China
Africa
Explore chapters and articles related to this topic
Thermal Imaging in Detection of Fever for Infectious Diseases
Published in U. Snekhalatha, K. Palani Thanaraj, Kurt Ammer, Artificial Intelligence-Based Infrared Thermal Image Processing and Its Applications, 2023
U. Snekhalatha, K. Palani Thanaraj, Kurt Ammer
It is important to remind the reader that screening and diagnosing are two different procedures. Nicholas J. Wald gave the following definition (1994): “Screening is the systematic application of a test or enquiry to identify individuals at sufficient risk of a specific disorder to warrant further investigation or direct preventive action, amongst persons who have not sought medical attention on account of symptoms of that disorder.” Subjects who proved positive in a screening test must be confirmed as positive cases by a standard diagnostic test. Threshold values for positive cases depend on the applied method of measurement. While the threshold for fever is 38°C for rectal temperature (Niehues, 2013), 37.7°C was reported for oral temperature (Mackowiak, Wasserman, and Levine 1992), and 37.8°C for ear temperature (Cho and Yoon, 2014). The difference of oral and ear temperature to rectal temperature builds the rationale for different fever thresholds. The selection of the threshold for screening should be determined by the rate of false-negative cases.
23Na
Published in Guillaume Madelin, X-Nuclei Magnetic Resonance Imaging, 2022
Treatments for breast cancer such as prophylactic mastectomy or chemoprevention are more effective when the disease is detected at an early stage. Mammography is the standard method for breast cancer screening [123] with high specificity (>90%) but has a very variable sensitivity (30–60%) due to difficult lesion detection in dense breast tissue [124–126]. Ultrasound (US) is a supplemental method for women with high-risk and dense breast tissue that can increase screening sensitivity, but can also lead to higher false-positive rates [127]. Standard proton MRI has a higher sensitivity (75–90%) and is less affected by the breast tissue density, but has lower specificity (70–90%) [124, 127]. False-positive diagnoses from these screening methods result in increased patient anxiety, overdiagnosis and unnecessary biopsy, or overtreatment [128]. Dynamic contrast-enhanced MRI (DCE-MRI) is the most sensitive MRI method to detect breast cancer and assess tumor size, with a good specificity, and can provide to some extent functional information about tumor perfusion and vascularity. Other 1H MR techniques such as DWI, PWI and MRS can also be added to the scan protocol to provide more specific information about the hallmarks of cancer as a multiparametric MRI method [129], and improve sensitivity and specificity of breast cancer detection and therapy assessment.
Hypertension and Correlation to Cerebrovascular Change: A Brief Overview
Published in Ayman El-Baz, Jasjit S. Suri, Cardiovascular Imaging and Image Analysis, 2018
Heba Kandil, Dawn Sosnin, Ali Mahmoud, Ahmed Shalaby, Ahmed Soliman, Adel Elmaghraby, Jasjit S. Suri, Guruprasad Giridharan, Ayman El-Baz
Many of the tests used by mainstream medicine are excellent at detecting disease and are very useful for identifying specific disease processes. However, most of them identify disease processes at later stages where most of the damage might not be reversed [9]. While antihypertensive treatment can slow the progression of the disease and its effects, detection and efforts to slow or halt its development earlier in the disease course are desired to reduce risk and improve patient quality of life [9], [67], [68]. Thus, there is a need for automatic computerized systems that are capable of providing accurate screening and diagnoses for early detection of prehypertension for prolonging life and improving patients' quality of life. These automatic systems may help identify hypertension many years before its onset compared to current testing methods. Screening and early diagnosis gives patients, families, and providers the opportunity to take steps to prevent or delay the onset of the disease process, or to limit the severity of symptoms and sequelae, improving patient-oriented outcomes.
Adaptive risk-based pooling in public health screening
Published in IISE Transactions, 2018
Hrayer Aprahamian, Ebru K. Bish, Douglas R. Bish
Screening for diseases is an important, and extensively used, public health tool. The classification problem (i.e., classifying each subject as positive versus negative for a disease) involves testing a large number of subjects for infectious or genetic diseases through in vitro laboratory tests performed on specimens (e.g., blood, urine, tissue swabs) from the subjects to measure the concentration (load) of a disease-related bio-marker. Public health screening is performed when early detection can improve clinical outcomes and/or to reduce the spread of infectious diseases, especially for diseases that have slow-to-develop and/or initially non-specific symptoms (e.g., AIDS, Zika, hepatitis) and can save lives, reduce suffering, and decrease healthcare expenditures. However, due to limited resources, efficiency is essential. As screening usually involves large populations and diseases with low prevalence rates, pooled testing (testing combined specimens from multiple subjects via a single test) is commonly used to improve the efficiency of screening efforts. Pooling schemes studied in the literature test each specimen multiple times, as only a small sample from the collected specimen is required for a test; therefore, multiple tier schemes—i.e., two- or three-tier schemes—are common, in order to increase the classification accuracy of the schemes.
Analyzing overdiagnosis risk in cancer screening: A case of screening mammography for breast cancer
Published in IISE Transactions on Healthcare Systems Engineering, 2018
Mahboubeh Madadi, Mohammadhossein Heydari, Shengfan Zhang, Edward Pohl, Chase Rainwater, Donna L. Williams
Preventive health services with advanced technologies, although known to detect diseases in early stages when patients are more likely to be successfully treated, have ignited a debate on overdiagnosis. Ideally, screening interventions aim to detect diseases that will ultimately cause harm, and the purpose of screening interventions is to advance the detection time, when the disease is in its early stages and is more likely to be treated. However, there is always the risk of overdiagnosis and overtreatment when detecting a disease in its early stages. Overdiagnosis of a disease is defined as the diagnosis of an asymptomatic disease having no signs or symptoms, which would have never become symptomatic during an individual's remaining lifetime.
Optimal population screening policies for Alzheimer’s disease*
Published in IISE Transactions on Healthcare Systems Engineering, 2019
Zehra Önen, Serpil Sayin, Ibrahim Hakan Gürvit
Screening tests aim to sort out individuals who probably have a disease from those who probably do not (World Health Organization, 2012). In general, screening tests may generate false positives and false negatives with a certain likelihood. A screening policy is expected to balance the trade-off between the benefits of early intervention and risks of unnecessary screening test applications and implications of false positives. Currently, there are no population screening policies in any country for AD, although its importance has been stated at various occasions, such as in the Leon Thal Symposium series (Khachaturian et al., 2010, 2011) and the National Alzheimer’s Project Act (NAPA) in the United States (Khachaturian et al., 2012). The government proposal in the UK for screening the elderly population for dementia during their routine health checks set off a discussion among health professionals who are in favor and those who are against such a policy (Kmietowicz, 2012). In January 2015, the UK National Screening Committee upheld its recommendation against screening everyone aged 65 and over for dementia. Their decision was mainly based on poor accuracy of the suggested cognitive test and lack of a cure (UK National Screening Committee, 2015). A survey-based study conducted in 2009 in multiple European countries found that a smaller proportion of physicians (42%) and payers (44%) than members of the general public (81%) or caregivers (80%) agreed that a routine screening for AD starting at age 65 would be beneficial (Bond et al., 2010). Participants who were not in favor of screening cited reasons such as the inaccuracy of available tests, high costs, absence of cure, negative impact on the individual and late visibility of symptoms in AD.