different sizes of brain biopsy needles., Patients and Method: A cohort of patients using a 2.5-mm outer diameter side-cutting biopsy needle was compared to a subsequent cohort using a 1.8-mm needle of the same type. All data were collected prospectively. A CT scan was done within 12 h after surgery. Any visible haemorrhage at the operated site was documented., Results: From 2007 to 2013, 54 stereotactic brain biopsies (all frameless except for one frame-based) were performed. The 2.5-mm group comprised 29 procedures from 2007 to 2009. The 1.8-mm group comprised the subsequent 25 procedures. The diagnostic yields were 90 and 96% in the 2.5- and the 1.8-mm group, respectively (p = 0.615). Comparing the 2.5- and the 1.8-mm group, haemorrhage was significantly reduced: incidence (72 vs. 40%, p = 0.016); size of haemorrhage (mean 7.2 vs. 2.6 mm, p = 0.002); proportion of haemorrhage size >10 mm (34.5 vs. 4%, p = 0.006). Symptomatic haemorrhage rates were 3.4 and 0.0% in the 2.5- and the 1.8-mm group, respectively (p = 1.00)., Conclusion: The 1.8-mm outer diameter needle carried a lower risk of postoperative haemorrhage than the 2.5-mm one, without compromising the diagnostic yield.
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- 2014
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14. Spinal nerve root haemangioblastoma associated with reactive polycythemia.
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Law EK, Lee RK, Griffith JF, Siu DY, and Ng HK
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Haemangioblastomas are uncommon tumours that usually occur in the cerebellum and, less commonly, in the intramedullary spinal cord. The extramedullary spinal canal is an uncommon location for these tumours. Also haemangioblastoma at this site is not known to be associated with polycythemia. We present the clinical, imaging, and histological findings of an adult patient with extramedullary spinal haemangioblastoma and reactive polycythemia. Radiography and computed tomography (CT) revealed a medium-sized tumour that most likely arose from an extramedullary spinal nerve root. This tumour appeared to be slow growing as evidenced by the accompanying well-defined bony resorption with a sclerotic rim and mild neural foraminal widening. Magnetic resonance imaging revealed prominent flow voids consistent with tumoural hypervascularity. CT-guided biopsy was performed. Although preoperative angiographic embolisation was technically successful, excessive intraoperative tumour bleeding necessitated tumour debulking rather than complete tumour resection. Histology of the resected specimen revealed haemangioblastoma. Seven months postoperatively, the patients back pain and polycythemia have resolved.
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- 2014
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15. Intra-arterial revascularisation therapy for acute ischaemic stroke: initial experience in a Hong Kong hospital.
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Wong EH, Yu SC, Lau AY, Hui VS, Leung CS, Hui JW, Siu DY, Abrigo JM, Lee KT, Graham CA, Wong LK, and Leung TW
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- Aged, Aged, 80 and over, Angioplasty, Balloon methods, Brain Ischemia complications, Brain Ischemia diagnosis, Brain Ischemia therapy, Cohort Studies, Combined Modality Therapy, Emergency Treatment, Female, Follow-Up Studies, Hong Kong, Hospital Mortality, Humans, Magnetic Resonance Imaging methods, Male, Middle Aged, Retrospective Studies, Risk Assessment, Severity of Illness Index, Stroke diagnosis, Stroke etiology, Survival Rate, Tertiary Care Centers, Thrombectomy methods, Tomography, X-Ray Computed methods, Treatment Outcome, Endovascular Procedures methods, Stroke mortality, Stroke therapy, Thrombolytic Therapy methods, Tissue Plasminogen Activator therapeutic use
- Abstract
Objectives: To assess the outcome of acute ischaemic stroke patients who received intra-arterial therapy in our unit., Design: Case series., Setting: A tertiary hospital in Hong Kong., Patients: Patients with ischaemic stroke due to large artery occlusion treated within 6 hours from symptom onset between January 2007 and May 2011., Intervention: Acute intra-arterial revascularisation therapy., Main Outcome Measures: Primary outcome was functional independence (modified Rankin Scale score of ≤ 2) at 3 months. Secondary outcome was rate of recanalisation. Safety outcomes were symptomatic intracranial haemorrhage and 3-month mortality., Results: Twenty-one patients with a mean age of 67 years fulfilled the inclusion criteria. Their mean National Institutes of Health Stroke Scale score was 18. The mean onset-to-puncture time was 212 minutes. Nine received intra-arterial tissue plasminogen activator alone, 11 had an adjunctive mechanical thrombectomy, and one received balloon angioplasty without tissue plasminogen activator. At the end of the procedure, thrombolysis grade 2a or better was attained in 18 (86%) of the patients, and 8 (38%) achieved functional independence at 3 months. Rates of symptomatic intracranial haemorrhage and 3-month mortality were 10% and 24%, respectively., Conclusion: In this setting, intra-arterial revascularisation therapy appeared safe and efficacious for this selected group of ischaemic stroke patients with large artery occlusions. Experience gained from this pilot study may help improve clinical outcomes of such patients.
