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Guillon tear film classification system
Appendix B: Guillon tear film classification system
Appendix B Guillon tear film classification system All the pre-ocular and pre-lens tear film patterns depicted in this appendix were imaged and captured photographically
using a tearscope. All tear film lipid patterns should be assessed before any other examination and should be judged 2 seconds after the blink when the upward motion of the tear film (a viscosity characteristic) has stopped.
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B
Appendix B: Guillon tear film classification system
PRE-OCULAR TEAR FILM LIPID PATTERNS Dark eye
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Light eye
Open meshwork (marmorial)
Observed in 21% of the population 13–50 nm thickness Grey appearance of low reflectivity Sparse, open meshwork pattern faintly visible after the blink In the lower thickness range it may not be visible at low magnification Thought to represent a deficient lipid layer
Closed meshwork (marmorial)
Observed in 10% of the population 30–50 nm thickness Grey appearance of average reflectivity More compact meshwork pattern Thought to represent a normal lipid layer
Wave (flow)
Observed in 23% of the population 50–80 nm thickness Pattern of vertical or horizontal grey waves of good visibility between blinks Most common lipid layer
Amorphous
Observed in 24% of the population 80–90 nm thickness Even pattern with whitish highly reflective surface Thought to represent an ideal, well-mixed lipid layer
First-order colour fringes
Observed in 10% of the population 90–140 nm thickness Discrete brown and blue well-spread lipid layer interference fringes superimposed on a whitish background Thought to represent a regular, very full lipid layer
Appendix B: Guillon tear film classification system EXCESSIVE AND CONTAMINATED LIPIDS Second-order colour fringes
Observed in 5% of the population 140–180 nm thickness Discrete green and red tightly packed lipid layer interference fringes superimposed on a whitish background Thought to represent an abnormal lipid layer of increased thickness in the coloured areas
Globular lipid with multiple colours
Observed in 7% of the population >180 nm thickness Highly variable colours, but typically combinations of brown, blue, green and red, irregularly spread Sometimes globules of intense colour appear Thought to represent an extremely heavy and irregular lipid layer, often associated with oversecretion, blepharitis or lipid contamination
Lipid break-up and cosmetics
Abnormal lipid pattern Seen when cosmetic products invade the tear film and break the lipid layer. The area devoid of lipid coverage appears dark grey as the light is reflected specularly from the bare aqueous phase. The area covered by lipid is highly reflective and can be confined to form isolated circular islands
Eye ointments
Abnormal appearance Ointments destroy the normal tear film structure Heavy striated fringes of yellow, brown, blue, green and purple, which are often irregularly distributed, indicating the variable thickness of the ointment
Face cream
Lipid break-up observed when moisturizers or face creams invade and break the lipid layer Coloured fringes on grey background
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B
Appendix B: Guillon tear film classification system
PRE-SOFT LENS TEAR FILM The following sequence of images can be taken to represent an ideal pre-lens tear film going through the process of thinning caused by drainage and evaporation. Initially, the presence of a superficial lipid layer reduces evaporation and the thick aqueous phase ensures the separation of the lipid and mucus phases. Following thinning of the aqueous phase, some lipid components migrate posteriorly and come into contact with the mucus phase and lens surface, which produces non-wetting patches. An alternative interpretation of this sequence of images is that they represent different tear film structures that appear immediately after eye opening. In this case, the images are arranged from ‘best’ to ‘worst’ and can be used to grade the quality of the pre-lens tear film.
