The Association Between Clinical Parameters And Glaucoma-specific Quality Of Life In Chinese Primary Open-angle Glaucoma Patients

Objective: To investigate the association between clinical measurements and glaucoma-specific quality of life in Chinese glaucoma patients. Design: Cross-sectional study. Setting: An academic hospital in Hong Kong. Patients: A Chinese translation of the Glaucoma Quality of Life–15 questionnaire was completed by 51 consecutive patients with bilateral primary open-angle glaucoma. The binocular means of several clinical measurements were correlated with Glaucoma Quality of Life–15 findings using Pearson’s correlation coefficient and linear regression. The measurements were the visual field index and pattern standard deviation from the Humphrey Field Analyzer, Snellen best-corrected visual acuity, presenting intra-ocular pressure, current intra-ocular pressure, average retinal nerve fibre layer thickness via optical coherence tomography, and the number of topical anti-glaucoma medications being used. Results: In these patients, there was a significant correlation and linear relationship between a poorer Glaucoma Quality of Life–15 score and a lower visual field index (r=0.3, r2=0.1, P=0.01) and visual acuity (r=0.3, r2=0.1, P=0.03). A thinner retinal nerve fibre layer also correlated with a poorer Glaucoma Quality of Life–15 score, but did not attain statistical significance (r=0.3, P=0.07). There were no statistically significant correlations for the other clinical parameters with the Glaucoma Quality of Life–15 scores (all P values being >0.7). The three most problematic activities affecting quality of life were “adjusting to bright lights”, “going from a light to a dark room or vice versa”, and “seeing at night”. Conclusion: For Chinese primary open-angle glaucoma patients, binocular visual field index and visual acuity correlated linearly with glaucoma- specific quality of life, and activities involving dark adaptation were the most problematic.published_or_final_versio

Development of a Chinese version of the National Eye Institute Visual Function Questionnaire (CHI-VFQ-25) as a tool to study patients with eye diseases in Hong Kong

Background: To develop a Chinese version of the National Eye Institute Visual Function Questionnaire (CHI-VFQ-25) and to test its reliability and validity in a group of patients with eye diseases in Hong Kong. Methods: The National Eye Institute Visual Function Questionnaire (NEI-VFQ) was translated into Chinese. Patients were recruited from Hong Kong, and their demographic data and visual acuity were documented. Psychometric properties of the CHI-VFQ-25, including internal consistency, test-retest reliability, item-scale correlations and construct validity were tested. Results: 250 patients were recruited. The mean age of the patients was 66.04 (SD 14.00). 46% of them were male. The non-response rate and the floor and ceiling numbers of the CHI-VFQ-25 were calculated. The internal consistency was high in most subscales (except the general health and driving subscales), with Cronbach α ranging from 0.72-0.90. The test-retest reliability was excellent (intraclass correlation coefficient >0.90). Patients with worse visual acuity had significantly lower scores on the CHI-VFQ-25 supporting construct validity. Conclusion: The CHI-VFQ-25 is a reliable and valid tool for assessing the visual functions of Chinese patients with eye diseases in Hong Kong. Some questions had high non-response rates and should be substituted by the available alternatives.published_or_final_versio

Simultaneous spectral domain OCT and fundus autofluorescence imaging of the macula and microperimetric correspondence after successful repair of rhegmatogenous retinal detachment

