HESI RAD V2 EXAM LATEST VERSION 100% CORRECT AND DETAILED ANSWERS AND QUESTIONS.

A step-up transformer with 300 turns in the primary coil is supplied with 220 volts to this primary. How many secondary turns are needed to produce a 66,000 volt output? - correct answer 90,000 turns What is the result if the total lead content of a grid is decreased? - correct answer Decreased scatter absorption. What is the purpose of shuttering? - correct answer To black out areas of light and make fine details more visible. In conventional tomography, the radiographer is able to control the thickness of the tomographic slice by altering which of the following? - correct answer Exposure angle. Which type of exposure technique chart would allow the radiographer to make small, fine adjustments for orthopedic work? - correct answer Variable kilovolts peak (kVp). An imaging department, having difficulty obtaining acceptable tangential patella images, has opted to have the post processing mode set to "fixed" for all patella images. Why is this a good choice? - correct answer Fixed mode works well for exams where it is difficult to center the image on the image receptor (IR). Pelvis routine calls for an anteroposterior (AP) with a perpendicular central ray (CR), and an axial AP with a 40 degree cephalic angle. Using a caliper measurement, the technique chart yields a perfect set of exposure factors for the perpendicular AP. How will the necessary exposure factors for the axial differ from the perpendicular AP? - correct answer Greater measurement, higher kilovolts peak (kVp) and milliampere-seconds (mAs). Which advantage does a 500 milliampere (mA) station have over a 200 mA station? - correct answer Increased photon flux to the image receptor (IR) A radiographer is performing a portable abdomen is using an image receptor with an 8:1 grid. The radiographer knows a technique for the abdomen using a 12:1 grid is 80 kilovolts peak (kVp) using 50 milliampere-seconds (mAs). Which would the new technique be in order to maintain image quality? - correct answer 80 kVp @ 40 mAs. If 7 milliampere-seconds (mAs) provides optimal density without a grid, which mAs should be used with a 12:1 grid? - correct answer 35 How does a radiographer maximize signal to digital image receptors? (Select the three that apply.) - correct answer Compression of the body part. Shorter source to image receptor distance (SID). Longer exposure time. What results from utilizing a lower ratio grid? - correct answer Lower contrast, but greater error margin in central ray (CR) placement. Why is it important for the radiographer to observe the milliampere seconds (mAs) readout at the end of each exposure when using automatic exposure control (AEC)? - correct answer This value may be used as a basis for calculating manual techniques. How does emphysema impact radiographic imaging of the chest? - correct answer Emphysema is a destructive disease, meaning the chest tissue is more radiolucent. If computed radiography (CR) imaging plates (IP) haven't been used, how often should they be erased? - correct answer 48 hours. In which way can the radiographer minimize motion due to peristalsis? - correct answer Decrease exposure time. Which best describes anode heel effect? - correct answer A phenomenon where x-ray intensity is greater under the cathode. Which will increase the appearance of noise in a digital image, assuming only the named factor in each response is changed? - correct answer Large matrix. Which is the preferred method for indicating the correct anatomic side on a radiographic image? - correct answer Place a side marker directly on the image receptor (IR) prior to exposure. If a radiographer wanted to double image density without doubling the patient's dose, which action should be taken? - correct answer Increase kilovolts peak (kVp) by 15% Which statement is correct regarding the relationship of patient dose to exposure index (EI)? - correct answer EI gives an approximation of the patient's dose. What is a method of electronic display resolution quality control testing? - correct answer Society of Motion Picture and Television Engineers (SMPTE) test pattern. A breathing technique is planned for a right anterior oblique (RAO) sternum radiograph. The intended exposure is 50 milliampere-seconds (mAs) at 75 kilovolts peak (kVp) at 100 centimeter source to image receptor distance (SID). Which milliampere (mA) station is preferred, assuming the radiographer ensures exposure occurs during the act of inspiration? - correct answer 50 How much compensation is needed for a change to a small focal spot? - correct answer None. If all the bucky digital images from one radiographic room seem to appear excessively noisy, what might the radiographer suspect? - correct answer The automatic exposure control (AEC) is set at an inappropriate speed class. How can the contrast scale be modified on a digital image? (Select the two that apply.) - correct answer Alter the window width. Collimate more closely Which computed radiography (CR) or digital radiography (DR) system produces images with the highest spatial resolution? - correct answer Amorphous selenium - direct capture DR. What could cause a computed radiography image with very noticeable lines uniformly in the same direction over the entire image? (Select the three that apply.) - correct answer Grid used with grid frequency equal to the image reader's laser scan lines. Noise resulting from the plate reader electronics. Grid utilized with grid lines running parallel to the laser scan lines of the image reader device. Which description best defines a histogram? - correct answer Graph where x-axis is the amount of exposure read, and the y-axis is the number of pixels. Which is one function of a picture archiving and communication system (PACS) network? - correct answer Downloading images from different imaging modalities. Determine the file size for an image with a 512 x 512 matrix and 12 gray scale bit depth. - correct answer 393,216 bytes. In order to increase the number of shades of gray displayed on a digital image what should be done? - correct answer Increase the window width. Which component of a diagnostic x-ray tube restricts the primary beam to the area of interest? - correct answer Collimator. Assuming other exposure factors remain the same, which source-to-image-receptor-distance (SID) causes the greatest reduction in x-ray quantity at the image receptor (IR)? - correct answer 72 inches. Which factor will increase x-ray beam quantity at the image receptor (IR) without increasing heat units produced by the tube? - correct answer Decreased filtration If a transformer has a greater number of turns in the secondary coil than in the primary coil, how will the output voltage be affected? - correct answer Increased. Which term refers to the process by which digital radiography (DR) systems adjust for exposure errors so that the image is displayed with proper brightness and contrast levels? - correct answer Automatic rescaling. Digital radiography has the ability to produce 16,000 shades of gray. What appropriate bit depth (dynamic range) does this represent? - correct answer 14 bit depth. Which function are Radiology information system (RIS) networks are capable of performing? - correct answer Tracking radiology scheduling information A finished radiograph has marked quantum mottle. Positioning, collimation, and identification markers are correct. Which action should the radiographer take? - correct answer Repeat the image with an appropriate increase in technical factors. Which material is used on most anode disks and is light, strong, and heat-resistant? - correct answer Molybdenum. Computed radiography (CR) imaging creates images with poorer resolution than that of film screen. What compensates for this loss of resolution? - correct answer The wide latitude. Historically, rhenium was alloyed to the tungsten in the filament of valve tubes to increase electron emission. What is the major reason this isn't used in x-ray tube filaments? - correct answer To permit fine control of electron emission by filament heating current. What would a continuous, fine, horizontal white line across the computed radiography image indicate? - correct answer Dirt on the light guide or laser head. Which pathologic condition will result in the greatest attenuation of the beam? - correct answer Ascites.