Surgeons weigh cost, function in creating a teleradiology system

With some careful planning, an orthopedic practice can get ‘wired’ to receive and send images without breaking the bank.

Issue: June 2005

One of the attractions to digital X-ray systems is their ability to electronically transmit patients’ radiographs from one location to another.

This process, known as teleradiology, has the potential to help orthopedists improve patient care, particularly when the responsible orthopedic surgeon is at a remote location from the patient and his/her radiographs.

According to William M. Ricci, MD, orthopedic surgeon at Barnes-Jewish Hospital at Washington University in St. Louis, there are several components of an effective teleradiology system, including the following:

a sending station, where images are acquired, digitally encoded and transmitted;
a transmission network that provides a pathway for image data to pass from the sending station to the receiving station;
a storage device to archive the digital image data (ie, locally on the computer hard drive, or dedicated servers);
a viewing station to review images (including standard PC monitors, higher-quality monitors for dedicated teleradiology workstations that have a resolution of at least 1600 × 1200 pixels, or “diagnostic quality” monitors that are often larger than 28 inches and have at least 2000 × 2000 pixel resolution for extremely detailed viewing work); and
software that provides the ability to manipulate the digital images.

Sending station

To send and receive image data, images must be saved in a digital format appropriate for data transmission between computer workstations. CT, MRI, ultrasound and nuclear medicine images are typically acquired in a digital format, whereas plain radiographs are normally obtained in an analog format.

“Digitization” of analog data is usually accomplished by scanning, Ricci said during an instructional course lecture at the American Academy of Orthopaedic Surgeons 72nd Annual Meeting. Two methods of direct digital capture of plain radiographic images include computed radiography (CR) and direct radiography (DR).

“We determine resolution by the number of pixels (short for picture elements),” he said. Typical resolution matrix sizes are 512 × 512 (512 pixels wide by 512 pixels high), 1024 × 1024 and 2048 × 2048. Resolution is also determined by depth (ie, the number of shades of gray per pixel). Typical gray scale depths are 256 (eight computer bits deep) to 4096 (12 computer bits deep) shades of gray.

A matrix of 2000 × 2000 pixels with a depth of 4096 shades of gray (12 bit) is required for the diagnosis of subtle skeletal radiology, he said. This level of resolution is called “diagnostic quality.”

However, “I don’t think that level [of detail] is necessary for most orthopedic fractures,” he said. “Even if it isn’t 2000 pixels, it’s still better than the current standard of practice, which is verbal communication only.”

Another thing to remember is that high resolution (ie, smaller pixel size and more shades of gray) “means more accurate reproduction, but it also means larger file size, more expensive equipment, more storage media and increased transmission times,” Ricci said.

Which system is best for you?

Ricci detailed three model teleradiology systems that orthopedic practices or departments are using to digitize and transmit files.

The simplest system, known as the “homemade” system, is effective for individual physicians who want to start a teleradiology system but do not require diagnostic accuracy or a high level of convenience, he said. This system uses existing equipment and technologies, and standard X-rays are manually digitized with a scanner or digital camera. Images are transmitted via established networks or via e-mail with costs associated with Internet access fees totaling about $10 to $100 a month.

Orthopedists using the homemade model can also use standard personal computers and monitors for their workstations to send and receive images, which helps cut down on costs, he said. Likewise, image manipulation software bundled with the existing computer or additional consumer image manipulation software can be used to enhance viewing, costing anywhere from $0 to $800.

The total expense of such a homemade system can range from $500 to more than $25,000 depending on the options chosen (excluding Internet access fees), he said.

Dedicated teleradiology system

In the dedicated teleradiology system, “The hospital or practice has a system that essentially automates many of the steps and provides high-quality images,” although these images are not necessarily diagnostic quality, Ricci said.

In addition, such a system offers greater storage options and dedicated software for sending and viewing images than the homemade system. Standard X-rays are typically digitized into DICOM (Digital Imaging and Communications in Medicine) format using a high-quality, high-speed, multiple-page, 12-bit scanner costing anywhere from $10,000 to $50,000.

“Having your own dedicated software helps automate the process of compression, encryption and transmission to a secure server,” he said. A service agreement with the vendor dictates how many images can be stored and for how long.

Owners of this type of system will need a viewing station, which can be any computer with Internet access. This can cost up to $5000 for a dedicated station with a high-quality monitor, or it can cost nothing if the user chooses to use existing hardware.

Users may also want to use software from the viewing station, which is often Web-based, to provide password protection and manage manipulation capabilities. This can cost $10,000 for the software license.

The total cost of such a system ranges from $20,000 to $70,000 plus up to $2000 in monthly fees.

Integrated system: Looking for more

A high-end, sophisticated system for large practices or institutions that wish to phase out standard plain radiography for digital will need a computed radiography machine (about $100,000 to $150,000) or digital radiography machine (about $400,000 or more). Software ($50,000) that processes the DICOM data send it to a transmission server ($15,000), which can distribute the images to directly connected workstations within the institution or practice ($5000 to $7000 each), Ricci noted in his lecture handout.

For remote viewing via the Web, images are automatically compressed to reduce transmission time. Owners will also need a dedicated onsite storage system for permanent image archiving (approximately $8000 per 500 Gb). Finally, the owner should purchase onsite or offsite backup systems ($10,000) in case of system failure.

The total cost for these high-end systems, with one sending workstation and four viewing stations, can range from $200,000 to more than $500,000, he said.

Ricci believes that the quality of teleradiology systems will continue to improve in the next few years, while the cost of some components should decrease. Furthermore, “The trend toward direct digital capture of radiographs, digital radiography and computer radiography will likely continue,” he reported.

Among the specific improvements will be the development of enhanced compression algorithms, which means the required storage size required will be reduced without significant loss of image quality, and the data transmission time will be reduced. Also, transmission should improve with increased bandwidth and cheaper and more convenient transmission of image data.

Finally, surgeons may be able to use laptop computers with wireless connections and handheld devices such as PC-based and Palm-based PDAs to send or receive radiographic image data in the near future, he said.

For more information:

Ricci WM, Tipirneni K. Instructional course: Digital X-ray for the orthopaedic surgeon. Presented at the American Academy of Orthopaedic Surgeons 72nd Annual Meeting. Feb. 23-27, 2005. Washington.