Increasing the ambient illuminance, using an appropriate type of monitor, improving corrected visual acuity, and using contact lenses rather than glasses could help decrease reading-induced fatigue in male radiologists, according to a study published in the November issue of Academic Radiology.

As imaging modalities continue to evolve, radiologists have to read more images in less time, often resulting in severe reading-induced visual fatigue.

“Values representing visual fatigue and other types of fatigue in the central nervous system (CNS) have been reported to be significantly changed by reading of digital images displayed on an electronic display device (soft-copy reading),” wrote the study’s author, Yoichiro Ikushima, MS, of Kyushu University in Fukuoka, Japan, and colleagues.  

Ikushima and colleagues thus designed a study to investigate the factors that affect fatigue caused by routine soft-copy reading in order to identify effective countermeasures.

The researchers evaluated two types of fatigue—fatigue in the CNS and subjective visual fatigue—with a critical fusion frequency test and a questionnaire given to 17 male radiologists before and after soft-copy reading.

Twenty hypothetical factors involving personal characteristics, time required for reading, content or amount of reading, and reading environment were determined to have an effect on reading-induced fatigue. The effects of the detected factors on fatigue were examined based on coefficients of the dominant factors in multiple regression models.

The study’s results revealed that fatigue in the CNS decreased with a higher corrected visual acuity and a higher ambient illuminance in a reading room. Visual fatigue was alleviated when there was a larger difference between the brightness of the monitor and surrounding surfaces. Fatigue tended to be more severe when glasses were worn instead of contacts.

It is necessary for radiologists to make these adjustments during reading, as a decline in diagnostic accuracy could by caused by the fatigue associated with soft-copy reading, the authors said.