Monday, December 31, 2012

Cone-beam CT’s, not just for Cone-heads.

Cone Heads was a major hit movie in 1993

Cone-beam CT (CBCT) is making silent inroads into several practices by replacing certain technologies and providing better functionality as well as opening up new applications. The initial application was for dentistry, but it has spread its wings beyond that application. This article explains the basics of CBCT and lists a couple of integration issues you might need to be aware of.

How does it work? Well, as it name already reveals, the system uses a cone or pyramid shaped X-ray beam. As the name implies, it uses a cone shaped X-ray beam that goes through the object to be imaged and hits a digital detector producing an image. Except for differences in beam geometry, it operates very much like a conventional CT scanner. In contrast, the conventional CT has a fan-beam that results in a thin axial slice while the cone beam CT creates a 3-D object.  A CBCT might produce several hundred views while rotating 360 degrees in a single scan which might take 10 to 30 seconds to acquire.

Typical dental conebeam system
Compared with conventional radiography, such as a panoramic X-ray, the resulting images have less distortion, and compared with a conventional CT scan, they have a much higher spatial resolution, i.e. less than .01 mm, which allows for much higher precision that is especially important when creating dental implants. This higher resolution is mainly due to the smaller Field of View (FOV), ranging from 5 cm to 15 cm. The contrast resolution however, is much worse than for a conventional CT, due to several factors but mostly because of the high impact of the scatter radiation. The scatter radiation is typically characterized by the scatter to primary radiation ratio, which is typically .15 for a conventional CT scanner, but can be as high as 2.09 for a CBCT scanner.

The dose for a CBCT scan could be 5 to 100 times higher than for a conventional panoramic X-ray, but is at least 5 to 100 times lower than a conventional CT scan. This wide range is due to a wide range of dose delivery based on the field of view, collimation, and design differences among manufacturers. The cost is also definitely higher than for a conventional X-ray unit, as these devices cost at least $100,000, which might be a little bit hard to justify for a regular dental practice, which in many cases is barely able to afford a digital system to replace conventional byte wings.

O-Arm: cone beam CT for spine imaging
However, many years ago people would not have imagined that CT would now be the standard of care. In many ER’s, trauma patients are by default getting a CT scan, especially when there is any suspicion of head trauma. This is despite its higher cost and much higher dose delivery compared with a conventional X-ray. The same could happen with dentistry, where the panoramic X-ray units might start to be replaced with these CBCT systems, which is a scary thought. The scary part is that dentists are not really trained (yet) to interpret these types of images and do not have experience with radiation safety measures for their patients and staff. This is especially true if these systems are installed in a non-dedicated room, but, rather in a hall way or closet.
Dentistry is not the only application for CBCT systems, the high precision and portability also allows for ENT specialists to better image the inner-ear with its intricate structures. There is a also a dedicated CBCT system which allows for spine imaging, especially for spine surgery applications, which is referred to commonly as a “O-arm,” in comparison with the popular C-arms. There is a CBCT developed for extremity imaging as well. The latter allows one to stand up and therefore to image joints while carrying its person’s weight.
Extremity Imaging

With regard to integration, all these systems have a DICOM output for storing the images in a PACS or enterprise imaging and information system, and a worklist allowing these procedures to be scheduled in an information system or CPOE (Computerized Physician Order Entry) system. Scheduling might be a little bit tricky as the scheduled procedures have to be mapped by the modality worklist provider or broker to a specific station AE title. The dose reporting for these systems also is lacking as most CT scanners are starting to create the so-called DICOM structured reports to register this information because there are still changes that have to be incorporated in the DICOM standard to facilitate this specific geometry for dose reporting.

In conclusion, there are a few challenges with regard to implementing and integrating these systems, and the standard still needs to catch up with regard to dose reporting, but there is no question that these devices are here to stay and will increasingly be implemented in your enterprise systems. Therefore, it is time for support professionals to get ready and learn as much as they can about this new technology and be prepared to implement them. I myself learned a lot about this technology from my fellow DICOM expert Dr. Allan Farman who co-authored an excellent tutorial about this technology (see link).

