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Dive into the research topics where Lewis Chan is active.

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Featured researches published by Lewis Chan.


The Journal of Urology | 2008

Ultrasound Measurement of Bladder Wall Thickness in the Assessment of Voiding Dysfunction

Alison H. Blatt; Jehan Titus; Lewis Chan

PURPOSE Ultrasound measurement of bladder wall thickness has been proposed as a useful diagnostic parameter in patients with bladder outlet obstruction and other voiding dysfunctions. We assessed bladder wall thickness measurement as a noninvasive test in patients with suspected bladder outlet obstruction or overactive bladder syndrome. MATERIALS AND METHODS Transabdominal ultrasound measurement of bladder wall thickness was performed during urodynamic study in 180 patients with nonneurogenic voiding dysfunction. Two measurements of anterior bladder wall thickness, 1 cm apart in the midline and averaged, were obtained at 200 ml filling. Bladder wall thickness findings were correlated with urodynamic diagnoses. RESULTS A total of 180 patients with an average age of 62 years (range 20 to 94) were recruited, comprising 73 males and 107 females. Of the patients 69 had normal urodynamics, 39 had bladder outlet obstruction, 38 had increased bladder sensation on cystometry and 34 had detrusor overactivity. Bladder wall thickness was 1.1 to 4.5 mm in all groups. Males had a slightly thicker bladder wall than females (mean 2.1 vs 1.9 mm, p = 0.064). Mean bladder wall thickness in patients with normal urodynamics, bladder outlet obstruction, detrusor overactivity and increased bladder sensation was 2.0, 2.1, 1.9 and 1.8 mm, respectively. No significant difference was found between the groups (ANOVA p = 0.064, not significant). In particular there was no difference in bladder wall thickness between patients with normal urodynamics, and those with bladder outlet obstruction (p = 0.31) or detrusor overactivity (p = 0.309). CONCLUSIONS Bladder wall thickness is remarkably uniform in patients with nonneurogenic voiding dysfunction. Therefore, it cannot reliably predict bladder outlet obstruction or detrusor overactivity. Bladder wall thickness measurement does not provide an alternative to urodynamic studies for diagnosing voiding dysfunction.


Age and Ageing | 2010

Urinary incontinence and quality of life among older community-dwelling Australian men: the CHAMP study

P. W. Kwong; Robert G. Cumming; Lewis Chan; Markus J. Seibel; Vasi Naganathan; Helen Creasey; D. G. Le Couteur; Louise M. Waite; Philip N. Sambrook; David J. Handelsman

OBJECTIVE to describe the prevalence and impact on quality of life of urinary incontinence in a population-based cohort of older community-dwelling Australian men. SUBJECTS the population comprised 1,705 men aged >or=70 years participating in the Concord Health and Ageing in Men Project, a population-based study of urban older Australian men. METHODS data were collected between January 2005 and June 2007, and the participation rate was 47%. Data on demographics, medical history and from the 12-item Short Form Health Survey (SF-12) and International Consultation on Incontinence Questionnaire were collected. Urinary incontinence was defined as urinary leakage at least two times a week over the past 4 weeks. RESULTS the prevalence of urinary incontinence was 14.8%, increasing from 12.0% for men aged 70-74 years old to 16.3% for those aged >or=90 years, with urgency incontinence being the most frequent type of urinary incontinence. Daily urine leakage was reported by 3% of men. Men with incontinence had lower overall SF-12 scores with greater impact on the physical (PCS) than the mental (MCS) components of that scale. After adjusting for age, number of co-morbidities, enlarged prostate and prostate cancer, men with incontinence had worse PCS (43.6 vs 45.9) and MCS scores (52.2 vs 54.6) compared with continent men. CONCLUSION urinary incontinence is common among older community-dwelling men and is associated with worse quality of life with greater impact on physical than mental factors. As the population ages, urinary incontinence prevalence will increase and increased resources will be needed to address this growing problem.


BJUI | 2012

Diagnosing detrusor sphincter dyssynergia in the neurological patient.

Chasta-Dawne L. Bacsu; Lewis Chan; Vincent Tse

•  Detrusor sphincter dyssynergia (DSD) is variant of neurogenic bladder dysfunction caused by suprasacral neurological abnormalities and may be associated with serious complications if unrecognised. •  This paper focuses on the clinical features as well as challenges and limitations in the diagnosis of DSD.


The Journal of Urology | 2012

Transurethral Prostate Resection in Patients with Hypocontractile Detrusor—What is the Predictive Value of Ultrastructural Detrusor Changes?

