Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 85
Filter
1.
Rev Sci Instrum ; 94(5)2023 May 01.
Article in English | MEDLINE | ID: mdl-37227195

ABSTRACT

We present the detailed metrology of a superconducting Transition-Edge Sensor (TES) absorber-coupled bolometer array bonded to a variable-delay backshort to form an integral field unit. The backshort is shaped as a wedge to continuously vary the electrical phase delay of the bolometer absorber reflective termination across the array. This resonant absorber termination structure is used to define a spectral response over a 4:1 bandwidth in the far-infrared, from ∼30 to 120 µm. The metrology of the backshort-bolometer array hybrid was achieved with a laser confocal microscope and a compact cryogenic system that provides a well-defined thermal (radiative and conductive) environment for the hybrid when cooled to ∼10 K. The results show the backshort free-space delays do not change with cooling. The estimated backshort slope is 1.58 milli-radians and within 0.3% of the targeted value. The sources of error in the free-space delay of the hybrid and optical cryogenic metrology implementations are discussed in detail. We also present measurements of the bolometer's single-crystal silicon membrane topography. The membranes deform and deflect out-of-plane under both warm and cold conditions. Intriguingly, the optically active area of the membranes tends to flatten when cold and repeatably achieve the same mechanical state over many thermal cycles; hence, no evidence for thermally-induced mechanical instability is observed. Most of the cold deformation is sourced from thermally-induced stress in the metallic layers comprising the TES element of the bolometer pixels. These results provide important considerations for the design of ultra-low-noise TES bolometers.

2.
Article in English | MEDLINE | ID: mdl-33967568

ABSTRACT

Excess heat capacity in a bolometric detector has the consequence of increasing or leading to multiple device time constants. The Mo/Au bilayer transition edge sensor (TES) bolometric detectors initially fabricated for the high resolution mid-infrared spectrometer (HIRMES) exhibited two response thermalization scales, one of which is a few times longer than estimates based upon the properties of the bulk materials employed in the design. The relative contribution of this settling time to the overall time response of the detectors is roughly proportional to the pixel area, which ranges between ~0.3 and 2.6 mm2. Use of laser ablation to remove sections of the silicon membranes comprising the pixels results in a detector response with a smaller contribution from the secondary time constant. Additional information about the nature of this excess heat capacity is gleaned from glancing incidence x-ray diffraction, which reveals the presence of molybdenum silicides near the silicon surface which is a consequence of the bi-layer deposition. Quantitative analysis of the concentration of excess molybdenum, estimated with secondary ion mass spectroscopy, is commensurate to the additional heat capacity needed to explain the anomalous time response of the detectors.

3.
J Mech Behav Biomed Mater ; 116: 104343, 2021 04.
Article in English | MEDLINE | ID: mdl-33513459

ABSTRACT

A shear-punch test (SPT) experimental method was developed to address the lack of shear deformation and failure response data for the human skull as a function of local bone microarchitecture. Improved understanding of skull deformation and fracture under varying stress-states helps implement mechanism-based, multi-axial material models for finite element analysis for optimizing protection strategies. Shear-punch coupons (N = 47 specimens) were extracted from right-parietal and frontal bones of three fresh-frozen-thawed human skulls. The specimens were kept as full through-thickness or segmented into the three skull constituent layers: the inner and outer cortical tables and the middle porous diploë. Micro-computed x-ray tomography (µCT) before and after SPT provided the bone volume fraction (BVF) as a function of depth for correlation to shear mechanisms in the punched volumes. Digital image correlation was used to track displacement of the punch above the upper die to minimize compliance error. Five full-thickness specimens were subjected to partial indentation loading to investigate the process of damage development as a function of BVF and depth. It was determined that BVF dominates the shear yield and ultimate strength of human skull bone, but the imposed uniaxial loading rate (0.001 and 0.1 s-1) did not have as strong a contribution (p = 0.181-0.806 > 0.05) for the shear yield and ultimate strength of the skull bone layer specimens. Shear yield and ultimate strength data were highly correlated to power law relationships of BVF (R2 = 0.917-0.949). Full-thickness and partial loaded SPT experiments indicate the diploë primarily dictates the shear strength of the intact structure.