Background/aims: To evaluate the ultrastructural changes in the macula after successful repair of rhegmatogenous retinal detachment (RRD) using simultaneous spectral domain optical coherence tomography (sdOCT) and fundus autofluorescence (FAF) imaging and to perform functional correlations with microperimetry. Methods: Simultaneous sdOCT and FAF imaging were performed using a combined sdOCT-confocal scanning laser ophthalmoscope (cSLO) system. Microperimetry was performed in a subgroup of these patients. Results: 17 patients with macular-on RRD and 20 with macular-off RRD were recruited. sdOCT images revealed disruption of the external limiting membrane, inner segment/outer segment junction or the Verhoeff membrane in 16 eyes (43.2%). The presence of any or more of these disruptions was significantly associated with a poor postoperative best-corrected visual acuity (BCVA) (p<0.001). Patients with abnormal FAF were also associated with poor postoperative BCVA (p<0.001). However, there was a generally poor correspondence between the localisation of ultrastructural abnormalities as detected by sdOCT and FAF changes. Areas of decreased microperimetric sensitivity corresponded well with the ultrastructural changes and abnormal FAF. Conclusions: FAF changes may lag behind ultrastructural changes in the OCT, some of which may reverse with the passage of time. The present study demonstrates the ultrastructural changes assessed with simultaneous FAF and sdOCT and their relation with visual outcome.published_or_final_versio

Risk factors for infection or colonization by levofloxacin-resistant Streptococcus pneumoniae in Hong Kong

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Integrating design and construction through virtual prototyping

Author name used in this publication: H. L. Guo2007-2008 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

Effect of clinical and virological parameters on the level of neutralizing antibody against pandemic influenza A virus H1N1 2009

Background. Little is known about the antibody response in natural infection by the novel 2009 influenza A (H1N1) virus and its relationship with clinical and virological parameters. The relative lack of background neutralizing antibody against this novel virus provides a unique opportunity for understanding this issue. Methods. Case patients presenting with influenza-like illness who were positive for the pandemic H1 gene by reverse transcription polymerase chain reaction were identified. The serum antibody response was assayed by neutralizing antibody titer (NAT) against the virus in 881 convalescent donors. We retrospectively analyzed clinical parameters and viral load. Results. Ninety percent of the 881 convalescent donors had seroprotective titer of 1:40 or greater. The geometric mean titer of donors with convalescent NAT measured between day 21 and 42 was 1:101.1. Multivariate analysis by ordinal regression showed that pneumonia (odds ratio, 3.39; 95% confidence interval, 1.49-9-7.61; P=.004) and sputum production (odds ratio, 1.75; 95% CI, 1.01-3.01; P=.046) were the 2 independent factors associated with a higher level of convalescent NAT. Being afebrile on influenza presentation was associated with subsequent poor NAT (<1:40) response (P = .04). A positive correlation between the nasopharyngeal viral load on presentation and the convalescent NAT was demonstrated (Spearman correlation r, 0.238; P = .026). Conclusions. About 10% of these convalescent patients do not have a seroprotective NAT and may benefit from vaccination to prevent reinfection. The convalescent NAT correlated well with the initial viral load and was independently associated with severity of the viral illness, including pneumonia. The findings provide both the clinical and virological markers for identifying potential convalescent plasma donors with high serum NAT, which can be used to produce hyperimmune intravenous immunoglobulin in a randomized treatment trial for patients with severe pandemic H1N1 infection. © 2010 by the Infectious Diseases Society of America. All rights reserved.published_or_final_versio

ASCI 2010 standardized practice protocol for cardiac magnetic resonance imaging: a report of the Asian society of cardiovascular imaging cardiac computed tomography and cardiac magnetic resonance imaging guideline working group

These practice guidelines are recommended by the Asian Society of Cardiovascular Imaging (ASCI), the sole society in Asia designated for cardiovascular imaging, to provide a framework to healthcare providers for suggested essential elements in cardiac magnetic resonance (CMR) examinations of different disease spectra. The guideline is composed of recommendations on the general technique, acquisition of some basic modules, and protocols on stress tests. The protocols for specific diseases are provided in a table format for quick reference to be easily utilized for everyday clinical CMR. © 2010 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201

Survival from cardiovascular events as predicated by carotid (common carotid artery) intima-media thickness and Doppler values in ischaemic Chinese patients requiring coronary angiogrm

