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Chin LHQ, Cheung M, Ng GHT, Lam WWM. Kidney and Inferior Vena Cava Abnormalities with Leg Thrombosis (KILT Syndrome) in a Young Healthy Male: a Case Report. Hong Kong Journal of Radiology 2021. [DOI: 10.12809/hkjr2117261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- LHQ Chin
- Department of Radiology, Queen Mary Hospital, Hong Kong
| | - M Cheung
- Department of Radiology, Queen Mary Hospital, Hong Kong
| | - GHT Ng
- Department of Radiology, Queen Mary Hospital, Hong Kong
| | - WWM Lam
- Department of Radiology, Queen Mary Hospital, Hong Kong
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Chan VSH, Li VKS, Hui SY, Lam TPW, Lam WWM. Low-cost Self-made Phantom Model for Ultrasound-guided Breast Intervention Practice. Hong Kong Journal of Radiology 2019. [DOI: 10.12809/hkjr1917007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- VSH Chan
- Department of Radiology, Queen Mary Hospital, Pokfulam, Hong Kong
| | - VKS Li
- Department of Radiology, Queen Mary Hospital, Pokfulam, Hong Kong
| | - SY Hui
- Department of Radiology, Queen Mary Hospital, Pokfulam, Hong Kong
| | - TPW Lam
- Department of Radiology, Queen Mary Hospital, Pokfulam, Hong Kong
| | - WWM Lam
- Department of Radiology, Queen Mary Hospital, Pokfulam, Hong Kong
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Yuen VMY, Cheuk DKL, Hui TWC, Wong ICK, Lam WWM, Irwin MG. Oral chloral hydrate versus intranasal dexmedetomidine for sedation of children undergoing computed tomography: a multicentre study. Hong Kong Med J 2019; 25 Suppl 3:27-29. [PMID: 30792370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023] Open
Affiliation(s)
- V M Y Yuen
- Department of Anaesthesiology, The University of Hong Kong Shenzhen Hospital
| | - D K L Cheuk
- Department of Pediatric and Adolescent Medicine, Queen Mary Hospital
| | - T W C Hui
- Department of Anaesthesiology, Queen Mary Hospital
| | | | - W W M Lam
- Department of Anaesthesiology, The University of Hong Kong
| | - M G Irwin
- Department of Anaesthesiology, The University of Hong Kong
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Cheung KKY, Ip JK, Ko LY, Law MWM, Lam WWM. Magnetic Resonance Imaging of Neonates with Hypoxic Ischaemic Encephalopathy. Hong Kong J Radiol 2017. [DOI: 10.12809/hkjr1716399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Ng GHT, Ip JJK, Chan SHS, Ho RSL, Lam WWM. Magnetic Resonance Imaging in Mild Recessive RYR1 Gene-related Congenital Myopathies: Genetic and Histopathological Correlation. Hong Kong J Radiol 2017. [DOI: 10.12809/hkjr1715394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Kwong YY, Ip JJK, Lam WWM. Evaluation of Congenital Mitral-aortic Intervalvular Fibrosa Aneurysm: Role of Multidetector Computed Tomography in Congenital Heart Disease. Hong Kong J Radiol 2016. [DOI: 10.12809/hkjr1615314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Wong AWY, Tsang DSF, Lam WWM. How Useful is Contrast Enema in the Diagnosis of Hirschsprung’s Disease? Five-year Experience from a Local Referral Centre. Hong Kong J Radiol 2014. [DOI: 10.12809/hkjr1413206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Ip JJK, Marcet MM, Yan KW, Lam WWM, Chau MT. Congenital Fibrosis of the Extraocular Muscles: a Rare Entity. Hong Kong J Radiol 2013. [DOI: 10.12809/hkjr1311071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Ip JJK, Hui PKT, Lam SHY, Cheung SCW, Lam WWM, Chau MT. Anomalous Systemic Arterial Supply to the Normal Basal Segments of the Left Lower Lobe of the Lung. Hong Kong J Radiol 2013. [DOI: 10.12809/hkjr1312090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Kwong CYY, Ip JJK, Lam WWM, Chau MT. Magnetic Resonance Imaging for Chronic Graft-versus-host-disease–related Myositis and Fasciitis: a Rare Complication of Stem Cell Transplantation. Hong Kong J Radiol 2013. [DOI: 10.12809/hkjr1312094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Ho G, Cheung KW, Lam HL, Ip JK, Tang HYM, Lam WWM. Echogenic and Cystic Fetal Lung Lesions: Evaluation by Prenatal Sonography and Postnatal Imaging. Hong Kong J Radiol 2013. [DOI: 10.12809/hkjr1312145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Abstract
Transfusion therapy has greatly improved the survival of transfusion dependent thalassemia major (TM) patients; however, the resultant iron load damages tissues including the heart, liver and endocrine organs. Among these, heart complication still remains the leading cause of mortality. Myocardial iron deposition can occur independently of other solid organ involvement; conversely, the heart may be spared despite heavy siderosis in other tissues. Iron chelation treatment diminishes the risk of hemosiderosis; however, the chelation treatment has its own toxicities and might not be available to all patients due to costs. Close monitoring of individual organ iron concentration and function is thus important for optimization of individual patient care. This review outlines the importance and clinical significance of recently available MRI techniques for monitoring cardiac iron load.
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Affiliation(s)
- Winnie C W Chu
- Department of Imaging & Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR
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Zou WXY, Leung TW, Yu SCH, Wong EHC, Leung SF, Soo YOY, Ip VHL, Chan AYY, Lam WWM, Siu DYW, Abrigo J, Lee KT, Liebeskind DS, Wong KS. Angiographic features, collaterals, and infarct topography of symptomatic occlusive radiation vasculopathy: a case-referent study. Stroke 2013; 44:401-6. [PMID: 23306321 DOI: 10.1161/strokeaha.112.674036] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND AND PURPOSE Occlusive radiation vasculopathy (ORV) predisposes head-and-neck cancer survivors to ischemic strokes. METHODS We analyzed the digital subtraction angiography acquired in 96 patients who had first-ever transient ischemic attack or ischemic strokes attributed to ORV. Another age-matched 115 patients who had no radiotherapy but symptomatic high-grade (>70%) carotid stenoses were enrolled as referent subjects. Digital subtraction angiography was performed within 2 months from stroke onset and delineated carotid and vertebrobasilar circulations from aortic arch up to intracranial branches. Two reviewers blinded to group assignment recorded all vascular lesions, collateral status, and infarct pattern. RESULTS ORV patients had less atherosclerotic risk factors at presentation. In referent patients, high-grade stenoses were mostly focal at the proximal internal carotid artery. In contrast, high-grade ORV lesions diffusely involved the common carotid artery and internal carotid artery and were more frequently bilateral (54% versus 22%), tandem (23% versus 10%), associated with complete occlusion in one or both carotid arteries (30% versus 9%), vertebral artery (VA) steno-occlusions (28% versus 16%), and external carotid artery stenosis (19% versus 5%) (all P<0.05). With comparable rates of vascular anomaly, ORV patients showed more established collateral circulations through leptomeningeal arteries, anterior communicating artery, posterior communicating artery, suboccipital/costocervical artery, and retrograde flow in ophthalmic artery. In terms of infarct topography, the frequencies of cortical or subcortical watershed infarcts were similar in both groups. CONCLUSIONS ORV angiographic features and corresponding collaterals are distinct from atherosclerotic patterns at initial stroke presentation. Clinical decompensation, despite more extensive collateralization, may precipitate stroke in ORV.
