Applied Imaging: Current Trends in PACS

This is the third issue in a series of newletters that provides input from experts on the opportunities they have created by overcoming adversity in establishing successful PACS entities.

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EDITOR'S NOTE

This is the third issue in a series of newletters that provides input from experts on the opportunities they have created by overcoming adversity in establishing successful PACS entities. It has been a pleasure to provide this timely and meaningful material to you. If you have additional questions about PACS please do not hesitate to contact us for additional information.­­Ronald B. Schilling, PhD

Implementing Privacy and Security for PACS and Teleradiology: A Pragmatic Approach

Herman Oosterwijk, MS, MBA and Ana D. Cleveland, MS, PhD, AHIP

Providing privacy and security for picture archiving and communication systems (PACS) and teleradiology are complex issues that have been amplified by the Health Insurance Portability and Accountability Act of1996 (HIPAA). This article presents a pragmatic way to address these issues.

The HIPAA requirements, which are designed to protect the privacy and security of protected health information (PHI), are often misinterpreted. This sometimes causes delays in the implementation of new digital imaging projects. The distribution of medical images outside hospital boundaries, using PACS or teleradiology systems, is often affected. These misinterpretations are not caused by a lack of information, education, and/or resources; virtually every week a seminar or conference is available on this topic. However, most people address this issue from a purely information technology (IT) perspective and do not take into account the specific requirements of imaging. This misses the point of HIPAA, which is to protect patient privacy and information security without impeding patient care. The objective of the new regulations is definitely not to make it more difficult and harm patients. In emergency cases, immediate access to relevant patient information can be critical. The availability of patient medical history for a physician is equally important. The intention is not to lock up all information or overprotect it, even from a purely risk-management perspective. If an injured patient brings a suit against a facility, a jury would look more favorably on an institution that made an effort to make appropriate information available, rather than making it almost impossible to access relevant information.

On March 21, 2002, Tommy G. Thompson, Secretary of Health and Human Services (HHS), announced that the Bush Administration was proposing to "loosen" some requirements and simplify paperwork requirements. The changes include: removing mandatory privacy consent requirements for treatment, payment, and (healthcare) operations (TPO), while maintaining previous notice requirements; removing incidental disclosures from the minimum necessary requirement; eliminating the need for multiple research consent forms; giving an additional year for covered entities to negotiate new contracts with business associates; and simplifying the process for patient authorization for disclosure. As of August 14, 2002, the HHS has released final changes to the privacy regulations, adopting virtually all of these changes with only minor modifications. The compliance date for the Privacy part of the regulations goes into effect April 2003.

A key part of these changes addresses removing the need for a written patient consent to allow providers to use PHI for TPO. This would mean that sending an image electronically from a hospital to a doctor's home would NOT require patient consent. Not only would this requirement be in conflict with the TPO rule if an emergency patient needed an immediate consult, the lack of expedient advice from a physician would definitely impact patient care.

Deciding which technical means can be used to exchange images and related patient information confuses many people and stalls the initiation of new technology. We know of several cases in which a CIO, sometimes advised by a new security officer, has virtually banned any teleradiology connection by not allowing any external communications, for fear of security breaches. Direct phone lines and Internet connections have been particular targets of attention. One institution required that each connection have a $20,000 firewall and a secure network connection (at a monthly cost of several thousand dollars), which made a teleradiology connection impractical. Clearly, many direct phone or Internet connections are security threats. However, medical imaging vendors offer practical, cost-effective solutions using encryption and authentication that guarantee PHI privacy. Instead of blocking all external connections and/or forcing vendors into a cost-prohibitive scenario, IT departments should look at each solution on a case-by-case basis to develop affordable solutions to meet HIPAA requirements.

Trade-off between procedures, physical protections, and technical solutions are also misunderstood. For example, a viewing station might use sophisticated authentication and protection in the form of an access card, auto log-off when idle, audit trails of who accessed which information, etc. However, when this same device is used in a secured radiologist reading room that is only accessible by code by the radiology staff, these sophisticated technical means can be replaced by physical means. To determine when and where this trade-off makes sense, we developed a simple model dividing an institution in zones based on the impact on privacy and security (Figure 1).