INTRODUCTION: Carotid intima-media thickness (cIMT) of the common carotid artery may be correlated to the presence of coronary artery disease. However, the role of the cIMT and Doppler findings in predicting subsequent cardiovascular events has not been established. The aim of this study was to investigate the predictive value. METHODS: A total of 212 consecutive Chinese patients undergoing clinically driven coronary angiogram were evaluated. Carotid parameters (cIMT, peak systolic velocity [PSV] and end diastolic velocity, at the bulb, internal and common carotid artery, on both sides) were analysed using the IE33 auto-detection program. Patients were followed up and monitored for the occurrence of the primary composite end-point (PCEP), defined as all cardiovascular deaths, non-fatal MI, stroke, CHF, ACS or arrhythmias requiring hospitalisation or intervention. RESULTS: To date, the mean follow-up time was 534±234 days. The PCEP was reached in 25 subjects (11.8%). The right common cIMT was shown to be a predictor for critical coronary stenosis requiring PCI (area under ROC curve=0.626, P=0.001). cIMT <0.8 mm was associated with a better survival (log rank test, P=0.029). Univariate analysis, a right common cIMT of ≥0.8mm, the right common carotid PSV, and the waist circumference were independent predictors for the PCEP. Cox proportional hazards model adjusted for age showed the right common carotid PSV was the only independent predictor for the PCEP (HR=0.963; 95% CI, 0.939-0.987, P=0.002). Similar correlations were not observed with the overall (left and right) cIMT or the left cIMT in this study. CONCLUSION: The right common carotid PSV and the right common cIMT ≥0.8 mm are shown to predict the cardiovascular survival in this study. The latter also strongly correlates with the presence of critical coronary stenosis requiring intervention.published_or_final_versionThe 14th Medical Research Conference, Department of Medicine, The University of Hong Kong, Hong Kong, 10 January 2009. In Hong Kong Medical Journal, 2009, v. 15 suppl. 1, p. 23, abstract no. 3

Identification of novel porcine and bovine parvoviruses closely related to human parvovirus 4

Human parvovirus 4 (PARV4), a recently discovered parvovirus found exclusively in human plasma and liver tissue, was considered phylogenetically distinct from other parvoviruses. Here, we report the discovery of two novel parvoviruses closely related to PARV4, porcine hokovirus (PHoV) and bovine hokovirus (BHoV), from porcine and bovine samples in Hong Kong. Their nearly full-length sequences were also analysed. PARV4-like viruses were detected by PCR among 44.4% (148/333) of porcine samples (including lymph nodes, liver, serum, nasopharyngeal and faecal samples), 13% (4/32) of bovine spleen samples and 2% (7/362) of human serum samples that were sent for human immunodeficiency virus and hepatitis C virus antibody tests. Three distinct parvoviruses were identified, including two novel parvoviruses, PHoV and BHoV, from porcine and bovine samples and PARV4 from humans, respectively. Analysis of genome pequences from seven PHoV strains, from three BHoV strains and from one PARV4 strain showed that the two animal parvoviruses were most similar to PARV4 with 61.5-63% nt identities and, together with PARV4 (HHoV), formed a distinct cluster within the family Parvoviridae. The three parvoviruses also differed from other parvoviruses by their relatively large predicted VP1 protein and the presence of a small unique conserved putative protein. Based on these results, we propose a separate genus, Hokovirus, to describe these three parvoviruses. The co-detection of porcine reproductive and respiratory syndrome virus, the agent associated with the recent 'high fever' disease outbreaks in pigs in China, from our porcine samples warrants further investigation. © 2008 SGM.published_or_final_versio

Self-exciting threshold binomial autoregressive processes

We introduce a new class of integer-valued self-exciting threshold models, which is based on the binomial autoregressive model of order one as introduced by McKenzie (Water Resour Bull 21:645–650, 1985. doi:10.1111/j.1752-1688.1985. tb05379.x). Basic probabilistic and statistical properties of this class of models are discussed. Moreover, parameter estimation and forecasting are addressed. Finally, the performance of these models is illustrated through a simulation study and an empirical application to a set of measle cases in Germany