Meeting the challenge of continually growing imaging storage requirements

Andrew (A.J.) Braga

It is the nature of the PACS administrator job to be continually focused on storage. After all storage is part of the job title. Over the last decade, advances in imaging technology and storage solutions have put more pressure than ever before on PACS engineers and administrators to stay ahead of storage needs. To get the perspectives of working PACS administrators on the ongoing challenges of storage, PARCA eNews talked with Andrew (A.J.) Braga, PACS and Interfaces Manager and Alex Marmolejos, PACS Engineer at Southwest Diagnostic Imaging (SDI), a group of radiology practices covering the Scottsdale and Phoenix Arizona area.

SDI includes Valley Radiologist, Scottsdale Medical Imaging and East Valley Diagnostic Imaging. Together they operate 32 radiology clinics with a combined volume of 2.3 million images per year. At SDI Andrew Braga manages a team of six PACS professionals and 3 HL7 engineers serving 150 radiologists.

Alex Marmolejos

Q. Over your career how has medical imaging changed in ways that affect storage requirements?

A.J. : I will start with the implementation of using a Vendor Neutral Archive (VNA) in our environment. The VNA is used not only as a means of image storage, but used as a DICOM router and DICOM Tag modifier. Removing the local PACS storage and using a VNA means the use of Query Retrieval on a daily basis for prior comparisons and other image routing.


Q. How has the VNA impacted your jobs?
A.J.: The VNA has added more flexibility to our imaging environment. We are able to modify DICOM tags that previously were dictated on the scanner only. The flexibility of modifying HL7 messages within the VNA (MACH7) has proved to be quite valuable. Although, we have encountered a learning curve with the use of the VNA our experience in the job has benefited.

Q. Do all the radiologists at all three practice groups access the VNA?
A.J.: No. Currently EVDI (East Valley Diagnostic Imaging) has its own PACS and own local storage, so only Valley Radiologists and Scottsdale Medical Imaging (SMIL) radiologists are accessing the VNA.

Q. How have your storage requirements grown over the last several years?
A.J.: More of our sites are adding HD/3D Tomo mammography, which can range from 1 to 10 GB per study. We are currently adding Clinical Trials which result in us storing raw images for up to two years. Our infrastructure has been adding storage at the rate of over 140 TB a year and growing.

Q. What is your capacity?
AJ: We are currently at about 800 terabytes. In terms of redundancy we maintain a high level of availability with two separate data centers with database and image mirroring at both centers.

Q. So if one goes down you maintain immediate access?
Alex: Yes.

Q. How did you go about selecting the VNA system?
A.J.: Travis Haskins the former CIO led the search on which VNA to select. I know he appreciated the migration tools within MACH7 that were able to bring over our GE PACS and PHILIPS PACS data easily. The fetching engine was also a feature that was a plus and has allowed us to bring online all priors.

Q. Who is MACH 7?
A.J.: A company that is headquartered in Vermont and established in 2007. Their VNA was officially rolled out the following year. MACH7 has a product platform that includes a DICOM Viewer, VNA, Patient Portal, etc.

Q. What were the key features that SDI found attractive?
A.J.: 1. HL7 engine, 2. Migration Engine, 3. Prefetching Engine, 4. Price.

Q. What were some of the things the stakeholders were looking for?
A.J.: SDI is a radiologist-owned group so the stakeholders were a radiology committee that assisted on selection. They are mainly looking for a system that works and doesn’t cost a lot, but would also help with hanging protocols.

Q. Do you know how that process went?
A.J.: We had three vendor-finalist involved in a months-long comparison testing and interviews with our stakeholders from the different practice groups.

Q. What is the process of monitoring storage usage and growth and anticipating the need for more storage?
Alex: The way we set it up now, is we get notifications to tell us when we have something like three months of storage left, so we have time to prepare, to order equipment, plug it in and get it running before introducing it to the system.

Q. How to you manage aging, archiving and purging?
A.J.: It is different for different types of studies. On the VNA itself we recently had a PACS migration from GE to Intelerad in which we brought over every study performed within the last 15 years.

Q. What are the system monitoring capabilities?
A.J.: It has a decent level GUI that lets you see your failure rates, failure counts, what is not being retrieved or failing to move across (the network). Those are being monitored everyday by the PACS team, which is helpful.

Q. Are there any things you’d like to have improved?
A.J.: The biggest thing for me is that you can’t move a series. You have to move a full study. You can’t select a certain series from a study and move it to another point.

Q. You mentioned a patient portal and referring physician portal, does that mean your VNA feeds into the EHR?
AJ: MACH7 does provide both of those products, but we currently have not implemented them in our environment as of yet. Our VNA does have an inbound and outbound HL7 feed into our RIS.

Q. Overall are you happy?
A.J.: Yes. We still have optimizing to do with the setup and routing, but it has been an enhancement to our workflow and productivity. MACH 7 support has been great through the process.

Q. Any advice for other PACS administrators?
A.J.: If you are going to use a VNA environment, I would always advise using the VNA as the endpoint and have load balancing, and not use your VNA as a DICOM router.