Zone 1. The Radiology Restricted Access Zone includes all of the data, processing, and information storage within the radiology department, including portable modalities, CT, MRI, analog, digital, X-ray, etc. Information from digital modalities are sent to the PACS using the DICOM standard. Information can then be distributed to other areas of zone one from the PACS. People involved in the information flow in zone one are technologists, radiologists, and the file room and administrative support personnel.

Zone 2. The Radiology Extension Zone includes departments that need to access radiology information. Information is transferred between zone one and zone two via physical and electronic transfer methods.

Zone 3. The Hospital and Clinic Zone includes offices within the center where doctors might need to view radiology information, such as exam rooms, doctor's office, nurse's stations, light boxes, etc.

Zone 4. The "Network of Networks" Zone encompasses places outside the hospital that need to access radiology information. Information access can occur electronically, physically, or via telephone or fax.

For each zone, the trade-off must be made between procedural, physical, and technical means. For example, it would be overkill to send encrypted images electronically within zone one between a CT scanner and a viewing station. Within the restricted-access zone one, encryption would slow down communication unnecessarily. The network used is typically does not have any external access capabilities and protected by firewalls and network routers that do not allow any external traffic. However, if the CT is located in an outpatient clinic and the images are to be sent using a public network, encryption must be used. The same applies when retrieving an image from a PACS archive from a workstation within radiology; no extra technical means are required for the image communication itself. However, if the workstation is located in a physician's office in zone three or a home office in zone four and the information is sent via the Internet, the provision of a virtual private network or other encryption is certainly in order.

These trade-offs are not only for business reasons, implementing maximum security at every device would be expensive, especially when there are legacy devices involved that would require a major upgrade. The potential impact on patient care of making timely information unavailable is more important. Again, common sense and pragmatic solutions should prevail.

Some technology used for security is relatively inexpensive and/or freely available. Most recent operating systems can require a user name and password for access. Built-in utilities can encrypt certain folders on a computer. Virtually every financial transaction via the Internet is secured, part of which is a built-in component of standard Internet browsers. The same authentication and encryption can be used to exchange medical images. The DICOM standard has specified security profiles that allow a standard exchange of images and related information. The fourth year (2002/2003) of the Integrating the Healthcare Enterprise series of demonstrations organized by the RSNA and HIMSS will demonstrate some of these security features through connectivity among different vendors.

This article has focused on technology, rather than procedures. However, a good rule of achieving HIPAA compliance is to use 80% procedures and accompanying training, and 20% technology. Technology, such as access cards and/or password authorization is important, but even more important is eliminating "sticky" notes on monitors with user names and passwords. Institutions with many rotating residents will require someone to manage passwords and access privileges on an on-going basis. High protection on a workstation suddenly becomes irrelevant if it is positioned so anyone can look over a physician's shoulder and see images and related reports. Even if the monitors are screened from passers-by, open discussion of the patient between physicians, audible to anyone, also defeats the purpose. Without proper training and procedures in place, any HIPAA compliance will fail.

CONCLUSION

Make sure to use common sense when implementing HIPAA compliance solutions, and use widely available practical solutions. If in doubt, ask experts, from the department of HHS or others. Be aware of consultants that use "scare tactics." Instead, work with consultants that can interpret the requirements sensibly to provide pragmatic solutions. Do not "outsource" HIPAA compliance, but take responsibility and work with an internal team. Finally, do not lose track of the ultimate objective of providing high-quality care to patients using all relevant information to make informed healthcare decisions, while maintaining patient information privacy and security.

PRACTICAL ISSUES

Fundamentals of the
Electronic Medical Archive

Edward M. Smith, ScD, FACNP

When PACS was first introduced, it was considered a radiology resource to store radiology studies in DICOM Part 10 format and distribute them to the radiologist. Today, PACS is a part of the healthcare enterprise (HE) that is used to store and distribute studies of all types: images, waveforms (eg, electrocardiograms), and structured reports to all healthcare professionals in the HE and beyond.

