The Effect of Contact Lens Wear on the Cellular Morphology of the Lid Wiper Area

Perioperative Care of the Patient with Eye Pathologies Undergoing Nonocular Surgery

The authors reviewed perioperative ocular complications and implications of ocular diseases during nonocular surgeries. Exposure keratopathy, the most common perioperative eye injury, is preventable. Ischemic optic neuropathy, the leading cause of perioperative blindness, has well-defined risk factors. The incidence of ischemic optic neuropathy after spine fusion, but not cardiac surgery, has been decreasing. Central retinal artery occlusion during spine fusion surgery can be prevented by protecting eyes from compression. Perioperative acute angle closure glaucoma is a vision-threatening emergency that can be successfully treated by rapid reduction of elevated intraocular pressure. Differential diagnoses of visual dysfunction in the perioperative period and treatments are detailed. Although glaucoma is increasingly prevalent and often questions arise concerning perioperative anesthetic management, evidence-based recommendations to guide safe anesthesia care in patients with glaucoma are currently lacking. Patients with low vision present challenges to the anesthesia provider that are becoming more common as the population ages.

Filaggrin Expression in the Lid Margin During Contact Lens Wear

AIM

To investigate the expression of the keratinization-related protein, filaggrin, in the lid margin epithelium of contact lens (CL) wearers compared with nonwearers.

METHODS

This was a cross-sectional study of 100 individuals with different exposures to CL wear: short, moderate, and long experience; previous CL wearers; and nonwearers as controls. Impression cytology samples were collected from the lid wiper (LW) area of the central upper lid margin. After fixing, an equal, random sample was selected from each group (n=13) for immunocytochemistry analysis using antihuman primary anybody (mouse filaggrin), then stained with secondary antibody (fluorescein isothiocyanate-conjugated donkey anti-mouse immunoglobulin G horseradish peroxidase) to detect filaggrin. Imaging was performed with the 3i-Vivo 2-photon microscope equipped with a Zeiss 20×-objective and SlideBook-reader software.

RESULTS

Sixty-five samples from 65 participants (37 women; mean age±SD: 25.1±4.1 years) were collected. Filaggrin was detected in all 65 randomly selected immunostained marginal epithelium samples. All samples were similar in showing patchy areas of filaggrin immunostaining, regardless of CL wear, symptoms or epithelium morphology. Because the filaggrin immunostaining showed similar patterns across almost all the observed samples, comparison between subject groups was impractical. The presence of filaggrin in the healthy LW was additionally confirmed by an independent laboratory.

CONCLUSION

Filaggrin expression seems to be a normal part of epithelial cell differentiation in the lid margin and may not be a useful keratinization/stress biomarker in the marginal epithelium. Investigating other keratinization biomarkers that are not detected in the normal mucocutaneous junction/LW may help to understand the keratinization nature of LW epithelium changes in CL wearers.

Natural course of lid wiper epitheliopathy (LWE) in symptomatic contact lens wearers

PURPOSE

To establish the time course of lid wiper epitheliopathy (LWE) in established CL wearers after a single day (6-10 h) of daily disposable contact lens (CL) wear, the following day post-CL removal and 1-week after CL discontinuation.

METHODS

Twenty-one symptomatic (CLDEQ-8 score ≥ 12) habitual wearers of MyDay® silicone hydrogel daily disposable were included. LWE staining was assessed prior to CL wear (Visit 1, V1) using semi-automated analysis after instillation of two drops of 1 % lissamine green (10 μL) that were applied to the superior bulbar conjunctiva. LWE measurements were repeated after 6-10 h of continuous CL wear (Visit 2, V2), post-CL removal the following day (Visit 3, V3) and after 1-week CL discontinuation (Visit 4, V4). At each visit, ocular symptoms were evaluated using the SPEED-8 questionnaire and set of 0-100 visual analogue scales (VAS).

RESULTS

LWE showed no significant changes after 6-10 h of continuous CL wear (p = 0.536), post-CL removal the following day (p = 0.677) or following 1-week of CL discontinuation (p = 0.478). Analysis revealed a significant improvement in symptomatology between V1 and V2 (SPEED-8, p < 0.01) and also improvements in the 0-100 VAS scores between V2 and V4 for average daily dryness (p < 0.01), end-of-day dryness (p < 0.01) and frequency of end-of-day dryness (p < 0.05).

CONCLUSION

The present data suggest that the etiology of LWE is multifactorial and the sole intervention of temporarily discontinuing CL wear does not lead to resolution of these clinical signs.

Ocular surface microvascular response and its relation to contact lens fitting and ocular comfort: an update of recent research

This review examines vascular responses in the ocular surface to contact lens wear and its relation to lens fitting characteristics and contact lens-related discomfort. A search of PubMed was performed to find original research in English, within the past 10 years, that studied the ocular surface, including lid-wiper vascular responses to the lens. The interaction between the lens and ocular surface triggers vascular responses, impacting the lens fitting and contact lens-related discomfort. Contact lens-related discomfort is a multifactorial event, which is affected by lens characteristics. Overall, contact lenses with low modulus and a relatively tight fit produce significant ocular comfort. If an appropriate lens fit is achieved, lens fitting characteristics may not play a critical role in contact lens-related discomfort. On the other hand, the pathogenic and vascular changes of lid-wiper vascular responses appear to play an essential role in developing contact lens-related discomfort, in concert with reactions of the cornea (compression and staining) and conjunctiva (indentation and staining). Robust evaluation of lid-wiper changes at the cellular and microvascular level may hold the key to better understanding the mechanism of contact lens-related discomfort and reveal strategies for eliminating lid wiper epitheliopathy and improving ocular comfort in contact lens wearers.

CLEAR - Effect of contact lens materials and designs on the anatomy and physiology of the eye

This paper outlines changes to the ocular surface caused by contact lenses and their degree of clinical significance. Substantial research and development to improve oxygen permeability of rigid and soft contact lenses has meant that in many countries the issues caused by hypoxia to the ocular surface have largely been negated. The ability of contact lenses to change the axial growth characteristics of the globe is being utilised to help reduce the myopia pandemic and several studies and meta-analyses have shown that wearing orthokeratology lenses or soft multifocal contact lenses can reduce axial length growth (and hence myopia). However, effects on blinking, ptosis, the function of Meibomian glands, fluorescein and lissamine green staining of the conjunctiva and cornea, production of lid-parallel conjunctival folds and lid wiper epitheliopathy have received less research attention. Contact lens wear produces a subclinical inflammatory response manifested by increases in the number of dendritiform cells in the conjunctiva, cornea and limbus. Papillary conjunctivitis is also a complication of all types of contact lenses. Changes to wear schedule (daily disposable from overnight wear) or lens materials (hydrogel from SiHy) can reduce papillary conjunctivitis, but the effect of such changes on dendritic cell migration needs further study. These changes may be associated with decreased comfort but confirmatory studies are needed. Contact lenses can affect the sensitivity of the ocular surface to mechanical stimulation, but whether these changes affect comfort requires further investigation. In conclusion, there have been changes to lens materials, design and wear schedules over the past 20+ years that have improved their safety and seen the development of lenses that can reduce the myopia development. However, several changes to the ocular surface still occur and warrant further research effort in order to optimise the lens wearing experience.