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1.
BMC Health Serv Res ; 21(1): 909, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479565

RESUMO

BACKGROUND: To evaluate the cost-effectiveness of six diagnostic strategies involving magnetic resonance imaging (MRI) targeted biopsy for diagnosing prostate cancer in initial and repeat biopsy settings from the Singapore healthcare system perspective. METHODS: A combined decision tree and Markov model was developed. The starting model population was men with mean age of 65 years referred for a first prostate biopsy due to clinical suspicion of prostate cancer. The six diagnostic strategies were selected for their relevance to local clinical practice. They comprised MRI targeted biopsy following a positive pre-biopsy multiparametric MRI (mpMRI) [Prostate Imaging - Reporting and Data System (PI-RADS) score ≥ 3], systematic biopsy, or saturation biopsy employed in different testing combinations and sequences. Deterministic base case analyses with sensitivity analyses were performed using costs from the healthcare system perspective and quality-adjusted life years (QALY) gained as the outcome measure to yield incremental cost-effectiveness ratios (ICERs). RESULTS: Deterministic base case analyses showed that Strategy 1 (MRI targeted biopsy alone), Strategy 2 (MRI targeted biopsy ➔ systematic biopsy), and Strategy 4 (MRI targeted biopsy ➔ systematic biopsy ➔ saturation biopsy) were cost-effective options at a willingness-to-pay (WTP) threshold of US$20,000, with ICERs ranging from US$18,975 to US$19,458. Strategies involving MRI targeted biopsy in the repeat biopsy setting were dominated. Sensitivity analyses found the ICERs were affected mostly by changes to the annual discounting rate and prevalence of prostate cancer in men referred for first biopsy, ranging between US$15,755 to US$23,022. Probabilistic sensitivity analyses confirmed Strategy 1 to be the least costly, and Strategies 2 and 4 being the preferred strategies when WTP thresholds were US$20,000 and US$30,000, respectively. LIMITATIONS AND CONCLUSIONS: This study found MRI targeted biopsy to be cost-effective in diagnosing prostate cancer in the biopsy-naïve setting in Singapore.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias da Próstata , Idoso , Biópsia , Análise Custo-Benefício , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Singapura/epidemiologia
2.
J Am Coll Radiol ; 17(6): 717-723, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32298643

RESUMO

As coronavirus disease 2019 (COVID-19) infection spreads globally, the demand for chest imaging will inevitably rise with an accompanying increase in risk of disease transmission to frontline radiology staff. Radiology departments should implement strict infection control measures and robust operational plans to minimize disease transmission and mitigate potential impact of possible staff infection. In this article, the authors share several operational guidelines and strategies implemented in our practice to reduce spread of COVID-19 and maintain clinical and educational needs of a teaching hospital.


Assuntos
Controle de Doenças Transmissíveis/organização & administração , Infecções por Coronavirus/prevenção & controle , Controle de Infecções/organização & administração , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Pandemias/estatística & dados numéricos , Pneumonia Viral/prevenção & controle , Serviço Hospitalar de Radiologia/organização & administração , COVID-19 , Infecções por Coronavirus/diagnóstico por imagem , Infecção Hospitalar/prevenção & controle , Surtos de Doenças/prevenção & controle , Surtos de Doenças/estatística & dados numéricos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Saúde do Trabalhador , Inovação Organizacional , Avaliação de Resultados em Cuidados de Saúde , Pandemias/prevenção & controle , Pneumonia Viral/diagnóstico por imagem , Singapura , Tomografia Computadorizada por Raios X/métodos
3.
ANZ J Surg ; 88(6): E498-E502, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28803449