The electronic medical archive of the PACS and the infrastructure are the two most critical components of PACS. The archive consists of two components: the archive manager (AM) or equivalent (the control center), and the associated image storage system and related storage management software.

The AM is responsible for the acquisition, storage, distribution, retrieval, and display of studies acquired from the various modalities, stored in the archive, displayed on various types of workstations, and printed to various hardcopy devices. The hardware and software of the AM must be available at least 99.99% of the time.

The network infrastructure or local area network (LAN) must have at a minimum 1 Gbps backbone and 100 Mbps switched to the desktop for diagnostic and clinical review workstations and be available at a minimum 99.99% of the time. The storage system must be able to write images to the storage media and retrieve and send images to the various workstations rapidly under AM control. The storage management software must be able to replicate the various databases­­demographic, image, and hierarchical storage management (HSM)­­both locally and remotely for disaster recovery. Typically, the demographic and HSM databases are stored on redundant array of inexpensive disks (RAID) in level 1 and the image database is stored in RAID level 5. These data are duplicated in RAID level 1 and in RAID level 5, if a disk becomes corrupted, the data on the disk can be reconstructed on the "hot" spare.

The AM, modalities, and the radiology information system (RIS) must communicate seamlessly with each other. This communication was initially accomplished using a uni-directional connection from the RIS to the modalities and PACS via a PACS Broker. The functionality of the PACS Broker is to translate Health Level 7 (HL7) messages into DICOM and vice versa. HL7 is a messaging standard that is used by the RIS and many other databases in the healthcare industry to communicate with each other. Today, several RIS and PACS vendors are working together to provide seamless bi-directional integration of the RIS with the modalities and PACS to take advantage of DICOM modality worklist (MWL), DICOM modality performed procedure step (MPPS), and the integration profiles developed by the IHE consortium. These steps will improve patient care, increase productivity, reduce errors, and reduce cost.

ARCHIVE MANAGER REQUIREMENTS

The archive and AM must have the following attributes:

* Connectivity, interoperability, and DICOM functionality with all of the other PACS components, the modalities, and other related devices, such as printers;

* Seamless integration with the RIS;

* Virtual image database with global query and retrieve (so patient data or studiesy can be retrieved from any workstation without prior knowledge of where the study is stored);

* The workflow defined by the AM must be programmable to meet the changing needs of the HE;

* A scalable storage system that can store a few TB to tens of TB and associated storage management software that is independent of the number of studies performed and stored both on- and offline. The storage system must be media independent, ie, must be able to support hard-disk, magneto-optical disk, DVD, tape, or any media developed in the future;

* Administrative functionality (monitor system resources, provide flexible audit trails that can be displayed and printed out, and offer proactive system monitoring, including e-mailing and paging, etc.);

* Data migration from one medium to another when the media or read/write mechanisms are no longer supported or available;

* Redundancy and 99.99% availability with a maximum downtime of ¾15 minutes for any single outage; and

* The ability to provide a copy of all databases that can be automatically or manually securely stored remotely.

The AM manages the distribution of studies, the PACS databases, and storage of studies. Studies are distributed throughout the HE using the rules-based or on-demand paradigm. In the rules-based approach, the current study and related prior studies are fetched to study server (SS) and/or workstations (WS) on which the study is to be read by the AM. The current and prior studies are stored on the SS and/or WS. In the on-demand paradigm, studies are not stored on the SS or WS but are retrieved from online storage by the user when they are to be interpreted. Typically, the first image of a study should be available for viewing within 3 seconds after it is queried by the user. The WS used for the rules-based approach is a thick-client, whereas the WS used in the on-demand paradigm is typically a thin-client. The on-demand approach is the method currently used by most vendors .

The AM manages the demographic, image, and HSM databases. The demographic database is used to store the DICOM header and facilitates the retrieval of studies. The image database stores the pixel data, the image, and portions of the DICOM header. Each entry in the demographic database is typically ¾10 KB while the studies in the image database range from a few MB to >500 MB. A single direct radiography or mammography image can contain up to 18 MB. It should be noted that studies are stored as one image per file except images of a multiframe studies, which are stored in a single file.

