Original article
Impaired functional visual acuity of dry eye patients

https://doi.org/10.1016/S0002-9394(01)01365-4Get rights and content

Abstract

PURPOSE: To report dry eye patients’ functional visual acuity, which was measured after sustained eye opening for 10–20 seconds, as a simulation of visual function of daily acts of gazing, which is defined as looking at an object with involuntary blink suppression.

METHODS: Interventional clinical nonrandomized comparative trial. We measured ordinary best-corrected visual acuity and functional visual acuity in non-Sjögren’s syndrome (non-SS, N = 10) and Sjögren’s syndrome (SS, N = 12) patients and in normal controls (N = 8), prospectively. Surface regularity index (SRI) of corneal topography was also measured under routine circumstances and after sustained eye opening. Blink rates while gazing were measured during reading in another 28 dry eye patients and during driving in another 8 normal controls.

RESULTS: Functional visual acuity did not change (1.27–1.16) in normal controls, but decreased significantly from 1.18–0.336 in non-SS patients (P = .0007) and from 1.15–0.228 (P < .00001) in SS patients. SRI after sustained eye opening increased in non-SS (P = .032) and SS patients (P = .0007), but not in the normal controls. Blink rates during reading (P < .001) and driving (P = .012) were significantly decreased from baseline blink rates.

CONCLUSIONS: This study shows that the visual function of dry eye patients becomes abnormal with ocular surface irregularity when the eye is kept open for 10–20 seconds. Our data indicate impaired visual function in dry eye patients while gazing. Functional visual acuity may be important in daily activities.

Section snippets

Participants and inclusion criteria

For functional measurement of vision and ocular surface regularity, we recruited a consecutive series of dry eye patients, including non-Sjögren’s syndrome-type dry eye (non-SS, N = 10, 2 males and 8 females, average age 51.2 ± 18.3 years), Sjögren’s syndrome-type dry eye (SS, N = 12, all females, average age 54.8 ± 10.4 years), and normal controls (N = 8, 1 male and 7 females, average age 53.8 ± 6.84 years).

Dry eye patients fulfilled the diagnostic criteria of deteriorated tear function and

Visual acuity and corneal surface regularity after sustained eye opening

Ordinary best-corrected visual acuity of non-SS dry eye patients, SS patients, and the normal controls during free blinking was 1.18, 1.15, and 1.27, respectively (Table 1). Ordinary visual acuity examinations revealed no differences among the three groups (P = .21). However, in the dry eye patient groups, functional visual acuity after sustained eye opening without blinking for 10–20 seconds decreased significantly to 0.366 (P = .0007) in the non-SS group and to 0.228 (P < .00001) in the SS

Discussion

In this study we measured functional visual acuity when the subjects eyes had been open for 10–20 seconds. We were surprised to find that functional visual acuity in the dry eye groups decreased significantly with increased SRI, but not in any of the normal controls. Ordinary best-corrected visual acuity in all subject groups was within normal limits without statistical significance accompanied with ordinary SRI. Ordinary SRI in dry eye patients was higher than the normal group without

References (17)

There are more references available in the full text version of this article.

Cited by (0)

Supported by grants from the Medical School Faculty and Alumni Grants of Keio University Medical School, Tokyo and the Hightech Research Center at Tokyo Dental College, Chiba, Japan.

View full text