RESUMO

BACKGROUND: Diffusion-weighted (DW) imaging is a functional magnetic resonance imaging (MRI) technique that detects lesions with high cellularity, such as malignant tumours. This prospective study was performed to compare the accuracy of DW-MRI with multidetector computed tomography (MDCT) in staging of colorectal cancer. METHODS: Thirty patients with histologically proven colorectal cancer were prospectively recruited. Each patient underwent both MDCT and DW-MRI of the abdomen-pelvis for primary staging. Images were evaluated for nodal and distant metastases. The reference standard was histopathological findings for nodal involvement and surveillance imaging for suspected hepatic metastases. RESULTS: The primary cancers were located in the rectum (n = 16, 53.3%), sigmoid colon (n = 9, 30%) and right colon (n = 5, 16.6%). For nodal metastases, the sensitivity and specificity of DW-MRI were 84.6% (95% confidence interval (CI): 54.6-98.1%) and 20.0% (95% CI: 2.5-55.6%) compared with 84.6% (95% CI: 54.6-98.1%) and 40.0% (95% CI: 12.2-73.8%) for MDCT. For liver metastases, the sensitivity and specificity for DW-MRI were 100.0% (95% CI: 63.1-100.0%) and 100% (95% CI: 84.6-100%) compared with 87.5% (95% CI: 47.4-99.7%) and 95.5% (95% CI: 77.2-99.9%) for MDCT. DW imaging altered the clinical management in three (10.0%) patients by detecting missed hepatic metastases in two patients and accurately diagnosing another patient with a hepatic cyst, mistaken for metastasis on MDCT. CONCLUSION: DW-MRI is more accurate for detecting hepatic metastases in colorectal cancer compared with MDCT.


Assuntos
Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Tomografia Computadorizada Multidetectores/métodos , Estudos de Coortes , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Masculino , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Cuidados Pré-Operatórios/métodos , Estudos Prospectivos , Sensibilidade e Especificidade
4.
Acad Radiol ; 21(4): 531-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24594423

RESUMO

RATIONALE AND OBJECTIVES: Diffusion-weighted imaging (DWI) of the pelvis at 3T is prone to artifacts that diminish the image quality. Readout-segmented echo-planar imaging (RS-EPI) is a new DWI technique that can reduce the artifacts associated with standard single-shot echo-planar imaging (SS-EPI) DWI. The purpose of this study was to evaluate the feasibility and image quality of RS-EPI in pelvic DWI compared to SS-EPI on a 3T imaging system. MATERIALS AND METHODS: Thirty patients underwent pelvic DWI on a 3T scanner with SS-EPI and RS-EPI techniques. Two blinded readers independently assessed each set of images for geometric distortion, image blurring, ghosting artifacts, lesion conspicuity, and overall image quality on a 7-point scale. Qualitative image scores were compared using paired Wilcoxon signed rank test. Interreader correlation was assessed by Spearman rank correlation. RESULTS: Geometric distortion, imaging blurring, ghosting artifacts, lesion conspicuity, and overall image quality were rated significantly better by both readers for RS-EPI technique (P < .01 for all parameters). There was moderate-high correlation between the readers (r = 0.649-0.752) for all parameters apart from lesion conspicuity (r = 0.351). Both readers preferred the RS-EPI set of DWI images in most of the cases (reader 1: 0.87, 95% CI 0.74-0.99; reader 2: 0.77, 95% CI 0.61-0.93). Mean difference and limits of agreement between apparent diffusion coefficient (ADC) values obtained from the two methods were 0.01 (-0.08, 0.10) × 10(-3) mm(2)/s. CONCLUSIONS: RS-EPI DWI images showed improved image quality compared to SS-EPI technique at 3T. RS-EPI is a feasible technique in the pelvis for producing high-resolution DWI.


Assuntos
Artefatos , Imagem de Difusão por Ressonância Magnética/métodos , Imagem Ecoplanar/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Pélvicas/patologia , Pelve/patologia , Adulto , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Método Simples-Cego , Adulto Jovem
5.
J Magn Reson Imaging ; 39(1): 1-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24123300

