PURPOSE To compare four metal-artifact-reduction (MAR) algorithms in their ability to correct the typical streaking artifacts that appear in cone- beam computed tomography (CBCT) images. METHODS The goal was to compare the strengths and weaknesses of four MAR algorithms, Basic; Wei; Mazin and Meyer, using typical clinical situations where metal is present. Three clinical situations were evalu...

PURPOSE In computed tomography, metallic objects in the scanning field create the so-called metal artifacts in the reconstructed images. Interpolation-based methods for metal artifact reduction (MAR) replace the metal-corrupted projection data with surrogate data obtained from interpolation using the surrounding uncorrupted sinogram information. Prior-based MAR methods further improve interpola...

Filtration of a solution may lower metal concentrations through adsorption of metal species to the filter. Processes such as filter-sterilizing nutrient solution and filtration of field water are sensitive to these sorption artifacts, yet basic data on the affinity of different filters for metals are lacking. This article describes the adsorption of five metals to eight types of 0.2-microm memb...

In X-ray computed tomography (CT), the presence of metal objects in a patient's body produces streak artifacts in the reconstructed images. During the past decades, many different methods were proposed for the reduction or elimination of the streaking artifacts. When scanning a patient, the projection data affected by metal objects (missing projections) appear as regions with high intensities i...

OBJECTIVE Patients can experience urinary retention (UR) after Holmium laser enucleation of the prostate (HoLEP) that requires bladder distension during the procedure. The aim of this retrospective study is to identify factors affecting the UR after HoLEP. MATERIALS AND METHODS 336 patients, which underwent HoLEP for a symptomatic benign prostatic hyperplasia between July 2008 and March 2012,...

High-attenuation object-induced streaking and shadow artifacts in computerized tomography (CT) are somewhat connected to the misfit of the X-ray projection data to the range space of the Radon transform. This misfit is mainly due to the beam hardening factor of the projection data which is unavoidable for polychromatic sources. The major difficulty in dealing with the beam hardening-induced str...

OBJECTIVE Artifacts caused by metallic objects, such as dental crowns, dental implants and metallic orthodontic appliances, are a common problem in head and neck MRI. The aim of this retrospective study was to identify the main metal dental objects that produce artifacts on brain MRIs. STUDY DESIGN Imaged metallic artifacts and their sources were identified. Artifact image plane was rated on ...

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