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1.
Opt Lett ; 47(6): 1383-1386, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35290319

RESUMEN

We present an open-source eigenmode expansion (EME) software package entirely implemented in the Python programming language. Eigenmode expansion Python (EMEPy) utilizes artificial neural networks to reproduce electromagnetic eigenmode field profiles to accelerate the EME process by a factor of 3. EMEPy provides an intuitive scripting interface, is easily compatible with a number of other Python packages, and is useful for educators and new designers.


Asunto(s)
Aprendizaje Profundo , Lenguajes de Programación , Programas Informáticos
2.
Can Assoc Radiol J ; 72(1): 150-158, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32755312

RESUMEN

STUDY PURPOSE: Morphometric methods categorize potential osteoporotic vertebral fractures (OVF) on the basis of loss of vertebral height. A particular example is the widely used semiquantitative morphometric tool proposed by Genant (GSQ). A newer morphologic algorithm-based qualitative (mABQ) tool focuses on vertebral end-plate damage in recognizing OVF. We used data from both sexes in the Canadian Multicentre Osteoporosis Study (CaMos) to compare the 2 methods in identifying OVF at baseline and during 10 years of follow-up. MATERIALS AND METHODS: We obtained lateral thoracic and lumbar spinal radiographs (T4-L4) 3 times, at 5-year intervals, in 828 participants of the population-based CaMos. Logistic regressions were used to study the association of 10-year changes in bone mineral density (BMD) with incident fractures. RESULTS: At baseline, 161 participants had grade 1 and 32 had grade 2 GSQ OVF; over the next 10 years, only 9 of these participants had sustained incident GSQ OVF. Contrastingly, 21 participants at baseline had grade 1 and 48 grade 2 mABQ events; over the next 10 years, 79 subjects experienced incident grade 1 or grade 2 mABQ events. Thus, incident grades 1 and 2 morphologic fractures were 8 times more common than morphometric deformities alone. Each 10-year decrease of 0.01 g/cm2 in total hip BMD was associated with a 4.1% (95% CI: 0.7-7.3) higher odds of having an incident vertebral fracture. CONCLUSIONS: This analysis further suggests that morphometric deformities and morphologic fractures constitute distinct entities; morphologic fractures conform more closely to the expected epidemiology of OVF.


Asunto(s)
Fracturas Osteoporóticas/diagnóstico por imagen , Radiografía/métodos , Fracturas de la Columna Vertebral/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Canadá , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radiología , Columna Vertebral/diagnóstico por imagen
4.
Public Health Res Pract ; 29(2)2019 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-31384888

RESUMEN

OBJECTIVES: Australia was one of the first countries to make the transition from cytology-based to HPV-based cervical screening.This analysis of the national program's transition to a new model looks at the lessons learnt that can provide valuable insights to other settings. Type of program: Australia's National Cervical Screening Program (NCSP). METHODS: Following an extensive policy review, in December 2017 the NCSP transitioned from 2-yearly cytology-based screening in women from age 18, to 5-yearly primary HPV screening from age 25. RESULTS: Some changes were more complex than initially anticipated. Building and implementing the National Cancer Screening Register was a more demanding and specialised project than expected. Regulatory requirements for self-collection were unexpectedly onerous, because self-collection was not formally included as an intended use by HPV test manufacturers. This delayed the rollout of a key measure to improve participation and equity. Colposcopy demand was expected to increase substantially but exceeded expectations. Uncertainty about appropriate clinical management or testing outside guideline recommendations may have contributed to the excess demand, highlighting the importance of training providers in the rationale for guidelines as well as the content. LESSONS LEARNT: Although the changes were evidence based, there were nevertheless some concerns among women and healthcare providers, especially about the longer interval and later starting age for screening. These could have been reduced through earlier and more extensively delivered information to healthcare providers, who play a key role in addressing community concerns. Improved coordination of stakeholder support between government and nongovernment organisations may also have extended both the reach and credibility of communication about the program changes. Transitioning a well-established program is challenging, not only because of the changes required, but also because the existing program must continue to function until the transition. Delays may be hard to avoid, but early communication will enable better forward planning, especially by service providers. Since delays can reduce wider confidence in the changes, proactive communication is critical. Achieving high and equitable screening coverage is a key element if Australia and other countries are to succeed in eliminating cervical cancer as a public health problem. Improving screening program confidence and participation remain important ongoing work. Lessons from Australia will provide valuable insights for other countries making similar changes.