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Affiliation(s)
- Winnie X Y Zou
- Department of Medicine and Therapeutics, Division of Neurology, Prince of Wales Hospital, Shatin, Hong Kong
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Xiong YY, Wong A, Mok VCT, Tang WK, Lam WWM, Kwok TCY, Chu WCW, Chan AYY, Wong LKS. Frequency and predictors of proxy-confirmed post-stroke cognitive complaints in lacunar stroke patients without major depression. Int J Geriatr Psychiatry 2011; 26:1144-51. [PMID: 21184437 DOI: 10.1002/gps.2652] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Accepted: 09/20/2010] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Many lacunar stroke patients complained of cognitive decline after stroke. This study aims to investigate the factors underlying post-stroke cognitive complaints in these patients. METHODS Seventy-five consecutive lacunar stroke patients without major depression were recruited for the study. Stroke severity was measured using NIHSS score and MRI was performed during the acute admission period. At 3 months, objective psychometric performance and depressive symptoms were assessed. Post-stroke cognitive complaints were corroborated by a proxy. Using logistic regression we examined the contribution of demographic features, stroke severity, objective psychometric scores, depressive symptoms, and imaging features (white matter lesion volume and infarct measures) to post-stroke cognitive complaints. RESULTS Thirty-two (42.7%) patients had post-stroke cognitive complaints. Patients with post-stroke cognitive complaints had more depressive symptoms and worse psychometric performance than those without. In the multivariate logistic regression model, only the severity of depressive symptoms was independently associated with post-stroke cognitive complaints. CONCLUSIONS This study suggests that post-stroke cognitive complaints are frequent among lacunar stroke patients without major depression and are prominently determined by the subclinical depressive symptomatology.
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Affiliation(s)
- Yun-Yun Xiong
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, New Territories Hong Kong, China
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Leung TW, Yip SF, Lam CW, Chan TL, Lam WWM, Siu DYW, Fan YH, Chan NPH, Liu HSY, Chan LC, Wong KS. Genetic predisposition of white matter infarction with protein S deficiency and R355C mutation. Neurology 2011; 75:2185-9. [PMID: 21172841 DOI: 10.1212/wnl.0b013e3182020379] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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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Affiliation(s)
- T W Leung
- Division of Neurology, Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong.
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Kirk P, He T, Anderson LJ, Roughton M, Tanner MA, Lam WWM, Au WY, Chu WCW, Chan G, Galanello R, Matta G, Fogel M, Cohen AR, Tan RS, Chen K, Ng I, Lai A, Fucharoen S, Laothamata J, Chuncharunee S, Jongjirasiri S, Firmin DN, Smith GC, Pennell DJ. International reproducibility of single breathhold T2* MR for cardiac and liver iron assessment among five thalassemia centers. J Magn Reson Imaging 2010; 32:315-9. [PMID: 20677256 DOI: 10.1002/jmri.22245] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
PURPOSE To examine the reproducibility of the single breathhold T2* technique from different scanners, after installation of standard methodology in five international centers. MATERIALS AND METHODS Up to 10 patients from each center were scanned twice locally for local interstudy reproducibility of heart and liver T2*, and then flown to a central MR facility to be rescanned on a reference scanner for intercenter reproducibility. Interobserver reproducibility for all scans was also assessed. RESULTS Of the 49 patients scanned, the intercenter reproducibility for T2* was 5.9% for the heart and 5.8% for the liver. Local interstudy reproducibility for T2* was 7.4% for the heart and 4.6% for the liver. Interobserver reproducibility for T2* was 5.4% for the heart and 4.4% for the liver. CONCLUSION These data indicate that T2* MR may be developed into a widespread test for tissue siderosis providing that well-defined and approved imaging and analysis techniques are used.
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Affiliation(s)
- Paul Kirk
- Imperial College and Royal Brompton Hospital, London, United Kingdom
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17
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Liang XC, Lam WWM, Cheung EWY, Wu AKP, Wong SJ, Cheung YF. Restrictive right ventricular physiology and right ventricular fibrosis as assessed by cardiac magnetic resonance and exercise capacity after biventricular repair of pulmonary atresia and intact ventricular septum. Clin Cardiol 2010; 33:104-10. [PMID: 20186992 DOI: 10.1002/clc.20711] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND The hypertrophic myocardium, myocardial fiber disarray, and endocardial fibroelastosis in pulmonary atresia and intact ventricular septum (PAIVS) may provide anatomic substrates for restrictive filling of the right ventricle. HYPOTHESIS Restrictive right ventricle (RV) physiology is related to RV fibrosis and exercise capacity in patients after biventricular repair of PAIVS. METHODS A total of 27 patients, age 16.5 +/- 5.6 years, were recruited after biventricular repair of PAIVS. Restrictive RV physiology was defined by the presence of antegrade diastolic pulmonary flow and RV fibrosis assessed by late gadolinium enhancement (LGE) cardiac magnetic resonance. Their RV function was compared with that of 27 healthy controls and related to RV LGE score and exercise capacity. RESULTS Compared with controls, PAIVS patients had lower tricuspid annular systolic and early diastolic velocities, RV global longitudinal systolic strain, systolic strain rate, and early and late diastolic strain rates (all P < 0.05). A total of 22 (81%, 95% confidence interval: 62%-94%) PAIVS patients demonstrated restrictive RV physiology. Compared to those without restrictive RV physiology (n = 5), these 22 patients had lower RV global systolic strain, lower RV systolic and early diastolic strain rates, higher RV LGE score, and a greater percent of predicted maximum oxygen consumption (all P < 0.05). CONCLUSION Restrictive RV physiology reflects RV diastolic dysfunction and is associated with more severe RV fibrosis but better exercise capacity in patients after biventricular repair of PAIVS.
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Affiliation(s)
- Xue-Cun Liang
- Division of Pediatric Cardiology, Department of Pediatrics and Adolescent Medicine, Queen Mary Hospital, University of Hong Kong, Hong Kong, China
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Wong A, Xiong YY, Kwan PWL, Chan AYY, Lam WWM, Wang K, Chu WCW, Nyenhuis DL, Nasreddine Z, Wong LKS, Mok VCT. The validity, reliability and clinical utility of the Hong Kong Montreal Cognitive Assessment (HK-MoCA) in patients with cerebral small vessel disease. Dement Geriatr Cogn Disord 2009; 28:81-7. [PMID: 19672065 DOI: 10.1159/000232589] [Citation(s) in RCA: 203] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/08/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS To evaluate the psychometric properties of the Hong Kong Montreal Cognitive Assessment (HK-MoCA) in patients with cerebral small vessel disease (SVD). METHODS 40 SVD patients and 40 matched controls were recruited. Concurrent and criterion validity, inter-rater and test-retest reliability, internal consistency of the HK-MoCA were examined and clinical observations were made. RESULTS Performance on the HK-MoCA was significantly predicted by both executive (beta = 0.23, p = 0.013) and non-executive (beta = 0.64, p < 0.001) composite scores. It differentiated SVD patients from controls (area under the curve = 0.81, p < 0.001) with an optimal cutoff at 21/22. Reliability, internal consistency and clinical utility were good. CONCLUSION The HK-MoCA is a useful cognitive screening instrument for use in SVD patients.