Subject(s)
Bone and Bones , Skull , Finite Element Analysis , Frontal Bone , Humans , Porosity , Shear Strength , Skull/diagnostic imaging , Stress, Mechanical
4.
Sci Rep ; 10(1): 15360, 2020 09 21.
Article in English | MEDLINE | ID: mdl-32958812

ABSTRACT

Skeletal muscle tissue demonstrates global hypermethylation with age. However, methylome changes across the time-course of differentiation in aged human muscle derived cells, and larger coverage arrays in aged muscle tissue have not been undertaken. Using 850K DNA methylation arrays we compared the methylomes of young (27 ± 4.4 years) and aged (83 ± 4 years) human skeletal muscle and that of young/aged heterogenous muscle-derived human primary cells (HDMCs) over several time points of differentiation (0, 72 h, 7, 10 days). Aged muscle tissue was hypermethylated compared with young tissue, enriched for; pathways-in-cancer (including; focal adhesion, MAPK signaling, PI3K-Akt-mTOR signaling, p53 signaling, Jak-STAT signaling, TGF-beta and notch signaling), rap1-signaling, axon-guidance and hippo-signalling. Aged cells also demonstrated a hypermethylated profile in pathways; axon-guidance, adherens-junction and calcium-signaling, particularly at later timepoints of myotube formation, corresponding with reduced morphological differentiation and reductions in MyoD/Myogenin gene expression compared with young cells. While young cells showed little alterations in DNA methylation during differentiation, aged cells demonstrated extensive and significantly altered DNA methylation, particularly at 7 days of differentiation and most notably in focal adhesion and PI3K-AKT signalling pathways. While the methylomes were vastly different between muscle tissue and HDMCs, we identified a small number of CpG sites showing a hypermethylated state with age, in both muscle tissue and cells on genes KIF15, DYRK2, FHL2, MRPS33, ABCA17P. Most notably, differential methylation analysis of chromosomal regions identified three locations containing enrichment of 6-8 CpGs in the HOX family of genes altered with age. With HOXD10, HOXD9, HOXD8, HOXA3, HOXC9, HOXB1, HOXB3, HOXC-AS2 and HOXC10 all hypermethylated in aged tissue. In aged cells the same HOX genes (and additionally HOXC-AS3) displayed the most variable methylation at 7 days of differentiation versus young cells, with HOXD8, HOXC9, HOXB1 and HOXC-AS3 hypermethylated and HOXC10 and HOXC-AS2 hypomethylated. We also determined that there was an inverse relationship between DNA methylation and gene expression for HOXB1, HOXA3 and HOXC-AS3. Finally, increased physical activity in young adults was associated with oppositely regulating HOXB1 and HOXA3 methylation compared with age. Overall, we demonstrate that a considerable number of HOX genes are differentially epigenetically regulated in aged human skeletal muscle and HDMCs and increased physical activity may help prevent age-related epigenetic changes in these HOX genes.


Subject(s)
DNA Methylation/genetics , Exercise/physiology , Genes, Homeobox/genetics , Genome, Human/genetics , Muscle Cells/physiology , Muscle, Skeletal/physiology , Adult , Aged, 80 and over , CpG Islands/genetics , Epigenesis, Genetic/genetics , Epigenomics/methods , Female , Gene Expression/genetics , Humans , Male , Signal Transduction/genetics
5.
Diabetes Res Clin Pract ; 157: 107876, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31586661

ABSTRACT

AIMS: To assess outcomes of women in the Pregnancy and Neonatal Diabetes Outcomes in Remote Australia (PANDORA) cohort with gestational diabetes mellitus (GDM) managed by lifestyle modification compared with women without hyperglycaemia in pregnancy. METHODS: Indigenous (n = 97) and Europid (n = 113) women managed by lifestyle modification were compared to women without hyperglycaemia (n = 235). Multivariate linear and logistic regressions assessed whether GDM-lifestyle women had poorer outcomes compared to women without hyperglycaemia. RESULTS: Women with GDM-lifestyle had higher body mass index and lower gestational weight gain than women without hyperglycaemia. On univariate analysis, gestational age at delivery was lower and induction rates were higher in women with GDM-lifestyle than without hyperglycaemia. On multivariable regression, GDM-lifestyle was associated with lower gestational age at delivery (by 0.73 weeks), lower birthweight z-score (by 0.26, p = 0.007), lower likelihood of large for gestational age (LGA) [OR (95% CI): 0.55 (0.28, 1.02), p = 0.059], and greater likelihood of labour induction [2.34 (1.49, 3.66), p < 0.001] than women without hyperglycaemia. CONCLUSION: Women with GDM managed by lifestyle modification had higher induction rates and their offspring had lower birthweight z-scores, with a trend to lower LGA than those without hyperglycaemia in pregnancy. Further studies are indicated to explore reasons for higher induction rates.