Asunto(s)
Análisis Costo-Beneficio/estadística & datos numéricos , Detección Precoz del Cáncer/economía , Tamizaje Masivo/economía , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/economía , Adulto , Anciano , Anciano de 80 o más Años , Australia , Detección Precoz del Cáncer/estadística & datos numéricos , Femenino , Humanos , Persona de Mediana Edad
5.
Gynecol Oncol ; 152(3): 465-471, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30876490

RESUMEN

OBJECTIVE: Australia's HPV vaccination and HPV-based cervical screening programs are changing the landscape in cervical cancer prevention. We aim to identify areas which can make the biggest further impact on cervical cancer burden. This protocol describes the first stage of a program of work called Pathways-Cervix that aims to generate evidence from modelled evaluations of interventions across the cervical cancer spectrum. METHODS: Based on evidence from literature reviews and guidance from a multi-disciplinary Scientific Advisory Committee (SAC), the most relevant evaluations for prevention, diagnosis and treatment were identified. RESULTS: Priority evaluations agreed by the SAC included: increasing/decreasing and retaining vaccination uptake at the current level; vaccinating older women; increasing screening participation; methods for triaging HPV-positive women; improving the diagnosis of cervical intraepithelial neoplasia (CIN) and cancer; treating cervical abnormalities and cancer; and vaccinating women treated for CIN2/3 to prevent recurrence. Evaluations will be performed using a simulation model, Policy1-Cervix previously used to perform policy evaluations in Australia. Exploratory modelling of interventions using idealised scenarios will initially be conducted in single birth cohorts. If these have a significant impact on findings then evaluations with more realistic assumptions will be conducted. Promising strategies will be investigated further by multi-cohort simulations predicting health outcomes, resource use and cost outcomes. CONCLUSIONS: Pathways-Cervix will assess the relative benefits of strategies and treatment options in a systematic and health economic framework, producing a list of 'best buys' for future decision-making in cervical cancer control.


Asunto(s)
Erradicación de la Enfermedad/métodos , Modelos Teóricos , Neoplasias del Cuello Uterino/prevención & control , Adolescente , Adulto , Australia , Erradicación de la Enfermedad/normas , Detección Precoz del Cáncer , Femenino , Política de Salud , Humanos , Modelos Biológicos , Infecciones por Papillomavirus/prevención & control , Infecciones por Papillomavirus/transmisión , Infecciones por Papillomavirus/virología , Vacunas contra Papillomavirus/administración & dosificación , Neoplasias del Cuello Uterino/virología , Adulto Joven , Displasia del Cuello del Útero/prevención & control , Displasia del Cuello del Útero/virología
6.
J Bone Miner Res ; 34(3): 409-418, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30645770

RESUMEN

Until recently there has been little evidence available to validate any method by which to make an accurate diagnosis of an osteoporotic vertebral fractures (OVFs) from plain radiographs. In part this reflects a lack of a completely satisfactory "gold standard," but primarily it relates to the absence of well-designed prospective studies in this context. Historically, OVFs were recognized by evidence of macroscopic structural failure in vertebrae using the criteria applied elsewhere in the skeleton. This comprised altered alignment, fragmentation, cortical disruptions, and breaks, among other changes. However, these morphological criteria were replaced by vertebral morphometry, referring to the use of quantitative or quasi-quantitative measurement tools for fracture diagnosis. Vertebral morphometry emerged as an understanding of and treatment for osteoporosis evolved, mainly in response to the need for expeditious assessments of large numbers of spine images for epidemiological and pharmaceutical purposes. Although most of the descriptions of such morphometric tools have stressed that they were not to be applied to clinical diagnosis with respect to individual patients, this constraint has been widely disregarded. Here we review the major attempts to develop a diagnostic strategy for OVF and describe their characteristics in adults and children. Recent evidence suggests that morphometric (quantitative; ie, based on measurement of dimensions and shape description) criteria are inferior to morphologic (qualitative; ie, based on structural integrity) vertebral damage assessment in identifying people with low bone density and at an increased risk of future fracture. Thus there is now an evidentiary basis for suggesting that morphological assessment is the preferred strategy for use in diagnosing OVF from radiographs. © 2019 American Society for Bone and Mineral Research.


