Question

When you see that a patient has an “additive” pathology, what should you take into consideration when performing this exam?

Answer 1

Ans) Additive pathology:

- Increases the thickness, mass, density or atomic number of tissue and causes greater attenuation. This will require a higher technique.

- Theeffect of pathology on exposure is determined by whether the pathology is classified as additive or destructive Additive: aortic aneursysms, ascities, cirrhosis, atelectasis, CHS, Pleural effusion, pneumonia, empyema, hydrocephalus, pagets, hydopneumothorax, edema. Destructive: Bowel Obstruction, emphysema, pneumothorax, active TB, Osteoporosis, Gout, RA, Emaciated, atrophied or malnourished patients. AEC and digital systems-The same rules that apply for AEC and film screen systems apply for digital imaging.- AEC errors will not have an effect on the density since the computer will correct it.- However, errors that would normally create underexposure will still produce quantum mottle-Errors that would normally produce over exposure, reduce contrast scales and increase patient exposure.Each plus/minus 1 density is a change in 25-30 percent of the exposureErrors in digital imaging will not affect the density, it will affect the brightnessErrors have an effect on readout We do not do noise reduction Anatomically Programmed Radiography (APR)A 2ndform of AEC. -Uses preselected technical factors for each procedure-Technologist either touches an anatomy icon of written description of the part to be imaged-mAs determined by APR only based on average sized part. RT must increase or decrease mAs according to changes in size. -Some systems also require the tech to select the patient’s body habitus, or adjust the mAs accordingly AEC the only thing that you select is the kV and detectors. With APR you get a basic mAs for a body part .