Diapositiva 1

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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)
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Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee
Effects on the tear film
Biophysical - changes to dynamics and quality
Biochemical - compositional changes
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Biophysical biochemical tear film aspects
Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee

• Biochemistry
• Lipidome
• Proteome
• Mucins, glycocalyx and mucin balls
• Other components

• Cellular content (PMNs)
• Contaminants

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Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee

• 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

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Non-CL gt 10s Rigid CL 2 3 s Hydrogel CL 5 6 s
non-material specific

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

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Interactions with the Tear Film Subcommittee

• Relation of stability to comfort
• With soft CL, discomfort is observed with ?
  TBUT6, 7
• Pre-lens TBUT lt 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

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Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee

• 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
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Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee

• 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

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Interactions with the Tear Film Subcommittee

• Thank you

• TFOS
• Contact Lens Interactions with the Tear Film
  Subcommittee
• Sponsors

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Interactions with the Tear Film Subcommittee

• References
• Collins M, J , Stahmer D, Pearson G. Clinical
  findings associated with incomplete blinking in
  soft lens wearers. Clin Exp Optom 19897255-56.
• 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 2008495319-5324.
• 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 201152 8811-8817.
• Guillon JP, Guillon M. Tear film examination of
  the contact lens patient. Contax 198814-20.
• Chui WS, Cho P, Brown B. Soft contact lens wear
  in Hong Kong-Chinese predicting success.
  Ophthalmic Physiol Opt 200020480-486.
• Fonn D, Dumbleton K. Dryness and discomfort with
  silicone hydrogel contact lenses. Eye Contact
  Lens 200329S101-104
• Glasson MJ, Hseuh S, Willcox MD. Preliminary tear
  film measurements of tolerant and non-tolerant
  contact lens wearers. Clin Exp Optom
  199982177-181.
• Hom MM, Bruce AS. Prelens tear stability
  relationship to symptoms of dryness. Optometry
  200980181-184.

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Interactions with the Tear Film Subcommittee

• 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 2004452563-2568.
• 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
  2003445116-5124.
• 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
  2010511988-1993.
• 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
  2012E-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
  2011522175-2180.
• 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
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• Stahl U, Willcox M, Naduvilath T, Stapleton F.
  Influence of tearfilm and contact lens osmolality
  on comfort in CL wear. Optom Vis Sci
  200986857-867.

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Interactions with the Tear Film Subcommittee

• References
• Stahl U, Willcox M, Naduvilath T, Stapleton F.
  Influence of tearfilm and contact lens osmolality
  on comfort in CL wear. Optom Vis Sci
  200986857-867.
• Evans KS, North RV, Purslow C. Tear ferning in
  contact lens wearers. Ophthalmic Physiol Opt
  200929199-204.
• 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 1998236354-358.
• Chen FS, Maurice DM. The pH in the precorneal
  tear film and under a contact lens measured with
  a fluorescent probe. Exp Eye Res 199050251-259.
• McCarey BE, Wilson LA. pH, osmolarity and
  temperature effects on the water content of
  hydrogel contact lenses. Contact Intraocul Lens
  Med J 19828158-167.
• Glasson MJ, Stapleton F, Willcox MD. Lipid,
  lipase and lipocalin differences between tolerant
  and intolerant contact lens wearers. Curr Eye Res
  200225227-235.
• Berry M, Pult H, Purslow C, Murphy PJ. Mucins and
  ocular signs in symptomatic and asymptomatic
  contact lens wear. Optom Vis Sci
  200885E930-938.
• Pisella PJ, Malet F, Lejeune S, et al. Ocular
  surface changes induced by contact lens wear.
  Cornea 200120820-825.
• Berry M, Purslow C, Murphy PJ, Pult H. Contact
  lens materials, mucin fragmentation and relation
  to symptoms. Cornea 201231770-776.