Patient dose in radiography

What is exposure?

Number of ionizations created in air by radiation

What is Air Kerma?

Total energy of ionization events in the air

What is absorbed dose?

Measure the energy absorbed in the body per unit mass

What is equivalent dose?

Biological harm based on radiation type

What is effective dose?

Biological damage based on radiation and tissue types

What is the average dose for AP chest?

0.02 mSv

What is the average dose for AP Skull?

0.03 mSv

What is the average dose for AP Lumbar Spine

0.7

What is the average dose for Lumbar series

2.0

What is the average dose for AP Abdomen?

0.7

What is the average dose for AP Hand

0.001

What is the average dose for Dental Film

0.004

What is the average dose for dental fillm?

0.004

What is the average dose for IVP Series

2.5

What is the average dose for Barium Enema with fluroscopy?

7.0

What is the average dose for CT head

2

What is the average dose for CT chest

8

What is the average dose for CT Abdomen

10

What is the average dose for mammogram

0.13

What is the average dose for Coronary Angiogram

10

What is the average dose for coronary Angioplasty

30

What is the average dose for PET Scan (nuc med)

25

What is the average dose for MRI head?

0

What is the average dose for Ultrasound gallbladder

0

What is the average EfD from natural background sources averages about to what per year?

3 mSv

What is Background Equivalent Radiation Time (BERT)

Compares clinical doses and risks to those from natural background radiation

What is Entrance Skin Dose?

Common to describe patient dose, easily estimated by x-ray machine

What is the general fluoroscopy limited to a maximum ESE rate of what?

88 mGy/minute

What is the Entrance Skin dose formula?

ESD= mAs * Output exposure (mGy/mAs)

What is Dose Area Product?

takes into consideration the total area of tissue exposed

What is the formula for DAP?

Air Kerma in mGy * Field size in cm²

How can DAP be decreased?

Anything that decreases ESD or decreases field size

• Decrease mA, time, kVp

• Increase filtration, SSD (source to skin distance)

• Decrease field size

What is Fluoroscopy time?

most basic, least accurate method for tracking dose in fluoro proceduer

Increasing fluoro time does what to patient dose?

increase patient dose