Film

Question 1

What type of film remains the least common radiographic image receptor used today?

Answer 1

Photosensitive film

Question 2

Manufacturing of radiographic film has to be very precise and high quality procedure in order to prevent what on the radiographic image?

Answer 2

Artifacts (unwanted objects on film)

Question 3

What are the 4 layers of the radiographic film construction?

Answer 3

1. Base
2. Adhesive Layer
3. Emulsion
4. Supercoat (overcoat - protective layer)

Question 4

• What does the base do?
• What is the base made out of (4)?

Answer 4

• The base provides a structure for the emulsion layer

Made out of:

• Glass (What Roentgen used)
• Cellulose Nitrate (very flammable and caused hospital fires)
• Cellulose Triacetate (non-flammable but expensive)
• Polyester (still used today)

Question 5

What must the foundation of the radiographic film be?

Answer 5

• Flexible
• Uniformly radiolucent
• Durable

Question 6

Film must retain its size and shape from…

Answer 6

• Radiation exposure
• Wet chemical processing

Question 7

Thickness of the foundation of the radiographic film ranges from ___ - ___ micrometers.

Answer 7

Thickness of the foundation of the radiographic film ranges from 150-200 micrometers.

Question 8

Why is the film base usually tinted?

What color is it tinted?

Answer 8

To reduce eye strain for the radiologist while reading the film

Tinted blue

Question 9

The film base is also covered with a special substance to prevent what?

What is this called?

Answer 9

Light from one screen crossing over to the other

“Crossover effect”

Question 10

The adhesive layer is a ___ coating of the “___” that is applied to the base to hold the ___ (active) layer on the base.

Answer 10

The adhesive layer is a thin coating of the “glue” that is applied to the base to hold the emulsion (active) layer on the base.

Question 11

The emulsion layer responds to what 2 things that strike it?

Answer 11

Light or radiation

Question 12

The emulsion layer is also called the “heart of the film”.

What are the 2 parts of the emulsion layer?

Answer 12

Gelatin and silver halide crystals

Question 13

What does gelatin do (in the emulsion layer)?

Answer 13

Supports the crystals and distributes crystals evenly on film

Question 14

What are silver halide crystals (emulsion layer)?

What is it made up of (%)?

Answer 14

Active ingredients of the emulsion layer

made up of:

• silver bromide - 95-98%
• silver iodine - less than 5%
• silver chloride

Question 15

What does it mean when a film is a double emulsion film or duplitized film?

Answer 15

Emulsion layer on both sides of the base

Question 16

What type of film gave the best detail?

What modems used it?

Answer 16

Single emulsion film

Mammography, CT, MRI

Question 17

Describe the dull and shiny side on a single emulsion film?

Answer 17

Dull = emulsion side

Shiny = base side

Question 18

What layer of the film is the protective layer/protects all the other layers in a wet or dry stage?

Answer 18

Supercoat

Question 19

What does the supercoat layer prevent during film processing or handling of the film?

What is added to prevent static artifacts on the film?

Answer 19

Prevents scratches and abrasions

Antistatic agent

Question 20

What are the 4 steps to manufacture the radiographic film?

Where must it take place?

Answer 20

1. Crystal Production
2. Ripening
3. Mixing
4. Coating

Must take place in total darkness

Question 21

Silver bromide crystals production is performed in total darkness.

What combination forms silver bromide crystals?

Answer 21

Silver nitrate and potassium bromide mixed with gelatin

Question 22

Crystal Classification and Shapes

Silver halide crystals are ___% silver bromide and ___% silver iodide

What are tabular shape used most commonly for?

What are the advantages of tabular shape (CAS)?

Answer 22

• Silver halide crystals are 98% silver bromide and 2% silver iodide
• General radiography

Advantages:

• Can use thinner emulsion (flat-triangular)
• Absorbs more photons
• Speed up processing

Question 23

Silver Halide Crystal Structure

• Resulting shape can be…
• However, the inner structure takes on a ___ form or cubic lattice
• Each ___ or ___ is a cubic lattice
• The lattice is strongly bound together by strong ___ bonds (Silver, ___, and ___)
• The cubic lattice allows for free silver ___ and free ___ to ___ through the lattice
• ___ is added to the lattice (forms the ___ speck in each cubic lattice)
• Acts as ___ to ___ the free silver ___

Answer 23

Silver Halide Crystal Structure

• Resulting shape can be many varying forms
• However, the inner structure takes on a cubic form or cubic lattice
• Each crystal or grain is a cubic lattice
• The lattice is strongly bound together by strong ionic bonds (Silver, bromine, and iodine)
• The cubic lattice allows for free silver atoms and free electrons to drift through the lattice
• Gold-silver sulfide is added to the lattice (forms the sensitivity speck in each cubic lattice)
• Acts as electrodes to attract the free silver ions

Question 24

When is the time where the silver halides are allowed to grow?

The size of the crystals determines their what?

Which crystals are more sensitive to light or radiation?

Which crystals are less sensitive to light or radiation?

Answer 24

• Ripening stage (silver halides allowed to grow)
• Photosensitivity (what size of crystals determine)
• Larger crystals more sensitive to light or radiation
• Smaller crystals are less sensitive to light or radiation

Question 25

_Mixing Stage_ Additives are added to the emulsion Spectual matching is ___ to match the ___ to the screen's visual color - "glow" given off by the \_\_\_. What do hardeners do? What stops the growth of organisms in the wet processor? What decreases the sensitivity to environmental factors (heat, cold)?