If the PACS utilizes an HSM database, this may be managed by the AM or by the vendor that supplies the storage system for the archive. The HSM keeps track of where images are stored and is used to organize, migrate, retrieve, and delete studies. The HSM in most PACS manages the storage of the images, however, in some current PACS a storage vendor, rather than the PACS vendor, provides the storage system, including the storage management software.

STORAGE REQUIREMENTS

The archive can store various types of studies from many modalities in different departments in the HE. The studies generated by these modalities require varying amounts of storage per study (Table 1). Storage requirements per study are steadily increasing. For example, multislice CT studies may contain >=300 images per study, while a single-slice CT typically contains 60 images, which is a 500% increase in storage requirement. A conventional MR acquires images in a 256 ¥ 256 image matrix, while a 3-Telsa MR can acquire images in a 512 ¥ 512 image matrix, which is a 400% increase in storage requirement. It is impossible to project future storage needs, because imaging technology is constantly improving and providing more data per study. The only certain thing is that storage requirements will increase with time for most modalities. This is why the archive must be scalable both with respect to the number of procedures performed and the storage requirement per study.

Studies are stored at the modality, WS, and hard drives for online (rapid retrieval) that is used to store from 30 days to 6 to 12 months of studies, plus prior studies if a rules-based study distribution paradigm is used. Some systems use a mid-term storage device, however, this is being phased out. Long-term storage typically uses a jukebox containing some type of tape media. Currently, some implementations deploy an all-spinning media solution that provides >=7 years worth of storage. In addition, some form of off-site storage is required for disaster recovery, which may be shelf storage (offline) or an off-site online storage system.

The types of storage media range from hard drives in a mirrored configuration RAID level 1 or RAID 5, which is a fault-tolerant array that can repair itself should one of the disks fail. The disks may contain from 36 to nearly 400 GB each. Other media include magnetic optical disks (MOD), various types of magnetic tape, CD, DVD, or the next new media. Only 12 to 24 months worth of permanent storage should be purchased when acquiring the PACS, since the cost per byte of storage is decreasing and the capacity per media is increasing with time. However, the long-term storage device must be capable of holding media to store >=7 years of studies and take into account the expanding storage requirements of the modalities and the HE.

DATA COMPRESSION

Data may be compressed to reduce the storage requirements and to speed the transmission of data between the modalities and various PACS components and between PACS components. There are various levels and types of compression:

* Uncompressed

* Lossless (which is a non-destructive compression method whereby the data can be reconstructed bit for bit). The compression ratio will vary from 1.8 to 2.8 depending on modality and body part.

* Lossy. With this compression, there is no loss of clinically significant data, however, the compression is destructive and cannot be reconstructed bit for bit. The compression ratios vary from 5:1 to >=30:1 depending on modality and body part. The use of lossy compression must be weighed in light of medical-legal implications.

When a vendor specifies the storage capacity for any component of PACS, it is incumbent on the user to make sure the vendor states the uncompressed storage capacity.

DISASTER RECOVERY AND HIPAA

The HIPAA mandates that an exact copy of all patient data be securely stored off-site in a recoverable manner. If the original copy of the data were destroyed or corrupted, the patient data must be able to be restored. This can be accomplished by simply having copies of all data labeled and securely stored off-site on a shelf in a vault (disaster recovery - restoration of service) to having a redundant data center miles from the primary data center that can continue operations within seconds or minutes if the primary data center becomes unavailable (disaster recovery - continuation of business). These are the two extremes of disaster recovery.

HIPAA also requires that each institution have a disaster recovery plan. This plan must include identified personnel to carry out the plan, a written procedure manual, and documentation that the plan is practiced at least annually.