Thursday, December 13, 2012

The bottom ten things you did NOT miss at RSNA 2012.

If you missed RSNA this year, you definitely lucked out; see my write-up here (earlier blog) about my top ten items. However, there are also several things you might not be sorry that you missed, so, here is my bottom ten list.

Adding these to Meaningful Use?
1.       Ultimate recliners – I am not sure what RSNA is doing about the decline in attendance (it was close to 10 percent lower this year), but I suspect that they are testing the waters and strategically posting some booths that are totally unrelated to radiology such as recliners. It does fit within this year’s mantra, which is all about the patient, so in addition to having the latest and greatest 640-slice CT or PET/MR, a patient might be pulled into the imaging center by recliners in the waiting room. Who knows, maybe next year the Lakeside hall might be dedicated to office and waiting room furniture. I actually wouldn’t mind having more of these as this particular booth was always packed and I would never have a chance to relax myself.

Ernie and his partner
      2.       Ernie’s welding shop – I found Ernie and his partner in the back of the hall promoting their welding shop while showing off some great work. I bet he has his Harley Davidson parked just behind the booth, and I am sure he would be able to create a custom job for your bike as well. I was unaware of the need for custom welding in the healthcare imaging field, but I guess as increasingly the production of tables and other mechanical parts is shifted to China, there could be an increased need to repair those, hence the need for Ernie.

Let me dry-skin you
3.       The ultimate dry-skin remedy– If you are on a limited expense budget or per diem that does not take into account the ridiculous price of food in Chicago, you most likely found yourself standing in the icy wind waiting for the morning and evening hotel shuttle buses instead of using a taxi. This is definitely detrimental to your skin, especially if you are from the south. The solution was offered by friendly ladies who tried to get you to use their all-natural Hawaiian Aloe skin lotion. Go for the daily free samples that will save you the expense of having to buy a pot of their cream for the RSNA “special” price of only $40, cash or credit card.

Great view from the walkway
      4.       The indoor walk trail/circuit ­– Where else would you find a tradeshow that purposely divides the meeting rooms and vendor booths on two sides of a major highway requiring you to walk about half a mile every time you have to go from one to the other side. This is especially dangerous during the times that courses are starting. You might bump into a person from Great Britain or Japan who is still severely jet-lagged and walking on the left side of the corridor. Or even worse, you run into someone who is in a heated phone discussion or is texting while walking. I strongly recommend that the RSNA put signs or arrows next year to indicate where people are supposed to walk and to prohibit texting while walking.

No recliners, but it will do.
5.       The most comfortable couches – So you finally got a sandwich costing you and arm and a leg, and then you find out there is no place to sit. I have seen many of those semi-desperate people as they try to hold on to the coffee, sandwich and an RSNA shoulder bag, wandering around looking for a decent seat. Here is the secret. In the middle of aisle not too far from the entrance, there are several comfy seats just waiting for you to plop down. But wait… maybe this is not part of the RSNA, well, at least they get the prize for the most minimalistic, yet functional booth.

      6.       The Jaws-sequel – One thing you probably won’t miss is the party hopping between vendor receptions in the evenings. One suggestion for next year is that we have a hangout, meetup, or whatever the latest social media term is, to let people know where the best food, entertainment, and/or drinks are so we won’t waste time attending receptions that are poorly attended and/or cheaply catered. (My favorites are those that serve Belgian chocolate and Swiss cheese). After these busy evenings, I typically try to unwind a little in my hotel room while watching some old rerun on HBO, in this case the movie “Jaws.” So, when I turned around the corner of an aisle the next morning, while semi-sleep- walking, I saw this big gaping jaw, which caused a flashback to the jaws movie. It was actually the so-called O-Arm, a cone beam CT dedicated to visualizing the spine, but that is besides the point.

