simultaneous exposure of highly-used chemical and physical agents are expected to happen in many occupations. in the present study the impact of simultaneous exposure to noise and formaldehyde on oxidative stress in blood and liver tissue of rat was investigated. animal study was conducted in the school of public health, shahid beheshti university of medical scineces, tehran, iran in 2013. a to...

OBJECTIVE To evaluate noise reduction and image quality improvement in low-radiation dose chest CT images in children using adaptive statistical iterative reconstruction (ASIR) and a full model-based iterative reconstruction (MBIR) algorithm. METHODS Forty-five children (age ranging from 28 days to 6 years, median of 1.8 years) who received low-dose chest CT scans were included. Age-dependent...

OBJECTIVE This systematic review aimed to explore the evidence on whether the preferred listening levels (PLLs) and durations of music listening through personal listening devices (PLDs) in adolescents and young adults exceed the current recommended 100% daily noise dose; together with the impact on hearing and possible influential factors of such listening behaviours. DESIGN A systematic sea...

BACKGROUND AND PURPOSE While CT has found wide use in medical practice, it is also a substantial source of radiation exposure and is associated with an increased lifetime risk of cancer. There is an urgent need for new approaches to reduce the radiation dose in CT. In this regard, ASIR is an alternative method to FBP. We assessed the effect of ASIR on dose reduction in adult head CT. MATERIAL...

Computed tomography angiography (CTA) of carotid arteries and vertebrobasilar system is a standardized procedure with excellent image quality, but radiation exposure remains a matter of concern. The aim of this study is to examine to what extent radiation dose can be lowered in relation to a standard protocol by simulating examinations with lower tube currents applying a dedicated software.Lowe...

Purpose Despite the indispensable role of x-ray computed tomography (CT) in diagnostic medicine, associated harmful ionizing radiation dose is a major concern, as it may cause genetic diseases and cancer. Decreasing patients’ exposure can reduce hence related risks, but would inevitably induce higher quantum noise. Supervised deep learning techniques have been used to train neural networks for ...

OBJECTIVE To evaluate the image quality and radiation dose of indirect computed tomographic venography (CTV) using 80 kVp with sinogram-affirmed iterative reconstruction (SAFIRE) and 120 kVp with filtered back projection (FBP). MATERIALS AND METHODS This retrospective study was approved by our institution and informed consent was waived. Sixty-one consecutive patients (M: F = 27: 34, mean age...

Purpose Four-dimensional computed tomography (CT) images are typically used to quantify the necessary internal target volumes for thoracic and abdominal tumors. However, 4-dimensional CT is typically associated with excessive imaging dose to patients and the situation is exacerbated when using repeat 4-dimensional CT imaging on a weekly or daily basis throughout fractionated therapy. The aim of...

Abstract Generative adversarial network (GAN) has been applied for low-dose CT images to predict normal-dose images. However, the undesired artifacts and details bring uncertainty clinical diagnosis. In order improve visual quality while suppressing noise, in this paper, we mainly studied two key components of deep learning based (LDCT) restoration models—network architecture loss, proposed a d...

A reduction of the radiation dose in computed tomography typically leads to more noise in the acquired projections. Here filtering methods can help to reduce the noise level and preserve the diagnostic value of the low-dose images. In this work, six variants of Gaussian and bilateral filters are applied in both projection and reconstruction domain. Our comparison of noise reduction and image re...