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Affiliation(s)
- Adrian Wong
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, SAR, China
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Guo H, Au WY, Cheung JS, Kim D, Jensen JH, Khong PL, Chan Q, Chan KC, Tosti C, Tang H, Brown TR, Lam WWM, Ha SY, Brittenham GM, Wu EX. Myocardial T2 quantitation in patients with iron overload at 3 Tesla. J Magn Reson Imaging 2009; 30:394-400. [PMID: 19629983 DOI: 10.1002/jmri.21851] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
PURPOSE To investigate the feasibility of measuring myocardial T2 at 3 Tesla for assessment of tissue iron in thalassemia major and other iron overloaded patients. MATERIALS AND METHODS A single-breathhold electrocardiogram-triggered black-blood multi-echo spin-echo (MESE) sequence with a turbo factor of 2 was implemented at 3 Tesla (T). Myocardial and liver T2 values were measured with three repeated breathholds in 8 normal subjects and 24 patients. Their values, together with the T2 values measured using a breathhold multi-echo gradient-echo sequence, were compared with those at 1.5T in the same patients. RESULTS At 3T, myocardial T2 was found to be 39.6 +/- 7.4 ms in normal subjects. In patients, it ranged from 12.9 to 50.1 ms. "T2 and T2(*) [corrected] were observed to correlate in heart (rho = 0.93, P [corrected] < 0.0001) and liver (rho = 0.95, P < 0.0001). Myocardial T2 and T2 at 3T were also highly correlated with the 1.5T measurements. Preliminary results indicated that myocardial T2 quantitation was relatively insensitive to B1 variation, and reproducible with 3.2% intra-exam and 3.8% inter-exam variations. CONCLUSION Myocardial T2 quantitation is feasible at 3T. Given the substantially decreased T2 and increased B0 inhomogeneity, the rapid myocardial T2 measurement protocol demonstrated here may present a robust alternative to study cardiac iron overload at 3T.
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Affiliation(s)
- Hua Guo
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
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Mok VCT, Lau AYL, Wong A, Lam WWM, Chan A, Leung H, Wong E, Soo Y, Leung T, Wong LKS. Long-term prognosis of Chinese patients with a lacunar infarct associated with small vessel disease: a five-year longitudinal study. Int J Stroke 2009; 4:81-8. [PMID: 19383047 DOI: 10.1111/j.1747-4949.2009.00262.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
RATIONALE Lacunar infarct associated with small vessel disease is a common stroke subtype in China and has a favorable short-term prognosis. Data on its long-term prognosis among Chinese patients are lacking. AIMS We aimed to study its long-term prognosis and predictors for poor outcomes. DESIGN We followed up to 75 consecutive Chinese stroke patients who had a lacunar infarct for a period of 5 years. Clinical outcomes with respect to mortality and recurrent stroke were noted. We evaluated baseline clinical and imaging predictors for such outcomes using the Cox regression analysis. STUDY OUTCOMES Sixteen (21.3%) patients died and 12 (16%) patients had recurrent stroke during follow-up. Twenty-one (28%) patients had combined events of either death and/or recurrent stroke. Univariate Cox regression analysis showed that age, literacy, National Institute of Health Stroke Scale, incident stroke/transient ischemic attack, and white matter lesion volume predicted survival, while, age, National Institute of Health Stroke Scale, systolic blood pressure, hyperhomocysteinemia, silent lacunes, microbleeds, and white matter lesion volume predicted recurrent stroke. Multivariate Cox regression analysis showed that National Institute of Health Stroke Scale (HR 1.25, 95% CI 1.05-1.48) and white matter lesion volume (HR 1.46, 95% CI 1.11-1.92) predicted combined events of mortality and/or recurrent stroke after age adjustment. CONCLUSION Approximately one in four patients either died and/or had recurrent stroke within 5 years after a lacunar infarct. Age, stroke severity, and volume of white matter lesion predict a poor long-term prognosis.
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Affiliation(s)
- Vincent C T Mok
- Department of Medicine and Therapeutics, Division of Neurology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China.
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Mok VCT, Lam WWM, Chen XY, Wong A, Ng PW, Tsoi TH, Yeung V, Liu R, Soo Y, Leung TW, Wong KS. Statins for asymptomatic middle cerebral artery stenosis: The Regression of Cerebral Artery Stenosis study. Cerebrovasc Dis 2009; 28:18-25. [PMID: 19420918 DOI: 10.1159/000215939] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2008] [Accepted: 01/21/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The progression of cerebral atherosclerosis increases the risk of stroke and vascular events. Given the known benefits of statins in retarding coronary and carotid atherosclerosis progression, we studied the effects of statins on asymptomatic middle cerebral artery (MCA) stenosis progression. METHODS We conducted a randomized, double-blind, placebo-controlled study to evaluate the effects of simvastatin on the progression of MCA stenosis among stroke-free individuals who had mild to moderately elevated LDL cholesterol (3.0-5.0 mmol/l). Two hundred and twenty-seven subjects were randomized to either placebo (n = 114) or simvastatin 20 mg daily (n = 113). The severity of MCA stenosis at baseline and at the end of the study was graded by MRA into normal, minimal (<10%), mild (10-49%), moderate (50-90%) and severe (>90%). The primary outcome was the change in grading of MCA stenosis over 2 years. RESULTS At the end of the study, the LDL cholesterol level decreased by 1.43 and 0.12 mmol/l for the active and placebo groups, respectively (p < 0.001). There was no significant difference in the proportion of patients having stable, progressive and regressive MCA stenosis between the placebo (72, 22 and 6%) and active groups (78.6, 15.5 and 5.8%). The all-cause mortality was significantly lower in the active group (n = 0) relative to the placebo group (n = 7, p = 0.014). Any clinical events were also lower in the active group (n = 5) than in the placebo group (n = 13, p = 0.052). CONCLUSIONS Simvastatin 20 mg daily had no apparent effect upon the evolution of asymptomatic MCA stenosis over 2 years.
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Affiliation(s)
- Vincent C T Mok
- Department of Medicine and Therapeutics, Chinese University of Hong Kong, Hong Kong, SAR, China.
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Au WY, Lam WWM, Chu WWC, Tam S, Wong WK, Lau J, Yeung YM, Liu HSY, Liang R. Organ-specific hemosiderosis and functional correlation in Chinese patients with thalassemia intermedia and hemoglobin H disease. Ann Hematol 2009; 88:947-50. [PMID: 19165482 DOI: 10.1007/s00277-009-0701-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2008] [Accepted: 01/13/2009] [Indexed: 01/17/2023]
Abstract
We performed MRI assessment in 37 adult Chinese patients with thalassemia intermedia and hemoglobin H disease. Despite abnormal ferritin and liver T2*, only 5% of patients had cardiac hemosiderosis. The two patients with reduced ejection fraction had normal cardiac T2*. Half of the cases showed pituitary and pancreatic iron loading. Subclinical endocrine abnormalities (HOMA, insulin growth factor) showed correlation with pancreatic, pituitary, and cardiac MRI values. Prospective data with serial functional and imaging monitoring is needed to verify the utility for chelation to improve cardiac and endocrine function in this group of patients.
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Affiliation(s)
- W Y Au
- Department of Medicine, Queen Mary Hospital, Hong Kong, Hong Kong.
