Help! Radiographs are grainy

RE: Help! Radiographs are grainy

Dave Chambers — Thu, 30 Jan 2020 05:54:56 GMT

This is excellent news, so glad that you have seen an immediate improvement in the quality of your radiographs.

The collimation issue could be controlled by a setting in the digital x-ray software. There is a possibility that the software does not have this feature, but I am sure your supplier can help with this

RE: Help! Radiographs are grainy

Lucy-lu — Wed, 29 Jan 2020 13:23:21 GMT

This information has been brilliant.We have done this today and what a difference already!

We still have a teething problem with collimation, as it still shows the whole plate even when we do, (but are due a service so will ask them to check this then).

Thank you for taking the time and all your advice.

RE: Help! Radiographs are grainy

Lucy-lu — Wed, 29 Jan 2020 13:17:58 GMT

Thank you for your advice.

RE: Help! Radiographs are grainy

Nick Shackleton — Tue, 28 Jan 2020 19:38:52 GMT

I don't have much else to add. I would say that some of the digital algorithms that are used to process your images can react badly if you have sandbags in the field of view and this will impact your image quality, so try to collimate down so these aren't included. also tighter collimation will help to improve your image quality

RE: Help! Radiographs are grainy

Dave Chambers — Tue, 28 Jan 2020 17:40:18 GMT

Hi Lucy-Lu,

On digital systems grainy images are caused when the radiation dose is too low, and the image processing algorithms do not have enough 'data' to process correctly. Think of it like a newspaper photo, rather than one in a glossy magazine.

In the majority of cases the problem is too little mAs, although sometimes the X-ray head (generator) can be the problem if it is an older low frequency unit.

I would start by increasing the mAs by around 50% to start with, and assess if there is an increase in image quality. You do need to be careful though of the exposure time, the 's' part of the mAs. Does your X-ray generator control panel show you the exposure time, or just an mAs figure?

If it is a low mA unit, then for thorax, and mid to larger dog abdomens you will need to increase the kV, so that the time is kept as low as possible, to avoid movement blur due to breathing motion.

I hope this starts you looking in the right direction, and you see an improvement. It is possible though that the digital processor, and software are old technology, and not matched to well to your generator.

I would need further information on the generator, and digital system to help any further

Kind regards

Dave Chambers DCR(R)

Radiographer