Hustling the streets
7.       The cab drivers – The bus transportation system works great, but sometimes, when carrying a lot of luggage, I am compelled to take a taxi instead, or if I just missed the bus and don’t want to wait another 20 minutes in the freezing cold. I think Chicago taxi drivers rate as the worst among metropolitan cities. You are lucky if the driver will put your bag into his trunk, the curbside is definitely off-limits for them. The credit card machines in the back work 50 percent of the time, and if they do, they are cumbersome and seem to operate randomly. One time the driver actually shouted at me that I must be stupid to not know how to use it. They never wear seat belts (isn’t that the law in Illinois?) A good reason for me to wear mine is that the drivers strictly comply with their minimum speed limit on the highway of 80 mph. Their accents have to be worse than my “Texan accent,” so they are hard to communicate with. And yes, they also have to speak constantly on the phone using their Bluetooth earpiece in some language that is either Russian or an Arabic dialect.

Where to eat?
      8.       Lunch at the Hyatt – You would think that the Hyatt, after so many years of RSNA, would have learned a bit from how we manage wait times and communicate that effectively to potential clients. For example, in the metroplex where I live, there are signs along the highway notifying you of the wait time for the next ER down the road. One of them was actually quite innovative, as it advertised that you’d be seen in 15 minutes or it would be free! Going back to the Hyatt, I actually gave up trying to have lunch there, as the last time I checked, the waiting time was one hour for the next table. RSNA is very much about networking and talking with potential clients, partners or other associates over lunch or breakfast. I suggest therefore that RSNA consider signs in each of the corridors listing the average wait times to have lunch (and coffee!) at the various locations.

Ice-skating below
9.       The jelly bean – If you missed the Chicago jelly bean, shame on you. That means that you have spent all your time in your hotel room, going to early morning lunch meetings at yet another hotel or the Hyatt, ran to meet someone for coffee just before the exhibitions opened, spent all day running back and forth between halls A, B and Lakeside while also trying to catch a few interesting presentations, jumped in a cab at night to go party hopping to network and then went back to bed after watching some old reruns on your TV. Chicago in November is at its prettiest, just before the icy wind and snow starts. Next time, make sure you take at least a few hours off to explore this great city.

Worth the wait?
      10.   The lines for Starbucks – I need my coffee fix in the morning and also preferably in the afternoon. However, it appears that they can’t bring in enough baristas to get the wait time to be somewhat reasonable. I think I only had coffee once, and that was because someone else had ordered me an extra cup. It would be great if we could text our orders in, prepay with paypal from our smart phone and simply pick up our order. Who knows, maybe I’ll live long enough to see this happen.

All kidding aside, this was my 29th year visiting RSNA, and I wouldn’t miss it for the world. I can deal with the cold and grumpy cab drivers because of the opportunity for meeting old and new acquaintances, and I kind of enjoy the “off-the-wall” booths. However, having a place that you can order a coffee in less than 5 minutes, and actually have a seat to enjoy it and talk with someone would be nice. Maybe next year’s mantra should not be “all about the patient” but “all about the customer.”

Thursday, December 6, 2012

IHE certification: overstepping its boundaries?

IHE USA and ICSA labs have announced a new certification program which, according to a recent press release, will start at the Jan 28 connectathon.

Monitors at work at the connectathon
There is no question that the IHE organization had a major impact on interoperability because of its definition of many profiles in multiple domains, and the development of tools, test transactions, images, and educational programs and seminars. This activity, especially the connectathons, have been a major benefit to the industry as a whole and ultimately resulted in more effective and efficient care. Its work has had a major support from the user community and the industry. 

However, the recent press release indicates a major departure and extension from its current activities.

As a reference, the IHE governance states the following activities:
1. Development activities: the work that leads to publication of the IHE Technical
Frameworks; international in scope; organized along clinical and operational domains. 
Typically within each Domain, a Planning Committee annually selects the use cases and a Technical Committee profiles the use of standards to address the use case, documenting them in Technical Framework documents and their supplements.  A Domain Coordination Committee ensures that consistent processes and technical directions are followed. 
2. Deployment activities: regional/national testing and demonstrations of the profiles contained in the Technical Frameworks and their supplements, as well as promotional and educational efforts. Testing activities include the development of testing software and related tools. Deployment activities are organized by National and Regional Deployment Committees that are separate entities with a close collaborative relationship with IHE International.

