What's the deal with DICOM files?

[edwardcoast]

A neighbor of mine, knowing I work in software, asked me to print-out some images his doctor’s office took. He said the CD-R didn’t work in his Mac and if I could look at it. Sure, why not.

I tried it in my Mac and quickly realized this was a Windows thing only.

OK, I brought up the thing to view the images which I assume were from an MRI or CAT scan. Anyway, there was no way to simply print them.

He wasn’t looking for fine detail, just a big thumbnail of them printed for whatever purpose.

So I used SnagIt to do a screen capture which made PNGs out of them, and then I send them to the printer. There were only 4 images.

So what’s the deal with DICOM files? Why don’t they have way a built-in way to print? And more importantly, why don’t they have a way to export them as PNG or JPG files?

When I tried to open any of what I suspect were the graphic files on the CD-R on the Mac, it didn’t identify the files as graphic images.

Is there some logical reason why they make it difficult for them to be used in other graphic file formats?

[Pork_Rind]

I can’t really address your core questions here, but I’ll just point out that Photoshop opens and converts DICOM files just fine if you have that available. And if I recall correctly, there are free Mac compatible DICOM viewers out there. The last disc of X-rays I got had both PC and Mac app installers on it.

ETA: apparently the core differentiator for the DICOM format is that it is a container format for the relevant medical record info as well as the image file.

[Riemann]

The file format is not Windows-specific, although often the disc you get from a doctor will only have a Windows viewing app on it.
You can use the Horos app on either Mac or Windows, it’s free.
There’s also a free version of Osirix for either platform, but I think Horos is better.

[rat_avatar]

The problem is not with the file format but that you are using a consumer printer that lacked a DICOM grayscale standard display function (GSDF) profile.

The format was intentionally created in order to ensure that screens and printed images provide an accurate representation of the image. This is absolutely critical in a medical context but it requires on devices to have a known lookup curve that has been calibrated to the GSDF curve.

As this is not intended as a general purpose format targeted at the needs of consumers with non-calibrated printers, which may misrepresent the information in a way that could lead to serious health and safety concerns for a patient is not the primary use case. Those needs trump a consumer printer manufacturers failure to consider this use case and deliver a calibration curve. That is a a failure of your printer manufacture and is not a fault with the format.

Medical data needs to be accurate, and it is impossible to do this without calibrated devices.

[edwardcoast]

@rat_avatar

The problem is not with the file format but that you are using a consumer printer that lacked a DICOM grayscale standard display function (GSDF) profile.

The format was intentionally created in order to ensure that screens and printed images provide an accurate representation of the image. This is absolutely critical in a medical context but it requires on devices to have a known lookup curve that has been calibrated to the GSDF curve.

As this is not intended as a general purpose format targeted at the needs of consumers with non-calibrated printers, which may misrepresent the information in a way that could lead to serious health and safety concerns for a patient is not the primary use case. Those needs trump a consumer printer manufacturers failure to consider this use case and deliver a calibration curve. That is a a failure of your printer manufacture and is not a fault with the format.

Medical data needs to be accurate, and it is impossible to do this without calibrated devices.

This software had no print function to it. So that didn’t even check the possibly if I had the right printer connected to the network or not. Unless you are claiming the DICOM Windows viewer software sniffed the LAN to find a compatible printer and when it didn’t find it, removed it even as an option to print at all.

[edwardcoast]

@Riemann

The file format is not Windows-specific, although often the disc you get from a doctor will only have a Windows viewing app on it.
You can use the Horos app on either Mac or Windows, it’s free.
There’s also a free version of Osirix for either platform, but I think Horos is better.

Thanks, that’s very helpful. I didn’t know about the Horos application for the Mac. I will check it out.

[rat_avatar]

@edwardcoast

This software had no print function to it. So that didn’t even check the possibly if I had the right printer connected to the network or not. Unless you are claiming the DICOM Windows viewer software sniffed the LAN to find a compatible printer and when it didn’t find it, removed it even as an option to print at all.

I don’t know that exact product, but yes, it is (or more correctly was) part of the spec(or guidance) to actually not enable a print option if there wasn’t a calibrated printer available.

The idea is to avoid your health care provider from printing to an calibrated device, which may result in your doctor missing something like a tumor etc…

Accurate printing and even displaying information is a actually a non-trivial problem.

To be clear, this format is explicitly designed for medical imaging, and it is intended to protect both metadata and accuracy, the only reason it exists is to try and provide these abilities that were lacking in other formats.

[rat_avatar]

@rat_avatar

I don’t know that exact product, but yes, it is (or more correctly was) part of the spec(or guidance) to actually not enable a print option if there wasn’t a calibrated printer available.

The idea is to avoid your health care provider from printing to an calibrated device, which may result in your doctor missing something like a tumor etc…

Accurate printing and even displaying information is a actually a non-trivial problem.

To be clear, this format is explicitly designed for medical imaging, and it is intended to protect both metadata and accuracy, the only reason it exists is to try and provide these abilities that were lacking in other formats.

I missed the edit window but I intended the above to say " printing to an **non-**calibrated device"

[bob_2]

I am wondering why they need to be printed at all. Within my local hospital, an x-ray can be on the consultant’s screen seconds after the scan is completed. I don’t know what delay there is, but my GP will be able to get it on his screen by the time I get a follow-up appointment. Nobody prints them on paper at all - the resolution would not be good enough anyway surely.

[rbroome]

@rat_avatar

I don’t know that exact product, but yes, it is (or more correctly was) part of the spec(or guidance) to actually not enable a print option if there wasn’t a calibrated printer available.

The idea is to avoid your health care provider from printing to an calibrated device, which may result in your doctor missing something like a tumor etc…

Accurate printing and even displaying information is a actually a non-trivial problem.

To be clear, this format is explicitly designed for medical imaging, and it is intended to protect both metadata and accuracy, the only reason it exists is to try and provide these abilities that were lacking in other formats.

Interesting information. Thanks

[Bullitt]

@bob_2

I am wondering why they need to be printed at all. Within my local hospital, an x-ray can be on the consultant’s screen seconds after the scan is completed. I don’t know what delay there is, but my GP will be able to get it on his screen by the time I get a follow-up appointment. Nobody prints them on paper at all - the resolution would not be good enough anyway surely.

Doctors can be throwbacks. In my 20+ years working with EMRs and med devices, it has been like pulling nails getting docs to let go of their paper charts and go electronic. Less so now than 20 years ago, but I still see it.

There might be a printer(s) system out there that can print DICOM images to sufficient, diagnostic capability, but I’ve never seen one. The best way to view them is with an image viewer. Heck there are probably tablet-based DICOM image viewers available, so docs can view them out on the golf course and phone in his/her diagnostic decision.

gSearched: yep, there are. tablet-based DICOM image viewers - Google Search