- Published
- 2013
16. An uncommon mimic of spontaneous subarachnoid haemorrhage.
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Ng RY, Siu DY, Wong GK, Ng HK, and Poon WS
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- Adult, Biopsy, Female, Humans, Subarachnoid Hemorrhage pathology, Tomography, X-Ray Computed, Melanocytes pathology, Meninges pathology, Subarachnoid Hemorrhage diagnosis
- Abstract
We here presented a rare disease entity with a clinical presentation mimicking aneurysmal subarachnoid haemorrhage. A 43-year-old woman presented with a 1-week history of neck pain and dizziness. Computed tomography of brain showed communicating hydrocephalus and subarachnoid hyperintensity suspicious of previous subarachnoid haemorrhage. Investigations revealed no underlying vascular lesion and leptomeningeal biopsy showed diffuse melanocytosis. We go on to discuss the diagnostic features and clinical course of this entity.
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- 2013
17. Pseudoprogression of malignant glioma in Chinese patients receiving concomitant chemoradiotherapy.
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Chan DT, Ng RY, Siu DY, Tang P, Kam MK, Ma BB, Wong GK, Ng SC, Pang JC, Lau CK, Zhu XL, Ng HK, and Poon WS
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- Adolescent, Adult, Aged, Antineoplastic Agents, Alkylating adverse effects, Asian People, Biomarkers, Tumor, Brain Neoplasms genetics, Chemoradiotherapy, DNA Methylation, Disease Progression, Glioblastoma genetics, Glioma genetics, Humans, Magnetic Resonance Imaging, Middle Aged, Treatment Outcome, Young Adult, Antineoplastic Agents, Alkylating therapeutic use, Brain Neoplasms therapy, DNA Modification Methylases genetics, Glioblastoma therapy, Glioma therapy, O(6)-Methylguanine-DNA Methyltransferase genetics
- Abstract
Objectives: To investigate the frequency of pseudoprogression of glioblastoma in Chinese patients receiving concomitant chemoradiotherapy and investigate its association with pseudoprogression and tumour molecular marker O(6)-methylguanine-DNA methyltransferase promoter methylation status., Design: Case series with internal comparisons., Setting: University teaching hospital, Hong Kong., Patients: Patients with glioblastoma treated with concomitant chemoradiotherapy during April 2005 to June 2010 were reviewed. Magnetic resonance imaging brain scans, pre- and post-concomitant chemoradiotherapy and 3-monthly thereafter were reviewed by an independent neuroradiologist according to Macdonald's criteria. Relevant patient information (clinical condition, performance score, development of new neurological deficits, use of steroids, and survival) was retrieved. For each patient, O(6)-methylguanine-DNA methyltransferase methylation status was investigated with genomic DNA from formalin-fixed or paraffin-embedded sections of tumour tissues by methylation-specific polymerase chain reaction., Results: During the study period, 28 primary glioblastoma patients underwent concomitant chemoradiotherapy. The mean age of the patients was 48 (range, 16-71) years. Thirteen patients (13/28, 46%) developed early radiological progression of the tumour after completion of concomitant chemoradiotherapy, of whom five (39%) were subsequently found to have had pseudoprogression. Patients with pseudoprogression showed a trend towards longer survival (22 months in pseudoprogression vs 17 months in all others vs 11 months in those with genuine progression). Among the 27 patients tested for O(6)-methylguanine-DNA methyltransferase promoter status, 12 (44%) were methylated. Two (2/12, 17%) in the methylated group had pseudoprogression, while three (3/15, 20%) in the unmethylated group had pseudoprogression., Conclusions: Nearly half of all patients (46%) developed early radiological progression (within 3 months of completing concomitant chemoradiotherapy). Moreover, about one in three of such patients had pseudoprogression. Pseudoprogression is an important clinical condition to be aware of to prevent premature termination of an effective treatment.
