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Contact Lens Interactions with the Tear Film Subcommittee Report
Contact Lens Interactions with the Tear Film Subcommittee Report
The tear film is crucial to ocular surface health, and a contact lens,
The tear film is crucial to ocular surface health, and a contact lens,
Effects on the tear film
Effects on the tear film
Biophysical & biochemical tear film aspects
Biophysical & biochemical tear film aspects
Tear film dynamics Blink impact on tear film Lipid layer quantity and
Tear film dynamics Blink impact on tear film Lipid layer quantity and
Biochemistry Lipidome Proteome Mucins, glycocalyx and “mucin” balls
Biochemistry Lipidome Proteome Mucins, glycocalyx and “mucin” balls
Blink impact CL –
Blink impact CL –
Evaporation Non-CL: Evaporation
Evaporation Non-CL: Evaporation
Tear film stability Evaluated with TBUT / NIBUT tests or dynamic tests
Tear film stability Evaluated with TBUT / NIBUT tests or dynamic tests
Relation of stability to comfort With soft CL, discomfort is observed
Relation of stability to comfort With soft CL, discomfort is observed
Tear film thickness Normal thickness around 3µm In CL, PLTF around 2µm
Tear film thickness Normal thickness around 3µm In CL, PLTF around 2µm
Tear volume Total volume in non-CL eye around 2 to 4µl11 In CL,
Tear volume Total volume in non-CL eye around 2 to 4µl11 In CL,
Tear Exchange
Tear Exchange
pH ? by 0.27 – 0.53 units in CL wear19 but is not clearly related to
pH ? by 0.27 – 0.53 units in CL wear19 but is not clearly related to
Changes in tear biochemistry Lipidome:
Changes in tear biochemistry Lipidome:
Summary CLs induce:
Summary CLs induce:
Conclusions absence of a consistent definition has hindered the
Conclusions absence of a consistent definition has hindered the
Future directions to define the biophysical and biochemical properties
Future directions to define the biophysical and biochemical properties
Thank you
Thank you
References Collins M, J , Stahmer D, Pearson G. Clinical findings
References Collins M, J , Stahmer D, Pearson G. Clinical findings
References Maruyama K, Yokoi N, Takamata A, Kinoshita S. Effect of
References Maruyama K, Yokoi N, Takamata A, Kinoshita S. Effect of
References Stahl U, Willcox M, Naduvilath T, Stapleton F. Influence of
References Stahl U, Willcox M, Naduvilath T, Stapleton F. Influence of

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Contact Lens Interactions with the Tear Film Subcommittee Repoе

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1 Contact Lens Interactions with the Tear Film Subcommittee Report

Contact Lens Interactions with the Tear Film Subcommittee Report

Members: Jennifer Craig (Chair & SC Liason) Mark Willcox (Workshop Vice-Chair) Pablo Argueso Cecile Maissa Ulrike Stahl Alan Tomlinson Jianhua Wang Norihiko Yokoi Fiona Stapleton (Harmonization Subcommittee Member)

2 The tear film is crucial to ocular surface health, and a contact lens,

The tear film is crucial to ocular surface health, and a contact lens,

by its very presence, affects the tear film, and therefore has the potential to affect comfort

Interactions with the Tear Film Subcommittee

3 Effects on the tear film

Effects on the tear film

Biophysical - changes to dynamics and quality

Biochemical - compositional changes

Interactions with the Tear Film Subcommittee

4 Biophysical & biochemical tear film aspects

Biophysical & biochemical tear film aspects

Comprehensive review of the literature on each topic with respect to: the pre-corneal (non-CL) tear film the tear film in the presence of a CL the impact of that aspect on discomfort in CL wear Evaluation of deficiencies in the current literature, together with suggestions for future research

Interactions with the Tear Film Subcommittee

5 Tear film dynamics Blink impact on tear film Lipid layer quantity and

Tear film dynamics Blink impact on tear film Lipid layer quantity and

quality Evaporation Stability Temperature Thickness Turn over Volume / CL edge profile Exchange (post-lens)

Tear film quality Osmolality Ferning

pH Viscosity

Interactions with the Tear Film Subcommittee

6 Biochemistry Lipidome Proteome Mucins, glycocalyx and “mucin” balls

Biochemistry Lipidome Proteome Mucins, glycocalyx and “mucin” balls

Other components

Cellular content (PMNs) Contaminants

Interactions with the Tear Film Subcommittee

7 Blink impact CL –

Blink impact CL –

blink frequency to compensate for ? TBUT Incomplete blinks in hydrogel CL wear linked to: increased fluorescein staining discomfort and increased lens deposition1

Lipid layer (LL) Lipid layer ? ? surface tension and ? evaporation In CL wear, LL thickness and uniformity are ? due to ? aqueous layer thickness2 No clear relationship with comfort