FUTURE OF THE ELECTRONIC MEDICAL ARCHIVE

Only a filmless HE will result in a productive and successful PACS, not just a filmless radiology department, The objective must be "Images Anywhere at Anytime." The archive will be an HE resource to store DICOM objects, wave forms, and structured reports from multiple departments. Web technology will become the primary technology used to distribute studies for diagnostic, clinical, physician review, and teleradiology purposes. The archive will reside in a sophisticated primary data center. Enterprise storage will be used and all studies will reside on hard disk or the equivalent. Disaster recovery will be mandatory and recovery solutions will migrate to the "continuation-of-business" model for large enterprise implementations. PACS will not exist in its present form, but there will be an integrated HIS/RIS/PACS solution. n

ECONOMIC ISSUES

Impact of PACS on the radiology system

Ronald B. Schilling, PhD and Edward V. Staab, MD

The world of radiology has become a complex service and business. Radiologists provide diagnostic information by analyzing the results of studies obtained from sophisticated imaging equipment, and are increasingly performing a myriad of new treatment options. A growing number of professionals and skilled experts support the radiologist in this endeavor.

In today's large imaging centers, the "team" mentality includes physicians, technologists, nurses, administrators, secretaries, and file room and billing office staff. Engineers, informatics staff, physicists, and maintenance personnel also may be part of the inhouse team. In other situations, some of these tasks are outsourced to contracting firms. The advent of conversion to PACS-based departments is affecting how each of these individuals are called on to provide expertise to assure a successful radiology service.

Fundamental to the service of radiology is the diagnostic image. Whether the image is used for diagnosis of a patient's medical problem or as a guide for therapy, it is the core of all radiological procedures. The conversion from film-based to digital media for storage, display, and archiving will have a variable effect on the tasks performed by the team members involved in the production and management of the images. For some of the players, these changes will be so profound that a methodology is needed for their management. By simply adding PACS into the equation without a plan for managing these changes, great opportunities to improve the productivity, efficiency, and quality of the center will be lost.

This article will address the value of strategic thinking and provide a discussion of how to use a valuable strategic thinking tool to assist in the management of change, what we have called the "sheet of music." We will then explore how PACS will change the tasks of individual members of the radiology team.

STRATEGIC THINKING

Thinking and planning are activities that we perform every day, and the sequence in which we complete these steps is an important factor in achieving maximum effectiveness. Ideally, we should think about all sides of a problem before planning or implementing a solution. But too often, we forge ahead with elaborate plans before to focusing enough attention on the ultimate goal of our plans. We then have to rethink our options and correct our initial mistakes before resuming our planning and implementation processes.

Strategic thinking tools are helpful because they are easy enough to be understood and applied by radiologists without formal business training. Essentially, the tools communicate at a fundamental level between people. For example, in an imaging center with people of diverse backgrounds, these tools enable the players to cross boundaries and effectively relate at a fundamental level.

The sheet of music tool can be used to present a view of the impact of PACS on the imaging team. The sheet of music is a framework for thinking about the activities of all the members of an organization or department; it is analogous to the conductor's musical score, providing a clear understanding of the parts played by each of the musicians. In any well-run organization, a leader needs the same type of understanding of the roles of each member. Perhaps even more important is a clear understanding by all participants of their roles and the ways these roles complement those of other team members. In this way, duplication of roles is avoided and synergy between the players can be optimized.

The framework for a sheet of music tool is simply a series of columns. Each column has a heading that represents a specific segment of an organization. Below each heading are approximately five areas of activity that are determined to be the major focal areas for the section in question.

A well-managed team will review the sheet of music several times a year. The head of each "section" should be represented at a team meeting. When the dialogue focuses on prioritization within each column and interaction of items within and between columns, the result is a set of activities that fit together (in type and time) that are the most important areas of activity for the organization to meet the customer needs.

SHEET OF MUSIC APPLIED TO THE INTRODUCTION OF PACS

Let us look at several of the specific components needed for implementation of PACS to see what will happen to the work environment with the conversion to a digital PACS. Table 1 summarizes the major changes to individual components that we have identified. It is clear that some will be more affected than others. For example, the film librarian's duties will disappear, as will the transcriptionist. It behooves the organization to be aware of this fact and to develop strategies for the personnel in these categories. Human resource counseling and training will be necessary for most of these individuals. Some will move on to outside positions, and others will be trained to fill new positions created by a PACS-run system.