In my interpretation, certification is not currently defined in the governance and I would expect that this would require a change in the governance, and discussed with all stakeholders prior to taken this major change in direction. I am not a direct stakeholder, so I don’t know whether that has happened, but if so, I can’t understand how they would have agreed to this, especially because ICSA labs is a commercial entity (a division of Verizon).

Am I over-reacting, interpreting this incorrect or confused? Reactions are welcome.

Friday, November 30, 2012

RSNA 2012: It's all about the patient

There are two types of people who participate in the annual pilgrimage by visiting the RSNA trade show in Chicago:  the people who love it and thrive on the adrenaline and activities, and those who hate it. I belong to the first group, as it is exciting to see new products and gadgets, and to listen to the different languages around me while trying to figure their nationality. It is also a good venue to poll trends, get an idea of who is working where, and who moved, which new upstart companies are up and coming, who is acquired, and, last but not least, where is this industry going.

My perception was that there are still significant investments being made in healthcare, however, it is definitely shifting from buying devices and even PACS systems to building and expanding IT and infrastructure. For example, I heard many users complaining that “PACS systems have been commoditized” and vendors are not making any significant investments in this technology anymore. In addition, users have started weighing the benefits of buying yet another more powerful, bigger device, not only in terms of the bottom line, but also, and even more importantly, in terms of patient care.
Interestingly enough, the theme of this year’s event was all about the patient. 

However, as several speakers expressed, imaging, especially radiology, has been more removed than ever, not only from the patient, but also from the physician. One of the advantages of a PACS system that I heard often expressed is that the radiologist would not be “bothered” anymore by incoming calls, by technologists asking for advice or to consult, as images and results are readily available on-line. This had an unexpected negative effect of radiologists becoming isolated in a cubicle instead of talking with colleagues. This might not be a good development.

In a nutshell, what I learned is that healthcare imaging and IT are still good businesses, but the emphasis is shifting from imaging to IT. In addition, practitioners seem to forget the human interaction as it is easy to just stay behind your computer screen and hidden in your office. It is important to remember that emails and texting is no substitute for human interaction, which is still a critical part of healthcare.

Thursday, November 29, 2012

The OTech 2012 RSNA Awards.

The isles are always bustling with traffic

The 2012 RSNA in Chicago will most likely go into history as one of the lesser exciting and uneventful meetings compared with some previous years. Despite that, I was still able to find a couple of noticeable products worth sharing. Before you read the list I would like to add a disclaimer that this list is purely subjective and created with my engineering bias, so I tend to look more for new gadgets and exciting technology rather than clinical break-throughs. So, for any totally non-geeky persons, this list is probably boring, but for those who like new toys and gadgets, you’ll probably appreciate these.

Incredible engineering inside
1.       The Best Improvement Award goes to… the new 320-slice CT scanner. The Japanese might not be known for the most innovative and/or creative product designers and engineers, but they are masters in taking an existing concept and continuously improving, enhancing and refining it. This new Toshiba CT is a great example of that. It has a record scan time of about .25 seconds. Just imagine four rotations every time you say out loud “twenty-one, twenty-two, twenty-three, etc.” The G-forces on the X-ray generator, which is mounted on the gantry, must be enormous with that amount of weight and speed. The bore has been widened as well, so it is ideal for obese heart patients who need a cardiac scan, of which we regrettably have plenty in this day and age. No question that this is a major engineering accomplishment.