- Published
- 2012
18. Risk of intracerebral hemorrhage in patients with cerebral microbleeds undergoing endovascular intervention.
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Soo YO, Siu DY, Abrigo J, Yu S, Ng N, Ahuja AT, Wong LK, and Leung TW
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- Aged, Aged, 80 and over, Aspirin adverse effects, Atherosclerosis therapy, Brain Ischemia complications, Clopidogrel, Female, Humans, Male, Middle Aged, Platelet Aggregation Inhibitors adverse effects, Retrospective Studies, Risk Factors, Stroke complications, Ticlopidine administration & dosage, Ticlopidine adverse effects, Aspirin administration & dosage, Brain Ischemia therapy, Cerebral Hemorrhage etiology, Endovascular Procedures, Platelet Aggregation Inhibitors administration & dosage, Stroke therapy, Ticlopidine analogs & derivatives
- Abstract
Background and Purpose: Cerebral microbleeds (CMBs) on MRI gradient echo images are hemosiderin deposits, which may predict intracerebral hemorrhage (ICH). The risk of ICH in patients with CMBs could be exacerbated by the use of antithrombotics. The purpose of our study is to prospectively evaluate the risk of ICH in patients with ischemic stroke who receive dual antiplatelet therapy for endovascular intervention., Methods: We analyzed MRI of 133 patients admitted consecutively for intra- and extracranial stenting for symptomatic large artery atherosclerosis who received aspirin and clopidogrel. Quantity and location of CMBs were recorded by neuroradiologists independent from the angioplasty team. The primary end point was symptomatic ICH as evident in CT of the brain within 12 weeks of procedure., Results: CMBs were identified in 23 patients. Mean number of CMBs was 2.3 ± 1.6. Four patients had >5 CMBs. Forty-seven patients had intracranial stents, 84 patients had extracranial stents, and 2 patients had both intracranial and extracranial stents. There was no difference in risk of symptomatic ICH between those with (4.3%) and without CMBs (5.5%) patient with CMBs (P=1.000)., Conclusions: The presence of a small number of CMBs does not cause a large increase in the short-term risk of symptomatic ICH in patients with ischemic stroke who undergo endovascular intervention with dual antiplatelet therapy. The risk of ICH in patients with ≥ 5 CMBs, however, remains unclear. Further studies with a larger sample size of patients with multiple CMBs are needed.
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- 2012
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19. Recanalization with subsequent near-total occlusion of an internal carotid artery aneurysm after immediate thrombotic occlusion using a flow-diverting stent.
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Wong GK, Yu SC, Siu DY, and Poon WS
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- Aneurysm diagnostic imaging, Angiography, Digital Subtraction, Carotid Artery Diseases diagnostic imaging, Carotid Artery Thrombosis diagnostic imaging, Cerebral Angiography, Embolization, Therapeutic, Equipment Failure, Humans, Male, Middle Aged, Recurrence, Retreatment, Subarachnoid Hemorrhage diagnostic imaging, Subarachnoid Hemorrhage therapy, Tomography, X-Ray Computed, Treatment Failure, Aneurysm therapy, Carotid Artery Diseases therapy, Carotid Artery Thrombosis therapy, Carotid Artery, Internal diagnostic imaging, Stents
- Abstract
A flow-diverting stent is placed in the parent artery to reduce blood flow in the aneurysm sac to facilitate progressive thrombosis and neointimal remodeling while maintaining outflow in the side branches and perforators. All international multicenter registries have reported on the progressive occlusion of aneurysms with time and have implied that an occluded aneurysm would not recanalize given the protective effect of the altered hemodynamics. Recanalization of an occluded aneurysm after placement of a flow-diverting stent has not been reported in the literature. The authors here describe a case of aneurysm recanalization after immediate thrombotic occlusion of the aneurysm with a flow-diverting stent. A 46-year-old male chronic smoker with chronic hypertension and hypercholesterolemia had a recurrent internal carotid artery aneurysm 1 year after embolization. Immediate thrombotic occlusion of the aneurysm and cessation of blood flow to the posterior communicating artery (PCoA) occurred immediately after activating a flow-diverting stent, with corresponding ischemic complications. However, 3 months after insertion of the stent, follow-up MR angiography showed recanalization of the aneurysm as well as of the PCoA. Additional angiography studies at 6 months showed near-total occlusion of the aneurysm with the restoration of blood flow to the PCoA.
