Putting vital stains in context

Abstract

While vital staining remains a cornerstone in the diagnosis of ocular disease and contact lens complications, there are many misconceptions regarding the properties of commonly used dyes by eye‐care practitioners and what is and what is not corneal staining after instillation of sodium fluorescein. Similarly, the proper use and diagnostic utility of rose Bengal and lissamine green B, the other two ophthalmic dyes commonly used for assessing ocular complications, have similarly remained unclear. Due to the limitations of vital stains for definitive diagnosis, concomitant signs and symptoms in addition to a complete patient history are required. Over the past decade, there have been many reports of a type of corneal staining—often referred to as solution‐induced corneal staining (SICS)—that is observed with the use of multipurpose solutions in combination with soft lenses, more specifically silicone hydrogel lenses. Some authors believe that SICS is a sign of lens/solution incompatibility; however, new research shows that SICS may be neither a measure of lens/solution biocompatibility nor ‘true’ corneal staining, as that observed in pathological situations. A large component of SICS may be a benign phenomenon, known as preservative‐associated transient hyperfluorescence (PATH). There is a lack of correlated signs and/or symptoms with SICS/PATH. Several properties of SICS/PATH, such as appearance and duration, differentiate it from pathological corneal staining. This paper reviews the properties of vital stains, their use and limitations in assessment of the ocular surface, the aetiology of corneal staining, characteristics of SICS/PATH that differentiate it from pathological corneal staining and what the SICS/PATH phenomenon means for contact lens‐wearing patients.

Ethnic differences in dry eye symptoms: Effects of corneal staining and length of contact lens wear

“…Estimates of the prevalence of idiopathic staining in non-contact lens wearers vary widely due to differences in subject selection, study methodology and observer training and criteria [39], yet there is some evidence to suggest that the staining we observed more than 24 h after discontinuation may not be simply "normal" staining unrelated to long-term lens wear. Although some estimates of the prevalence of idiopathic staining in non-CL wearers are as high as 79% [40], other studies have reported prevalences ranging from 0% to 19% [41][42][43], compared with the approximately 39% of subjects with corneal staining in the current study.…”

Re: Putting vital stains in context

“…1 His very thorough review covers the aetiology of corneal staining, including the characteristics of solution-induced corneal stain (SICS) and the particular form of SICS known as preservative-associated transient hyperfluorescence (PATH). 1 As detailed by Professor Efron, PATH is a transient form of SICS being a specific designation for sodium fluorescein staining, which results from wearing certain combinations of contact lens types and brands of storage solutions. 1 Typically, it will dissipate within a few hours of lens insertion.…”

“…1 As detailed by Professor Efron, PATH is a transient form of SICS being a specific designation for sodium fluorescein staining, which results from wearing certain combinations of contact lens types and brands of storage solutions. 1 Typically, it will dissipate within a few hours of lens insertion. Professor Efron's conclusion that SICS, such as PATH, may be a benign phenomenon 1 does not help clinicians manage their contact lens patients at aftercare visits.…”

“…1 Typically, it will dissipate within a few hours of lens insertion. Professor Efron's conclusion that SICS, such as PATH, may be a benign phenomenon 1 does not help clinicians manage their contact lens patients at aftercare visits. Even if some or all of any observed staining is PATH and even whether such staining is benign, how can a clinician know which part of the corneal stain observed is not related to PATH?…”

“…Of course, 'notable' stain does not just depend on the area, location and intensity of staining, because other signs such as conjunctival hyperaemia as well as symptoms will often help make the differential diagnosis between notable and acceptable staining. Staining is frequently a symptomless phenomenon as is PATH in particular, 1,5 at least in the short term. There does not appear to have been any examination of the long-term effects of prolonged exposure to day-to-day PATH, making it difficult to assume that it is benign.…”