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Zhang Y, Yip GW, Chan AKY, Wang M, Lam WWM, Fung JWH, Chan JYS, Sanderson JE, Yu CM. Left ventricular systolic dyssynchrony is a predictor of cardiac remodeling after myocardial infarction. Am Heart J 2008; 156:1124-32. [PMID: 19033008 DOI: 10.1016/j.ahj.2008.07.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2008] [Accepted: 07/19/2008] [Indexed: 11/17/2022]
Abstract
OBJECTIVES We sought to determine whether early assessment of left ventricular (LV) dyssynchrony by tissue Doppler imaging may predict progressive ventricular enlargement and cardiac dysfunction after acute myocardial infarction (MI). METHODS Forty-seven patients (mean age 59.9 +/- 11.6 years) with normal QRS duration underwent tissue Doppler imaging and contrast-enhanced cardiac magnetic resonance imaging (Ce-MRI) at days 2 to 6, 3 months, and at 1 year after the index MI. Systolic dyssynchrony index (Ts-SD) was calculated from 12 LV segments, and infarct size (IS) by Ce-MRI. RESULTS The remodeling group (n = 16) (defined as an increase in end-systolic volume > or =10% between 1 year and baseline) had greater initial IS (27.2 +/- 9.6 vs 13.7 +/- 4.1%, P < .001) and Ts-SD (50.9 +/- 12.8 vs 33.6 +/- 7.7 milliseconds, P < .001) than nonremodeling group (n = 31). At 1 year, the remodeling group had progressive increase in Ts-SD and decrease in LV ejection fraction (57.3 +/- 18.5 and 36.0 +/- 7.6%, respectively; both P < .05 vs baseline). Both Ts-SD (odds ratio 1.19 [1.07-1.32], P = .001) and IS (odds ratio 1.65 [1.19-2.29], P = .003) were shown to be independent predictors of progressive LV remodeling. A cutoff value of Ts-SD > or =45 milliseconds predicted LV remodeling at 1 year (sensitivity 90.5%, specificity 90.9%, Area-under-curve 0.907) (P = .0005). CONCLUSIONS Left ventricular systolic dyssynchrony is a newly identified predictor of chronic LV remodeling after acute MI, which is independent and incremental to conventional assessment and IS as measured by Ce-MRI.
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Affiliation(s)
- Yan Zhang
- Division of Cardiology, Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, PR China
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Wang YX, Lam WWM. Characterisation of brain disorders and evaluation of therapy by functional and molecular magnetic resonance techniques. Hong Kong Med J 2008; 14:469-478. [PMID: 19060347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
OBJECTIVES To review advanced functional and molecular magnetic resonance techniques that are currently clinically useful or with potential clinical use in the near future. DATA SOURCES AND EXTRACTION Literature search of Medline to December 2007 was conducted. Key words search terms were: 'magnetic resonance imaging', 'magnetic resonance spectroscopy', 'brain', 'functional', 'perfusion', 'diffusion', 'diffusion tensor', 'magnetic transfer', 'molecular imaging', 'superparamagnetic iron oxide'. Relevant original papers and review articles were retrieved. STUDY SELECTION A total of 83 original papers and review articles were systematically analysed. DATA SYNTHESIS The introduction of modern neuroimaging modalities in recent years has revolutionised investigation of the normal and diseased brain. Among others, magnetic resonance has emerged as the pre-eminent imaging modality, which can produce both high-resolution anatomical images and maps that reflect a variety of physiological parameters relevant to functional assessment and tissue characterisation. Magnetic resonance imaging techniques are now capable of visualising physiological and diseased processes at cellular and molecular levels, including cerebral blood flow, capillary perfusion and permeability, blood oxygenation level-dependent neuronal activation, microscopical motion of water (water diffusion), integrity of axonal fibres, and the molecular transfer of magnetisation within tissues. Magnetic resonance cell trafficking can evaluate the macrophage activity in areas of brain inflammation. Magnetic resonance cell-labelling strategies can be used to monitor the seeding and migration of embryonic stem cells. Magnetic resonance spectroscopy allows the detection of various metabolites that pertain to different biochemical processes in brain tissues. Such metabolites/spectra include: N-acetyl aspartate used as a neuronal marker, choline as a cell membrane metabolism marker, myo-inositol as a glial marker in proton spectrum, and phosphorous whose spectrum provides an in-vivo assessment of the bio-energetic status of tissues. Besides characterisation of brain disorders, magnetic resonance imaging and spectroscopy can improve the planning and monitoring of therapy and contribute to the development of new therapies. CONCLUSION Advances in neuroimaging have made a great leap in the morphological, metabolic, and functional assessment of the neurological diseases, enabling better diagnosis and management of patients.
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Affiliation(s)
- Y X Wang
- Department of Diagnostic Radiology and Organ Imaging, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
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Au WY, Lam WWM, Chu WWC, Tam S, Wong WK, Chan H, Law MF, Liu HSY, Liang R. A pilot MRI study of organ specific hemosiderosis and functional correlation in Chinese patients with myelodysplasia and aplastic anemia with raised ferritin levels. Hematol Oncol 2008; 26:225-228. [DOI: 10.1002/hon.862] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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Chen Y, Chen X, Mok VCT, Lam WWM, Wong KS, Tang WK. Poststroke depression in patients with small subcortical infarcts. Clin Neurol Neurosurg 2008; 111:256-60. [PMID: 19036495 DOI: 10.1016/j.clineuro.2008.10.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Revised: 09/10/2008] [Accepted: 10/11/2008] [Indexed: 11/19/2022]
Abstract
OBJECTIVES Small subcortical infarcts (SSIs) can result from small vessel disease (SVD) and intracranial and extracranial large artery disease (LAD). No study has explored poststroke depression (PSD) in different etiological types of SSIs. METHODS Patients with SSIs resulting from LAD and SVD were included in the study. Poststroke depression was evaluated with the 15-item version of the geriatric depression scale (GDS) 3 months after stroke. RESULTS Of the 127 patients with SSIs, 44 had LAD and 83 had SVD. The LAD group had a significantly higher mean GDS score and higher frequency of PSD (p<0.05). The etiological type LAD was a significant independent risk factor for PSD. CONCLUSION PSD is more common in patients with SSIs resulting from LAD. This suggests that cerebral blood perfusion may play an important role in the development of PSD.
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Affiliation(s)
- Yangkun Chen
- Department of Psychiatry, The Chinese University of Hong Kong, Hong Kong, ae, China.
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Lam WWM, Au WY, Chu WCW, Tam S, Ha SY, Pennell DJ. One-stop measurement of iron deposition in the anterior pituitary, liver, and heart in thalassemia patients. J Magn Reson Imaging 2008; 28:29-33. [PMID: 18581349 DOI: 10.1002/jmri.21433] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
PURPOSE To assess the feasibility of one-stop evaluation of iron load of myocardium, liver, and anterior pituitary gland in thalassemia patients. MATERIALS AND METHODS Fifty thalassemia major patients underwent a breath-hold magnetic resonance imaging (MRI) sequence for assessment of T2* for liver and myocardium, a short axis cine trueFISP sequence covering base to apex to assess the ejection fraction of left ventricle, and a turbo spin echo T2-weighted sequence for the anterior pituitary gland. The MRI parameters were correlated with serum growth hormone, insulin growth factor-1 (IGF-1), insulin growth factor binding protein-3 (IGFBP-3), and endocrine failure. RESULTS Ferritin was found to be associated with T2* liver (P < 0.005), T2SI (signal intensity) pituitary (P = 0.001), and T2 pituitary/fat (P = 0.001), but not with T2* heart. There was significant correlation of T2SI pituitary with IGF-1 and IGFBP-3. T2* liver (P < 0.001), T2* heart (P < 0.001), pituitary SI (P < 0.001) and pituitary/fat SI (P = 0.002) were also found to be significantly correlated with a history of hypogonadism. T2* heart was also found to be significantly correlated with IGF-1. CONCLUSION A quick MRI protocol for assessment of T2* liver, T2* heart, and T2SI pituitary is technically feasible. This might form an objective basis to monitor the response to different organs to chelation therapy.
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Affiliation(s)
- Wynnie W M Lam
- Department of Diagnostic Radiology and Organ Imaging, Chinese University of Hong Kong, Prince of Wales Hospital, 30-32 Ngan Shing Street, Hong Kong SAR.