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- 2012
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20. Is stroke thrombolysis safe and efficacious in Hong Kong?
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Wong EH, Lau AY, Soo YO, Siu DY, Hui VS, Graham CA, Leung TW, and Wong LK
- Subjects
- Aged, Aged, 80 and over, Brain Ischemia mortality, Cohort Studies, Female, Hong Kong, Humans, Length of Stay, Male, Middle Aged, Stroke mortality, Brain Ischemia drug therapy, Stroke drug therapy, Thrombolytic Therapy adverse effects
- Abstract
Objective: To investigate the safety and efficacy of stroke thrombolysis in a local hospital., Design: Historical cohort study., Setting: A tertiary hospital in Hong Kong., Patients: The outcome of acute ischaemic stroke patients treated with intravenous tissue plasminogen activator between October 2008 and May 2011 was compared to those admitted during the same period who were thrombolysis-eligible, but treated conservatively due to unavailability of the thrombolysis service after-hours., Interventions: Intravenous tissue plasminogen activator., Main Outcome Measures: Primary outcome was functional independence (modified Rankin Scale score of 2 or below) at 3 months. Safety outcomes were symptomatic intracranial haemorrhage and 3-month mortality. Secondary outcomes were hospital length of stay, direct home discharge, and nursing home discharge., Results: A total of 48 thrombolysis and 63 non-thrombolysis patients were identified. Fifty-two percent of the thrombolysis group achieved functional independence compared to 24% of non-thrombolysis group (P=0.003), without significant increase in mortality (15% vs 13%, P=0.51) or symptomatic intracranial haemorrhage (4% vs 2%, P=0.58). Twenty-nine percent of the thrombolysis group patients were discharged home directly, versus 6% of non-thrombolysis group (P<0.001). Mean length of stay was shorter for the thrombolysis group (25 vs 35 days; P=0.034). A similar percentage from each group was discharged to nursing homes., Conclusion: Implementation of the stroke thrombolysis service in Hong Kong appeared safe and efficacious. Patients who received thrombolysis had better outcomes compared to non-thrombolysis cohort. Further studies are needed to investigate the economics of stroke thrombolysis in Hong Kong, which may help to improve funding for provision of this service.
- Published
- 2012
21. Computed tomographic angiography for patients with acute spontaneous intracerebral hemorrhage.
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Wong GK, Siu DY, Abrigo JM, Ahuja AT, and Poon WS
- Subjects
- Humans, Sensitivity and Specificity, Cerebral Angiography, Cerebral Hemorrhage diagnostic imaging, Tomography, X-Ray Computed methods
- Abstract
With the advanced technology of multi-slice CT scans, we explored the effectiveness of CT angiography (CTA) in place of digital subtraction angiography (DSA) in patients with acute spontaneous intracerebral hemorrhage (ICH). We performed a computerized PubMed search of the literature from inception to 27 July 2011 to find reports of similar comparative studies and performed a meta-analysis of diagnostic accuracy. The pooled sensitivity was 97.0% (95% confidence interval [CI]: 93.2-99.1%), specificity was 98.9% (95% CI: 97.0-99.7%), accuracy was 98.2% (95% CI: 96.6-99.2%), positive predictive value was 97.8% (95% CI: 94.2-99.5%) and negative predictive value was 98.5% (95% CI: 96.6-99.5%). The false negative rate was 1% (95% CI: 0.4-2.6%). We concluded that CTA with venography could replace DSA as the initial vascular investigation in patients presenting with spontaneous ICH during the acute phase. Future studies should focus on whether refinement of the techniques could preclude the false negative results., (Copyright © 2011 Elsevier Ltd. All rights reserved.)
- Published
- 2012
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22. 45 year old man with a pineal region tumor for over 15 years.
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Wong YS, Chan AW, Ng HK, Chan DT, Ng DW, Siu DY, Tang P, and Poon WS
- Subjects
- Carcinoma, Papillary surgery, Diagnosis, Differential, Ependymoma classification, Humans, Male, Middle Aged, Pineal Gland surgery, Pinealoma classification, Carcinoma, Papillary pathology, Ependymoma pathology, Pineal Gland pathology, Pinealoma pathology
- Published
- 2012
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23. Association of molecular marker O(6)Methylguanine DNA methyltransferase and concomitant chemoradiotherapy with survival in Southern Chinese glioblastoma patients.
