AEC AUTOMATIC EXPOSURE CONTROL التحكم الاوتوماتيكي بعوامل الاشعة

AEC AUTOMATIC EXPOSURE CONTROL

#التحكم التلقائي في عوامل التعرض
#Automatic exposure control
#التحكم الاتوماتيكي بكمية الأشعة
#exposure factor
#kvp
#MAS
#X-Ray



What Is Automatic Exposure Control?

Any device that measures quantity of radiation either passing through Pt or image receptor -then

Automatically terminates exposure when predetermined optimal density is reached

You give up control of exposure density to a machine

Most technologists refer to AEC as "phototiming

Purpose of AEC

To deliver consistent, reproducible exposures across a wide range of:

• Anatomical thicknesses

Types of body parts and pts.

Equipment

• Techs

Rooms

DIFFERENT TYPES OF AEC

1. Phototiming: (no computer involved)

2. Programmed Exposure: (computer controlled)

3. Anatomically Programmed Radiography (APR) (similar to Programmed Exposure but with little pictures of anatomy)

All three of 3 types of AEC units use some type of radiation detector device

- Photodiodes (photocell)

lonization chamber

And a backup timer

Upside of using AEC

- Takes less time to set up technique -speeds up exan

- Improves exposure accuracy, as long as proper positioning is used

Lowers repeat rate

Saves pt exposure

- More consistency in density

from visit to visit

tech to tech

• room to room

hospital to hospital

Important to remember!

Never pucontrast filleanatomy oveAEC cell!

Or breast implant

Or metal prosthesis Or shielding

All rooms aren't calibrated the same

Rooms change over time

Service engineer calibrates initially using phantom then must periodically recheck