Become your own DICOM Police.

Using "hot" tools such as DVTK makes you
look like these Italians using a Ferrari

One of the major challenges as a PACS administrator is the resolution of “finger-pointing” i.e. being able to locate exactly which device or software is “at fault” causing the problem at hand. Let’s look at a typical scenario. You arrive at your hospital in the morning to find the MRI images from the PACS are suddenly being displayed upside down, inverted, backward, missing certain key parameters, or whatever. Upon investigation you find that a remote upgrade of the MRI software was installed overnight, however, the MRI service engineer swears that the upgrade should not have any impact on the images displayed on the PACS, while the PACS vendor finger-points to the MRI vendor. So, you are stuck in the middle having to resolve the issue.

There are a couple of lessons learned:

-Always stay informed about any changes to your systems that are to take place. These can look very insignificant but anything that has to do with modalities, the RIS, network, and obviously the PACS itself can have unexpected impacts on your systems.

-Try to schedule mandatory changes in the middle of the week. Towards the end of the week, you’ll never be able to get the needed resources back into the office if there are issues.

-A good practice is to allocate one day every month for all routine updates, e.g. make the second Sunday of the month “change Sunday.” All resources are then scheduled to be available and time for testing the updates is allotted.

-Have a detailed policy for any updates that includes a checklist and sign-off, which require checking that images are properly displayed/handled and processed following changes made. A service engineer making any changes should not be allowed to leave the facility until the PACS SA has reviewed, tested and signed off on the changes made.

-No change should be allowed unless there is a rollback plan with the capability of reverting to the pre-change status, if needed, for whatever reason. In one of the facilities I worked with, the reason for the rollback was lack of training. The users demanded the software release be rolled back as no one was able to figure out how to use the new features.

Now back to locating the issue. There are a couple of tools that can assist you with identifying the issue. The first one we discussed earlier on this blog  with a corresponding video shows how to validate image headers. However, an image header could pass validation and still cause an issue. Another neat tool to assist you in determining what has changed after an update has been implemented is the so-called “compare” tool. This tool is also available as a free, open-source application as part of the DVTK toolkit family and allows you to set up a filter to ignore all the attributes that are different for each image (patient information, date, etc.) and will show exactly what has changed. A demo is available as well. (see link)

As I mention often in our DICOM training classes, there is no DICOM Police that you can call upon, and therefore you often have to be self-policing to locate issues and resolve finger-pointing between different vendors. Using the appropriate tools for header validation and comparing changes will go a long way to allowing you to do this.

PACS SA’s: The cream of the crop!

PACS Administrator Career series (Part 3): PACS SA career opportunities with imaging vendors.

The second interview which took place during our “hang-out” about the difference between careers at a vendor or provider side was with Daniel Knepper (see the video for the complete interview). Dan is another “ex” PACS administrator who has worked for a vendor in several different positions. Dan has also a mixed clinical, IT and sales background, having started as a X-ray technologist. (The information below is the “short” version as the full interview that can be seen on YouTube, see link).

As mentioned in an earlier blog, there are several types of vendor opportunities for PACS system administrators, Dan is a good example of someone who moved into both an application support and sales position at the vendor side.

Now the interview with Dan Knepper:

Herman O.: How did you get involved in PACS?

Dan K.: I started as an X-ray technologist and also got a BsC in business administration and marketing at that time. I did general radiology and CT for 4-5 years and tried to learn as much as I could. My first break into IT was when I got an opportunity to install RIS systems which was a good match as I got to know the radiology workflow. After 6 years I also got involved with PACS systems and moved to sales support and marketing.

Herman O.: Which position did you prefer? Sales/marketing or technical support?

Dan K.: I like sales a little bit better, especially the “thrill of getting the sale, which is similar when I was a PACS SA, i.e. having the thrill of installing a working system.

Herman O.: Than you took a job as a PACS SA?

Dan K.: Yes, I was getting a little bit burned out from travel and took a position in radiology informatics at a major teaching hospital taking care of radiology, cardiology and voice recognition. Having multiple hospitals to support, I had three people helping me. These professionals came out of radiology with a knack for IT, and we were reporting to IT with a dotted line back to radiology.

Herman O.: Now you are back at the vendor side?

Dan K.: Yes, after seven years with a provider, I switched again and now work with a contracting company.

Herman O.: Was it hard to switch back and forth?

Dan K.: There is definitely a cultural difference between providers and the corporate worlds, but you just have to be careful not to get into something that is over you had and that you clearly know the expectations that the employer has of you.

Herman O.: What do you see as pros and cons of working on either side?

Dan K.: At the vendor side, you’ll have to like to travel. Also, you will be involved with multiple projects and need to be able to juggle between them. It is also more challenging, in addition to the fact that there is a fine line between what was sold and can be delivered.

Herman O.: What is your recommendation for a PACS SA who is considering making a career change to a vendor?

Dan K.: Make sure you keep up with reading many publications, such as Auntminnie, Advanced Radiology, etc. You need to be forward thinking and know what the trends are in the marketplace. Going to conferences and following educational series is important such as at RSNA and SIIM.

Herman O.: What do you think will be the next development over the next 5-10 years we should anticipate as a PACS SA?

Dan K.: Lab, pharmacy and EMR system need implementation support which are not that much different. Try to volunteer for different projects as these are not that different. If you can speak, write and document processes well, it will really relatively easily be translate well your expertise to other subject matter areas. You can learn the differences in workflow, and there are subject matter experts in those department you can rely on.

Herman O.: Any final remarks?

