Diurnal Variation of Visual Function and the Signs and Symptoms of Dry Eye

Abstract

Subjects with dry eye experience significant diurnal variations of visual function and ocular surface physiology. These daily rhythms should be considered when designing clinical trials and when quantifying disease severity.

Basal values, intra-day and inter-day variations in tear film osmolarity and tear fluorescein clearance

“…Also, it has been found a daily variation of visual function, keratitis, conjunctival hyperemia and symptoms in DED subjects. 8 The present study has some limitations as the number of subjects included or the criteria used for selecting subjects. Although they were focused to include young healthy subjects without ocular surface disease, there were some subjects that could be classified as normal or mild DED.…”

“…Most tests are not standardized in the manner in which they are performed, and the tests results are not well correlated with the reported symptoms of DED. [3][4][5][6][7] In addition, some tests seem to be altered by circadian rhythms, 8 which may be related to changes in the ocular surface symptoms throughout the day; in fact, an evening worsening of visual function and symptoms have been described in patients with DED. 8 Due to the unsatisfactory results provided by the currently available diagnostic tests, some new tests have been developed recently, e.g.…”

“…[3][4][5][6][7] In addition, some tests seem to be altered by circadian rhythms, 8 which may be related to changes in the ocular surface symptoms throughout the day; in fact, an evening worsening of visual function and symptoms have been described in patients with DED. 8 Due to the unsatisfactory results provided by the currently available diagnostic tests, some new tests have been developed recently, e.g. measurement of the tear meniscus with optical coherence tomography, 9 and others have been improved to allow easier use in the clinic; for example, tear osmolarity measurements, which had been primarily a laboratory test, is more accessible clinically for assessing dry eye due to recent technologic advances.…”

Corneal Fluorescein Staining Correlates with Visual Function in Dry Eye Patients

“…The stability and regularity of the ocular surface are thought to be the major factors in forming clear visual images. [1][2][3][4][5][6] The surface regularity index (SRI) and surface asymmetry index (SAI) measured by corneal topography, wavefront, and tear stability analyses systems have been shown to be significantly worse in patients with dry eyes than in normal subjects. [7][8][9][10][11] Dynamic changes in the tear film have been the focus as the cause of visual deterioration.…”

Cataract Surgery and Dry Eye

“…Currently, the majority of clinicians probe into the patient's symptomatology regularly and the clinical tests most routinely used to evaluate severity of dry eye are tear break up time and corneal staining (Smith et al, 2008). Finally, it is important to remember that diurnal variation is known to occur in symptomatology and clinical signs, and to affect the visual function capabilities of dry eye patients (Abelson et al, 2009;Walker et al, 2010).…”