CCFL and LED next to each other,
no visible differences on the outside.
2.       The Ultimate Green Award goes to… the new series of LED displays. CCFL (Cold Cathode Fluorescent Lamp) technology is on its way out and being replaced by LED’s. For consumer lighting, this might still be a few years away as the price difference is still rather significant­­—imagine paying $20-$50 for a light bulb? For professional applications, however, such as display backlights, the advantages are significant. I would expect that in another year these CCFL based displays go the same way that old CRT’s went about 10 years ago. Every display vendor showed several samples of this new technology, but I found Eizo having the most complete LED based product line, with monitors of up to 8 MPixel using this technology. It is to be expected that the 10 MPixel displays, which are primarily used for digital mammography, will be available soon as well. Depending on the display type, the LED’s consume 50 percent to 30 percent less power. I noticed a significant difference in temperature just by touching the front screen indicating the energy efficiency. These LED’s are definitely more durable, and they don’t degrade as fast, therefore requiring less frequent calibration. The latter saves support and maintenance costs. Overall, a much better carbon footprint.

Definitely not a zero footprint
3.       The Most Over-hyped Award goes to…the “zero-footprint” viewers. Unlike the green technology, which is measured by carbon footprints, the “zero-footprint” concept refers to the fact that a viewing application can run on multiple platforms, including tablets and smart devices, without leaving a trace behind. There is no software to be downloaded and/or executed on the local client, which addresses the fear factor that most IT processionals have with potentially introducing malware and/or viruses. From a support perspective this is also highly preferred as a new release only needs to be installed on the server side. However, this concept is not new and merely a logical evolution to the browser-based web viewers. But because of a smart marketing ploy, suddenly every PACS vendor is hastening to announce that they too have released their zero-footprint viewer. Next year, this will be old news, similar to the VNA and cloud hype we saw in previous years. Oh well, we need a new marketing ploy every year to keep the users engaged and confused.

The control monitor on the bottom
manages the gestures while the top
shows the results of browsing
through a  series of slices
4.       The Innovation Award goes to…the mouse-less, gesture-based interface. One of the recurring themes in the RSNA informatics sessions is the lack of innovation in radiology and how we should take applications in the IT and consumer field to heart and apply them to this specialty. The gesture based interface showed as a commercial product for use in the OR by GestSure Technologies, as well as the poster in the informatics section using a similar technology in a research setting by a group of Swiss pathologists are prime examples.  A user can control a viewer application by simple left and right mouse controls being assigned to his or her left and right hands. I tried it and got the hang of it within a few minutes, while according to the manufacturer, it takes about 15 minutes to get trained and familiar with it. I am sure that it also depends on how familiar one is with this type of application, for example, I will bet that my 7-year-old grandson who beats me regularly in his WII games can pick this up in half the time and become more proficient than I ever will be. We need more of these kinds of toys.

Display shows an install
in Afghanistan
5.       The Most Ruggedized Award goes to… the vendor who deploys numerous Teleradiology systems in the areas where our soldiers are serving, such as Afghanistan and surrounding countries as well as previously in Iraq. I am talking about MedWeb, who has been able to provide systems that can reliably can transfer images from these areas of conflict to the medical centers in Europe for review and consults. With ruggedized implementation, I don’t only mean the hardware, but also the software, especially the communication protocols. The workflow also has to be foolproof, which is quite different than when using Teleradiology for emergency medicine in typical setting. The so-called workflow “exception cases” where patient information is unknown at the time of diagnosis are the rule instead of the norm in this environment.  The reason for the study or admitting diagnosis, which is typically part of the examination requisition, is frequently missing as well. Many PACS systems automatically create an exception or flag images as “unverified” or “broken” if information such as the Accession Number, or patient information is missing, again, this is the norm in this environment. I have a great deal of respect for these folks, especially their support people who install and maintain these systems on-site. There is a lot to be learned from these applications for use in a non-battle zone as well to make the product more robust and durable.