- Author
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Chan DT, Kam MK, Ma BB, Ng SC, Pang JC, Lau CK, Siu DY, Ng BS, Zhu XL, Chen GG, Ng HK, and Poon WS
- Subjects
- Asian People, Chemotherapy, Adjuvant methods, Combined Modality Therapy, Disease-Free Survival, Female, Glioblastoma drug therapy, Glioblastoma genetics, Hong Kong, Hospitals, University, Humans, Kaplan-Meier Estimate, Male, Middle Aged, Polymerase Chain Reaction, Prognosis, Retrospective Studies, Survival Rate, DNA Methylation, Glioblastoma radiotherapy, O(6)-Methylguanine-DNA Methyltransferase genetics
- Abstract
Objectives: (1) To compare the survival of concomitant chemotherapy and radiotherapy with radiotherapy alone in Chinese patients with primary glioblastoma. (2) To determine the methylation status of O(6)Methylguanine DNA methyltransferase in Chinese primary glioblastoma, and to assess the prognostic value of O(6)Methylguanine DNA methyltransferase methylation status in such patients., Design: Retrospective correlative analysis., Setting: University teaching hospital, Hong Kong., Patients: Patients diagnosed with histologically proven primary glioblastoma in the period of March 2005 to June 2007 were recruited. Genomic DNA was isolated from formalin-fixed and paraffin-embedded sections of glioblastoma tissues. Methylation-specific polymerase chain reaction for O(6)Methylguanine DNA methyltransferase was performed. Patients' information at presentation was collected (age, performance status, steroid use, extent of resection, complications, radiotherapy data, use of chemotherapy). Primary outcome was measured by overall survival while secondary outcome was measured by progression-free survival. Overall and progression-free survivals were estimated by the Kaplan-Meier technique. Outcomes were assessed for groups with and without concomitant chemoradiotherapy and for groups with and without O(6)Methylguanine DNA methyltransferase methylation., Results: A total of 35 glioblastoma patients were recruited; 27 were male and 8 female. Their mean age was 50 years. In all, 17 received concomitant chemoradiotherapy, and 18 received radiotherapy only. Their median overall survival was 12 (range, 7-17) months and the median progression-free survival was 5 (range, 3-6) months. In the radiotherapy alone group, the median progression-free survival and overall survival was 4 (range, 3-5) months and 6 (range, 2-10) months, respectively. In the concomitant radiochemotherapy group, the median progression-free survival and overall survival was 6 (range, 2-10) months and 13 (range, 8-18) months, respectively. Fifteen (43%) of the tumour samples showed methylation of O(6)Methylguanine DNA methyltransferase. There was a trend towards overall longer survival in the group with methylated tumours compared to those with unmethylated tumours; respective values for median survival (ranges) were 17 (13-21) versus 10 (6-14) months (P=0.105)., Conclusions: Our single-centre results indicated that Chinese glioblastoma patients who had received concomitant chemoradiotherapy showed a trend towards longer overall survival compared to those receiving radiotherapy alone. Approximately 43% of our Chinese glioblastoma samples showed methylation of O(6)Methylguanine DNA methyltransferase. O(6)Methylguanine DNA methyltransferase methylation may be a significant prognostic factor in Chinese glioblastoma patients.
- Published
- 2011
24. Computed tomographic angiography and venography for young or nonhypertensive patients with acute spontaneous intracerebral hemorrhage.