Subject(s)
Birth Weight/genetics , Diabetes, Gestational/therapy , Life Style , Pregnancy Complications/therapy , Adolescent , Adult , Female , Humans , Pregnancy , Young Adult
6.
J Am Coll Radiol ; 16(6): 840-844, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30833164

ABSTRACT

OBJECTIVE: Radiology is a finite health care resource in high demand at most health centers. However, anticipating fluctuations in demand is a challenge because of the inherent uncertainty in disease prognosis. The aim of this study was to explore the potential of natural language processing (NLP) to predict downstream radiology resource utilization in patients undergoing surveillance for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: All HCC surveillance CT examinations performed at our institution from January 1, 2010, to October 31, 2017 were selected from our departmental radiology information system. We used open source NLP and machine learning software to parse radiology report text into bag-of-words and term frequency-inverse document frequency (TF-IDF) representations. Three machine learning models-logistic regression, support vector machine (SVM), and random forest-were used to predict future utilization of radiology department resources. A test data set was used to calculate accuracy, sensitivity, and specificity in addition to the area under the curve (AUC). RESULTS: As a group, the bag-of-word models were slightly inferior to the TF-IDF feature extraction approach. The TF-IDF + SVM model outperformed all other models with an accuracy of 92%, a sensitivity of 83%, and a specificity of 96%, with an AUC of 0.971. CONCLUSIONS: NLP-based models can accurately predict downstream radiology resource utilization from narrative HCC surveillance reports and has potential for translation to health care management where it may improve decision making, reduce costs, and broaden access to care.


Subject(s)
Carcinoma, Hepatocellular/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Machine Learning/economics , Natural Language Processing , Tomography, X-Ray Computed/economics , Aged , Area Under Curve , Databases, Factual , Female , Health Resources/statistics & numerical data , Humans , Machine Learning/statistics & numerical data , Male , Middle Aged , Ontario , Predictive Value of Tests , ROC Curve , Radiology Department, Hospital , Radiology Information Systems , Research Report , Retrospective Studies , Sensitivity and Specificity , Tomography, X-Ray Computed/methods
7.
J Mech Behav Biomed Mater ; 90: 404-416, 2019 02.
Article in English | MEDLINE | ID: mdl-30445367

ABSTRACT

Bone is a complex hierarchal structured material with varying porosity and mechanical properties. In particular, human cranial bone is essentially a natural composite consisting of low porosity outer and inner tables and a cancellous interior, or diploë. Experimental studies of biomechanically accurate cranial bone analogues are of high importance for biomechanical, forensics, and clinical researchers, which could improve the understanding and prevention of traumatic injury. Many reported studies use commercially available bone surrogates to draw biomechanical and forensics conclusions; however, their mechanical properties are not tabulated over a range of strain rates. This study elucidates the mechanical viability of three leading commercially available bone surrogates, i.e. Synbone, Sawbone, and Bonesim, over a large range of strain rates (10-3 to 103 s-1). Quasi-static compression testing was conducted using a universal testing machine and a Split-Hopkinson Pressure bar system equipped with high-speed video was used to determine the dynamic mechanical behavior of these materials. Micro-computed X-ray tomography (XRT) were performed on each material to investigate their pore structures and distributions. All materials exhibited strain rate dependent strength behavior, particularly at high loading rates (≥103 s-1). The Young's modulus was found to increase with strain rate from 10-3 to 10-1 s-1 for transversely and longitudinally loaded surrogate materials except for Synbone and the higher density Bonesim. The higher density Bonesim was determined to be the most suitable cranial bone simulant tested based on a combination of transverse Young's Modulus (1500 MPa), yield strength (19 MPa), ultimate strength (49 MPa), and ultimate strain (17%). These materials show limited promise for applications where the measured elastic properties and strengths are of interest.


