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From the past 15 years, we are increasingly seeing use of flat

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panel devices in fluoroscopy.

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As you can see here, one of the major advantages of these flat panel

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devices, just at the outlook, it is a much

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smaller footprint compared to the image intensifier, which takes up a

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lot of space.

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So if we move into this position, the C-arm, I mean, whatever position, the

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space occupied is much less to the image receptor.

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And now an image of the digital detector or the flat panel

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detector does pretty much the same or even higher

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image quality level of work.

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This is a photograph of a modern fluoroscopy IR

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suite with a flat panel detector, and the operator is standing here

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with all these other buttons on the system operating to

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get a good image quality and so forth.

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So

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the fluoroscopy system, which is a flat panel detector, has an advantage.

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The smaller size allows more flexible movement during patient

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examination.

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It does not require a TV camera to produce electrical signal for

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display,

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and it produces direct electronic signal, as shown earlier.

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If the entire process is digital, hence reduced image

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noise caused by electronic component that dominates in the IR system.

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The direct electronic signal is proportional to the

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intensity of X-rays that impinge or hits

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on each detector element in a solid-state flat panel

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device. This is very important. How many of the X-rays

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are impacting on the detector element, which

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basically will produce the amount of-- Is proportional to the

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amount of the intensity of the X-rays.

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The flat panel device consists array of individual detector

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elements.

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They can be anywhere from 1.5 to 5 million

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individual detector elements.

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However, it also poses manufacturing challenges to make uniform

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array with few defective or degraded detect element.

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It's very important.

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As you can see here, on the top panel it show the II-based

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system, which occupies quite a footprint.

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Image receptor, intensifier,

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optical systems, video camera, and then it is

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distributed into TV system and everything.

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What I want to show you here is like,

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this is X-rays, 100% of the X-rays formation hitting the patient.

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Patient absorb, uncharted goes down to 82%.

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When it passing through the image intensifier, it goes down to

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50% efficiency and so forth.

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With the flat panel device, there is all these other things are eliminated.

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It directly converts the X-rays hitting the patient, interact

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with some scintillator to create electrical signal on a digital detector.

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This particular slide basically shows the different type of acquisition for

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an X-rays, both analog and

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digital.

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We hardly do analog system these days.

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Most of the system in the hospital are digital.

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And among the digital, there is both indirect and direct digital.

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For fluoroscopy, it is suffice to say right now, the way

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the images are acquired with the flat panel detector is what is

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called as an amorphous silicon detector with indirect

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capture.

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This is a side cut of a flat panel detector array design,

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which is each of these is called a detector element.

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And even though this may be one

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millimeter by one millimeter, part of it is also obscured by the

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electronic, which is running through the detector element.

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Therefore, the main component is much lesser here.

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And you go smaller and smaller, that's the challenge because how

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efficiently you can have the electronics smaller and smaller, and that's where

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the challenge is.

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So this particular system is called the detect

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element. The distance between the two systems are very important.

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And for a light conversion, typically, we use cesium iodide.

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As you can see here, when the X-rays hits the detector,

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if it is a cesium iodide crystal, the X-rays are

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converted to light, and they don't spread across the

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field. Rather, it goes unidirectionally to the

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X-ray detector.

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And it's shown here the magnified view of the cesium

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iodide spindle, which makes it efficient

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for all these amorphous silicon indirect capture digital

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fluoroscopy system.

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Shown here is a photograph of a typical monitor system

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at the control console or

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next to the table for the modern fluoroscopy system.

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As you can see here, it also shows the choice of the filter

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used, and it show continuously what frame

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rate you're operating and what is the tube voltage and tube current

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when we are operating on a fluoroscopy automatic mode.

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At the bottom is the buttons, which again tell what

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technique is happening, and it also allows system to do

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both magnification and non-magnification.

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This is a busy slide basically showing a one particular fluoroscopy

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system, flat panel system, which has a 20

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centimeter square space compared to the 10

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centimeter space size. And you can see here the

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different type of imaging modes available.

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This particular system can have eight different

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fluoroscopy mode, from all the way from 20 inch in rectangle

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all the way to 6 inch in rectangle.

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It has three input fields within the image

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system, which has the

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large 25 centimeter,

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medium 20 centimeter, and 15 centimeter

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in size.