Pick your ambiance...
6.       The Ultimate Feng-Shui Award goes to … The vendor who does not only pay attention to product design but also includes its surroundings. Anyone who ever has had a CT or MR done, and while laying on his or her back, had to stare at a sterile ceiling with those blinding fluorescent lights knows what I am talking about. I am talking about Philips, who has been in the lighting industry since 1891 and is actually the world’s largest lighting producer as of today. Philips argues that it is not just about the light, but it is also, more importantly, about the ambiance. There have been studies done about the impact of lighting on productivity, and I can imagine that similar studies could be done about anxiety and potential stress levels that may be reduced by the proper ambiance. I can even imagine that more relaxed patients would cooperate more, listen to instructions by technologists better, and therefore have a positive impact on the workflow and efficiency. Now I am waiting for the vendor who could also take care of the typical “hospital” smell by providing an aromatic soothing environment as well.

Dental cone-beam CT
7.       The Most Disruptive Technology Award goes to…. Cone beam CT, which has evolved from dental only applications to spine imaging, extremity imaging, and for ENT applications as well. Because of its relatively small size, it is possible to image patients in a standing position as well, therefore imaging the impact of putting weight on certain joints. However for dental applications it seems to be the most disruptive as it could possibly replace the traditional Panorex devices in most offices with a full blown CT as this scanner has the capability to also take panoramic images in addition to the slice data which can be used for 3D imaging. The precision that can be achieved to create 3-D models is less than .01 mm, which is definitely much better than can be achieved with conventional CT imaging. Especially for dental implants, this increased accuracy is a major benefit, as they will create a much better fitting implant. The bad news is that this opens a whole new can of worms because those dentists now have to deal with these high tech, heavy-duty, dose-generating devices.

Additional spine stretching included
8.       The Best Pragmatic Product Award goes to... The company Dynawell, who came up with a very simple device which simulates the upright position while laying on your back using a set of adjustable straps and a scale. It couldn’t be any simpler, therefore you won’t need to invest in the new extremity CT or “stand-up” MRI and be able to achieve the same result. This simple solution is a good example of thinking outside the box and coming up with relatively simple solutions. We need more of these to lower the cost of these procedures.

Quite a large footprint
9.       The Most Promising Technology Award goes to… The many multi-modality devices which are becoming mainstream, such as the CT/PET, CT/SPECT and now also the CT/MRI. These modalities are not new by themselves, but the combination of these devices create a fixed reference point so that sophisticated mapping and fusion of these images, which would allow not only the anatomy but also function to be presented in a single view and is relatively simple to accomplish. It definitely greatly enhances the utility of the nuclear medicine images, which are traditionally very small, noisy and have a very poor resolution because of the limitations that a human body has with regard to dealing with radioactive tracers and agents. These systems are not inexpensive and especially the PET/MR requires a lot of square footage to operate, but for certain diagnoses, these examinations will very likely become the standard care. However, these devices will definitely not help in lowering the cost of healthcare.

A typical DR plate in its storage bin
10.   The Most Over-Priced Product Award goes to… Digital X-Ray Plates, aka DR. It took about 30 years for CR technology to become mature, commoditized and affordable. I worked on one of the first CR units made by FUJI in the 1980’s, which took a complete air-conditioned room to be installed and was in excess of $100k. Today, you can get a simple tabletop CR unit for about $15,000 to $20,000, which includes several plates, software, training, and warranty. Digital plate technology or DR, has matured with regard to its technology as the image quality is good, plates are now wireless and do not require a cable anymore, they are relatively robust and drop-safe and not as heavy as they used to be. However, they are still in excess of $50,000 for a plate. There are many small clinics around the world, especially in emerging countries that still use film in locations where even only $1.50 for a film is a major expense, if one can get film and chemicals to those locations to start with. This is in addition to the fact that two-thirds of the world population does not have access to basic radiology services, creating a need for an estimated 80,000 affordable X-ray units, for which digital technology could be a potential solution. The first manufacturer who is willing to price a plate based on the potential sales opportunity of tens of thousands of these plates will be able to create a true revolution in healthcare. As with many of these innovations, it might have to be someone from the outside, similar to what Apple did with the phones killing Nokia, or Canon with camera’s killing Kodak.

