Ch. 12 - Management of Patient Radiation Dose During Diagnostic X-Ray Procedures

How can effective communication help to reduce patient exposure?

alleviates uneasiness & increases likelihood for cooperation

How can immobilization help to reduce patient exposure?

reduces voluntary motion that would blur the image

What are the 2 types of motion?

voluntary, involuntary

What are 4 areas of the body that should be shielded whenever possible?

Lens of eye, Breasts, Thyroid gland, Gonads

When should gonadal shielding be used?

when gonads are within 5 cm of a properly collimated x-ray beam

What's a shadow shield

attached to x-ray tube & cast shadow over area wanting to shield

What is a quality control program?

Assesses quality of diagnostic quality images pertaining to repeats

Describe the air gap technique

Put space between patient and IR

When is the air gap technique used

In place of grids

Repeats resulting from what 2 factors must be eliminated on the part of the radiographer

Carelessness, poor judgement

__________ is used in radiation safety terminology to refer to the dose to the epidermis.

Entrance skin exposure (ESE)

__________ are the sensing devices most often used to determine skin dose directly.

Thermoluminescent dosimeters (TLDs)

Genetically significant dose (GSD)

average radiation dose to the reproductive organs of a population that could effect future generations

What is a bone marrow dose?

average radiation dose to active bone marrow

Why should fluoroscopically guided positioning not be a practice of radiographers?

unacceptible and unethical

What can the radiographer do to the technical factors to reduce motion for pediatric patients?

high mA & short time, Immobilization techniques/devices

Image Gently Campaign

gentle doses on CT scans for pediatrics

Image Wisely Campaign

necessary vs unnecessary exams

Radiographers must limit the patient's exposure by:

Using radiation reduction techniques and radiation protection devices

Consequence of blurry image

repeats

First step to reducing patient exposure

collimation

Female reproductive organs receive _____ times more exposure than male reproductive during pelvic radiography.

3x

In order for gonadal shielding to be effective, placement must be...

very precise

Types of shielding devices

Flat contact, Shadow, Shaped contact, Clear lead

Benefits of specific area shielding

Reduced exposure to area, Reduced number of x-ray induced genetic mutations

Combination of technical factors to reduce dose

high kvp/low mas

The amount of radiation a patient may receive can be indicated in 3 terms:

Entrance skin exposure, Bone marrow dose, Gonadal dose

Estimated GSD thought to be enough to alter genetics

0.2 mSv

Fluoroscopically Guided Positioning (FGP) is considered what type of practice?

unacceptable & unethical

Children are at a _____ times greater risk of cancer later in life if exposed to radiation at a young age.

3x

During a radiographic exam, what combination of technical factors reduce patient dose?

high kVp, low mAs

It is necessary to question a female patient of childbearing age regarding her:

1. date of last menstrual period

2. possibility of being pregnant

3. age of her first pregnancy

a) 1 only

b) 1 and 2 only

c) 1 and 3 only

d) 2 and 3 only

b

What is a frequent problem in diagnostic pediatric radiography and how do we overcome it?

Motion

Analysis of an image department's repeat rate:

1. provides valuable information for process improvement

2. helps minimize patient exposure

3. improves overall performance of the department

a) 1 and 2 only

b) 1 and 3 only

c) 2 and 3 only

d) 1, 2, and 3

d

Moving the image intensifier closer to the patient during fluoroscopy:

1. decreases patient dose

2. improves image quality

3. decreases the SID

a) 1 only

b) 1 and 2 only

c) 1 and 3 only

d) 1, 2, and 3

b

In digital radiography the number of different shades of gray that can be stored in memory and displayed on a computer monitor is termed ______.

grayscale