According to a report published Online First by Archives of Ophthalmology, one of the JAMA/Archives journals, frequent visual field testing may be linked to earlier detection of the condition’s progression in patients with glaucoma.

Background information of the article states that visual field testing is the most-used option for monitoring progression in patients with glaucoma. The authors comment,

“Estimating rates of progression can help identify patients who are progressing at a faster pace and are therefore at serious risk of developing visual disability during their lifetime. These patients can be subjected to more aggressive treatment or more frequent follow-up.”

They continue that frequent visual testing however may not be appropriate or useful for every patient.

Evidence based on real patient data may not support a recommendation for a minimum of three yearly examinations to achieve optimal sensitivity and specificity for detection of clinically significant rates of progression.

Kouros Nouri-Mahdavi, M.D., M.Sc., and his colleagues from the Jules Stein Eye Institute, University of California in Los Angeles examined data from the Advanced Glaucoma Intervention Study (AGIS), and selected 468 eyes of 381 patients aged 35 to 80 years who suffered from primary open-angle glaucoma that no longer responded to the maximal tolerated medical treatment. The patients had a baseline visual field AGIS score of 16 or less, at least three years of follow-up and at least 10 visual field examinations with a reliability score of two or less.

All visual field tests performed within the first year of follow-up as well as the last available visual field tests were included in the study. The researchers also assembled a low-frequency data set by deleting, for one group, every other visual field test from the second year of follow-up onward; and a high-frequency data set for which none of the visual field tests were deleted. A comparison took place between the two data sets as to how many eyes progressed and the time-period to progression.

Participants in the study were observed for an average of nine years with the overall range starting from 3.2 up to 13 years. The average number of high-frequency visual field examinations carried out was 20 with an average of 12 low-frequency visual field examinations data sets. Investigators therefore concluded that the high-frequency data set was more likely to detect progression. They also detected improvement in some eyes. The results did not alter significantly when data were censored (curtailed to account for partially unknown values) at five years.

In a summarizing statement the authors said,

“We found that a twice-yearly schedule of visual field testing resulted in earlier detection of glaucoma progression compared with a yearly schedule, especially with global trend analyses. Validation of these findings in other patient populations would be desirable. Our results have significant health care policy implications with regard to determining the frequency of visual field testing in patients with glaucoma.”

Grace Rattue