GE deserves a honorable mention for
their kid-friendly MRI
In conclusion, RSNA 2012 did not show a lot of revolutionary developments, but rather several significant improvements, and a couple of fun and small innovations. I am sure I missed some, don’t hesitate to point them out to me, or if you have any comments and/or opinions about these awards (even if you agree, I like to hear it!).

Monday, November 12, 2012

How to deal with finger-pointing between Imaging vendors.

As healthcare imaging and IT systems are getting more complex and the number of systems to be integrated is increasing, it gets harder to identify and troubleshoot interoperability issues. Information crosses several systems boundaries, several of which are not under the control of a healthcare imaging and IT professional, and almost always from different vendors. Upgrades and changes can occur at various systems and subsystems adversely impacting the operation. 

The key to resolving these issues is first of all locating the area of concern and then second visualizing it. This will assist the vendors who are involved to address the issue without them finger-pointing to each and not taking any immediate action.

An image might be incorrectly identified and/or processed wrong because of incorrect header information, which might have been initiated by an error in the personal Health Record (PHR), which was loaded into a Centralized Physician Ordering (CPOE) system, which placed an order through an interface engine, onto a RIS scheduler to a modality worklist broker, which was queried at a modality, copied the information in the image header, archived at the PACS, and retrieved at a viewer plug-in showing this information to a physician looking at an electronic health record of this patient.

To be able to address these kinds of issues, a Healthcare Imaging and IT professional needs to follow a systematic approach for locating the cause of the problem using a decision tree and then using the appropriate tools to visualize the issue. The good news is that vendors have stepped up over the past few years to increase their capability for logging, auditing and monitoring their interfaces, however, in many cases the errors are still vague and not to the point. Examples of such vague errors are “processing errors”, time-outs due to unidentified problems, resets or aborts, and many others.

In addition, there are also more tools available, most of them in the public domain that visualize issues at many levels of the interfaces, as detailed as the actual bits and bytes that are exchanged between the devices. The only barriers to using these tools is a general lack of knowledge and training of healthcare imaging and IT professionals as well as the vendor service personnel, and in some cases the lack of access to networks and routers due to security concerns by IT departments. The latter can in many cases be resolved by partnering with the people who are responsible for the IT infrastructure and try to get them involved with the resolution of the issue.

The first step in diagnosing the interoperability issue is to characterize and identify the type of issue. Tools to perform the diagnosis can be grouped as follows:
·         Utilities, such as accessible through a command line interface or service menu. These can be used to test basic connectivity for example by a ping or DICOM Echo.
·         Active simulators such as modality worklist simulators (see link for demo), RIS/PACS simulators, and viewers, all of them are available in the public domain.
·         Passive tools such as DICOM sniffers (see link for demo), also available for free which can not only make the information exchange visible but allows saving these interactions and have them processed by Validators to find out if there are any violations and/or issues with the data formats or protocol.
·         Validators to validate data formats (headers) as well as the protocol (see link for demo). Fortunately vendors who have developed an extensive set of validators also have made these libraries and utilities available in the public domain.
·         Test transactions in the form of scripts, and many test images to evaluate image quality as well as the image processing pipeline are available, mostly as a byproduct from the many IHE connectathons.

The interoperability issues that are to be identified using the tools above can be categorized into four areas:
·         Connectivity errors, which can be due to networking issues, incorrect addressing, problems with negotiating a connection between the applications, performance issues and status errors.
·         Display errors can be related to worklist issues for example, populating a worklist incorrectly. The correct display of the image and related information, hanging protocols, incorrect handling of Structured Reports, such as used to display measurements, CAD marks, identify Key images, or other information such as radiation dose. Overlays and presentations state information is a category by itself, including on how to handle incorrect “burned-in” text.
·         Image quality issues can be hard to identify as the source can be the image acquisition, modality processing, view station imaging pipeline or display itself. Test images and test objects inserted at various locations in the imaging chain will assist in troubleshooting these.
·         Exchange media problems are getting less but still present due to non-DICOM compliant CD’s being created that might have non-DICOM images, lacking a DICOMDIR, or stored in format not supported by the particular DICOM profile definition.