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Meshwork lipid coverage
Appearance of a good tear film on the surface of a soft contact lens immediately after eye opening Thin lipid layer present Aqueous layer fringes not visible denote an aqueous phase >3.5 µm thick
Lipid with aqueous fringes
Appearance of tear film on the surface of a soft contact lens 4 seconds after eye opening Very thin lipid layer of low visibility Blue, green, yellow and red aqueous interference fringes faintly visible under the lipid layer Aqueous layer 2–3.5 µm thick
Aqueous fringes
Appearance of tear film on the surface of a soft contact lens 8 seconds after eye opening Lipid layer virtually absent Narrow green and red aqueous interference fringes are easily visible Aqueous layer 2 µm thick
Dry area
Appearance of tear film on the surface of a soft contact lens 12 seconds after eye opening Lipid layer absent Widely spaced, bright green and red aqueous interference fringes visible Aqueous layer <1 µm thick Edge of the mucus layer visible Lens surface visible at the centre of the dry spot
Lipid contamination
Appearance of tear film on the surface of a soft contact lens contaminated with lipid Oval non-wetting patch occurs immediately after eye opening Contaminating lipids highly visible Blue, green, yellow and red interference fringes visible in a thin aqueous phase
Appendix B: Guillon tear film classification system PRE-RIGID LENS TEAR FILM As for the pre-soft lens tear film, the following sequence of images of the pre-rigid lens tear film can be taken to represent either (a) an ideal pre-lens tear film going through the process of thinning, or (b) different tear film structures immediately after eye opening ranked from ‘best’ to ‘worst’. Complete lipid cover
Appearance of an ideal tear film on the surface of a rigid lens immediately after eye opening Seen in only 5% of cases Thin and complete lipid cover Blue, green, yellow and red aqueous layer interference fringes faintly visible
Thick aqueous layer
Appearance of tear film on the surface of a rigid lens 4 seconds after eye opening Very thin lipid layer Narrow aqueous layer interference fringes denote a thick aqueous phase Aqueous layer >2 µm thick
Medium aqueous layer
Appearance of tear film on the surface of a rigid lens 8 seconds after eye opening Lipid layer absent Well-defined aqueous layer interference fringes Thinning of aqueous phases superiorly may be induced by the upper tear meniscus Aqueous layer 1–2 µm thick
Thin aqueous layer
Appearance of tear film on the surface of a rigid lens 12 seconds after eye opening Lipid layer absent Broad, bright red and green aqueous layer interference fringes Aqueous layer <1 µm thick
Drying
Appearance of tear film on the surface of a rigid lens 16 seconds after eye opening Lipid layer absent Irregular broad, bright red and green aqueous layer interference fringes visible, some in a circular pattern, formed by the evaporating tear film Aqueous layer <0.5 µm thick inferiorly and absent superiorly
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Appendix B Guillon tear film classification system All the pre-ocular and pre-lens tear film patterns depicted in this appendix were imaged and captured photographically
using a tearscope. All tear film lipid patterns should be assessed before any other examination and should be judged 2 seconds after the blink when the upward motion of the tear film (a viscosity characteristic) has stopped.
307
B
Appendix B: Guillon tear film classification system
PRE-OCULAR TEAR FILM LIPID PATTERNS Dark eye
308
Light eye
Open meshwork (marmorial)
Observed in 21% of the population 13–50 nm thickness Grey appearance of low reflectivity Sparse, open meshwork pattern faintly visible after the blink In the lower thickness range it may not be visible at low magnification Thought to represent a deficient lipid layer
Closed meshwork (marmorial)
Observed in 10% of the population 30–50 nm thickness Grey appearance of average reflectivity More compact meshwork pattern Thought to represent a normal lipid layer
Wave (flow)
Observed in 23% of the population 50–80 nm thickness Pattern of vertical or horizontal grey waves of good visibility between blinks Most common lipid layer
Amorphous
Observed in 24% of the population 80–90 nm thickness Even pattern with whitish highly reflective surface Thought to represent an ideal, well-mixed lipid layer
First-order colour fringes
Observed in 10% of the population 90–140 nm thickness Discrete brown and blue well-spread lipid layer interference fringes superimposed on a whitish background Thought to represent a regular, very full lipid layer
Appendix B: Guillon tear film classification system EXCESSIVE AND CONTAMINATED LIPIDS Second-order colour fringes
Observed in 5% of the population 140–180 nm thickness Discrete green and red tightly packed lipid layer interference fringes superimposed on a whitish background Thought to represent an abnormal lipid layer of increased thickness in the coloured areas