Subject(s)
Biomimetic Materials , Bone and Bones , Materials Testing , Mechanical Phenomena , Stress, Mechanical , Weight-Bearing
8.
Diabetes Res Clin Pract ; 129: 105-115, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28521194

ABSTRACT

AIMS: Preconception care may decrease adverse pregnancy outcomes associated with pre-existing diabetes mellitus. Aboriginal Australians are at high risk of type 2 diabetes mellitus (T2DM), with earlier onset. We explored practitioner views on preconception care delivery for women with T2DM in the Northern Territory, where 31% of births are to Aboriginal women. METHODS: Mixed-methods study including cross-sectional survey of 156 health practitioners and 11 semi-structured interviews. RESULTS: Practitioners reported low attendance for preconception care however, 51% provided counselling on an opportunistic basis. Rural/remote practitioners were most likely to find counselling feasible. The majority (69%) utilised appropriate guidelines and addressed lifestyle modifications including smoking (81%), weight management (79%), and change medications appropriately such as ceasing ACE inhibitors (69%). Fewer (40%) prescribed the recommended dose of folate (5mg) or felt comfortable recommending delaying pregnancy to achieve optimal preconception glucose control (42%). Themes identified as barriers to care included the complexity of care setting and infrequent preconception consultations. There was a focus on motivation of women to make informed choices about conception, including birth spacing, timing and contraception. Preconception care enablers included cross-cultural communication, a multi-disciplinary care team and strong client-based relationships. CONCLUSIONS: Health practitioners are keen to provide preconception counselling and reported knowledge of evidence-based guidelines. Improvements are needed in recommending high dose folate and optimising glucose control. Cross-cultural communication and team-based care were reported as fundamental to successful preconception care in women with T2DM. Continued education and policy changes are required to support practitioners in opportunities to enhance pregnancy planning.


Subject(s)
Diabetes Mellitus, Type 2/complications , Preconception Care/methods , Adult , Cross-Sectional Studies , Female , Humans , Pregnancy , Pregnancy Complications
9.
J Lesbian Stud ; 20(2): 251-65, 2016.
Article in English | MEDLINE | ID: mdl-26914825

ABSTRACT

Discussions of public sexual spaces in the social science literature have, until recently, been dominated by analyses of men's use of these spaces for erotic expression. In the late 1990s, feminist collectives began to explore the emancipatory potentials these spaces can have for lesbian sexualities. After a police raid on one such event called the "Pussy Palace," scholars in diverse disciplines began to explore how these events have both opened up and restricted erotic possibilities for lesbians, queer women, and trans* attendees. This article reviews the existing social science literature on lesbian and queer bathhouse events and highlights several key themes and subthemes that have dominated the discourse, including the importance that these spaces be recognized for their ability to both shape and be shaped by principles of community, safety, and sexual health/wellness.


Subject(s)
Homosexuality, Female , Homosexuality, Male , Public Facilities , Sexual Behavior , Baths , Female , Humans , Male , Social Behavior
10.
J Lesbian Stud ; 20(1): 65-86, 2016.
Article in English | MEDLINE | ID: mdl-26701770

ABSTRACT

Previous research has explored the affiliation and distancing strategies employed in published memoirs of gender transition. In this article, we are particularly interested in elucidating the ways in which individuals construct identities and characterize their sexualities, and how sociohistorical constraints might influence what is expressed with respect to this in personal narratives of transition. Using the memoirs of Lili Elbe (Hoyer, 1933) and Joy Ladin (2013) as conceptual brackets, this article investigates the complex relationship between the development and articulation of trans* identities and lesbian sexualities within the context of published memoirs of gender transition.


Subject(s)
Homosexuality, Female/psychology , Transgender Persons/psychology , Female , Gender Identity , Humans , Male , Personal Narratives as Topic , Sex Reassignment Surgery/psychology , Women's Rights
11.
Cochrane Database Syst Rev ; (4): CD006344, 2007 Oct 17.
Article in English | MEDLINE | ID: mdl-17943904

