Internet neighborhood proves safe for digital images

Radiologists reluctant to use the Internet to transmit digital images for fear of losing image quality or violating patient confidentiality can take heart from a Cleveland Clinic study.

The paper, presented at the November RSNA meeting, concluded that not only is the Internet a fast, safe environment for digital images, it is also far less expensive than traditional telecommunication methods.

The study compared the reliability and speed of electronically transmitting CT and MR scans between PCs running commercially available viewers over the following networks:

• dedicated 10BaseT, point-to-point T1 line;

• 64 Kbps ISDN (integrated services digital network) line, otherwise known as POTS (plain old telephone service); and

• over the Internet, with both PCs connected to an Internet service provider (ISP) by a T1 line.

Dedicated (T1) lines or local phone lines are typically used by hospitals and physicians, since Internet reliability until now has been an open issue.

Nine MR and six CT exams were randomly chosen from the clinics archive, with the number of images in each case ranging from 26 to 256. Demographic data was stripped to maintain patient privacy.

The study showed the quality of the images to be the same on all systems, with no loss of data. Transmission speeds were likewise comparable. Confidentiality concerns were addressed by the same access restrictions and encryption schemes in common medical use.

The speed of transmission over the Internet (five to 12 seconds per MR image and five to 45 seconds per CT image) compared favorably with the speed of transmission over frame relay (T1) and ISDN lines.

"Internet transmission of images is a reliable method of transmitting CT and MR images," said Dr. Michael P. Recht, a musculoskeletal radiologist and head of the section of e-radiology at the Cleveland Clinic Foundation. "Internet speed of transmission compares favorably with dedicated telecommunication lines, although it can vary depending on the time of day."

There was no image degradation during Internet transmission, and no images were lost, Recht said.

The Internet offers substantial cost savings, a consideration important to those smaller hospitals and remote clinics to whom the benefit of digital second opinions most appeals. It costs Cleveland Clinic Foundation $7000 a month for a high-speed telecommunications line to one specific clinic, according to Recht. Internet service provider fees, on the other hand, are typically a fixed, low monthly charge, usually less than $50.