Which of the following phases in the cycle of the cell word possess the highest radio sensitivity? D) M; in general, cells are most radiotherapist in M and most radio resistant in S phase. According to Bernie and Tradition, the radio sensitivity of cell is directly proportional to their reproductive activity and inversely proportional to their differentiation level. There for the pronounced radiation effect happens during the least maturity and specialization. Radar Pro-148) 5) Patient radiation dose reduction in computer radiography is limited by B) Image contrast; Contrast is defined as difference n adjacent densities in radiographic image, mainly used the details of the image visible. All image taken needs to be diagnostic, in-order to achieve that all images taken should be taken at appropriate technique. This limits our ability to reduce the patient dose by decreasing the technique used. If technique is reduced to lower patient dose the resulting undiagnosed image, in this case image need to be repeated and so increase patient dose. Bushing 168-170 and 566-573) 9) Radium watch dial painters of the sass’s and 1 ass’s were part of a group that developed a high rate of- cancer B) Bone; in the offs and 1930 uniformed women working in the watch dial painters ingested radium, which latter in their life resulted in some damage. Because radium is much alike with calcium most of it was deposited in bone, resulting in development of osteoporosis, Getronics sarcoma and many other carcinoma.
Though some women also was diagnosed head carcinoma and appraisal sinuses, bone cancer was the most common. (Radar Pro 186-187) 10) Filtration of the x-ray beam would have the least effect on; D) Exposure; the primary use of filtration is to remove selectively the low energy photons that can reach the IR. By removing this low energy photons (long wave length), filtration allows mostly only the short wave length x-ray photos to reach the IR. This reduce the scatter but increase the HAVE and beam quality.
Filtration do not affect the exposure rate. (Bushing 140-143) 14) the most effective type of gonad shielding for males for use during fluoroscopic procedures like an upper GIG exam would be A) Contoured contact; This are shaped or contoured contact shielding, containing 1 mm lead equivalent usually used to shield male reproductive organ. (Red-Pro 274 -276) 16) A lead apron with 0. Mm lead equivalent will attenuate about % of a kappa x ay beam.
C) 75%; lead apron are used as shield to reduce mainly occupational exposure. When lead apron is 0. Mm lead (Radar-Pro-331 -table 13-1) 21 At what level of radiation does the FDA recommend that a notation be placed in the patients record? A) 1 to gay (1 Otto radar); The FDA recommend notation should be placed in patient record when radiation is at level of 1 to gay . It is also recommended the area of the patient body that received the absorbed dose should also be noted. Radar Pro 259) 22) An individual receives 25 Mr. of exposure by standing 3 feet from a source of radiation for 2 minutes which of the following would be most effective in reducing exposure C) Standing 4 feet from source for 1 min; inverse square low states that intensity is inversely proportional to the square of the distance 12 = (25 x 9)/4= Mr./min (Bushing 139) 24) The is directly over the phosphor layer in an intensifying screen D) Protective layer; the layer of the intensifying screen that is closest to the radiographic film.
It is 10-mum applied to the face of the screen, and helps to the screen to be resistant to the abrasion and damage usually caused by handling. Provides surface for routine cleaning without disturbing the phosphorus layer and transparent to light. Bushing 216) 25) The conversion type of flat panel detector uses a two-step process. C) In-direct: Currently there are main types of flat-panel detectors used, direct and indirect. The main difference between the two types is the conversion process.
Indirect flat-panel detector A scintillation phosphor layer converts the energy Of X-ray photons to visible light photons The light photons are detected by the pixel photodiodes and stored in the form of electronic charges in the capacitors associated with each pixel Terms related to flat-panel detector Capture element ; in which the x-ray is captured ( In CRY the capture element is he photo-stimulator phosphorus ) Coupling element : is in which the x-ray generated signals is transferred to the collection element Collection element; can be photodiode, a charged coupled device (CDC), or thin film transistor (ET).
The first two are light sensitive that collects photons and ET is charge sensitive and collect electrons. (Bushing 295-297) 26) Anode angles usually range from to degrees B) 5-20; anode is the positive electrode in x ray tube which consists of target material made of tungsten alloy. Anode angle ranges from 5-20 (l found 7-20 in text book) which allows or greater focal spot, which produce smaller effective focal spot. When the target angel is greater, it increase the heat capacity. Bushing 1 15 and Mosses 40-41 ) 30) Interactions with the target include D) A&B; both breakthroughs and characteristic are the only interaction that happens at the target of the x-ray tube. Compton on the other hand is interaction that occurs when the x-ray photons reaches the patient, and so outside of the x-ray tube. (Bushing 129-132 and 149-150) 33 the x-ray capture element of a computer radiography imaging plate would be D) Barium fluoridated; The SSP storage plate within the IP have layer of europium-which is activated barium fluoridated.
This fluoridate serves as IP and stores the latent image. (Bushing 284) 42) Resultant effect of utilizing 100 speed screens, a . 6 mm focal spot and 100 mass C) Increase in recorded detail but no effect to density; as the focal spot goes to mm, recorded detail increase (smaller focal spot gives us better recorded detail). When it comes to density although mass is doubled from mamas to mammas (which is supposed to double density), the AS is also going down from 200 to 100 which is cutting density by half.
So then density is doubled by increase in mass but halved by crease in AS, which results no effect to density. (Bushing 211-213 and 388-391) 48) Which of the following would be the resultant effect of utilizing a combination off 25 SIDE and xx field size? D) Demonstration of anode heel effect; X-ray photons produced diverge more toward the cathode end but absorbed by the heel of the anode at the opposite end of the tube.