ABSTRACT

BACKGROUND: Asthma education is regarded as an important step in the management of asthma in national guidelines. Racial and socio-economic factors are associated with markers of asthma severity, including recurrent acute presentations to emergency health facilities. Worldwide, indigenous groups are disproportionately represented in the severe end of the asthma spectrum. Appropriate models of care are important in the successful delivery of services, and are likely contributors to improved outcomes for people with asthma. OBJECTIVES: To determine whether involvement of an indigenous healthcare worker (IHW) in comparison to absence of an IHW in asthma education programmes, improves asthma related outcomes in indigenous children and adults with asthma. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Airways Group Specialised Register, MEDLINE and EMBASE databases, review articles and reference lists of relevant articles. The latest search was in December 2006. SELECTION CRITERIA: All randomised controlled trials comparing involvement of an indigenous healthcare worker (IHW) in comparison to absence of an IHW in asthma education programmes for indigenous people with asthma. DATA COLLECTION AND ANALYSIS: Two independent review authors selected data for inclusion, a single author extracted the data. Both review authors independently assessed study quality. We contacted authors for further information. As it was not possible to analyse data as "intention-to-treat", we analysed data as "treatment received". MAIN RESULTS: Only a single study was applicable for this review, and included 24 children randomised to an asthma education programme involving an IHW, compared to a similar intervention without an IHW. Twenty two of these children completed the trial. Only one outcome (asthma knowledge in children, mean difference of 3.30 units, 95% CI 1.07 to 5.53) significantly favoured the IHW involvement group. However, although not statistically significant, all the outcomes favoured the group that had IHW involvement in the asthma education program. There were no studies in adults. AUTHORS' CONCLUSIONS: The involvement of IHW in asthma programs targeted for their own ethnic group in one small trial was beneficial for some but not all asthma outcomes. Thus there is insufficient data to be confident that the involvement of IHW is beneficial in all settings. Nevertheless, given the complexity of health outcomes and culture as well as the importance of self-determination for indigenous peoples, the practice of including IHW in asthma education programs for indigenous children and adults with asthma is justified, but should be subject to further randomised controlled trials.


Subject(s)
Asthma/therapy , Community Health Workers , Health Services, Indigenous , Minority Groups , Adult , Asthma/ethnology , Black People , Child , Hispanic or Latino , Humans , Native Hawaiian or Other Pacific Islander
12.
Ann Oncol ; 17(1): 151-6, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16236755

ABSTRACT

BACKGROUND: The goal of this study was to identify aspects of care (predictors) that can most easily be modified to produce an improvement in the score of patients' overall evaluations of the quality of care received. PATIENTS AND METHODS: Our sample consisted of 2247 cancer patients hospitalized in Ontario acute care hospitals in 1999/2000. We sought predictors of patients' overall perceptions of the quality of care by applying a methodology that minimizes the improvement of the predictors while gaining a desired increase in the score of the dependent variable. This approach tends to ignore items that rate relatively high and focuses on those for which hospitals can more easily modify the score. Two main subgroups were analyzed in this study: patients with malignant and benign neoplasms. RESULTS: 'Skills of nursing staff', 'courtesy of nursing staff', 'courtesy of people who drew blood' and 'cleanliness of hospital in general' were consistently selected by our approach in both cancer groups. CONCLUSIONS: This study identifies an efficient approach to improving the score of patients' overall perceptions of the quality of care received. By focusing on these aspects of care, hospitals may be able to improve the allocation of scarce resources when planning patient satisfaction improvement initiatives.


Subject(s)
Neoplasms/nursing , Oncology Nursing/standards , Patient Satisfaction/statistics & numerical data , Quality Indicators, Health Care , Quality of Health Care/statistics & numerical data , Adolescent , Adult , Aged , Female , Health Care Surveys , Humans , Male , Middle Aged , Neoplasms/psychology , Oncology Nursing/statistics & numerical data , Ontario , Psychometrics , Surveys and Questionnaires/standards
15.
Acta Cytol ; 45(4): 509-14, 2001.
Article in English | MEDLINE | ID: mdl-11480710

ABSTRACT

Cost-effectiveness analyses are an important source of information for the design and evaluation of policies to reduce cervical cancer. This paper describes the recommendations of a panel on cost-effectiveness studies convened as part of the International Consensus Conference on the Fight Against Cervical Cancer. Recommendations for cost-effectiveness studies include: (1) the use of reference case methods to support comparisons across studies, (2) the use of a consistent standard of evidence on the clinical effectiveness of different screening strategies, (3)further research into the costs and effectiveness of different screening and treatment strategies for cervical cancer, (4) further research into screening and treatment strategies in a wide range of countries, (5) easily accessible and detailed descriptions of the methods and supplementary analyses underlying published studies, (6) greater use of newly developed models of cervical cancer, and (7) greater revelation of potential conflict of interest by researchers.