Answer 25

Spectual matching is **colored dyes** to match the **wavelenghts** to the screen's visual color - "glow" given off by the **intensifying screen**. * Hardeners **prevent physical damage** * **Bactericides and fungicides** stop growth of organisms in wet processor * **Antifogging agents** decrease sensitivity to environmental factors (heat, cold)

Question 26

What is the last stage of film manufacturing? What happens during this process? This process requires extreme precision. Then the film is ready to use!

Answer 26

* Coating stage * Emulsion layer applied/glued on the base

Question 27

_Formation of the latent image_ What happens when a light or radiation photon strikes a silver halide crystal? What is caught or attracted to the sensitivity speck? What will the electron (that has a negative charge) attract? A single photon may free thousands of electrons for what? What must be deposited for a black metallic silver crystal to be formed by chemical development of the latent image? The more black metallic silver crystal created at the sensitivity specks, the...

Answer 27

* Its energy removes an electron from the atom. * The free electron * The positive silver ions * Deposition at sensitivity specks * At least 3 silver atoms * The more black metallic silver crystal created at the sensitivity specks, the **darker the image**

Question 28

_Types of Film_ Direct exposure or nonscreen film: \_\_\_\_is used to expose the film. Used in ___ radiography, \_\_\_, and exams needing \_\_\_. Intensifying film or screen film: \_\_\_-\_\_\_% of the radiographic image is made with ___ given off by \_\_\_. * Can be purchased with a variety of \_\_\_, ___ ranges, film ___ and \_\_\_.

Answer 28

_Types of Film_ Direct exposure or nonscreen film: **ONLY RADIATION** is used to expose the film. Used in **dental** radiography, **hands**, and exams needing **best detail**. Intensifying film or screen film: **95**-**99**% of the radiographic image is made with **light** given off by **intensifying screens.** * Can be purchased with a variety of **speeds**, **contrast** ranges, film **latitude** and **resolutions**.

Question 29

_Special Application Film_ M D C L D F

Answer 29

_Special Application Film_ M**ammography** D**etail extremity radiography** C**RT imaging** L**aser** D**uplication** F**luoroscopic spot**

Question 30

_Film Speed: (Emulsion Layer and Size)_ \_\_\_ the emulsion layers, the MORE sensitive to light so ___ the speed of the film \_\_\_ the emulsion layers, LESS sensitive to light so ___ the speed of the film _Size of Crystals_ \_\_\_ the crystal size, the MORE sensitive to light so ___ the speed of the film \_\_\_ the crystal size, the LESS sensitive to light so __ the speed of the film _Resolution or Detail_ \_\_\_ the emulsion = less detail \_\_\_ the emulsion = better detail \_\_\_ the crystal size = less detail \_\_\_ the crystal size = better detail _Contrast and Film Latitude_ Larger crystal and thicker emulsion = ___ contrast film and ___ latitude Smaller crystal and thinner emulsion = ___ contrast film and ___ latitude

Answer 30

_Film Speed: (Emulsion Layer and Size)_ **Thicker** the emulsion layers, the MORE sensitive to light so **faster** the speed of the film **Thinner** the emulsion layers, LESS sensitive to light so **slower** the speed of the film _Size of Crystals_ **Larger** the crystal size, the MORE sensitive to light so **faster** the speed of the film **Smaller** the crystal size, the LESS sensitive to light so **slower** the speed of the film _Resolution or Detail_ **Thicker** the emulsion = less detail **Thinner** the emulsion = better detail **Larger** the crystal size = less detail **Smaller** the crystal size = better detail _Contrast and Film Latitude_ Larger crystal and thicker emulsion = **lower** contrast film and **wider** latitude Smaller crystal and thinner emulsion = **higher** contrast film and **narrow** latitude

Question 31

_Film Storage and Handling_ *Prior to exposure:* Should be stored \_\_\_ Age: See \_\_\_ Heat: Must be store below \_\_\_°F (\_\_\_°C) Humidity: \_\_\_-\_\_\_% Light: No light ___ in cassette Radiation: Protect film from \_\_\_ Exposed film is very ___ to even ___ exposures of radiation!

Answer 31

_Film Storage and Handling_ *Prior to exposure:* Should be stored **on end vertically** Age: See **expiration dates** Heat: Must be store below **68**°F (**20**°C) Humidity: **30**-**60**% Light: No light **leaks** in cassette Radiation: Protect film from **radiation exposure** Exposed film is very **sensitive** to even **small** exposures of radiation!

Question 32

_Film Identification_ *Each exposure must include* medical record information * ___ of exposure * ___ of patient * Name of \_\_\_ * Name of \_\_\_ * Patient ___ number * Type of \_\_\_

Answer 32

_Film Identification_ *Each exposure must include* medical record information * **Date** of exposure * **Name** of patient * Name of **institution** * Name of **ordering physician** * Patient **identification** number * Type of **exam**

Question 33

_Legal Medical Record = Patient Films_ It is the legal responsibility of the ___ to make sure the radiographic images are correctly marked!

Answer 33

_Legal Medical Record = Patient Films_ It is the legal responsibility of the **radiographers** to make sure the radiographic images are correctly marked!