Accelerated adoption of digital imaging products today accounts for a major portion of healthcare spending - more than $9.2 billion in 2008 according to iData Research Inc, Vancouver, BC, Canada - as demand by our aging population for MRIs and CAT (CT) scans continues to ramp up. Furthermore, the Government Accountability Office reported that Medicare spending on imaging services from 2000 to 2006 more than doubled to $14 billion. It is estimated that 28% of the U.S. population will turn 65 between 2010 and 2020.

Also growing is the demand for home or mobile healthcare equipment that includes monitors and meters for the heart, blood pressure, and glucose levels. These devices can stream live data to rugged medical tablet PCs for mobile healthcare professionals. In addition, “medical tourism” indicates a worldwide understanding of markets that offer high-tech devices, which entice patients to be international travelers in search of better and more affordable procedures.

Integral to these trends are requirements for advancements in storage for medical devices. Of particular importance for storage are the individual device requirements mandated for the Heath Insurance Portability and Accountability Act (HIPAA), as well as Food and Drug Administration (FDA) qualifications for medical media servers that are required to stream live patient data with no interruptions. It is obvious that storage systems must be up to the task to match these tough requirements with the high performance, high reliability, long product life, and the lowest total cost of ownership needed by today's medical equipment OEMs.

Optimal storage choice depends

Solid-state-drives (SSD) and hard-disk-drive (HDDs) advancements impacting capacity (higher), performance (better), size (smaller) and power consumption (lower), have given designers a broad range of solutions from which to choose. However, the choice between SSDs versus HDDs largely depends on where devices will be used. Within certain medical devices the storage option may require extra ruggedness. For example, home healthcare devices are subjected to greater user error and abuse than those used in a traditional hospital or professional healthcare setting. In these cases, SSDs are optimal harsh environment alternatives to HDDs. For large digital data base storage, HDDs offer the lowest cost per gigabyte ratio on the market.

System ruggedness is also a contributing factor to medical- device usage models. “Always-on” devices often require a higher level of ruggedness than do “non-24/7 usage” models for harsh environments. The good news is that there are integrated advanced storage technologies now available in SSDs to overcome drive wear-out associated with intensive write-read usage models.

Storage systems must also complement embedded computing platforms such as CompactPCI and AdvancedTCA, used in many medical applications. SSDs are growing in popularity for medical designs because they match these computing architectures with high availability, inherent ruggedness, ease of maintenance and upgradability, and low power operation.

Power disturbances are also of great concern, or should be, to medical- device makers. Drive and data corruption from ungraceful power downs, power surges, spikes or brownouts are estimated to be the leading cause for storage system field failures. Advanced storage technologies with integrated voltage protection in SSDs can eliminate these field failures, protecting patients while saving thousands of dollars in unscheduled downtime.

Product longevity and security

As indicated previously, patient data and record storage must now adhere to new HIPAA longevity and security requirements. Unauthorized access security concerns are also driving designers of medical devices to address ways to protect patient data. In addition, there are specified retention requirements for various types of medical information that can stretch up to 21 years for pediatric records, or beyond the lifetime of adult patients.

Another key consideration for product longevity is storage endurance; how long will an SSD last in an application? In the past, capacity was typically the main factor in determining lifespan in a given application. Since there weren't tools to measure or forecast SSD life, “overprovisioning” - adding more capacity than was needed - solved the issue.

Today, tools to measure SSD lifespan are available and using them can be a critical factor in storage selection; not only to determine what applications best suit SSDs, but also to guarantee performance with no unscheduled downtime within rugged imaging and computing environments. In addition, methodologies are now available to accurately forecast SSD life in months or years. Helping designers with this tough evaluation, Western Digital has developed LifeEST, a new metric to measure SSD technology that determines the number of “write years per GB” the SSD can achieve. OEMs can verify the endurance of an SSD using the equation on the previous page.

Even more effective in evaluating storage endurance are integrated technologies to monitor actual drive useable life. Because storage systems must outlive the devices in which they are embedded and due to the long, expensive qualification process for medical equipment that most often requires FDA approval, failure is not an option. SSDs with advanced storage technologies now offer the capability to monitor drive usage in real-time with no downtime to ensure long product life.

It's important to remember that storage options for medical devices and equipment are just as diverse as the many drivers and application trends fueling the overall healthcare market. In all cases, medical OEMs need to select the “right hammer for the right job” when it comes to storage. To select the optimal storage solution, it is important to match the storage option with a medical device's physical location and environment. Equally important is having a thorough understanding of its usage model to guarantee high performance and reliability, long product life and the best possible patient care, all within the device maker's storage budget.

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