Subject(s)
Cost-Benefit Analysis/methods , Mass Screening/economics , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/economics , Vaginal Smears/economics , Conflict of Interest , Female , Health Care Costs , Health Services Research/methods , Humans , Research
16.
Can J Public Health ; 92(2): 155-9, 2001.
Article in English | MEDLINE | ID: mdl-11338156

ABSTRACT

BACKGROUND: Appropriate and timely provision of ambulatory care is an important factor in maintaining population health and in avoiding unneccessary hospital use. This article describes conditions for which hospitalization rates have a strong and inverse relationship to access to high-quality ambulatory care. METHODS: Three panels of Canadian physicians following different consensus techniques selected conditions for which the relative risk of hospitalization is inversely related to ambulatory care access. PRINCIPAL FINDINGS: All panels identified asthma, angina pectoris, congestive heart failure, otitis media, gastric ulcer, pelvic inflammatory disease, malignant hypertension, and immunization-preventable infections as ambulatory care-sensitive admissions. These conditions strongly overlap with lists developed for similar purposes in the U.S. and England. INTERPRETATION: Ambulatory care-sensitive conditions represent an intermediate health outcome. They are distinct from inappropriate hospitalizations. They may be useful for measuring the impact of health care policy, and for performance measurement or audit.


Subject(s)
Ambulatory Care/standards , Data Collection/methods , Health Services Accessibility/standards , Health Services Research/methods , Hospitalization/statistics & numerical data , Quality of Health Care , Angina Pectoris/therapy , Asthma/therapy , Canada , Delphi Technique , Female , Health Policy , Heart Failure/therapy , Humans , Hypertension, Malignant/therapy , Infections/therapy , Male , Medical Audit , Otitis Media/therapy , Outcome Assessment, Health Care , Pelvic Inflammatory Disease/therapy , Risk Factors , Stomach Ulcer/therapy , Vaccination/standards
18.
J Cataract Refract Surg ; 27(4): 593-603, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11311630

ABSTRACT

PURPOSE: To evaluate the safety and predictability of laser in situ keratomileusis (LASIK) retreatment following primary procedures for high myopia and astigmatism. SETTING: Corneal Diseases and Excimer Laser Research Unit, Department of Ophthalmology, University of Dundee, Dundee, United Kingdom. METHODS: This prospective observational study of retreatment comprised a cohort of 109 eyes having primary LASIK for high myopia and astigmatism with a spherical equivalent (SE) of -9.70 diopters (D) +/- 4.06 (SD). Twenty-four eyes (22%) with an initial myopic SE of -9.83 +/- 3.50 D, a comparable subset of the entire group (P < .05), had retreatment for residual myopia (-3.02 +/- 2.17 D) to improve uncorrected visual acuity (UCVA) by reelevating the corneal flap and ablating the stromal bed. RESULTS: The mean follow-up after retreatment was 12.8 +/- 5.1 months (range 1.5 to 24 months; 19 eyes >/=6 months, 13 eyes > or = 12 months). The mean myopic SE was reduced to +0.53 +/- 0.62 D at 1 week, +0.05 +/- 0.50 D at 1 month, +0.30 +/- 0.50 D at 6 months, and +0.18 +/- 0.42 D at the latest follow-up, 12.8 months. At the latest review, 62% of eyes were within +/-0.50 D of emmetropia and 100% were within +/-1.00 D. The mean refraction did not alter statistically between 1 week and subsequent times. The mean UCVA improved from 6/30 prior to retreatment to 6/9 at the latest follow-up. Uncorrected visual acuity of 6/6 or better, 6/9 or better, and 6/12 or better was achieved by 33.0%, 75.0%, and 95.8% of eyes, respectively. No significant complications that led to a loss of best corrected visual acuity were encountered, although retreatment procedures were more uncomfortable than primary procedures and self-limiting; epithelial ingrowth that did not threaten vision was common, and 2 patients complained of nighttime visual symptoms. CONCLUSIONS: Retreatment of residual myopia by reelevating the flap was relatively safe and predictable, with a low risk of sight-threatening complications. However, longer term studies may be required to detect late complications.


