1. Identify the artifacts produced on the images during CT scans Essay

1. Identify the artifacts produced on the images during CT scans. Describe the - Essay Example measurements are consistent, so any error of measurement will usually reflect itself as an error in the reconstructed image (Barrett, and Keat, 2004, 1680). Artifacts have a major role to play in diagnostic accuracy because their presence can degrade the quality of image of computed tomography or CT scan. In this article, various types of CT artifacts and strategies to avoid or minimize them will be discussed. Based on their appearance, there are several categories of CT artifacts and they are shading artifacts, streak artifacts,ring artifacts (Goldman, 2007, 222), distortion (Barrett, and Keat, 2004, 1680), slab artifacts, step artifacts and blurring artifacts (Siemens, 2). Beam hardening effects is the most common shading artifact. they are due to imperfect correction of beam hardening and occur in almost all CT images. They appear as "nonuniformities in the CT numbers of a uniform material, such as CT numbers that are lower at the center of a uniform phantom than at the periphery" (Goldman, 2007, 222). The nonuniformities are most of the time less than 5HU and usually unapparent unless viewed through a narrow window. larger hardening occurs if the scan is passing through a contrast medium or thick bone regions. Shading artifacts can also occur due to scattering. But scattering is uncommon in recent scanners. Streak artifacts are very common and are encountered in almost all scanners. they occur mainly due to bad detector measurements or inconsistent measurements. Such inconsistencies occur due to metals, partial volume effects, motion, insufficient intensity of X-ray and malfunctioning of the tube arc (Goldman, 2007, 222). (Goldman, 2007, 222). Ring artifacts or partial ring or arc artifacts occur due to drift in calibration, errors, measurement inaccuracies and imbalances. The current generation CT scanners have corrective algorithms and are able to detect inaccuracies in measurements (Goldman, 2007, 222). Metallic artifacts

Critique of Anand Hollas Article Entitled Obsessed with Your Cell Essay

Critique of Anand Hollas Article Entitled Obsessed with Your Cell Phone - Essay Example The article is timely because the author was able to determine that our dependency towards technology particularly cellphone has already developed to a proportion that is already a disorder. The author intended to create awareness among the readers so that they would examine themselves if they are already addicted to their smartphones by comparing their behaviors to the behaviors cited in the article. And if they are, they can seek help just like what the subjects did in the article. The good thing about this article is that the author made its audience realize that addiction towards cellphone is not healthy. Many people especially teenagers think that their dependency towards their smartphones are cool when it is in fact not. It would be difficult to ascertain with certainty if the author had successfully convinced its audience that smartphone use has already assumed a proportion of disorder. There no surveys included in the article that provided reader response. But personally, I t hink the arguments of the author are quite persuasive. I may not be that totally sold with the point of view yet because I am still looking for more literature to support his claim, but the article has definitely made me think and consider that smartphone dependency of many people is already troublesome. If the study is to be believed smartphone addiction is already â€Å"similar to drugs or cigarette addiction† which is already troublesome. To say that I agree already with the author would be quite premature considering that there is only one point of view that is presented to me and does not have anything to support or refute his arguments. Basing however from experience and observation, I think that the author made a good case and if presented with supporting scientific literature that is peer-reviewed, his case could convince me. Inferring from my observation, I see a lot of young people who are hooked not just with their smartphones but also to social media such as Faceb ook and Twitter. Some are even exclaiming that they cannot live without their smartphones or their Facebook or they could not imagine life without it.