Asunto(s)
Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas de la Columna Vertebral/diagnóstico por imagen , Niño , Humanos , Fracturas Osteoporóticas/diagnóstico , Fracturas Osteoporóticas/patología , Fracturas de la Columna Vertebral/diagnóstico , Fracturas de la Columna Vertebral/patología
11.
Lancet Public Health ; 2(2): e96-e107, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-29253402

RESUMEN

BACKGROUND: Australia's National Cervical Screening Program currently recommends cytological screening every 2 years for women aged 18-69 years. Human papillomavirus (HPV) vaccination was implemented in 2007 with high population coverage, and falls in high-grade lesions in young women have been reported extensively. This decline prompted a major review of the National Cervical Screening Program and new clinical management guidelines, for which we undertook this analysis. METHODS: We did effectiveness modelling and an economic assessment of potential new screening strategies, using a model of HPV transmission, vaccination, natural history, and cervical screening. First, we evaluated 132 screening strategies, including those based on cytology and primary HPV testing. Second, after a recommendation was made to adopt primary HPV screening with partial genotyping and direct referral to colposcopy of women positive for HPV16/18, we evaluated the final effect of HPV screening after incorporating new clinical guidelines for women positive for HPV. Both evaluations considered both unvaccinated and vaccinated cohorts. FINDINGS: Strategies entailing HPV testing every 5 years and either partial genotyping for HPV16/18 or cytological co-testing were the most effective. One of the most effective and cost-effective strategies comprised primary HPV screening with referral of women positive for oncogenic HPV16/18 direct to colposcopy, with reflex cytological triage for women with other oncogenic types and direct referral for those in this group with high-grade cytological findings. After incorporating detailed clinical guidelines recommendations, this strategy is predicted to reduce cervical cancer incidence and mortality by 31% and 36%, respectively, in unvaccinated cohorts, and by 24% and 29%, respectively, in cohorts offered vaccination. Furthermore, this strategy is predicted to reduce costs by up to 19% for unvaccinated cohorts and 26% for cohorts offered vaccination, compared with the current programme. INTERPRETATION: Primary HPV screening every 5 years with partial genotyping is predicted to be substantially more effective and potentially cost-saving compared with the current cytology-based screening programme undertaken every 2 years. These findings underpin the decision to transition to primary HPV screening with partial genotyping in the Australian National Cervical Screening Program, which will occur in May, 2017. FUNDING: Department of Health, Australia.


Asunto(s)
Detección Precoz del Cáncer/economía , Detección Precoz del Cáncer/métodos , Infecciones por Papillomavirus/diagnóstico , Vacunas contra Papillomavirus/administración & dosificación , Neoplasias del Cuello Uterino/diagnóstico , Adolescente , Adulto , Anciano , Australia , Biología Celular/economía , Análisis Costo-Beneficio , Pruebas Diagnósticas de Rutina/economía , Femenino , Humanos , Persona de Mediana Edad , Infecciones por Papillomavirus/prevención & control , Prevención Primaria/economía , Evaluación de Programas y Proyectos de Salud , Adulto Joven
13.
AJR Am J Roentgenol ; 209(6): W382-W387, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28929807