Subject(s)
Corneal Stroma/surgery , Keratomileusis, Laser In Situ , Myopia/surgery , Surgical Flaps , Adult , Astigmatism/surgery , Cohort Studies , Female , Humans , Male , Middle Aged , Postoperative Complications , Prospective Studies , Refraction, Ocular , Reoperation , Safety , Treatment Outcome , Visual Acuity
19.
J Obstet Gynaecol ; 21(2): 162-5, 2001 Mar.
Article in English | MEDLINE | ID: mdl-12521888

ABSTRACT

Abdominovaginal sling surgery is performed in women with genuine stress incontinence. It is not usually a primary operation because of the higher morbidity compared to the colposuspension. Slings are indicated in incontinent women with previous failed surgery, urethral hypermobility, intrinsic sphincter weakness, significant anterior vaginal wall prolapse or those with restricted vaginal mobility. This study was undertaken to assess long-term patient perceived success of abdominovaginal sling surgery in women with genuine stress incontinence (GSI) in the presence of a cystocoele. The case notes were reviewed of all 37 women undergoing sling surgery for GSI in the presence of a significant cystocoele between 1988 and 1999. Patients were sent a questionnaire at a minimum follow-up of 12 months enquiring about urinary symptoms. The mean duration of follow-up was 49 months. Six weeks following surgery 33/37 (89%) were completely dry. Thirty-three women (89%) responded to the questionnaire. Of these 14/33 (42%) were totally dry, 10/33 (30%) had insignificant leakage and 9/33 required regular protection. The mean visual analogue score of improvement in incontinence was 75.3 (+/-30.1). The operation was deemed successful in 24/33 (72%) women. Voiding difficulty was reported in 12% and recurrent prolapse occurred in 15%. Of the failures 8/9 reported urge incontinence and 4/9 stress incontinence. Frequency, urgency and urge incontinence were significantly more common in the women in whom the operation failed. This study demonstrates a 72% long-term success of abdominovaginal sling operations in women with GSI and a significant cystocoele. Development of DI accounted for most of the operative failures.

20.
J Natl Cancer Inst ; 92(21): 1731-9, 2000 Nov 01.
Article in English | MEDLINE | ID: mdl-11058616

ABSTRACT

BACKGROUND: The costs and side effects of several antiandrogen therapies for advanced prostate cancer differ substantially. We estimated the cost-effectiveness of antiandrogen therapies for advanced prostate cancer. METHODS: We performed a cost-effectiveness analysis using a Markov model based on a formal meta-analysis and literature review. The base case was assumed to be a 65-year-old man with a clinically evident, local recurrence of prostate cancer. The model used a societal perspective and a time horizon of 20 years. Six androgen suppression strategies were evaluated: diethylstilbestrol (DES), orchiectomy, a nonsteroidal antiandrogen (NSAA), a luteinizing hormone-releasing hormone (LHRH) agonist, and combinations of an NSAA with an LHRH agonist or orchiectomy. Outcome measures were survival, quality-adjusted life years (QALYs), lifetime costs, and incremental cost-effectiveness ratios. RESULTS: DES, the least expensive therapy, had a discounted lifetime cost of $3600 and the lowest quality-adjusted survival, 4.6 QALYs. At a cost of $7000, orchiectomy was associated with 5.1 QALYs, resulting in an incremental cost-effectiveness ratio of $7500/QALY relative to DES. All other strategies-LHRH agonists, NSAA, and both combined androgen blockade strategies-had higher costs and lower quality-adjusted survival than orchiectomy. These results were sensitive to the quality of life associated with orchiectomy and the efficacy of combined androgen blockade, and they changed little when prostate-specific antigen results were used to guide therapy. Under a wide range of other assumptions, the cost-effectiveness of orchiectomy relative to DES was consistently less than $20 000/QALY. Androgen suppression therapies were most cost-effective if initiated after patients became symptomatic from prostate metastases. CONCLUSIONS: For men who accept it, orchiectomy is likely to be the most cost-effective androgen suppression strategy. Combined androgen blockade is the least economically attractive option, yielding small health benefits at high relative costs.


Subject(s)
Androgen Antagonists/economics , Antineoplastic Agents, Hormonal/economics , Diethylstilbestrol/economics , Orchiectomy/economics , Prostatic Neoplasms/economics , Prostatic Neoplasms/therapy , Quality of Life , Aged , Androgen Antagonists/therapeutic use , Antineoplastic Agents, Hormonal/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/economics , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cost-Benefit Analysis , Diethylstilbestrol/therapeutic use , Disease Progression , Gonadotropin-Releasing Hormone/agonists , Humans , Male , Markov Chains , Neoplasm Recurrence, Local/therapy , Prostate-Specific Antigen/blood , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/immunology , Prostatic Neoplasms/surgery , Quality-Adjusted Life Years , Survival Analysis , Time Factors , Treatment Outcome , United States
SELECTION OF CITATIONS
SEARCH DETAIL