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Wong GK, Siu DY, Abrigo JM, Poon WS, Tsang FC, Zhu XL, Yu SC, and Ahuja AT
- Subjects
- Adolescent, Adult, Cerebral Hemorrhage etiology, Female, Humans, Intracranial Arteriovenous Malformations complications, Male, Middle Aged, Sensitivity and Specificity, Angiography, Cerebral Hemorrhage diagnostic imaging, Intracranial Arteriovenous Malformations diagnostic imaging, Tomography, X-Ray Computed
- Abstract
Background and Purpose: we compared the effectiveness of using computed tomographic angiography and venography (CTAV) with digital subtraction angiography (DSA) in young or nonhypertensive patients with acute spontaneous intracerebral hemorrhage., Methods: we prospectively recruited 109 young (age between 18 and 45 years) or nonhypertensive patients with acute spontaneous intracerebral hemorrhage for this comparative study. All patients had CTAV using multidetector CT with 64 detectors. They were then scheduled to have catheter angiography the next day. Radiological data were collected for blinded analysis., Results: DSA-positive pathologies causing hemorrhage were identified in 37 (33%) patients, which included cerebral arteriovenous malformation in 22 cases. The positive and negative predictive values of CTAV for DSA-positive pathologies causing hemorrhage were 97.3% (95% CI, 88.3%-99.9%) and 100% (95% CI, 95.9%-100%), respectively., Conclusions: CTAV was able to detect DSA-positive pathologies causing acute spontaneous intracerebral hemorrhage in young (age between 18 and 45 years) or nonhypertensive patients with high positive and negative predictive values.
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- 2011
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25. Genetic predisposition of white matter infarction with protein S deficiency and R355C mutation.
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Leung TW, Yip SF, Lam CW, Chan TL, Lam WW, Siu DY, Fan YH, Chan NP, Liu HS, Chan LC, and Wong KS
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- Adolescent, Adult, Aged, Arginine, Brain blood supply, Child, Cysteine, Female, Genetic Predisposition to Disease, Haplotypes, Hong Kong, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Molecular Sequence Annotation, Pedigree, Polymorphism, Single Nucleotide, Risk Factors, Young Adult, Brain pathology, Cerebral Infarction genetics, Cerebral Infarction pathology, Mutation, Missense, Protein S genetics, Protein S Deficiency complications
- Abstract
Background: The association between protein S deficiency (PSD) and ischemic stroke is controversial and warrants further investigation., Methods: We conducted a genotype and MRI correlation study in a Chinese family in which hereditary PSD cosegregated with premature ischemic strokes. Six out of 11 family members inherited PSD type III in an autosomal dominant manner., Results: Among all PSD members, a novel missense mutation 1063C→T in exon 10 of protein S alpha (PROS1) was identified, which encoded a substitution of arginine to cysteine at position 355 (R355C) in the first globular domain of laminin A of protein S. Wild-type PROS1 sequences were retained in non-PSD members. MRI detected deep white matter infarctions predominantly distributed in the borderzone regions. The infarct topography was homogeneous in all adult mutant carriers. By contrast, cerebral infarction was absent in nonmutant carriers. Extensive investigation in the family did not reveal any confounding stroke risk. Haplotype analysis with high-density single nucleotide polymorphism markers revealed a 6.1-Mb minimally rearranged region (rs12494685 to rs1598240) in 3q11.2, lod = 3.0. Among the 7 annotated genes in this region, PROS1 is known to be associated with thrombotic disorders. MRI screening in an additional 10 PSD families without R355C showed no cerebral infarction., Conclusions: PROS1 R355C mutation cosegregated with PSD type III and premature white matter infarctions in the index family. The findings substantiate an association between PSD and stroke. Study of the mechanism underlying this association may improve our understanding of premature cryptogenic white matter infarction.
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- 2010
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26. An expedited stroke triage pathway: the key to shortening the door-to-needle time in delivery of thrombolysis.
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Lau AY, Soo YO, Graham CA, Woo WK, Wong EH, Leung H, Chan AY, Au LW, Ip VH, Leung CS, Hui V, Shum WC, Abrigo J, Siu DY, Yu SC, Wong LK, and Leung TW
- Subjects
- Aged, Female, Humans, Male, Middle Aged, Prospective Studies, Stroke mortality, Time Management, Tissue Plasminogen Activator therapeutic use, Stroke drug therapy, Thrombolytic Therapy adverse effects, Triage
- Abstract
Objectives: To assess time management of stroke thrombolysis triage and functional outcomes in patients receiving recombinant tissue plasminogen activator for hyperacute stroke, and identify bottlenecks in delivery of the treatment., Design: Prospective study., Setting: A university teaching hospital in Hong Kong., Patients: Patients with suspected hyperacute stroke referred to the stroke thrombolysis team during October 2008 to September 2009., Main Outcome Measures: Time performance records including door-to-stroke team, door-to-needle, and onset-to-thrombolysis times. Functional outcomes by modified Rankin Scale score at 3 months, and thrombolysis-related complications including haemorrhagic transformations and mortality., Results: During the 12-month period, 95 thrombolysis calls were received; recombinant tissue plasminogen activator was given intravenously to 17 (18%) of the patients and intra-arterially to 11 (12%). The mean (standard deviation) door-to-stroke team and the door-to-needle times for intravenous recombinant tissue plasminogen activator patients were 33 (25) and 80 (25) minutes, respectively; both were about 20 minutes longer than that recommended by the National Institute of Neurological Disorders and Stroke. The mean National Institute of Health Stroke Scale score for patients received intravenous recombinant tissue plasminogen activator was 16 (standard deviation, 7). The mean (standard deviation) onset-to-treatment time was 144 (42) minutes. Nine (53%) patients who received intravenous recombinant tissue plasminogen activator achieved favourable outcomes at 3 months, with a modified Rankin Scale score of 0 to 1. Symptomatic haemorrhage and mortality occurred in one (6%) patient., Conclusion: A dedicated stroke triage pathway is essential to ensure efficient and safe delivery of thrombolysis therapy. Improvements in door-to-stroke team time through integration with emergency medicine staff and neuroradiologists may improve thrombolysis eligibility.