The technologist will be little affected, though there will be a change in the methods for introducing patient data and accepting an image. The technologist will not need to print film for every case, but may need to do so occasionally for unique needs. However, in most cases where PACS is nearly complete, the technologist is relieved of this task and it is moved into a common central location.

The radiologist will review his/her patient's request and data before reading at the image-reading station. Comparison images will be sorted more easily and will be available rapidly. Medical reports will be dictated using a voice recognition system, which the radiologist will have to become familiar with. Verification will be electronic, and there will be opportunities to consult with colleagues and other clinicians at a distance. All of these activities will require a familiarity with the system and its operations, which will be gained with experience. Radiologist must realize that they may not be as accurate initially when reading softcopy images, compared to the familiar film. Efforts should be taken by management to minimize adjustments.

An all-important role is taken on by the quality control person(s) in a digital department, much of their day-to-day tasks will change. They may be called on to maintain a much less frequently used processor in lieu of maintaining the networks, archives, and display stations.

Maintenance of the networks sometimes falls to the healthcare information systems (HIS) team. Nevertheless, someone in radiology should understand the unique needs for and problems in networking large image data sets, in order to represent imaging needs at the HIS level. This person will have to check the computer displays on a regular basis and will be responsible for making sure that software associated with new or upgraded equipment is validated before being added to the PACS environment. This task may be handled by the industry representatives. But due to multivendor environments, there must be some way of providing in-house oversight.

Finally, the quality control staff are usually responsible for the training of various personnel. In the PC environment, software changes take place constantly. It is important that someone is familiar with and able to explain these changes to users.

Those who perform ancillary functions will have to understand the computer format and the new functions and information that it will provide online. Transportation is one example of a seldom thought of activity that will benefit from electronic assistance.

These generic comments are likely to be true in most situations. The real value of using the sheet of music tool is a greater understanding of how these changes will affect your personnel and how to plan for these changes. Do not underestimate the value of this approach as a communication tool. The process of using the tool is at least as important (if not more so) than the actual action items identified. Maximum benefits from the film-to-PACS conversion will only be gained if management decision-makers consider the effects on individual jobs and tasks, then work to provide better service through a continuous re-evaluation of the processes involved.

Note: This article is adapted with permission of the publisher and authors from Schilling RB, Staab EV. Impact of PACS on the radiology system. Appl Radiol. 1999;28(8):10-13.

STEPS FOR SUCCESS

1. Identify the unique sections or clinical tasks within the department.

2. Identify the responsible person/groups for each section or task.

3. Charge the responsible person/groups to identify five major focus areas of activity for their sections.

4. Create chart listing sections versus activities (tasks).

5. Executive team should review and approve selected tasks.

6. Management team goes over the entire chart, focusing on prioritization and interaction among sections, leading to the action items.

7. The action plan, including all base assumptions, should be monitored and reviewed on a periodic basis.

 

Editor-in-Chief Ronald B. Schilling, PhD
President, RBS Consulting; General Partner, Mi3 Venture Capital Group

Contributing Editors

Edward M. Smith, ScD, FACNP, Professor of Radiology, University of Rochester Medical Center, Rochester, NY

Herman Oosterwijk, President of OTech Inc., Aubrey TX; and adjunct faculty of the University of North Texas Health Informatics Program, TX

Edward V. Staab, MD, Radiology Branch Chief, Biomedical Imaging Program, National Cancer Institute, Rockville, MD

Let Agfa HealthCare help you transition to digital imaging at your own pace.

Call 888-877-AGFA (2432) today to speak to your Agfa representative. www.agfa.com/healthcare/us/

Applied Imaging: Current Trends in PACS is published by Anderson Publishing, Ltd., 1301 West Park Ave., Ocean, NJ 07712. " Copyright 2003 O. Oliver Anderson, Publisher; Elizabeth A. McDonald, Editor

Sponsored by an educational grant from Agfa HealthCare. The views and opinions expressed in this publication are those of the authors and do not necessarily reflect those of the publisher or sponsor. Full and complete prescribing information should be reviewed regarding any product mentioned prior to use.

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