Compared with hard-copy radiographs, digital images require less physical storage space, allow rapid storage and retrieval,
and avoid loss in image quality over time or with duplication. Several options for image storage systems are available, including
on-site secure redundant storage, Network-Attached Storage, Storage Area Networks, recordable removable media, and off-site
Regardless of the storage system used, make sure your digital images are stored in a nonproprietary format. Human medicine
has adopted the Digital Imaging and Communications in Medicine (DICOM) standard. Think of DICOM as a language that all computers
speak so they can communicate effectively. The American College of Veterinary Radiology supports and recommends DICOM as the
digital imaging standard in veterinary medicine. Storing images in a DICOM format will help guard against problems with future
data transfer (see the article "An introduction to DICOM" ).
Seth Wallack, DVM, DACVR
ON-SITE SECURE REDUNDANT STORAGE
With this method, a veterinary hospital must purchase a server with redundant storage such as a RAID (Redundant Array of Independent
Disks) server or a direct attached storage system.
By storing data on more than one disk, RAID servers ensure that no data are lost if one disk in the array fails. If one disk
fails, it can usually be exchanged without interrupting normal system operation or losing data. Well-built RAID servers typically
have an audible alarm that alerts personnel if a disk fails. RAID servers have different configurations, and a RAID 5 server
or higher is recommended because of high reliability and high performance.
On-site image storage allows immediate image access and hospital-wide image distribution, especially when partnered with a
Picture Archive Communication System (PACS). RAID systems cost $5,000 to $20,000 and have ongoing maintenance costs, which
include hiring information technology (IT) personnel. On-site RAID servers do not protect images from disasters such as floods,
fires, server theft, or building destruction.
Proper Image Storage: A Legal and Ethical Requirement
Direct attached storage
Direct attached storage consists of separate cabinets that contain a RAID 5 or higher configuration. The storage capacity
is limited only by the number of slots available and the configuration used. Theoretically, it is possible to create a storage
unit that contains up to 16 500 GB drives in RAID 5, 6, 10, or 50 configurations for varying degrees of backup. Data on a
direct attached storage system are always accessible, and backup can be continuous. In addition, these systems can be partnered
with a storage software program.
Unfortunately, even with the costs of disks always decreasing, direct attached storage would cost about $10,000 to implement.
And although redundant, direct attached storage systems can experience catastrophic failure with complete loss of stored data.