Epithelial Responses to Rubbing-Related Mechanical Forces

Abstract

These results indicate a statistically significant mechanical trauma to the epithelium after 15 seconds of light to moderate rubbing. With reference to the rheological properties of the cytoskeleton, an attempt to explain how the epithelium could lose and recover thickness has been made. Apart from cell flattening, displacement from the rubbed area of intercellular water, cytoplasm from ruptured cells, chains of wing cells, and mucin are suggested as possible thinning mechanisms. Extraneous eye rubbing may adversely alter the results obtained with pachymetry, videokeratography, wavefront aberrometry, refraction, and results obtained with orthokeratology contact lenses.

Recurrence or Re-emergence of Keratoconus – What is the Evidence Telling Us? Literature Review and Two Case Reports

“…/ Bergmanson, et al alterations from wound healing in the anterior limiting lamina, stromal dehiscences in the anterior limiting lamina, lamellar slippage, and loss of biomechanical rigidity. 23,24,26 Thinning and loss of rigidity may predispose a biomechanically weakened corneal region to cone formation in response to intraocular pressure-distending forces, as in the case of eye rubbing. 24,27 Future research would be welcome to provide further understanding of how ocular rubbing could contribute to manifestation of corneal ectasia.…”

Corneal Responses to Eye Rubbing with Spectral Domain Optical Coherence Tomography

“…Therefore, a possible explanation for this contrasting result could be due to the different application of measuring techniques and rubbing forces in our study to that of McMonnies. 7 A final approach to solve this problem would bring a new comparative study using both devices on the same subjects. On the other hand, Kalogeropoulos et al 35 found the results that are similar to our study, where they demonstrated epithelial thickness profile was unaffected after 10 minutes of eye rubbing measured in subjects with normal corneas using modified optical pachometer.…”

“…Significant increase in surface regularity index and a small amount (0.5 diopter) of induced astigmatism has been reported in subjects immediately after 60 seconds of experimental eye rubbing. 13 Current Eye Research a significant epithelial thickness reduction of 18.4% in response to compressive and shearing forces associated with 15 seconds of circular pattern rubbing over the cornea measured using Holden-Payor optical pachometer, 7 which inspired us to perform this study to evaluate the effects of eye rubbing on thickness profile of the cornea using SD-OCT.…”

“…McMonnies et al 7 have proposed that an increased intraocular pressure (IOP) and hydrostatic pressure within epithelial cells under excessive mechanical stress exerted by combined compressive and distending forces during eye rubbing may induce epithelial cell flattening and subsequent cell trauma resulting in displacement of cytoplasm, chains of wing cells and mucin that contributes to epithelial thinning.…”

Effects of eye rubbing on the levels of protease, protease activity and cytokines in tears: relevance in keratoconus

“…Further care was taken by the subjects to adapt to the circular eye rubbing movement, applying constant pressure toward the centre of the cornea. Instructions were also given to the subjects to maintain a steady central fixed gaze position with the contra‐lateral eye opened during eye rubbing to control fixation and assist in achieving central corneal rubbing …”