Dan K.: Keep your resume up to date, list your accomplishments, and generalize them as they can be transferrable. In my opinion, PACS administrators are the cream of the crop as they are used to manage complex systems, and therefore their future should be bright!

How to use a QC test pattern to check monitor calibration

The AAPM TG-18 QC test pattern is
essential to check monitor calibration

Whether a monitor has good image quality often is expressed in subjective terms describing quality in vague and imprecise terms. Examples of these terms are “it looks too flat,” “the resolution does not appear to be up to par,” “the brightness is not sufficient,” “I am missing contrast,” etc. 

Quantifying image quality to take the subjectivity out of the equation can be done by using an appropriate test pattern. The reason I say “appropriate” is that many users still use the “old” SMPTE test pattern, or, they might use the advanced QC test pattern such as developed by the AAPM task force and don’t know how to use this pattern, or what to look for.

If used correctly, the AAPM TG-18 QC test pattern will indicate immediately if there are any potential issues with the calibration and/or monitor. Note that in addition to using the correct test pattern, it is also critical to use the test pattern that fits your screen resolution, as there are two different files, one for high-resolution monitors and one for physician workstations.

There are significant differences between medical-grade and commercial-grade monitors, more details can be found here, one of the main differences is that medical-grade monitors have automatic correction and calibration according to the DICOM standard requirements. For commercial grade monitors it is critical that the calibration be checked visually on a regular basis, which can be done with the AAPM QC-18 test pattern.

Many users only look at the two “blocks” in the test pattern showing the 5% and 95% contrast differences, representing 5 grey scale values, however, this is only a rough indication of whether the monitor is somewhat within range, but this is by no means sufficient for medical use. This can be illustrated by the fact that, for example, a nodule in a lung field might represent a difference of 3 grey scale values. If the monitor only resolves every 5 grey scale values, you would not see a difference between those three, and the lung nodule might go undetected. That is why this test pattern shows differences that increase or decrease one grayscale value at a time starting from the black or white region in the text displayed on the bottom labeled, “QUALITY CONTROL.” In addition, there are blocks in the test pattern that have either +/- 4 digital driving levels or roughly 8 JND's. embedded at the corners.
Sometimes a vendor device handles the images improperly by applying certain look-up tables and/or image processing calculations. This can be verified as well by inserting the test pattern into the DICOM format.

Images are available for download. A link, as well as a detailed demonstration of how to use test patterns, is shown here in this video.
Each medical monitor, and commercial grade monitors which are used for medical applications in particular, should have the AAPM QC-18 test pattern available. There are TIFF versions and DICOM versions allowing you to test the complete display processing pipeline. Some institutions bring up this test pattern daily as a QA check first thing in the morning. At a minimum, I would suggest that you have users check the characteristic features of the pattern at least weekly, and, obviously, if there is any suspicion at any time that there could be an image quality problem.

Storing documents in a PACS or RIS: bad idea.

Managing documents is not a new issue as document management systems have been in place long before and in parallel with PACS, department information systems such as RIS and LIS or CIS, or Electronic Health Record systems. However, while departmental systems were being installed, many departments have been scanning in documents into their respective systems to make them available to physicians.

With regard to documents, there are two categories, the first are medical record documentation which are essential for a physician to be able to do his or her clinical job, and the second are legal and regulatory documentation that are kept “just-in-case.” Examples of medical records include the sheet that conveys the clinical measurements done by a technologist when performing an ultrasound procedure, a requisition form that shows the reason for the study, or a diagnostic report from a previous study. The second category includes consents forms, HIPAA privacy release forms, and others. The staff members charged with scanning in these forms range from the “front-desk” medical receptionist to specialists such as medical records technologists. The latter are usually found in larger institutions that have a document scanner next to the CT or MR operator’s console.

How is this implemented? Let’s take radiology for example. For users who have PACS driven systems, these documents typically are encapsulated with a DICOM header and the capture station or software typically has access to the order so that the header can be populated with the same patient and study information. The formats are mostly the so-called “secondary capture” format, which can be thought of as a bitmap or screenshot. There is also an option to scan the document as a DICOM encapsulated PDF, which is used less, but has the advantage of being much more efficient, resulting in smaller file sizes. The disadvantage of the encapsulated PDF solution is that there could be PACS compatibility issues as not every workstation has the capability of viewing them. These PACS driven solutions make the documents available as part of the same study where the images reside, typically in a separate series and they are stored in the PACS archive.

For users who have departmental driven systems, where the worklist for the physician is created by a RIS or CIS, there is typically access to the department database and therefore the documents are scanned into the information system as files, which can be in JPEG, PDF or other formats such as TIFF. These are indexed and managed by the departmental information system database.

Dedicated document management systems do have their own databases and archives, and are often more sophisticated as they employ high speed scanners as well as sophisticated software performing Optical Character Recognition (OCR) to recognize patient demographics, which can be used to index the documents. Several institutions have worked on becoming totally “paperless,” and have established dedicated departments for scanning in all of patient documentation. See related blog on certification of document administrators on this topic.

The problem with all of these solutions is that they create “islands” of patient documentation and are application and/or department centric instead of patient centric. Two major developments, however, are driving a more patient centric approach. The first one is the meaningful use requirement for electronic health records implementation. The second development that has been going on in parallel with meaningful use is the trend towards a true enterprise or Vendor Neutral Archiving solution (VNA). A “true” VNA should provide storage, management and access to these documents.

So the best answer on where to store documents, i.e. either in the RIS, in other department systems or in the PACS is “neither one,” as these are both short-term, dead-end solutions. Rather, investigate how your electronic health record solution manages documentation and how your enterprise archiving system stores and retrieves them. That is the only way to provide a long-term, patient centric solution.