Beam Hardening Artifacts in CT (Single and Dual Energy)

Beam hardening artifacts in CT lead to darkening in the image such as cupping artifacts and dark streaks between highly attenuating objects such as bone or iodine.
The physics of beam hardening can be traced to the harder x-ray beams having effectively a lower x-ray attenuation, and longer path lengths create harder x-ray beams.
Water based pre-correction does a good job of correcting the cupping artifacts but dark streaks can remain between bone or iodine regions. So called higher order corrections for beam hardening help to significantly reduce the dark streaks.
Finally, dual energy CT and photo-counting CT offer a methods to inherently remove beam hardening artifacts through the acquisition where material specific information can be computed.

[@xeramainali9270]

Appreciating Explanation! Have gone through almost all of your videos and really like how you explain everything in understandable manner. Could you please do Lecture Series of MRI?

[@HowRadiologyWorks]

Thanks for leaving the comment Xera much appreciated. Once I work my way through X-ray and CT I will think about doing MR too.

[@abdovitamins6331]

Great explanation as always senior Brian. Can you please make a video regarding tube rating (X ray) in details?

[@HowRadiologyWorks]

You’re welcome Abdo vitamins. I’ll put tube rating on the list. Others drop a comment below if that interests you as well.

[@abdovitamins6331]

@@HowRadiologyWorks sure sir
We always enjoy your videos. You make physics sound easier.

[@menkiguo7805]

so helpful for my intro to medical imaging class final!!!!

[@HowRadiologyWorks]

Great, share with your classmates. Thanks for the note

[@PraveenKumar-ng1ss]

Sir i have one doubt please reply sir
Head ct scan has avg absorbed dose of 75 mgy. In this head ct is exposed to skin, bone marrow, salivary glands, thyroid etc which make around 60% and remaing 40% radiation is deposited in brain how true it is sir
Brain radiation is around 25 msv than 2 msv everyone report or 25 mgy
What is this concept sensitive organs concept
Absolutely all in a big dilemma
I did around 2-3 head ct scans without knowing radiation now iam convinced that it will kill me for sure

[@HowRadiologyWorks]

Thanks Praveen, sorry I can’t respond to individual dose questions.

[@user-et1rl8qv6n]

I am a radiology technician, and as for the dose of radiation that I was exposed to, if it was over different periods of time, this will not harm you at all because the effect of the radiation disappears from the body after a while, but if it was over close periods of time, it will definitely have a bad effect.