Interactions with the Tear Film Subcommittee

8 Evaporation Non-CL: Evaporation

Evaporation Non-CL: Evaporation

with incomplete lipid layer CL ? ? evaporation (x 1.2 – x 2.6) associated with ? stability, independent of lens material Under adverse conditions, ? evaporation related to discomfort in hydrogel, but not SiHy, CL wearers3

Temperature Surrogate measure for tear film evaporation and/or stability No clear relation with comfort

Interactions with the Tear Film Subcommittee

9 Tear film stability Evaluated with TBUT / NIBUT tests or dynamic tests

Tear film stability Evaluated with TBUT / NIBUT tests or dynamic tests

Lipid thickness closely associated with TBUT, thus, in CL: ? Aqueous ? ? lipid layer spread ? ? TBUT

4

Pre-corneal TBUT ? initially but longer term changes in post-removal TBUT* not observed5

Non-CL > 10s

Rigid CL 2 – 3 s

Hydrogel CL* 5 – 6 s

Interactions with the Tear Film Subcommittee

*non-material specific

10 Relation of stability to comfort With soft CL, discomfort is observed

Relation of stability to comfort With soft CL, discomfort is observed

with ? TBUT6, 7 Pre-lens TBUT < 3 s predicts symptomatic CL wear8 With CL, under adverse environmental conditions: ? relative humidity ? ? stability ? ? symptoms9 Wearers unable to tolerate 6 hrs CL wear have lower NIBUT than tolerant wearers (13s vs 20s)10

Interactions with the Tear Film Subcommittee

11 Tear film thickness Normal thickness around 3µm In CL, PLTF around 2µm

Tear film thickness Normal thickness around 3µm In CL, PLTF around 2µm

on stabilisation11 PoLTF approximately 1 – 3µm11 No established association with discomfort

Tear turnover rate No consistent change in TTR with CL wear However, immediately post lens removal, TTR in symptomatic individuals is less than that in asymptomatic individuals12

Interactions with the Tear Film Subcommittee

12 Tear volume Total volume in non-CL eye around 2 to 4µl11 In CL,

Tear volume Total volume in non-CL eye around 2 to 4µl11 In CL,

meniscus volume ? from around 1.5 to 1.0µl11 Limited but significant effect of tear volume on comfort10, 13

Meniscus profile Altered in soft CL wear13 No association with CL discomfort established

Interactions with the Tear Film Subcommittee

13 Tear Exchange

Tear Exchange

with ? lens size,14 but not linked with discomfort Osmolarity No consistent effect of adapted CL wear on osmolarity15 Relation to discomfort equivocal15, 16 Ferning Ferning grade increases with CL wear17 Can differentiate CL and non-CL wearers, but ability to predict intolerance not currently confirmed17, 18

Interactions with the Tear Film Subcommittee

14 pH ? by 0.27 – 0.53 units in CL wear19 but is not clearly related to

pH ? by 0.27 – 0.53 units in CL wear19 but is not clearly related to

comfort20 Viscosity effects of CL unknown Surface tension no studies specific to CL wear some biochemistry changes (lipids, sPLA2, lipocalin) may relate to changes to surface tension21

Interactions with the Tear Film Subcommittee

15 Changes in tear biochemistry Lipidome:

Changes in tear biochemistry Lipidome:

phospholipid levels (due to ? sPLA2)21 is conceivably a contributing factor in CL discomfort Proteome: Most major proteins unaffected by CL wear Possible increases in cytokines ? lipocalin-1 in CL intolerance21 Mucins: Relation to tolerance inconclusive22, 23 Possible relation between pattern of mucin degradation and CL discomfort24

Interactions with the Tear Film Subcommittee

16 Summary CLs induce:

Summary CLs induce:

stability, lipid layer and volume ? evaporation rate To date, the effect on comfort of many of these biophysical properties is unknown or inconclusive

Link to discomfort ?

Link to discomfort ?

stability

lipid layer thickness

evaporation

surface tension

tear turnover

osmolarity

volume

pH

ferning

temperature

Interactions with the Tear Film Subcommittee

17 Conclusions absence of a consistent definition has hindered the

Conclusions absence of a consistent definition has hindered the

correlation of biophysical and biochemical tear film parameters with discomfort the close relationship that exists between tear film stability, ocular surface temperature, and tear evaporation suggests that interventions that modify one aspect will influence all consideration of tear type important in relating tear film biochemistry to discomfort

Interactions with the Tear Film Subcommittee

18 Future directions to define the biophysical and biochemical properties

Future directions to define the biophysical and biochemical properties

inherent to the structural integrity of the normal non-CL tear film to develop lens materials, designs and surfaces that promote biocompatibility … and refine the wetting agents within CL care solutions for long-term wettability of the CL surface … … to a level that allows the tear film to remain stable over the CL surface and support an adequate lipid layer