In conclusion, in order to troubleshoot interoperability issues, the first step is to follow a decision tree in identifying the type of problem, than selecting the appropriate tools to visualize it. Despite increasing complexity and many additional systems that are to be integrated, the availability of tools in the public domain, makes troubleshooting and diagnosing problems possible to be performed by Healthcare Imaging and IT professionals.

Monday, November 5, 2012

To upgrade or not to upgrade, that’s the question.

This would have been nice...

Upgrading when traveling sometimes poses the same dilemmas and choices as upgrading your software. Let me share with you my most recent travel upgrade experience, which was somewhat disappointing. Initially I was excited to get the email about my automatic upgrade to business class for my flight. As it was an early morning flight I was looking forward to a decent breakfast. However, at the gate, the agent told me that I owed them another $90 because I had run out of “stickers.” I reluctantly paid for my “automatic upgrade” as the flight was over 4 hours (which is my pain threshold for sitting in economy). Then, as I hungrily anticipated my breakfast, I was told they were out and that they only had cereal left as I was sitting in the last row. (Hint from a frequent flyer: Odd number American Airlines (AA) flights start serving breakfast in the back, even numbered ones in the front). Lastly, I took out my laptop only to find I could barely fit it in front of me as the person ahead had lowered his seat way back. So, lessons learned: I would have been better off keeping my exit row seat in economy, which would have been less expensive, and actually provided more legroom and workspace, something I’ll consider next time I’m offered an “automatic upgrade.”

Upgrading software can be a painful experience as well. I would classify these upgrades into the following categories: Operating System (OS) security upgrades, OS version upgrades, utility software upgrades and application software upgrades.

Security upgrades
These are a necessary evil. I say necessary because typically the longer you wait with these updates, the more vulnerable you are for a new virus or other malware product to hit your computer and potentially impact your system integrity. Although remote, there is the possibility that the upgrade will interfere with your other software, therefore, if it concerns a major upgrade, the vendor of your application software should typically test and release an upgrade for implementation. If the vendor takes too much time, you should do a risk analysis to assess the chance that you could be hit by a new threat, which depends on the firewalls and other measures you have in place to isolate your system, and weigh that against the risk that the upgrade by itself could impact system integrity. As a general rule, I suggest never allowing automatic updates, rather do updates manually after looking at the risk, and always test the upgrade first yourself.

OS version upgrades
This is a major issue, especially as we are about to go through this once again with Microsoft Windows 8. I would guess that the majority of institutions are still on XP, which, if you include Vista, is three versions behind Windows 7. Why change if something works? If there is no reason and/or need for additional functionality, I would stay with the old version as any new version requires training, testing, and impacts device integration as well. Some of the older peripherals might not even be able to work due to a lack of driver support by the vendors for new upgrades. Unfortunately, you might be forced to upgrade as the support for the old OS expires, but my suggestion is to postpone this type of upgrade as long as possible.

Utility software upgrades
Also a major issue, although most vendors have become smarter after being burned a few times. A notorious example of this used to occur every time a web browser such as Internet Explorer was upgraded, which would break web viewing software. Most software packages are starting to implement solutions that are as much as possible platform independent. Make sure to test any upgrades and again, postpone the change as long as possible unless you need specific new functionality.

Application software upgrades
Some new releases are known to have more bugs and/or be less reliable than their previous versions. A general rule of thumb is to stay away from any release that ends with a “0,” for example, but wait till the next level such as level “x.1” or even later, to make sure that all bugs have surfaced and changes been made and tested by someone other than yourself. If you use any “plug-ins” or other applications that are tightly connected, for example a special processing package, or a voice recognition application, make sure you are upgrading those at the same time, or verify compatibility as they need to be modified as well in many cases.

In conclusion, software upgrades in general are a necessary evil, and, as with upgrading during my travels, I would not automatically upgrade, but rather look at the alternative as you might be better off staying where you are. 

Wednesday, October 31, 2012

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.

Friday, October 26, 2012

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!

Tuesday, October 16, 2012

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.