RESUMO

PURPOSE: To determine normal liver stiffness values evaluated with magnetic resonance elastography (MRE) in healthy normal Asian volunteers and assess its reproducibility. MATERIALS AND METHODS: Liver stiffness was evaluated with MRE in 41 healthy Asians (23 females, 18 males; mean age, 41.8 years, and mean body mass index [BMI], 23.4 kg/m(2) ) on a 1.5T clinical scanner. The correlations between mean liver stiffness and age, gender, BMI, and fat fraction percentage of the liver were studied. Another 12 volunteers underwent liver MRE exams on two separate days 4-6 weeks apart under similar conditions for reproducibility assessment. Intraclass correlation coefficient (ICC) analysis was performed and within-subject coefficient of variation (CV) of stiffness was estimated. RESULTS: The mean ± standard deviation (SD) of liver stiffness in normal healthy Asian subjects was 2.09 ± 0.22 kPa (95% confidence interval [CI], 2.04-2.15 kPa; range 1.68-2.48 kPa). The mean liver stiffness did not significantly correlate with age, gender, BMI, or fat content of the liver. The ICC for mean liver stiffness was 0.90 (95% CI, 0.78-0.96) and CV ranged from 2.2%-11.4%. CONCLUSION: The liver stiffness in normal Asians is not affected by age, gender, BMI, or fat content. Liver stiffness with MRE is highly reproducible.


Assuntos
Técnicas de Imagem por Elasticidade , Fígado/patologia , Adulto , Grupo com Ancestrais do Continente Asiático , Índice de Massa Corporal , Módulo de Elasticidade , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes
7.
Cancer Imaging ; 12: 290-303, 2012 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-23033451

RESUMO

The role of imaging in the management of rectal malignancy has progressively evolved and undergone several paradigm shifts. Unlike a few decades ago when the role of a radiologist was restricted at defining the longitudinal extent of the tumour with barium enema, recent advances in imaging techniques permit highly accurate locoregional and distant staging of the disease as well as prognostication on those who are likely to have a postoperative recurrence. Computed tomography (CT) has always been the mainstay of imaging when evaluating for distant metastasis, with the advent of positron emission tomography/CT improving its specificity. In rectal malignancy, it is the local extent of the disease that often influences the surgical decision making and need for neoadjuvant therapy. Although endoscopic ultrasound has been the traditional technique for determining the depth of tumour invasion, over the last decade magnetic resonance imaging (MRI) has emerged as a very effective tool for accurate T-staging. This review intends to address the status of various imaging modalities and their advantages and limitations in detection, pretreatment staging, and assessment of therapeutic efficacy in rectal cancer, with emphasis on MRI of high spatial resolution.


Assuntos
Neoplasias Retais/diagnóstico , Endossonografia , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Metástase Linfática , Imageamento por Ressonância Magnética , Imagem Multimodal , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons , Neoplasias Retais/patologia , Reto/anatomia & histologia , Tomografia Computadorizada por Raios X
9.
Thorac Cancer ; 2(2): 54-60, 2011 05.
Artigo em Inglês | MEDLINE | ID: mdl-27755811

RESUMO

BACKGROUND: There is emerging evidence that bronchioloalveolar carcinoma (BAC) is the forerunner of peripheral adenocarcinoma lung cancers (ALC). Since advanced stage ALC is often diagnosed on cytology alone, we hypothesized that the incidence of BAC is underreported and that a large proportion of ALC in our population are part of the BAC-adenocarcinoma sequence. METHODS: We reviewed the pretreatment computed tomographic (CT) scans of 69 patients with ALC and looked for characteristic features of BAC. RESULTS: The median patient age was 63, and the majority were of Chinese descent (75.4%). Women comprised 43.5% of the patients (30 patients) and never-smokers comprised 47.8% (33 patients). Only 15 patients (21.7%) had surgical specimens. The presence of BAC components was reported in the pathology of 16 patients (23.2%). CT features classically associated with BAC were found in 35 patients (50.7%). These included air bronchograms or bubble-like lucencies in 24 patients (34.8%), ground-glass opacities in 19 (27.5%), consolidation or pneumonic picture in 11 (15.9%), diffuse small or miliary nodules in 10 (14.5%), and the CT angiogram sign in 4 (5.8%). CONCLUSIONS: We found provocative radiologic evidence that a large proportion of our ALC cases arise from BAC. The CT findings are consistent with current understanding of the likely pathogenesis of peripheral ALC.

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