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Leung TW, Yu SCH, Lam WWM, Wong LKS. The NIH registry on use of the Wingspan stent for symptomatic 70-99% intracranial arterial stenosis. Neurology 2008; 71:1124; author reply 1124-5. [PMID: 18824679 DOI: 10.1212/01.wnl.000032353.550765.3c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Liu T, Chu WCW, Young G, Li K, Yeung BHY, Guo L, Man GCW, Lam WWM, Wong STC, Cheng JCY. MR analysis of regional brain volume in adolescent idiopathic scoliosis: neurological manifestation of a systemic disease. J Magn Reson Imaging 2008; 27:732-6. [PMID: 18302230 DOI: 10.1002/jmri.21321] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To investigate whether regional brain volumes in adolescent idiopathic scoliosis (AIS) patients differ from matched control subjects as AIS subjects are reported to have poor performance on combined visual and proprioceptive testing and impaired postural balance in previous studies. MATERIALS AND METHODS Twenty AIS female patients with typical right-convex thoracic curve (age range,11-18 years; mean, 14.1 years) and 26 female controls (mean age, 14.8 years) underwent three-dimensional magnetization prepared rapid acquisition gradient echo (3D-MPRAGE) MR imaging. Volumes of 99 preselected neuroanatomical regions were compared by statistical parametric mapping and atlas-based hybrid warping. RESULTS Analysis of variance statistics revealed significant mean volumetric differences in 22 brain regions between AIS and controls. Ten regions were larger in AIS including the left frontal gyri and white matter in left frontal, parietal, and temporal regions, corpus callosum and brainstem. Twelve regions were smaller in AIS, including right-sided descending white matter tracts (anterior and posterior limbs of the right internal capsule and the cerebral peduncle) and deep nucleus (caudate), bilateral perirhinal cortices, left hippocampus and amygdala, bilateral precuneus gyri, and left middle and inferior occipital gyri. CONCLUSION Regional brain volume difference in AIS subjects may help to explain neurological abnormalities in this group.
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Affiliation(s)
- Tianming Liu
- Functional and Molecular Imaging Center, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Tse GMK, Ma TKF, Lui PCW, Ng DCH, Yu AMC, Vong JSL, Niu Y, Chaiwun B, Lam WWM, Tan PH. Fine needle aspiration cytology of papillary lesions of the breast: how accurate is the diagnosis? J Clin Pathol 2008; 61:945-9. [DOI: 10.1136/jcp.2008.057489] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Chow PC, Liang XC, Cheung EWY, Lam WWM, Cheung YF. New two-dimensional global longitudinal strain and strain rate imaging for assessment of systemic right ventricular function. Heart 2008; 94:855-9. [DOI: 10.1136/hrt.2007.131862] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Leung TW, Lam WWM, Yu SCH, Leung CSF, Soo YOY, Wong LKS. Multimodal computed tomography evaluation before thrombolysis in acute ischaemic stroke. Hong Kong Med J 2008; 14:236-239. [PMID: 18525096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Abstract
Currently, when stroke patients are offered thrombolytic therapy, their ischaemic stroke subtypes are usually unknown. Given the risk of haemorrhage that accompanies thrombolytic therapy, unselective (or undiscriminating) use of recombinant tissue plasminogen activator in patients without large-artery thromboemboli is potentially hazardous. Advances in computed tomography techniques have enabled the stroke pathophysiology to be quickly delineated by multimodal computed tomography without compromise in time for recombinant tissue plasminogen activator administration. Through description of the investigation of a typical stroke patient, we report how this technique is feasible in a regional hospital and may guide judicious use of recombinant tissue plasminogen activator.
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Affiliation(s)
- Thomas W Leung
- Division of Neurology, Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong
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Lam WWM, Chan CP, Chan CF, Mak CCC, Chan CF, Chong KWH, Leung MHJ, Tang MH. Factors affecting the palpability of breast lesion by self-examination. Singapore Med J 2008; 49:228-232. [PMID: 18363005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
INTRODUCTION This study aims to assess the accuracy of detection of breast lesion by breast self-examination and to assess different factors affecting the accuracy. METHODS All consecutive Chinese female patients, who attended our breast imaging unit in 2001, completed our questionnaire, had retrievable hard copy films, and had more than three years clinical follow-up, were recruited for this study. Different factors, such as age, menopausal status, previous experience of breastfeeding, family history of breast cancer, previous history of mastectomy or lumpectomy, hormonal therapy, oral contraceptive pills and previous history of mammography, were correlated with accuracy in self-detection of breast lesions retrospectively. The nature, size and location of the lesion, and breast size based on imaging, were also correlated with the accuracy in self-detection of breast lesions. RESULTS A total of 163 questionnaires were analysed. 111 patients detected a breast lesion themselves and 24 of these lesions were false-positives. A total of 173 lesions (27 cancerous, 146 benign lesions) were documented by either ultrasonography and/or mammography, and confirmed by either histology or three-year clinical follow-up. The overall sensitivity in detecting both benign and malignant breast lesions was 71% when number of breast lesions was used as the denominator, and up to 78% sensitivity was achieved when number of patients was used as the denominator. History of mastectomy, and size and nature of the lesions were found to affect the accuracy of self-detection of breast lesions. CONCLUSION Overall, breast self-examinations were effective in the detection of breast lesions and factors such as size of lesion, nature of the lesion and history of mastectomy affect the accuracy of the detections. Breast self-examination should be promoted for early detection of breast cancer.
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Affiliation(s)
- W W M Lam
- Department of Diagnostic Radiology and Organ Imaging, The Chinese University of Hong Kong, 30-32 Ngan Shing Street, Shatin, Hong Kong SAR.
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Mok VCT, Liu T, Lam WWM, Wong A, Hu X, Guo L, Chen XY, Tang WK, Wong KS, Wong S. Neuroimaging predictors of cognitive impairment in confluent white matter lesion: volumetric analyses of 99 brain regions. Dement Geriatr Cogn Disord 2008; 25:67-73. [PMID: 18042992 DOI: 10.1159/000111692] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/05/2007] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Although confluent white matter lesion (WML) is associated with cognitive impairment, the mechanism explaining this association is controversial. We aimed to investigate comprehensively the MRI predictors of cognitive impairment in confluent WML. METHODS Among 45 lacunar stroke patients who had confluent WML, we evaluated the association of executive function [Mattis Dementia Rating Scale - Initiation/Perseveration subscale (MDRS I/P)] and global cognition [Mini-Mental State Examination (MMSE)] with the volume of WML, measures of lacunes and microbleeds, and the volumes of 99 other specific brain regions. RESULTS Regression analyses showed that WML volume predicted performance on the MDRS I/P (beta = -0.34, p = 0.016) independent of age. Volumes of cortical gray matter (cGM; beta = 0.41, p = 0.003), the lateral fronto-orbital gyrus (beta = 0.38, p = 0.01), superior frontal gyrus (beta = 0.29, p = 0.04), lateral ventricle (beta = -0.30, p = 0.04), and posterior limb of the internal capsule (beta = 0.43, p = 0.002) predicted MDRS I/P performance independent of WML volume. Volumes of cGM, and the lateral fronto-orbital gyrus predicted MMSE performance as well. CONCLUSION Atrophy along the frontosubcortical pathways and cGM predict cognition in confluent WML independent of WML volume.
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Affiliation(s)
- Vincent C T Mok
- Department of Medicine and Therapeutics, Chinese University of Hong Kong, Shatin, Hong Kong, SAR, China.