- Published
- 2010
27. The use of diffusion tensor tractography to measure the distance between the anterior tip of the Meyer loop and the temporal pole in a cohort from Southern China.
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Wang YX, Zhu XL, Deng M, Siu DY, Leung JC, Chan Q, Chan DT, Mak CH, and Poon WS
- Subjects
- Adult, Amygdala surgery, Anterior Temporal Lobectomy adverse effects, China, Diffusion Magnetic Resonance Imaging, Female, Hemianopsia etiology, Hemianopsia prevention & control, Hippocampus surgery, Humans, Image Processing, Computer-Assisted, Imaging, Three-Dimensional, Male, Middle Aged, Observer Variation, Temporal Lobe surgery, Young Adult, Diffusion Tensor Imaging, Optic Nerve anatomy & histology, Temporal Lobe anatomy & histology
- Abstract
Object: Anterior temporal lobe resection plus amygdalohippocampectomy can cause damage to the anterior portion of the optic radiation, also known as the Meyer loop, resulting in homonymous superior quadrantanopia. Magnetic resonance diffusion tensor tractography (DTT) of the Meyer loop can help in surgical planning. In this study, the distance of the anterior tip of the Meyer loop to the temporal lobe pole (ML-TP) in the Southern Chinese population was assessed., Methods: The authors studied 16 Southern Chinese individuals (8 men and 8 women; mean age 45.6 years, range 21-60 years). Diffusion tensor images were obtained with a 3-T MR imaging system using a single-shot spin echo echo planar imaging sequence. Two trained operators, one neurosurgeon (Operator A) and one radiologist (Operator B), carried out the DTT analysis with software iPlan (BrainLAB) and FiberTrak (Philips)., Results: For the 32 temporal lobes, the intraclass correlation coefficient (ICC) of the 2 operators' results using iPlan was 0.96, while that of Operator A using iPlan and Operator B using FiberTrak was 0.75. The ICC of Operator B using iPlan and FiberTrak was 0.81. The ML-TP distance of normal lobes (30 lobes [2 lobes that previously underwent surgery were excluded]) was 36.3±5.5 mm (range 26.6-48.9 mm), 36.3±5.3 mm (range 26.8-48.2 mm), and 35.9±6.4 mm (range 20.8-48.4 mm) for Operator A using iPlan, Operator B using iPlan, and Operator B using FiberTrak, respectively (p>0.05)., Conclusions: The 2 operators reached good agreement on ML-TP distance measurement using DTT. The DDT results can be more software dependent than operator dependent. The measurement with FiberTrak demonstrated larger range and standard deviation than measurement with iPlan.
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- 2010
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28. Comparisons of DSA and MR angiography with digital subtraction angiography in 151 patients with subacute spontaneous intracerebral hemorrhage.
