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So what are the main application of dual energy CT?

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Dual energy CTs, when it was introduced, are touted

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for a lot of revolution in the CT. But

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over the period of time, we have seen the key application or the

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niche application where it has established very well are the

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following. The most sought-after application is

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the gout detection,

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which has shown to be very effective with the dual energy

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CT. The other one is the application of metal

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artifact reduction. It also delineates the structure

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very clearly, so it is easy to differentiate the object,

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and it is also effective in diagnosis and follow-up of the

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treatment.

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Here is an example of the dual energy CT with the

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data sets obtained from dual source CT.

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So one of the disadvantage or the advantage,

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whichever way we want to look is, instead of obtaining one

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data set, now you can reconstruct into multiple data

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set of different energy range. So you have the raw

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data, which are of two different spectrum.

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Now we can obtain, I can reconstruct with both these spectrum images

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here,

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or you can actually mix and match the

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information and create what is called as a mono energetic

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X-ray,

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which is what ideally would be the most effective way, but now with the

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two spectrum, you can actually create a mono energetic image set.

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You can also create a blended set, a mixture of these things

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to create a blended set of 120 kV. You can also

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have a data set with a color-coded of the iodine,

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or iodine can be quantified. And then you can

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also have one of the other advantage of dual energy CT is

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like when you are doing a triphasic studies,

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you do three scans without contrast, with

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contrast arterial, and with contrast venous phase.

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Now, we can only get away by doing the arterial and

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venous phase and use those image set to call what is called

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as virtual unenhanced image after iodine

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subtraction. This can eliminate obtaining three

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scans to two scans, thereby reduce the radiation dose.

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That is one of the application.

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So here is one of the sought after application in the dual

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energy gout application. You can see here,

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the gout, the accumulation of calcification in

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the joints is not easily seen on a regular CT,

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whereas in a dual energy CT, you can differentiate the attenuation

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very clearly with a color coding. It's much easy to

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obtain an urate. You can see the urate crystals and

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calcium-containing mineralization very obvious with this

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gout application. That's where the gout application has been very well

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established with the use of dual energy CT.

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The other common application our clinician does is a

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bone removal application. With a switch of a button, you can

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actually subtract the muscles and only see the

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arteries and so forth. So basically, the accuracy of

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segmentation is very high, image processing very small.

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So here is an example of a CT angiography bone

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removal. So now this enables the radiologist to view very

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easily any occlusion or any other things in the whole

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artery running all the way to the down.

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And that's one of the application is pretty much heavily used.

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The other one is calcified plaque is visible in

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the MIPA after once you remove the bone.

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This is another application which is quite commonly done with

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using the dual energy CT, which was not possible with the

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regular single energy CT.