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Abstract
BACKGROUND We explored the efficacy and tolerability of rivastigmine among Chinese patients with subcortical vascular dementia. METHODS Forty subjects were randomized to either placebo (n = 20) or rivastigmine (n = 20) in a double-blind 26-week trial. Outcome measures were cognition (mini-mental state examination, frontal assessment battery), neuropsychiatric inventory (NPI), instrumental activities of daily living, clinical dementia rating scale, and adverse events. RESULTS No statistical significant benefit could be observed in the active group in any of the efficacy measures. A trend favoring active group was observed only in the NPI subscore of irritability (p = 0.066) and aberrant motor behavior (p = 0.068). Withdrawal rate was 30% and 15% in the active and placebo group, respectively. CONCLUSION Among Chinese subcortical vascular dementia patients, there was no apparent cognitive benefit associated with use of rivastigmine over the 6 months period. A trend favoring rivastigmine was observed in certain behavioral measures. Rivastigmine was associated with more withdrawals relative to placebo.
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Affiliation(s)
- Vincent Mok
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong, China.
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Abstract
The study is to determine the optimal MRI bowel preparation regime for visualization of the stomach anatomy. Eight healthy volunteers were asked to take water, 75% barium and blueberry juice. The image quality and tolerance of different stomach distension regime were evaluated. Blueberry juice gave the best distension, but the signal intensity was not very homogeneous. Taking into account the image quality, tolerability and adverse effects, it is concluded that water is the most desirable oral contrast for MR stomach imaging.
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Affiliation(s)
- W W M Lam
- Department of Diagnostic Radiology and Organ Imaging, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR.
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Tse GM, Tan PH, Cheung HS, Chu WCW, Lam WWM. Intermediate to highly suspicious calcification in breast lesions: a radio-pathologic correlation. Breast Cancer Res Treat 2007; 110:1-7. [PMID: 17674189 DOI: 10.1007/s10549-007-9695-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2007] [Accepted: 07/16/2007] [Indexed: 02/07/2023]
Abstract
Breast calcification is an important feature in the radiological assessment of breast lesions. There are well established diagnostic criteria basing on the morphology and distribution of the calcifications radiologically with recommendation protocols. Pathologically, calcifications in breast lesions are of dystrophic type, and may occur in either the secretory materials or necrotic debris, with inflammation and osteopontin being plausible mediators. Detection of calcium phosphate (hydroyapaptite) is considerably easier than calcium oxalate. Radiologically amorphous calcification represents a borderline type of calcification, and occurs in both benign and malignant (low grade) lesions, and warrants careful follow up and investigation. Clustering of calcification alone may not be an accurate predictor for malignancy, but when there are associated features like pleomorphism, branching, architectural distortion, and associated mass or density, the predictive value for malignant increases. Adequate sampling of calcification in the biopsy is crucial in the management of patients; in general, needle core biopsy or mammotome biopsy achieve satisfactory calcification retrieval. In a benign biopsy that fails to identify the calcifications visible in the mammography, further evaluation or cutting of the histologic block is recommended to minimize the potential of a false negative investigation.
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Affiliation(s)
- Gary M Tse
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Ngan Shing Street, Shatin, NT, Hong Kong SAR.
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Chu WCW, Man GCW, Lam WWM, Yeung BHY, Chau WW, Ng BKW, Lam TP, Lee KM, Cheng JCY. A detailed morphologic and functional magnetic resonance imaging study of the craniocervical junction in adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 2007; 32:1667-74. [PMID: 17621216 DOI: 10.1097/brs.0b013e318074d539] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Conventional and phase-contrast magnetic resonance (MR) imaging were used to evaluate the morphology and cerebrospinal fluid (CSF) flow dynamics at craniocervical junction in adolescent idiopathic scoliosis (AIS). OBJECTIVES To determine the morphology of cerebellar tonsil, foramen magnum, and dynamic flow of CSF at the craniocervical junction in AIS patients versus normal controls and their correlation with somatosensory cortical evoked potentials (SSEP). SUMMARY OF BACKGROUND DATA Previous studies have documented obstructed CSF flow in patients with Chiari I malformation. Low-lying cerebellar tonsils and syringomyelia are also observed in AIS patients. We sought to investigate whether disturbed CSF flow is also evident in AIS subjects at the foramen magnum level and its association with level of cerebellar tonsils and dimensions of foramen magnum. METHODS Conventional and phase-contrast MR were performed in 105 adolescent girls (69 AIS subjects and 36 age-matched controls). Measurements of cerebellar tonsillar level related to the basion-opsithion (BO) line, anteroposterior (AP), transverse (TS) diameter, and area of foramen magnum, and peak velocity of CSF flow in both the anterior and posterior subarachnoid space through foramen magnum were obtained. Correlations were made among different parameters and SSEP findings. RESULTS A total of 42% of subjects in the AIS group had the cerebellar tonsillar tip positioned 1 mm below the BO line. The cerebellar tonsillar level in AIS subjects was significantly lower than the median tonsillar level in normal controls (P < 0.01). The AP diameter and area of foramen magnum were significantly larger in AIS subjects when compared with normal controls (P < 0.05), but the peak CSF velocities through foramen magnum showed no significant difference (P > 0.05). CONCLUSION Peak CSF velocities through foramen magnum were not significantly different in AIS subjects despite the presence of low-lying cerebellar tonsils. This might be explained by the compensatory effect of larger foramen magnum in AIS subjects.
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Affiliation(s)
- Winnie C W Chu
- Department of Diagnostic Radiology and Organ Imaging, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
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Chu WCW, Tam YH, Lam WWM, Ng AWH, Sit F, Yeung CK. Dynamic MR assessment of the anorectal angle and puborectalis muscle in pediatric patients with anismus: technique and feasibility. J Magn Reson Imaging 2007; 25:1067-72. [PMID: 17410575 DOI: 10.1002/jmri.20914] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
PURPOSE To assess the feasibility of dynamic breath-hold MRI for evaluating changes in the anorectal angle and movements of the pelvic-floor musculature (puborectalis) during resting and straining states in pediatric patients presenting with anismus. MATERIALS AND METHODS Six pediatric patients (7-13 years old) with chronic constipation and manometric evidence of anismus were assessed by dynamic breath-hold MRI. Changes in the anorectal angle, the degree of pelvic-floor descent, and the thickness and length of the puborectalis muscles were measured during rest and straining. The findings were compared with those obtained in six age- and sex-matched controls. RESULTS The children with anismus had a smaller anorectal angle during straining, and the angle decreased from rest to defecation. The puborectalis also became paradoxically shortened and thickened during straining in the anismus group. There were significant differences between the two groups in terms of the change of degree of the anorectal angle, and the thickness and length of the puborectalis muscle during straining. CONCLUSION Fast dynamic MRI is feasible for evaluating pelvic-floor movement in pediatric patients. Preliminary results suggest that children with anismus have a smaller anorectal angle and a different puborectalis configuration compared to controls.
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Affiliation(s)
- Winnie C W Chu
- Department of Diagnostic Radiology and Organ Imaging, Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR, China.
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Wong A, Mok VCT, Tang WK, Lam WWM, Wong KS. Comparing Mattis Dementia Rating Scale--initiation/perseveration subset and frontal assessment battery in stroke associated with small vessel disease. J Clin Exp Neuropsychol 2007; 29:160-9. [PMID: 17365251 DOI: 10.1080/13803390600582453] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Forty-two controls and 32 patients with stroke associated with small vessel disease (SSVD) were administered the Mattis Dementia Rating Scale Initiation / Perseveration subset (MDRS I/P) and Frontal Assessment Battery (FAB). Both tests showed comparably good ability in Receiver Operating Characteristics curves analysis (AUCMDRS I/P=0.887; AUC FAB=0.854, p=.833) in discriminating between controls and patients and correctly classified over 78% of subjects. Verbal fluency and motor programming contributed most to the discriminating power in the two tests. The MDRS I/P and FAB are useful in discriminating between controls and SSVD patients in a hospital setting.
