Foot pedals and joysticks threaten keyboard and mouse

June 2, 2005

Keyboard and mouse, the basic tools for image manipulation in the digital environment, were tossed out with surprisingly good results in a pair of research studies presented Thursday.

Keyboard and mouse, the basic tools for image manipulation in the digital environment, were tossed out with surprisingly good results in a pair of research studies presented Thursday.

A study from Geisinger Medical Center found that replacing the mouse and keyboard with a computer game controller reduced time and distraction associated with taking the reader's eyes off an image and looking down at a keyboard to make adjustments.

A Stanford University study, with assistance from GE, evaluated 10 video system manipulation devices for viewing large multislice CT exams. It found that foot pedals combined with a joystick could provide a good alternative to traditional tools.

The keyboard dates back to the 1800s, and the mouse emerged in the 1960s. They have become the default tactile interface elements of digital image manipulation. But as volumes grow, so has dissatisfaction with these devices, and researchers have begun to evaluate alternatives.

Their concerns reflect ergonomic, speed, and quality issues. Time spent looking down and refocusing on a keyboard is time spent away from the image, and this potentially harms both efficiency and quality. Some radiologists are also concerned about repetitive stress injuries from keyboard and mouse use.

The Geisinger study evaluated the use of a Belkin Speedpad/five-button mouse combination for interpreting head CT scans on a PACS workstation. The Speedpad could take up to a week to learn, but it can be programmed with macros, said Dr. Ben Johnson, who presented the study.

Preliminary data show fewer distractions with the Speedpad mouse as compared with the keyboard and three-button mouse combination, Johnson said. The need to look at the interface device declined from 11.8 looks per case to 2.6 with the Speedpad. The use of dropdown menus decreased from 3.7 times per case to 0.1.

The Stanford study did not compare the alternative devices to the keyboard/mouse combination but still concluded that mouse/trackball approaches common at many workstations may not be optimal. Radiologists who reviewed all 10 systems preferred a joystick and foot pedal combination under most circumstances. When reviewing cine images, their preference was for foot pedals with a jog shuttle device.

Foot pedals are particularly useful when navigating through a stack of images, the researchers said.