RESUMEN

OBJECTIVE: The purpose of this study was to compare the efficacy of gelatin sponge with that of coils for splenic artery embolization in the treatment of blunt splenic injury. MATERIALS AND METHODS: A single-center retrospective review was performed with the records of 63 patients (45 men, 18 women; mean age, 45.5 years; range, 16-84 years) with blunt splenic injury treated at a tertiary care trauma center by splenic artery embolization with gelatin sponge (n = 30 patients) or metallic coils (n = 33 patients) between 2005 and 2014. The two groups had comparable median American Association for the Surgery of Trauma grades of IV and comparable angiographic appearances regarding active extravasation and pseudoaneurysm formation at preembolization splenic arteriography (p = 0.32). Clinical outcomes and procedure-related outcomes were evaluated. RESULTS: The success rates were similar in the two groups: splenic artery embolization failed in 6.6% (2/30) of patients in the gelatin sponge group and 12.1% (4/33) in the coil embolization group (p = 0.45; 95% CI, -30.1% to 19.2%). Major complications occurred in six patients (20.0%) in the gelatin sponge group and in six patients (18.1%) in the coil group (p = 0.85; 95% CI, -23.0% to 26.6%). Minor complications occurred in three patients (10.0%) in the gelatin sponge group and seven patients (21.2%) in the coil group (p = 0.21; 95% CI, -35.4% to 14.0%). Procedure time was significantly shorter in the gelatin sponge group (median, 32 minutes; interquartile range, 18-48 minutes) than in the coil group (median, 53 minutes; interquartile range, 30-76 minutes) (p = 0.01). CONCLUSION: Splenic artery embolization with gelatin sponge appears to be as effective and as safe as coil embolization and can be completed in a shorter time.


Asunto(s)
Embolización Terapéutica/métodos , Gelatina/uso terapéutico , Bazo/lesiones , Arteria Esplénica , Heridas no Penetrantes/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Embolización Terapéutica/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
16.
Aust N Z J Obstet Gynaecol ; 57(4): 469-472, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28580578

RESUMEN

INTRODUCTION: The current Australian National Cervical Screening Program (NCSP) involves biennial, cytology-based screening of women from the age of 18 years. From December, 2017 this will change to a five-yearly human papilloma virus-based screening commencing at age 25. There is some concern that the new program may delay the opportunistic detection of cervical cancers in women under 25 years. AIM: (1) To review all cases of invasive cervical cancer in Queensland women under the age of 25 over the last 28 years. (2) To determine symptoms and screening history prior to diagnosis. METHODS: A retrospective cohort study was undertaken at the Queensland Centre for Gynaecological Cancer (QCGC) and the Queensland Cancer Registry (QCR) of all women aged between 13 and 25 years diagnosed with cervical cancer in Queensland between 1984 and 2012. Demographic data and symptoms prior to diagnosis were extracted from the QCGC and QCR databases. RESULTS: A total of 56 women aged 13-25, were diagnosed with cervical cancer and treated at the QCGC between 1984 and 2012. The commonest reason for the diagnosis of cancer was investigation of abnormal symptoms (n = 22, 39%) rather than routine Pap smear abnormalities (n = 15, 26%). CONCLUSIONS: Consistent with the world literature, there is a very low incidence of cervical cancer in women under 25 years of age, irrespective of the age of commencement of screening, or the screening interval. Our study lends some support to the proposed commencement age of 25 years in the new NCSP.


Asunto(s)
Neoplasias del Cuello Uterino/diagnóstico , Adenocarcinoma/diagnóstico , Adenocarcinoma/epidemiología , Adenocarcinoma/patología , Adolescente , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Femenino , Humanos , Estadificación de Neoplasias , Queensland/epidemiología , Estudios Retrospectivos , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/patología , Adulto Joven
18.
BMC Nephrol ; 18(1): 129, 2017 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-28385153

RESUMEN

BACKGROUND: Coronary artery calcification (CAC) is highly prevalent among dialysis patients and is associated with increased cardiovascular and all cause mortality. Magnesium (Mg) inhibits vascular calcification in animal and in-vitro studies but whether the same effect occurs in humans is uncertain. METHODS: A single centre cross-sectional study of 80 prevalent peritoneal dialysis (PD) patients; on PD only for a minimum of 3 months. A radiologist blinded to patient status calculated their abdominal aortic calcification (AAC) scores on lateral lumbar spine radiographs, a validated surrogate for CAC. RESULTS: Eighty patients provided informed consent and underwent lumbar spine radiography. The mean serum Mg was 0.8 mmol/L (standard deviation 0.2) and mean AAC score 8.9 (minimum 0, maximum 24). A higher serum Mg level was associated with a lower AAC score (R 2 = 0.06, unstandardized coefficient [B] = -7.81, p = 0.03), and remained after adjustment for age, serum phosphate, serum parathyroid hormone, low-density lipoprotein cholesterol, smoking history, and diabetes (model adjusted R 2 = 0.36, serum Mg and AAC score B = -11.44, p = 0.00). This translates to a 0.1 mmol/L increase in serum Mg being independently associated with a 1.1-point decrease in AAC score. CONCLUSIONS: Our findings suggest that Mg may inhibit vascular calcification. If this association is replicated across larger studies with serial Mg and vascular calcification measurements, interventions that increase serum Mg and their effect on vascular calcification warrant further investigation in the PD population.


