Diurnal Variation of Ocular Hysteresis, Corneal Thickness, and Intraocular Pressure

Abstract

Diurnal variation of CH was not detectable in healthy Asian eyes. The diurnal fluctuation of IOP appears not to be associated with CH. However, CRF was increased a few minutes after sleeping, a change that was correlated to the changes of IOPg.

Interaction between diurnal variations of intraocular pressure, pachymetry, and corneal response to an air puff: Preliminary evidence

“…Kida et al 3 found that corneal hysteresis (CH) measured with a dynamic bidirectional applanation device (Ocular Response Analyzer, Reichert Technologies) showed an inconsistent 24-hour variation, with no evidence of being influenced by 24-hour changes in IOP. A similar finding was reported by Shen et al 4 However, Gonz alez-M eijome et al 5 found that changes in CH measured with the same device correlated well with changes in IOP, suggesting that diurnal IOP variations could be related to changes in corneal biomechanics. Likewise, Lau and Pye 6 suggested that diurnal variations in central corneal thickness (CCT) and corneal resistance factor (CRF) measured with the dynamic bidirectional applanation device may significantly affect the tonometry measurements.…”

Intraocular Pressure During Robotic-assisted Laparoscopic Procedures Utilizing Steep Trendelenburg Positioning

“…First, there exists a diurnal variation of IOP, known to be 3 to 4 mm Hg in healthy subjects, with the highest values typically in the early morning. 13,24,25 There was slight variability of start times of the surgeries. With the small diurnal fluctuation of IOP relative to the large increase described in the results, it is unlikely that diurnal variation significantly changes the findings.…”

Repeatability of Ocular Biomechanical Data Measurements With a Scheimpflug-Based Noncontact Device on Normal Corneas

“…The age dependency of the biomechanical parameters is also well known from the literature, 5, [20][21][22][23] conforming that the elastic properties of the cornea are changing with age. 23 On the contrary, others found that CH and CRF are very independent of age.…”