A novel method of noise reduction has been tested for mammography using computer-simulated images for which the truth is known exactly. This method is based on comparing two images. The images are compared at different scales, using a cross-correlation function as a measure of similarity to define the image modifications in the wavelet domain. The computer-simulated images were calculated for n...

PURPOSE To assess the noise characteristics of the new adaptive statistical iterative reconstruction (ASiR-V) in comparison to ASiR. METHODS A water phantom was acquired with common clinical scanning parameters, at five different levels of CTDIvol . Images were reconstructed with different kernels (STD, SOFT, and BONE), different IR levels (40%, 60%, and 100%) and different slice thickness (S...

background: natural background radiation of a particular region is one of the distinctive factors defining the status of environment. eloor island is an industrial area in ernakulum district of the state of kerala, india. the indoor and outdoor gamma level measurements have been carried out for the region for evaluating the annual effective dose to the population residing in this area. material...

Noise-induced hearing loss is the most prevalent occupational injury in the United States despite the adoption of clear permissible exposure limits and protocols for hearing conservation. This study identifies low-level chemical asphyxiant exposure as a risk factor capable of potentiating noise-induced hearing loss. Rats were exposed to 10, 30, and 50 ppm hydrogen cyanide (HCN) alone for 3.5 h ...

Dynamic computed tomography perfusion (CTP) imaging is a promising approach for acute ischemic stroke diagnosis and evaluation. Hemodynamic parametric maps of cerebral parenchyma are calculated from repeated CT scans the first pass iodinated contrast through brain. It necessary to reduce dose CTP routine applications due high radiation exposure scans, where image denoising achieve reliable diag...

OBJECTIVES This cross-sectional study was performed in the Dental School of Prince of Songkla University to ascertain noise exposure of dentists, dental assistants, and laboratory technicians. A noise spectral analysis was taken to illustrate the spectra of dental devices. METHODS A noise evaluation was performed to measure the noise level at dental clinics and one dental laboratory from May ...

In Computed Tomography (CT), image quality is often quantified by the measuring the amount of noise (SD) in the image in relation to the spatial resolution (lp/cm). The simplest way to influence the amount of image noise is with the selection of a specific convolution filter in the reconstruction process. Selecting a “smooth” convolution filter will reduce image noise; however, it will also smo...

The increased use of computed tomography (CT) and its high radiation dose have led to great concerns about its potential for radiation induced cancer risks. Breast is a radiosensitive tissue based on tissue weighting factors assigned by the International Commission on Radiological Protection (ICRP). Moreover, the dose is maximal on the surface of the patient. Therefore, strategies should be tak...

Background: Children have a potential risk from radiation exposure because they are more sensitive to than adults. Objective: The purpose of this work is estimate image quality according tube voltage (kV) and dose in pediatric computed tomography (CT) using deep learning reconstruction (DLR). Methods: Phantom images children adults were obtained for kV, dose, methods. CT emits fan beam the oppo...