Asunto(s)
Enfermedades de la Aorta/sangre , Fallo Renal Crónico/terapia , Magnesio/sangre , Diálisis Peritoneal , Calcificación Vascular/sangre , Anciano , Aorta Abdominal/diagnóstico por imagen , Enfermedades de la Aorta/diagnóstico por imagen , Enfermedades de la Aorta/epidemiología , LDL-Colesterol/sangre , Estudios Transversales , Femenino , Humanos , Fallo Renal Crónico/epidemiología , Masculino , Persona de Mediana Edad , Ontario/epidemiología , Hormona Paratiroidea/sangre , Radiografía , Factores de Riesgo , Calcificación Vascular/diagnóstico por imagen , Calcificación Vascular/epidemiología
20.
JAMA ; 317(12): 1224-1233, 2017 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-28350928

RESUMEN

Importance: Standard treatment for endometrial cancer involves removal of the uterus, tubes, ovaries, and lymph nodes. Few randomized trials have compared disease-free survival outcomes for surgical approaches. Objective: To investigate whether total laparoscopic hysterectomy (TLH) is equivalent to total abdominal hysterectomy (TAH) in women with treatment-naive endometrial cancer. Design, Setting, and Participants: The Laparoscopic Approach to Cancer of the Endometrium (LACE) trial was a multinational, randomized equivalence trial conducted between October 7, 2005, and June 30, 2010, in which 27 surgeons from 20 tertiary gynecological cancer centers in Australia, New Zealand, and Hong Kong randomized 760 women with stage I endometrioid endometrial cancer to either TLH or TAH. Follow-up ended on March 3, 2016. Interventions: Patients were randomly assigned to undergo TAH (n = 353) or TLH (n = 407). Main Outcomes and Measures: The primary outcome was disease-free survival, which was measured as the interval between surgery and the date of first recurrence, including disease progression or the development of a new primary cancer or death assessed at 4.5 years after randomization. The prespecified equivalence margin was 7% or less. Secondary outcomes included recurrence of endometrial cancer and overall survival. Results: Patients were followed up for a median of 4.5 years. Of 760 patients who were randomized (mean age, 63 years), 679 (89%) completed the trial. At 4.5 years of follow-up, disease-free survival was 81.3% in the TAH group and 81.6% in the TLH group. The disease-free survival rate difference was 0.3% (favoring TLH; 95% CI, -5.5% to 6.1%; P = .007), meeting criteria for equivalence. There was no statistically significant between-group difference in recurrence of endometrial cancer (28/353 in TAH group [7.9%] vs 33/407 in TLH group [8.1%]; risk difference, 0.2% [95% CI, -3.7% to 4.0%]; P = .93) or in overall survival (24/353 in TAH group [6.8%] vs 30/407 in TLH group [7.4%]; risk difference, 0.6% [95% CI, -3.0% to 4.2%]; P = .76). Conclusions and Relevance: Among women with stage I endometrial cancer, the use of total abdominal hysterectomy compared with total laparoscopic hysterectomy resulted in equivalent disease-free survival at 4.5 years and no difference in overall survival. These findings support the use of laparoscopic hysterectomy for women with stage I endometrial cancer. Trial Registration: clinicaltrials.gov Identifier: NCT00096408; Australian New Zealand Clinical Trials Registry: CTRN12606000261516.


Asunto(s)
Neoplasias Endometriales/cirugía , Histerectomía/métodos , Laparoscopía , Anciano , Australia , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Neoplasias Endometriales/mortalidad , Neoplasias Endometriales/patología , Femenino , Estudios de Seguimiento , Hong Kong , Humanos , Histerectomía/mortalidad , Análisis de Intención de Tratar , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Siembra Neoplásica , Neoplasias Primarias Secundarias , Nueva Zelanda , Factores de Tiempo
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