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Affiliation(s)
- Adrian Wong
- Department of Medicine and Therapeutics, Chinese University of Hong Kong, Hong Kong
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Han JH, Ho SSY, Lam WWM, Wong KS. Total cerebral blood flow estimated by color velocity imaging quantification ultrasound: a predictor for recurrent stroke? J Cereb Blood Flow Metab 2007; 27:850-6. [PMID: 16985507 DOI: 10.1038/sj.jcbfm.9600392] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Although the Virchow's triad on thrombosis includes reduced blood flow as a factor, there has been relatively little data on the importance of total cerebral blood flow on the risk of subsequent stroke. In the current study, we investigate whether total cerebral blood flow helps predict stroke recurrence. Extracranial arterial blood flow volume estimated by color velocity imaging quantification ultrasound (CVIQ) is an index of cerebral blood flow measurement. We performed a cohort study of 210 consecutive acute stroke patients. Patients were studied with transcranial Doppler and duplex ultrasound for intra- and extracranial large artery disease within 3 days of symptom onset. The association between the risk of recurrent stroke and CVIQ was analyzed with Cox proportional hazards model. Thirty-nine patients (17.7%) developed an ischemic stroke during a mean follow-up of 47.5 months. The mean extracranial blood flow volume was significantly lower for patients who had a recurrent stroke than those without (594.4+/-130.3 versus 683.8+/-176.9 mL/min; P=0.003). In a Cox proportional hazards model adjusting for potential confounding variables, extracranial blood flow volume (hazard ratio (HR) for lowest tertile, 4.1; 95% confidence interval (CI), 1.5 to 11.0) along with male sex (HR, 2.5; 95% CI, 1.3 to 5.1), diabetes (HR, 2.5; 95% CI, 1.2 to 5.0) and large artery stenosis (HR, 2.2; 95% CI, 1.1 to 4.4) were independent predictors for stroke recurrence. Our data indicated that patient with low amount of blood flow to the brain is at risk of recurrent stroke.
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Affiliation(s)
- Jing Hao Han
- Department of Medicine & Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
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King AD, Ahuja AT, Yeung DK, Wong JKT, Lee YYP, Lam WWM, Ho SSM, Yu SCH, Leung SF. Delayed complications of radiotherapy treatment for nasopharyngeal carcinoma: imaging findings. Clin Radiol 2007; 62:195-203. [PMID: 17293211 DOI: 10.1016/j.crad.2006.10.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2006] [Revised: 09/29/2006] [Accepted: 10/03/2006] [Indexed: 11/20/2022]
Abstract
Radiotherapy is used to treat a wide variety of head and neck tumours that arise in and around the skull base. The delayed effects of radiation damages a range of structures, including the nervous system, bone, major vessels, mucus membranes, pituitary and salivary glands, as well as increasing the risk of radiation-induced neoplasms. In this review the complications resulting from radiation treatment for nasopharyngeal carcinoma (NPC), a cancer treated with a high dose of radiation to a fairly large region, are illustrated. Many patients with NPC have a long-term survival, so are at risk of developing delayed radiation effects, and hence may demonstrate a wide range of complications on imaging. Other tumours around the skull base treated with radiotherapy include meningiomas, chordomas, chondrosarcomas, pituitary adenomas, paranasal sinus and nasal cavity tumours. In these cases similar complications may be encountered on imaging, although the severity, incidence and location will vary.
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Affiliation(s)
- A D King
- Department of Diagnostic Radiology and Organ Imaging, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong, S.A.R., China.
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Ka-Tak W, Lam WWM, Yu SCH. MDCT of an Aberrant Right Subclavian Artery and of Bilateral Vertebral Arteries with Anomalous Origins. AJR Am J Roentgenol 2007; 188:W274-5. [PMID: 17312035 DOI: 10.2214/ajr.05.0694] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Wong Ka-Tak
- Department of Diagnostic Radiology & Organ Imaging, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, SAR.
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Wong TYY, Lam WWM, Lau TK. Foetal magnetic resonance imaging. Hong Kong Med J 2006; 12:486-7. [PMID: 17148808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023] Open
Affiliation(s)
- T Y Y Wong
- Department of Diagnostic Radiology and Organ Imaging, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong
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Chu WCW, Mok GCF, Lam WWM, Yam MC, Sung RYT. Assessment of coronary artery aneurysms in paediatric patients with Kawasaki disease by multidetector row CT angiography: feasibility and comparison with 2D echocardiography. Pediatr Radiol 2006; 36:1148-53. [PMID: 16912893 DOI: 10.1007/s00247-006-0281-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2006] [Revised: 06/28/2006] [Accepted: 07/02/2006] [Indexed: 10/24/2022]
Abstract
BACKGROUND Transthoracic ECHO is the locally accepted method for coronary surveillance of patients with Kawasaki disease but it may have limited visualization in the older child. OBJECTIVE To assess the feasibility of multidetector CT (MDCT) angiography in the follow-up of coronary artery aneurysms in children with previous Kawasaki disease. MATERIALS AND METHODS Six children (5 boys, 1 girl; mean age 11.5 years) with known Kawasaki disease and coronary artery involvement underwent CT coronary angiography using 16-detector MDCT. The visualized lengths and diameter of all coronary segments were measured. The number, size and location of coronary artery aneurysms were recorded and compared with recent ECHO. RESULTS Twelve coronary artery aneurysms (seven saccular, five fusiform) were identified by MDCT angiography. One saccular aneurysm at the junction of the distal right coronary artery and posterior descending artery was not detected by ECHO while the remaining six in proximal segments were detected by both modalities. Two of five fusiform aneurysms were not detected by ECHO due to their small sizes. Excellent agreement was found between CT and ECHO for maximal diameter and length of the visualized aneurysms. CONCLUSIONS MDCT angiography accurately defines coronary artery aneurysms. It is more sensitive for detecting aneurysms at distal coronary segments and fusiform aneurysms of small size.
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Affiliation(s)
- Winnie C W Chu
- Department of Diagnostic Radiology and Organ Imaging, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Ngan Shing Street, Shatin, New Territories, Hong Kong,
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Wen HM, Baum L, Cheung WS, Mok V, Lam WWM, Tomlinson B, Wong KS, Ng HK. Apolipoprotein E ?4 allele is associated with the volume of white matter changes in patients with lacunar infarcts. Eur J Neurol 2006; 13:1216-20. [PMID: 17038035 DOI: 10.1111/j.1468-1331.2006.01436.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The relationship between the apolipoprotein E (APOE) exon 4 polymorphism and white matter changes (WMC) in elderly subjects or patients with Alzheimer's disease is controversial. To investigate this polymorphism in relation to WMC in patients with lacunar infarcts, we prospectively observed 67 patients with acute lacunar infarct and 134 age- and sex-matched controls. Genotypes were determined using a nested polymerase chain reaction. WMC were measured quantitatively and were divided into two groups, severe and mild, with the mean volume of WMC as the cut point. Twenty-two patients (33%) had severe WMC. There was a significant difference in the distribution of APOE epsilon2, epsilon3, and epsilon4 alleles between severe and mild WMC groups (P = 0.002). The frequency of epsilon4 alleles was higher in patients with severe WMC than in those with mild WMC (25% vs. 7%, P = 0.003). These results suggest that APOE epsilon4 may exacerbate WMC in patients with lacunar infarcts. Further studies are required to confirm this finding.