Alison H. Blatt; Susan Brammah; Vincent Tse; Lewis Chan

PURPOSE Men with detrusor failure and chronic urinary retention have a lower voiding success rate and higher postoperative morbidity following transurethral prostatectomy than those with bladder outlet obstruction. Current investigations, including urodynamics, may be unable to predict the response to surgical treatment. We identified ultrastructural features on detrusor biopsy that correlated with the postoperative voiding outcome in patients with a hypocontractile detrusor undergoing transurethral prostatectomy. MATERIALS AND METHODS Detrusor biopsies were obtained from 17 patients with urodynamic evidence of bladder outlet obstruction or a hypocontractile detrusor undergoing transurethral prostatectomy and from 5 controls. Specimens were examined by transmission electron microscopy. Ten individual detrusor ultrastructural features were analyzed. Findings were compared with preoperative and postoperative clinical parameters. RESULTS Failure to void after transurethral prostatectomy was significantly associated with the ultrastructural features of variation in muscle cell size, muscle cell shape, collagenosis and abnormal fascicles. These 4 features were significantly associated with each other, defining a distinctive pattern of detrusor failure. For transurethral prostatectomy failure the sensitivity, specificity, and positive and negative predictive values of all 4 features together were 60%, 91%, 75% and 84%, respectively. Three or 4 features on detrusor biopsy predicted voiding failure. CONCLUSIONS Detrusor ultrastructural analysis is highly predictive of voiding outcome following transurethral prostatectomy in patients with detrusor failure. Patients with ultrastructural features previously described as part of the myohypertrophy pattern do not have a primary diagnosis of bladder outlet obstruction but rather detrusor failure secondary to bladder outlet obstruction.


British Journal of Clinical Pharmacology | 2015

Measuring anticholinergic drug exposure in older community-dwelling Australian men: a comparison of four different measures

Lisa Pont; Johannes T. H. Nielen; Andrew J. McLachlan; Danijela Gnjidic; Lewis Chan; Robert G. Cumming; Katja Taxis

AIMS Anticholinergic drug exposure is associated with adverse outcomes in older people. While a number of tools have been developed to measure anticholinergic drug exposure, there is limited information about the agreement and overlap between the various scales. The aim of this study was to investigate the agreement and overlap between different measures of anticholinergic drug exposure in a cohort of community-dwelling older men. METHODS A cross-sectional study was used to compare anticholinergic drug exposure calculated using the Anticholinergic Risk Scale (ARS), the Anticholinergic Drug Scale (ADS), the Anticholinergic Cognitive Burden (ACB) and the Drug Burden Index anticholinergic subscale (DBI-ACH) in a cohort of community-dwelling men aged 70 years and older (n = 1696). Statistical agreement, expressed as Cohens kappa (κ), between these measurements was calculated. RESULTS Differences were found between the tools regarding the classification of anticholinergic drug exposure for individual participants. Thirteen percent of the population used a drug listed as anticholinergic on the ARS, 39% used a drug listed on the ADS and the ACB, and 18% of the population used one or more anticholinergic drugs listed on the DBI-ACH. While agreement was good between the ACB and ADS (κ = 0.628, 95% CI 0.593, 0.664), little agreement was found between remaining tools (κ = 0.091-0.264). CONCLUSIONS With the exception of the ACB and ADS, there was poor agreement regarding anticholinergic drug exposure among the four tools compared in this study. Great care should be taken when interpreting anticholinergic drug exposure using existing scales due to the wide variability between the different scales.


BJUI | 2011

Outlet obstruction after sling surgery

Vincent Tse; Lewis Chan

Whats known on the subject? and What does the study add?


International Neurourology Journal | 2014

Clinical Outcome in Male Patients With Detrusor Overactivity With Impaired Contractility

Shuo Liu; Lewis Chan; Vincent Tse

Purpose To review the clinical outcomes of patients with voiding dysfunction who have detrusor overactivity with impaired contractility (DOIC) diagnosed with urodynamic studies. Methods Urodynamic reports from 2005 to 2009 were reviewed, and 54 male patients had findings consistent with DOIC. Patients with acontractile or neuropathic bladders were excluded. Clinical outcomes were obtained from patient records. Results Of 54 men, 8 presented with voiding symptoms, 17 had storage symptoms, and 29 had mixed symptoms. Twenty-two had a previous transurethral resection of the prostate. The median follow-up was 12 months. Four patients received no intervention. Two patients were taught intermittent self-catheterization. Five patients underwent surgery to reduce outlet resistance and all reported improvement. Forty-three patients were started on pharmacotherapy; symptomatic improvement was reported by 9 of 16 patients commenced on anticholinergics alone, 6 of 16 on alpha-blockers alone, and 4 of 5 treated with a combination of alpha-blockers and anticholinergics. Eleven patients experienced no difference on pharmacotherapy and 2 reported deterioration. One patient developed acute urinary retention (18 months after commencing treatment with alpha-blockers). No patient had urosepsis. Conclusions Anticholinergics and alpha-blockers appear to be safe in patients with DOIC. The risk of urinary retention and sepsis is low. The majority of patients report symptomatic benefit from either drugs or surgical treatment.


