Show Xray film & film processing from Rakesh Ca QuestionAnswer Four steps to film processing Developing, fixing, washing, drying What is the sequence for processing a radiograph? Wetting, developing, stop bath, fixing, washing, drying What is the purpose of developing? To change silver ions of the exposed crystals into metallic silver. Name the two developing agents. Phenidone and Hydroquinone Which developing agent produces shades of gray rapidly? Phenidone Which developing agent produces black tones slowly? Hydroquinone What is another name for developing agent? Reducing agent Which developing agent controls the toe of the characteristic curve? Phenidone Which developing agent controls the shoulder of the characteristic curve? Hydroquinone What is the sensitivity center? A metallic conducting electrode through which electrons are transferred from the developing agent into the crystal. Name the buffering agent. Sodium carbonate Name the restrainer. Potassium bromide Name the preservative. Sodium sulfite Name a hardener. Glutaraldehyde Name the sequestering agent. Chelates What is the name of another restrainer? Potassium iodide What do restrainers do? Restrict the action of the developing agent to only those silver halide crystals that have been iradiated. What does a preservative do? Controls the oxidation of the developing agent by air. What does the hardener do? It controls the swelling and softening of the emulsion. What color does hydroquinone turn when it has been oxidized? Brownish A lack of restrainer could lead to? Development fog Chelates are also known as? Sequestering agents What does an activator do? Neutralizes the pH of the emulsion and stops developer action. What do fixing agents do? Remove unexposed and underdeveloped silver halide crystals from the emulsion. The temperature of the wash water should be maintained around _____ below the developer temperature. 3 degrees C/5 degrees F The dry-to-drop time for most automatic processors is ____. 90 seconds Developer temperature must be maintained around _____. 35 degrees C/95 degrees F) A grayish yellow or brown stain could indicate? Excessive fixation or use of exhausted fixer. Grayish-white scum could indicate? Incomplete washing Static marks are caused by? Static electricity due to friction between film and other objects. Developer temperatures should be checked how often? Daily The roller racks should be removed and cleaned how often? Weekly The proper developer action will only occur in an _____ solution. Alkaline The most common results of excessive developer temperature are: Decrease in contrast and increase in density A solution that is capable of giving up negative ions (electrons) is classified as a? Reducing agent Which developer chemical causes the film emulsion to swell? Sodium carbonate The solution that is maintained at the lowest temperature of approximately 90 degrees F is the: Wash During latent image formation, the concentration of metallic silver in the exposed crystal occurs in the region of the: Sensitivity speck One of the common causes of processor jam up is the depletion of the hardener in the developer solution called: Glutaraldehyde The solution that is maintained at the temperature of approximately 80 degrees F (27 degrees C) is the: Wash The termination of development process can be accomplished by placing the film in a/an: Acid solution The principal cause of oxidation in the developer solution of an automatic processor is the exposure to: Air Single-emulsion film must be loaded with the emulsion ________ the intensifying screen. Toward The emulsion is composed of gelatin in which photosensitive _______ ______ crystals are suspended. Silver halide The silver halides used in radiographic film are? Silver bromide, iodide, and chloride Small crystals = _________ resolution, ______ speed High, slow Large crystals = ________ resolution, ________ speed Low, fast _________ films are sensitive to all colors. Panchromatic __________ films are not sensitive to the red spectrum. Orthochromatic Large crystals + thick emulsion = _____ contrast __________latitude, and _________ resolution. Lower, wider, Less Fluoroscopic spot filming can be accomplished with _________ roll film or __________ film chips. 70mm roll film, 105 mm Film should be stored at a temperature of ______ or lower at all times. 20 degrees Celsius/68 degrees Fahrenheit Humidity of film must be maintained between ___ and ___ percent. 30, 60 _____________ is the only solution dramatically affected by contamination. Developer Contamination can occur if ________ drips into the developer tank. Fixer Film should be dried in a temperature range of ___ to ____. 120 - 150 degrees F Processed x-rays should be stored at about ______ and _____ humidity. 70 degrees F (23 degrees C), 60 The _________ __________ is designed to move a film through the developer. Transport system The _________ ________ moves film down in and up out of solution tanks. Transport rack The ________ ________ turns the film down into the next tank. Crossover network The _________ _________ turns rollers Drive system When damp film exits the processor, the cause is most likely to be the ________. Fixer _____________ is the measurement of the characteristic responses of film to exposure and processing. Sensitometry Either a _________ or a ____________ is required to produce a uniform range of densities on a film. Penetrometer, sensitometer A __________ is an instrument that provides a readout of the amount of blackening (density) on a film. Densitometer A __________ is a series of increasingly thick, uniform absorbers. Penetrometer A _________ is designed to expose a reproducible, uniform, optical step wedge onto a film. Sensitometer At 0.3 optical density, ________ percent of light is transmitted through film. 50 Increments of 0.3 changes in OD numbers represent a ___________ of opacity. Doubling ________ ____ _______ is the density at no exposure, or the density that is inherent in the film. Base plus fog Radiographic film density ranges around _____ to ___. 