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Affiliation(s)
- H M Wen
- Department of Rehabilitation, the third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
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Chu WCW, Li AM, Ng BKW, Chan DFY, Lam TP, Lam WWM, Cheng JCY. Dynamic magnetic resonance imaging in assessing lung volumes, chest wall, and diaphragm motions in adolescent idiopathic scoliosis versus normal controls. Spine (Phila Pa 1976) 2006; 31:2243-9. [PMID: 16946662 DOI: 10.1097/01.brs.0000232822.74349.32] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Dynamic breath-hold (BH)- magnetic resonance (MR) imaging was used to evaluate lung function in adolescent idiopathic scoliosis (AIS). OBJECTIVES Changes in lung volume, chest wall, and diaphragmatic motions were evaluated in AIS patients and compared with normal controls. SUMMARY OF BACKGROUND DATA Little is known about whether pulmonary function impairment in AIS is related to restriction of lung volume, poor chest wall expansibility, or impaired diaphragmatic motion. This is a study on the underlying pathophysiology of the abnormal pulmonary function in AIS using the ultrafast BH-MR imaging technique. METHODS Forty-two patients with moderate to severe right thoracic scoliosis (Cobb angle, 40 degrees -98 degrees), 22 patients with mild right thoracic scoliosis (Cobb angle 10 degrees -30 degrees), and 12 healthy subjects (age ranged, 11-18 years; all girls) were recruited for the following assessments: 1) inspiratory, expiratory, and change in lung volume; 2) change in anteroposterior (AP) and transverse (TS) diameter of the chest wall at two levels: carina and apical vertebra level; and 3) change in diaphragmatic heights. RESULTS Inspiratory, expiratory lung volume and diaphragmatic heights were significantly reduced in the severe scoliosis group (P < 0.05), but the change in lung volume was not affected. There was no significant difference in the change of AP or TS diameter of the chest wall as well as diaphragmatic motions among groups. CONCLUSION Impairment in lung function in AIS patients is predominantly due to restriction of lung volume.
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Affiliation(s)
- Winnie C W Chu
- Department of Diagnostic Radiology, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
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Chu WCW, Wong MS, Chau WW, Lam TP, Ng KW, Lam WWM, Cheng JCY. Curve correction effect of rigid spinal orthosis in different recumbent positions in adolescent idiopathic scoliosis (AIS): a pilot MRI study. Prosthet Orthot Int 2006; 30:136-44. [PMID: 16990224 DOI: 10.1080/03093640600578020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In this pilot cross-sectional study, the effectiveness of rigid spinal orthoses in the correction of spinal curvature of 14 patients with moderate adolescent idiopathic scoliosis (AIS) at different recumbent positions (supine, prone, right and left decubitus) was investigated. Using magnetic resonance (MR) imaging and multi-planar reconstruction technique, evaluation of the scoliotic spine in the coronal, sagittal and axial planes and the effect of spinal orthosis on AIS at different recumbent positions was studied. There was significant reduction of coronal Cobb's angle (p < 0.05) with bracing at all four recumbent positions and the maximal reduction was found in the prone position (18% reduction). The sagittal Cobb's angle was only significantly reduced at the supine position while the axial rotation did not change significantly in all positions.
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Affiliation(s)
- W C W Chu
- The Chinese University of Hong Kong, Department of Diagnostic Radiology and Organ Imaging, Prince of Wales Hospital, Shatin, Hong Kong, PR China.
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Wang X, Lam WWM, Fan YH, Graham CA, Rainer TH, Wong KS. Topographic Patterns of Small Subcortical Infarcts Associated with MCA Stenosis: A Diffusion-Weighted MRI Study. J Neuroimaging 2006; 16:266-71. [PMID: 16808829 DOI: 10.1111/j.1552-6569.2006.00027.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE Small subcortical infarcts (SSI, maximum lesion diameter < or =2.0 cm) are usually considered as infarcts caused by small vessel disease. However, SSI can also be associated with large artery occlusive disease such as middle cerebral artery (MCA) stenosis. We performed a prospective study to investigate the relationship between MCA stenosis and SSI distribution and further to investigate the mechanism of SSI caused by MCA stenosis. METHODS Magnetic resonance angiography (MRA) and diffusion-weighed MRI (DWI) of consecutive acute ischemic stroke patients with recent SSI were studied. The distribution of acute infarcts on DWI was categorized as cortical infarct (CI), border zone infarct (BI), or perforating artery infarct (PAI). RESULTS Totally, 93 cases were recruited, among which 12 had single SSI with MCA stenosis (group 1) and 26 patients had multiple SSI with MCA stenosis (group 2), while 55 patients without MCA stenosis had single SSI (group 3). For patients with single SSI and MCA stenosis, 6 had BI and 6 had PAI; for patients with multiple SSI and MCA stenosis, 25 had BI, 4 had PAI and 9 had CI (compared with group 1: P= .001); for patients with single SSI but without MCA stenosis, 20 had BI and 35 had PAI (compared with group 1: P= .58). CONCLUSION Multiple acute infarcts along the border zone are the commonest pattern in small infarcts with MCA stenosis, especially among those with multiple acute infarcts. Our data suggest that hemodynamic compromise and artery-to-artery embolism may be both important factors for infarcts in patients with MCA stenosis.
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Affiliation(s)
- Xin Wang
- Department of Medicine and Therapeutics, Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
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Chu WCW, Li AM, Ng AWH, So HK, Lam WWM, Lo KL, Yeung MCA, Yau YS, Chiu WK, Leung CW, Ng PC, Hon KL, Mo KW, Fok TF, Ahuja AT. Thin-Section CT 12 Months After the Diagnosis of Severe Acute Respiratory Syndrome in Pediatric Patients. AJR Am J Roentgenol 2006; 186:1707-14. [PMID: 16714663 DOI: 10.2214/ajr.05.0382] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
OBJECTIVE The objective of our study was to report the thin-section CT findings 12 months after the diagnosis of severe acute respiratory syndrome (SARS) in pediatric patients who had recovered clinically but had persistent abnormal CT findings 6 months after the diagnosis. The clinical data for these patients were correlated to identify risk factors that might increase the likelihood of the development of CT abnormalities. SUBJECTS AND METHODS The study involved an extended 12-month thin-section CT follow-up of 16 of 47 pediatrics patients with SARS coronavirus-associated pneumonia proven serologically (21 girls and 26 boys; age range, 1.5-17 years; median age, 13.6 years). Patients' clinical information, the extent of radiographic opacification during the acute phase of illness, and conventional pulmonary function test results on follow-up were obtained for correlation. The clinical parameters were compared with other pediatric SARS patients who had normal CT findings at the 6-month follow-up. RESULTS Fifteen patients still had abnormal CT findings 12 months after diagnosis, all of whom were older than 10 years (age range, 10-17 years). In seven patients with previous residual ground-glass opacification at the 6-month follow-up, two showed persistent changes and three had a reticular pattern in the area of the previously detected abnormality, whereas two showed complete resolution. The extent of air trapping remained similar to that at the 6-month follow-up in nine of 11 patients while two showed a slight increase in the same segments. Parenchymal scars remained unchanged from the 6- to 12-month follow-up in all six patients with that finding. None of our patients showed any evidence of bronchiectasis or bronchial wall thickening. Lymphopenia (p = 0.03), extent of radiographic opacification at acute illness (p = 0.047), and duration of use of ribavirin (p = 0.03) were significant risk factors in predicting whether abnormal CT features persisted 12 months after diagnosis. CONCLUSION We found that 32% of the children (15/47) affected with SARS showed thin-section CT abnormalities up to 12 months after diagnosis despite clinical remission and unremarkable pulmonary function assessment. Persistent CT abnormalities are more likely to develop in patients who are older and who present with more severe disease. The CT changes in children with SARS are, however, minor.
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Affiliation(s)
- Winnie C W Chu
- Department of Diagnostic Radiology and Organ Imaging, The Chinese University of Hong Kong, Prince of Wales Hospital, Ngan Shing St., Shatin, Hong Kong SAR, China
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