Interactions with the Tear Film Subcommittee

19 Thank you

Thank you

TFOS Contact Lens Interactions with the Tear Film Subcommittee Sponsors

Interactions with the Tear Film Subcommittee

20 References Collins M, J , Stahmer D, Pearson G. Clinical findings

References Collins M, J , Stahmer D, Pearson G. Clinical findings

associated with incomplete blinking in soft lens wearers. Clin Exp Optom 1989;72:55-56. Yokoi N, Yamada H, Mizukusa Y, et al. Rheology of tear film lipid layer spread in normal and aqueous tear-deficient dry eyes. Invest Ophthalmol Vis Sci 2008;49:5319-5324. Kojima T, Matsumoto Y, Ibrahim OM, et al. Effect of controlled adverse chamber environment exposure on tear functions in silicon hydrogel and hydrogel soft contact lens wearers. Invest Ophthalmol Vis Sci 2011;52: 8811-8817. Guillon JP, Guillon M. Tear film examination of the contact lens patient. Contax 1988;14-20. Chui WS, Cho P, Brown B. Soft contact lens wear in Hong Kong-Chinese: predicting success. Ophthalmic Physiol Opt 2000;20:480-486. Fonn D, Dumbleton K. Dryness and discomfort with silicone hydrogel contact lenses. Eye Contact Lens 2003;29:S101-104 Glasson MJ, Hseuh S, Willcox MD. Preliminary tear film measurements of tolerant and non-tolerant contact lens wearers. Clin Exp Optom 1999;82:177-181. Hom MM, Bruce AS. Prelens tear stability: relationship to symptoms of dryness. Optometry 2009;80:181-184.

Interactions with the Tear Film Subcommittee

21 References Maruyama K, Yokoi N, Takamata A, Kinoshita S. Effect of

References Maruyama K, Yokoi N, Takamata A, Kinoshita S. Effect of

environmental conditions on tear dynamics in soft contact lens wearers. Invest Ophthalmol Vis Sci 2004;45:2563-2568. Glasson MJ, Stapleton F, Keay L, Sweeney D, Willcox MD. Differences in clinical parameters and tear film of tolerant and intolerant contact lens wearers. Invest Ophthalmol Vis Sci 2003;44:5116-5124. Chen Q, Wang J, Tao A, Shen M, Jiao S, Lu F. Ultrahigh-resolution measurement by optical coherence tomography of dynamic tear film changes on contact lenses. Invest Ophthalmol Vis Sci 2010;51:1988-1993. Tomlinson A, Fagehi R, Manahilov V. Why do some contact lens wearers avoid contact lens dry eye symptoms? , 90th Annual Meeting of the American Academy of Optometry. Phoenix, AZ, USA; 2012:E-abstract 120286 Chen Q, Wang J, Shen M, et al. Tear menisci and ocular discomfort during daily contact lens wear in symptomatic wearers. Invest Ophthalmol Vis Sci 2011;52:2175-2180. McNamara NA, Polse KA, Brand RJ, Graham AD, Chan JS, McKenney CD. Tear mixing under a soft contact lens: effects of lens diameter. Am J Ophthalmol 1999;127:659-665. Stahl U, Willcox M, Naduvilath T, Stapleton F. Influence of tearfilm and contact lens osmolality on comfort in CL wear. Optom Vis Sci 2009;86:857-867.

Interactions with the Tear Film Subcommittee

22 References Stahl U, Willcox M, Naduvilath T, Stapleton F. Influence of

References Stahl U, Willcox M, Naduvilath T, Stapleton F. Influence of

tearfilm and contact lens osmolality on comfort in CL wear. Optom Vis Sci 2009;86:857-867. Evans KS, North RV, Purslow C. Tear ferning in contact lens wearers. Ophthalmic Physiol Opt 2009;29:199-204. Ravazzoni L, Ghini C, Macri A, Rolando M. Forecasting of hydrophilic contact lens tolerance by means of tear ferning test. Graefes Arch Clin Exp Ophthalmol 1998;236:354-358. Chen FS, Maurice DM. The pH in the precorneal tear film and under a contact lens measured with a fluorescent probe. Exp Eye Res 1990;50:251-259. McCarey BE, Wilson LA. pH, osmolarity and temperature effects on the water content of hydrogel contact lenses. Contact Intraocul Lens Med J 1982;8:158-167. Glasson MJ, Stapleton F, Willcox MD. Lipid, lipase and lipocalin differences between tolerant and intolerant contact lens wearers. Curr Eye Res 2002;25:227-235. Berry M, Pult H, Purslow C, Murphy PJ. Mucins and ocular signs in symptomatic and asymptomatic contact lens wear. Optom Vis Sci 2008;85:E930-938. Pisella PJ, Malet F, Lejeune S, et al. Ocular surface changes induced by contact lens wear. Cornea 2001;20:820-825. Berry M, Purslow C, Murphy PJ, Pult H. Contact lens materials, mucin fragmentation and relation to symptoms. Cornea 2012;31:770-776.

Interactions with the Tear Film Subcommittee

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