Ergonomic work environment eases PACS reading strain

Greater awareness of health problems related to the use of video display terminals and efforts to prevent them are essential in the modern PACS workplace, according to Korean researchers.

Long-term use of VDTs has created health risks for users, including radiologists, according to Dr. Seong Su Hwang, from the department of radiology at St. Vincent's Hospital, Catholic University of Korea, Suwon. Common clinical problems include eye strain; repetitive motion syndrome; and back, neck, and arm pain. Psychological problems and difficulties related to electromagnetic fields may also be encountered. No concrete evidence of miscarriages and congenital abnormalities has been found in women users.

"PACS has led to work habits that are more sedentary than in the past," Hwang told delegates at the 2006 RSNA meeting. "Radiological interpretation in front of a PACS monitor demands intense use of your eyes at close range over a long duration. This may lead to vision problems, or it may aggravate existing conditions. Eye fatigue and dryness are related to VDT syndrome."

Cumulative trauma disorder and repetitive strain injury may also occur. These conditions involve wear and tear on tendons, muscles, and nerves, resulting from cumulative overuse. Remaining in the same awkward posture for long periods may contribute.

To avoid these problems, Hwang urges PACS developers and users to take full account of ergonomics, which is concerned with the design of working systems in which people interact with machines. Facility administrators should consider implementing several recommendations:

• Fit the reading-room environment to the radiologists, not the other way around.

• Make day-to-day working conditions comfortable.

• Be cautious about improving ergonomics; what is right for one person may not be right for another.

Reductions in any discomfort during reading practice indicates the right path.

Users should find a healthy body posture during reading. Sitting slightly reclined with the torso at a high angle of 110 degrees may reduce disc pressure by 20% to 30% and muscle activity by 30% to 40%. Keeping your head balanced and your shoulders relaxed and comfortable may also help, as may straightening your wrists during typing and ensuring that your forearms and thighs are parallel to the floor, Hwang said.

Having a chair with adequate support and using a footrest can also reduce lower back pain. A radiologist's chair should have adjustable seat and arm height, good lumbar support, a rounded front edge, and five wheeled legs for stability.

"For the most comfortable viewing position at PACS monitors", Hwang said, "position the top of the screen at or just below eye level and maintain a comfortable eye/monitor distance of generally an arm's length. Decrease the glare on the screen, use an antiglare screen if necessary, close blinds, tilt the screen backward slightly, dim the lights, keep the monitor ventilated and clean, and place the VDT perpendicular to the window. Take minibreaks between reading sessions and alternate between standing and sitting."