BJUI | 2012

Practical uroflowmetry: PRACTICAL UROFLOWMETRY

Thomas R. Jarvis; Lewis Chan; Vincent Tse

Uroflowmetry is an essential investigation that can assist in the diagnosis of common lower urinary tract dysfunctions. This article describes key aspects on performing and interpreting the test.


The Aging Male | 2016

A systematic review of the association between lower urinary tract symptoms and falls, injuries, and fractures in community-dwelling older men

Naomi Noguchi; Lewis Chan; Robert G. Cumming; Fiona M. Blyth; Vasi Naganathan

Abstract Background: Lower urinary tract symptoms (LUTS) have been associated with falls in studies either exclusively or predominantly of women. It is, therefore, less clear if LUTS are risk factors for falls in men. Methods: We conducted a systematic review of the literature on the association between LUTS and falls, injuries, and fractures in community-dwelling older men. Medline, Embase, and Cinahl were searched for any type of observational study that has been published in a peer-reviewed journal in English language. Studies were excluded if they did not report male-specific data or targeted specific patient populations. Results were summarized qualitatively. Results: Three prospective cohort studies and six cross-sectional studies were identified. Incontinence, urgency, nocturia, and frequency were consistently shown to have weak to moderate association with falls (the point estimates of odds ratio and relative risk ranged from 1.31 to 1.67) in studies with low risk of bias for confounding. Only frequency was shown to be associated with fractures. Conclusions: Urinary incontinence and lower urinary tract storage symptoms are associated with falls in community-dwelling older men. The circumstances of falls in men with LUTS need to be investigated to generate hypotheses about what types of interventions may be effective in reducing falls.


The Journal of Urology | 2016

Lower Urinary Tract Symptoms and Incident Falls in Community Dwelling Older Men: The Concord Health and Ageing in Men Project

Naomi Noguchi; Lewis Chan; Robert G. Cumming; Fiona M. Blyth; David J. Handelsman; Markus J. Seibel; Louise M. Waite; David G. Le Couteur; Vasi Naganathan

PURPOSE We sought to determine which lower urinary tract symptoms are associated with incident falls in community dwelling older men. MATERIALS AND METHODS The Concord Health and Ageing in Men Project involves a representative sample of community dwelling men 70 years old or older in a defined geographic region in Sydney, New South Wales, Australia. Included in analysis were 1,090 men without neurological diseases, poor mobility or dementia at baseline. Lower urinary tract symptoms were assessed using I-PSS (International Prostate Symptom Score) and incontinence was assessed using ICIQ (International Consultation on Incontinence Questionnaire) at baseline. I-PSS subscores were calculated for storage and voiding symptoms. Incident falls in 1 year were determined by telephone followup every 4 months. RESULTS I-PSS storage and voiding subscores were associated with falls. Urgency incontinence was associated with falls (adjusted incidence rate ratio 2.57, 95% CI 1.54-4.30). In addition, intermediate to high I-PSS storage subscores without urgency incontinence were associated with falls (adjusted incidence rate ratio 1.72, 95% CI 1.24-2.38). Other types of incontinence and urgency alone without urgency incontinence were not associated with falls. CONCLUSIONS Lower urinary tract storage and voiding symptoms were associated with falls in community dwelling older men. Of the symptoms of overactive bladder urgency incontinence carried a high risk of falls. Storage symptoms also contributed to the fall risk independently of urgency incontinence. Circumstances of falls among men with lower urinary tract symptoms should be explored to understand how lower urinary tract symptoms increase the fall risk and generate hypotheses regarding potential interventions. Furthermore, trials to treat lower urinary tract symptoms in older men should include falls as an end point.

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Vincent Tse

Concord Repatriation General Hospital

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Ruth Collins

Concord Repatriation General Hospital

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David Habashy

Concord Repatriation General Hospital

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Susan Brammah

Concord Repatriation General Hospital

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Edward J. Wills

Concord Repatriation General Hospital

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