Globular lipid with multiple colours
Observed in 7% of the population >180 nm thickness Highly variable colours, but typically combinations of brown, blue, green and red, irregularly spread Sometimes globules of intense colour appear Thought to represent an extremely heavy and irregular lipid layer, often associated with oversecretion, blepharitis or lipid contamination
Lipid break-up and cosmetics
Abnormal lipid pattern Seen when cosmetic products invade the tear film and break the lipid layer. The area devoid of lipid coverage appears dark grey as the light is reflected specularly from the bare aqueous phase. The area covered by lipid is highly reflective and can be confined to form isolated circular islands
Eye ointments
Abnormal appearance Ointments destroy the normal tear film structure Heavy striated fringes of yellow, brown, blue, green and purple, which are often irregularly distributed, indicating the variable thickness of the ointment
Face cream
Lipid break-up observed when moisturizers or face creams invade and break the lipid layer Coloured fringes on grey background
309
B
Appendix B: Guillon tear film classification system
PRE-SOFT LENS TEAR FILM The following sequence of images can be taken to represent an ideal pre-lens tear film going through the process of thinning caused by drainage and evaporation. Initially, the presence of a superficial lipid layer reduces evaporation and the thick aqueous phase ensures the separation of the lipid and mucus phases. Following thinning of the aqueous phase, some lipid components migrate posteriorly and come into contact with the mucus phase and lens surface, which produces non-wetting patches. An alternative interpretation of this sequence of images is that they represent different tear film structures that appear immediately after eye opening. In this case, the images are arranged from ‘best’ to ‘worst’ and can be used to grade the quality of the pre-lens tear film.
310
Meshwork lipid coverage
Appearance of a good tear film on the surface of a soft contact lens immediately after eye opening Thin lipid layer present Aqueous layer fringes not visible denote an aqueous phase >3.5 µm thick
Lipid with aqueous fringes
Appearance of tear film on the surface of a soft contact lens 4 seconds after eye opening Very thin lipid layer of low visibility Blue, green, yellow and red aqueous interference fringes faintly visible under the lipid layer Aqueous layer 2–3.5 µm thick
Aqueous fringes
Appearance of tear film on the surface of a soft contact lens 8 seconds after eye opening Lipid layer virtually absent Narrow green and red aqueous interference fringes are easily visible Aqueous layer 2 µm thick
Dry area
Appearance of tear film on the surface of a soft contact lens 12 seconds after eye opening Lipid layer absent Widely spaced, bright green and red aqueous interference fringes visible Aqueous layer <1 µm thick Edge of the mucus layer visible Lens surface visible at the centre of the dry spot
Lipid contamination
Appearance of tear film on the surface of a soft contact lens contaminated with lipid Oval non-wetting patch occurs immediately after eye opening Contaminating lipids highly visible Blue, green, yellow and red interference fringes visible in a thin aqueous phase
Appendix B: Guillon tear film classification system PRE-RIGID LENS TEAR FILM As for the pre-soft lens tear film, the following sequence of images of the pre-rigid lens tear film can be taken to represent either (a) an ideal pre-lens tear film going through the process of thinning, or (b) different tear film structures immediately after eye opening ranked from ‘best’ to ‘worst’. Complete lipid cover
Appearance of an ideal tear film on the surface of a rigid lens immediately after eye opening Seen in only 5% of cases Thin and complete lipid cover Blue, green, yellow and red aqueous layer interference fringes faintly visible
Thick aqueous layer
Appearance of tear film on the surface of a rigid lens 4 seconds after eye opening Very thin lipid layer Narrow aqueous layer interference fringes denote a thick aqueous phase Aqueous layer >2 µm thick
Medium aqueous layer
Appearance of tear film on the surface of a rigid lens 8 seconds after eye opening Lipid layer absent Well-defined aqueous layer interference fringes Thinning of aqueous phases superiorly may be induced by the upper tear meniscus Aqueous layer 1–2 µm thick
Thin aqueous layer
Appearance of tear film on the surface of a rigid lens 12 seconds after eye opening Lipid layer absent Broad, bright red and green aqueous layer interference fringes Aqueous layer <1 µm thick
Drying
Appearance of tear film on the surface of a rigid lens 16 seconds after eye opening Lipid layer absent Irregular broad, bright red and green aqueous layer interference fringes visible, some in a circular pattern, formed by the evaporating tear film Aqueous layer <0.5 µm thick inferiorly and absent superiorly
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