0.05 to 0.10 The range of diagnostic densities varies from ________ to _________. 0.25 - 0.50 Film resolution is determined by the ____ of the silver halide crystals. Size An _____________ relationship exists between film resolution and crystal size. Inverse Film speed and crystal size are _______ ______. Directly related Film speed and number of sensitivity specks are ________ ________. Directly related Film speed and thickness of emulsion layer are _______ ________. Directly related A change in density will affect contrast only when ______ or _________ the straight line portion of the D log E curve. Above, below The toe gradient is calculated between ____ and _____ OD 0.25, OD 1.00 Latitude and contrast are _________ related. Inversely High contrast = _____ latitude + _____ patient dose. Narrow, high Low contrast = ____ latitude + ______ patient dose. Wide, low Slow film = ________ patient dose. High Fast film = _________ patient dose Low Mismatching of film and screens often _________ patient dose. increases ______ sensitive film will not respond to most wavelengths emitted by rare-earth phosphors. Blue ______ is more sensitive to the entire range of phosphor emissions, including yellow-green wavelengths. Green The speed of an imaging system depends on the __________ of the layer of phosphor or silver halide. thickness Relative speed number are usually established at ____________ kVp, with ____ kVp preferred. 70 - 80, 80 Recorded detail, sharpness and resolution are measured as ____ ______ ________ line pairs per millimeter Define matrix. Square series of boxes that gives form to the image. Define pixels. The individual matrix boxes. Define voxel. A three-dimensional volume of tissue. Define noise. Random background information that is detected but does not contribute to image quality. Image noise has an _____ relationship to contrast. Inverse Window level controls _______ ________. Image density There is a(n) ______ relationship between window level and density. Direct Window width controls _______ _______. Image contrast There is a(n) _________ relationship between window width and contrast. Inverse Window width also controls _______ ___ _______. Visibility of detail Resolution is controlled by ______ ________. Matrix size Computed radiography is considered ________ digital. Indirect Direct digital radiography are _________ systems. Cassette-less ___________ include those that use photostimulable storage phosphor imaging plates, charged coupled devices and silicon. Indirect systems ________ _________ systems directly convert incoming x-ray photons to an electronic signal. Direct acquisition The most common phosphor with characteristics favorable for CR is ________ _____ ____ and ____________. Barium fluorohalide bromides, iodides The latent image is actually created by energy transfer during ____________ ________. Photoelectric interactions The smaller the pixel, the _______ the spatial resolution. Higher The range response of the imaging plate detector to x-ray is ________. Linear Images that are underexposed will show _______ ______________. Quantum mottle If scan frequency and grid frequency are similar and oriented in the same direction, a _______ _________ will be observed. Moire effect _________ ________ ________ acquisition systems directly convert incoming x-ray photons into electronic digital signal. Direct radiography systems Define CCD (Charge Coupled Device). A photodector that is capable of converting visible light into an electric charge and storing it in a sequential pattern. What is DICOM? System of computer software standards that permit a wide range of digital imaging programs to understand one another. Quantum mottle (orreticulation) is caused by ______ _______. Low mAs PACS integrates information from the ______ and ______. HIS, RISWhat is the chemical that prevents overdevelopment in the developer solution?Where developer is alkaline, fixer is acidic. Acetic acid is used to make sure that all development of silver crystals stops (otherwise, the gray areas of the film would continue to develop until they were black).
What chemical stops development of radiographic film during processing?One of the four basic ingredients of the developer solution; potassium bromide is used to prevent the development of unexposed silver halide crystals; also prevents film fogging.
Which chemical is used for film fixing process?Fixation is commonly achieved by treating the film or paper with a solution of thiosulfate salt. Popular salts are sodium thiosulfate—commonly called hypo—and ammonium thiosulfate—commonly used in modern rapid fixer formulae.
Which developer chemical causes the film emulsion to swell?Radiographic Film Processing. |
What chemical is found in an automatic film processor stops the action of the developer solution on film emulsion?
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