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Wong GK, Siu DY, Ahuja AT, King AD, Yu SC, Zhu XL, and Poon WS
- Subjects
- Adult, Age Factors, Aged, Arteriovenous Fistula complications, Arteriovenous Fistula diagnostic imaging, Cerebral Hemorrhage etiology, Chi-Square Distribution, Female, Hong Kong, Humans, Image Processing, Computer-Assisted, Intracranial Arteriovenous Malformations complications, Intracranial Arteriovenous Malformations diagnostic imaging, Male, Middle Aged, Retrospective Studies, Angiography, Digital Subtraction methods, Cerebral Hemorrhage diagnostic imaging, Magnetic Resonance Angiography methods
- Abstract
To exclude underlying vascular abnormalities in patients with spontaneous intracerebral hemorrhage, the traditional paradigm requires investigation using digital subtraction angiography (DSA) in both the acute and subacute phases. We investigated whether MRI and magnetic resonance angiography (MRA), in the subacute stage of intracerebral hematoma, had high positive predictive values (PPV) and negative predictive values (NPV) in screening for vascular abnormality in the routine clinical setting. In a regional neurosurgical center in Hong Kong, we retrospectively reviewed 151 patients investigated with both MRI and DSA for underlying structural vascular abnormalities during the subacute phase. Sensitivity, specificity, and intermodality agreement were assessed. A total of 70/151 (46%) vascular lesions accountable for the hemorrhage were found. Patients with vascular abnormalities tended to be younger (mean age+/-standard deviation [SD], 33+/-15years), less likely to be hypertensive (6.3%), and the lesion was more likely to be accompanied by intraventricular hemorrhage (22%). In terms of cerebral arteriovenous malformation and dural arteriovenous fistulas, MRI/MRA had a PPV of 0.98 and a NPV of 1.00. We concluded that MRI/MRA was able to detect most structural vascular abnormalities in the subacute phase in most patients and, thus, its use is recommended as the screening test.
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- 2010
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29. Iatrogenic carotid-jugular fistula.
- Author
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Siu DY, Wong GK, Ho SS, Yu SC, Lam YH, and Poon WS
- Subjects
- Arteriovenous Fistula diagnostic imaging, Arteriovenous Fistula surgery, Blood Vessel Prosthesis Implantation, Carotid Artery Injuries diagnostic imaging, Carotid Artery Injuries surgery, Female, Humans, Iatrogenic Disease, Jugular Veins diagnostic imaging, Jugular Veins surgery, Kidney Failure, Chronic therapy, Middle Aged, Peritoneal Dialysis, Continuous Ambulatory, Stents, Ultrasonography, Arteriovenous Fistula etiology, Carotid Artery Injuries etiology, Catheterization, Peripheral adverse effects, Jugular Veins injuries
- Published
- 2009
30. Development of a scoring system from noncontrast computerized tomography measurements to improve the selection of upper ureteral stone for extracorporeal shock wave lithotripsy.
- Author
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Ng CF, Siu DY, Wong A, Goggins W, Chan ES, and Wong KT
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Predictive Value of Tests, Prospective Studies, Young Adult, Lithotripsy, Tomography, X-Ray Computed methods, Ureteral Calculi diagnostic imaging, Ureteral Calculi therapy
- Abstract
Purpose: We investigated the role of noncontrast computerized tomography in predicting the treatment outcome of shock wave lithotripsy on upper ureteral stones to formulate a clinical algorithm to facilitate clinical management., Materials and Methods: Adult patients with upper ureteral stones confirmed by noncontrast computerized tomography and scheduled for primary in situ shock wave lithotripsy were prospectively recruited. Standardized treatment was performed on each patient. The primary end point was stone-free status at 3 months. Pretreatment noncontrast computerized tomography was assessed by a single radiologist blinded to the clinical parameters. Predictive values of computerized tomography measurements on the treatment outcome were then assessed., Results: Between October 2004 and July 2007 a total of 94 patients (60 male and 34 female) were recruited for the study. Logistic regression showed that stone volume, mean stone density and skin-to-stone distance were potential predictors of successful treatment. From ROC curves the optimum cutoff for predicting treatment outcomes for stone volume, mean stone density and skin-to-stone distance was 0.2 cc, 593 HU and 9.2 cm, respectively. A simple scoring system was constructed based on the 3 factors of stone volume less than 0.2 cc, mean stone density less than 593 HU or skin-to-stone distance less than 9.2 cm. The stone-free rate for patients having 0, 1, 2 and 3 factors was 17.9%, 48.4%, 73.3% and 100%, respectively (linear-by-linear association test 22.83, p <0.001)., Conclusions: Stone volume, mean stone density and skin-to-stone distance were potential predictors of the successful treatment of upper ureteral stones with shock wave lithotripsy. A scoring system based on these 3 factors helps separate patients into outcome groups and facilitates treatment planning.
- Published
- 2009
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