Healthcare IT: Monitoring the Modalities

 Originally published on July 31, 2019 by Shaun Behrens
Last updated on April 13, 2022 • 8 minute read

In an ongoing series of articles about monitoring healthcare IT, I've discussed monitoring the big picture, as well as monitoring the Picture Archiving and Communication System and the integration engine. Now, I want to cover the modalities. And monitoring these is not as simple as you would expect.

Firstly, what are the modalities? Here's an explanation from our Monitoring Healthcare IT Primer (available below):

Modalities refer to the devices and equipment used for creating medical images, such as Magnetic Resonance Imaging (MRI), X-rays, Computer Tomography Scans, and ultrasounds.

How Modalities Work, and the Challenges With Monitoring Them

Although there are several different types of modalities, the way that they fit into the healthcare IT infrastructure is similar. The modalities capture the medical images, and connect to a PACS to store the images there. The Digital Imaging and Communication in Medicine (DICOM) protocol is used for these actions.

Each modality also has a worklist associated with it. This worklist contains a list of jobs scheduled for the specific modality, as well as patient information. The biggest benefit of the worklist is that it prevents data errors that might occur if paper copies of the patient data were passed between the examining doctors and the personnel doing the imaging. With the worklist, you can schedule imaging appointments, pass the patient's data digitally to the radiologist, and then save that information to the PACS along with the images that are captured. 

There is a big challenge that medical IT professionals face with monitoring modalities: many of the imaging devices do not provide an easy way to monitor them. They traditionally do not offer SNMP or Netflow support, so bringing them into your monitoring concept is not possible in this way. Quite often, the devices do not even offer an API that you can use to extract monitoring data, and if they do, it cannot be integrated with an existing monitoring solution that might be in use.

So it is quite possible that in the hospital's IT infrastructure, the admins have a number of black boxes with no way of knowing what their status is. However, even if you cannot monitor the modalities directly, there is still a way to to bring them into your monitoring concept by leveraging the mechanism they use to communicate. That mechanism, as mentioned earlier, is DICOM. 

Monitoring Modalities Using DICOM

There are various ways to check up on the modalities, with just a little creativity (or the help of the right monitoring tool). Here are some ways of getting information about those black boxes in the medical infrastructure.

Check on availability and response times with C-ECHO

As it has been for many decades, a ping test is still the simplest and quickest way to see if a device is up and responding. While the traditional ping is not possible with many modalities, DICOM offers something very similar: the C-ECHO request. Like ping, you can send a C-ECHO request to a device and check that you get a response. You can (and certainly should) also check on how long it takes for the response to get back, because high response times might indicate problems with the modality. 

Count the worklist items with C-FIND

The number of worklist items currently associated with a modality is a good indicator of that modality's health. For example: if the modality has a bottleneck or malfunction, the number of items in the worklist might grow disproportionately. If the number of worklist items is too low, on the other hand, then it could be that requests are not being processed by the device. This count of the worklist items is a key metric to watch. 

You can use DICOM's C-FIND request to do a count of the worklist items associated with a specific modality, or check the count across several or all of the modalities. If you've established a "healthy" range for the count to be in, you can spot potential problems if the count goes higher or lower than the expected values. 

Check for images stored locally on the modality using C-FIND

The usual configuration for modalities is that they store the images they capture either to a PACS or to some kind of storage. If there's a connectivity problem and this is not possible (for instance, there is a network outage), the modality might be storing the images locally. Thus a good way to monitor for potential problems is to check if a modality has images stored locally. 

To do this, you can use C-FIND to check the device for locally-stored series or studies (series of medical images are grouped by study, so you can use either level to check for images). 

Monitoring Everything

It's possible to use the DICOM requests mentioned in this article to monitor the modalities, but ideally you need a solution that has pre-configured DICOM sensors. Our very own PRTG monitoring software has DICOM sensors available out-of-the-box (like the C-ECHO sensor, DICOM Bandwidth Sensor, and the DICOM Query/Retrieve Sensor), which you can then easily configure to monitor your modalities. Because PRTG also monitors the general infrastructure, you can then have everything in one place: your medical IT and your traditional IT.

To learn more about monitoring other aspects of healthcare IT, download our Healthcare Monitoring IT Primer below. And let us know in the comments if you have any questions.