Biomedical science, anterior segment diseases and advanced
Transcription
Biomedical science, anterior segment diseases and advanced
Biomedical science, anterior segment diseases and advanced contact lenses M i c h a e l W y s s & M i c h a e l Bärtschi M.Sc.Optom. et M.Med.Educ., FAAO kontaktlinsenstudio baertschi, Bern / Switzerland Adjunct faculty New England College of Optometry, Boston/USA Schedule 1st Day Saturday: Modul 1 (5 lecture hours) 2nd Day Sunday : Modul 2, A & B, 3 (5,5 lecture hours incl. 2 x 1,5 hours workshop) 3rd Day Monday : Modul 3 & C, 4 (6 lecture hours incl. 1,5 hours workshop) 4th Day Tuesday: Modul 4, 5, 6 (7,0 lecture hours) 5th Day Wednesday: Modul 6, 7 (5,5 lecture hours) incl. final discussion 5. Orthokeratology and Myopia Control • Modern Orthokeratology lens design and history of OK • Orthokeratology theory and research, Myopia control • Patient selection and fitting • Results, complications and complication management in OK Duration 4 hours 6. Contact lenses for Infants and Children's • List all ametropic conditions of babies, toddlers and children • Understand the different approach to serve babies and toddlers • Differentiate the visual tests • Understand the specific visual needs of babies, toddlers and children • Describe the fitting procedures of RGP lenses on children • Identify the need for multi focal RGP contact lenses • Get news ideas and perspectives Duration 3 hours A day in the eye hospital University Eye Hospital Basel, Switzerland A day in the eye hospital Experience the extraordinary ! A day in the eye hospital From babies to old men A day in the eye hospital From beautiful to ugly A day in the eye hospital Most of the time very vibrant ! Introduction General statements of Optician, Optometrists and Ophthalmologists (in Europe) : - Children can‘t bear contact lenses ! - Children do loose their contact lenses constantly ! - On a growing eye you can’t fit a contact lens ! - As long as the child can’t pay for his lenses himself, it is not allowed to wear contact lenses ! Target group 1 Approx. 20-40 % of the European School children are ametropic. Approx. 50 % of the European-Teenagers are ametropic. 100 % of all of them need a excellent optical and social solution. Source : MedLine/PubMed (Sweden, UK, Spain, USA) About 1,44 Mio Children per year in Germany, Austria and Switzerland Target groups Astigmatism Hypermetropia Myopia Anisometropia Aphakia Children and eye glasses Children loves eye glasses ! (Hyperopia +8,0 dpt) At least their parent believe and unfortunately some optometrists ! Children and eye glasses Children loves contact lenses ! (Hyperopia +8,0 dpt) This is what the children believes and their contact lens specialists ! Target group Aphakia 0,03 % of the new born do need cataract surgery during the first five weeks of their live. (Intracapsular lens extraction) 0,01 % of the children do need Cataract surgery due to systemic or traumatic reasons 100 % of all of them need a excellent optical and social solution. Source : MedLine/PubMed (Spain, Sweden, UK, USA) About 29‘000 per year in US/Canada und Europe Methods Traditional optical aid : - Eye glasses (SV, Bifocal, Multifocal) - Contact lenses (SV) - Contact lenses (SV) and reading glasses - IOL and contact lenses or eye glasses - Multifocal IOL (effective reading power/Add less than commercially described) - LASIK / LASEK ? - Orthokeratologie ? Methods You have to see thru children's eyes to fit contact lenses for children Myopia (approx. -1,5 dpt) Visual image with myopia Anisometropia (approx. -1,5 dpt) Methods of investigation Autorefraktometer and –keratometer (e.g. Retinamax) Topography and Slit lamp Retinascope and Ophthalmoscope Methods of investigation Dynamic close distance retinascopy (Mohindra) Image is an Illustration : Correct would be monocular and in a dark room ! Methods of investigation Preferential Looking Test (Babies from 2-3 months) Methods of investigation Preferential Looking Test Visual evoked cortical potentials VECP Methods of investigation Teller Cards (A.Young 1997) Babies from 2-3 months Cardiff Cards (Infants of 1-3 years) Methods of investigation Lang-Stereo-Test (Infants of 1-3 years) Glasmarbles or Sugar pearls (Infants of 1-3 years) Methods of investigation Lea Hyvärinen Test Children from 3 years Methods of investigation Landolt rings und Snellen signs from approx. 5 years Numbers and letters from approx. 6 - 8 years Methods of investigation Vision Contrast Test (VCT) und Functional Acuity Contrast Test (FACT) (from approx. 6 - 8 jährig) Methods of investigation Ophthalmoscope as „Hand held magnifier with illumination“ (up to 5x magnification) Methods of investigation Blue light LED Hand held magnifier with yellow filter and 2,5 x Magnification Methods of investigation Blue light LED Hand held magnifier with yellow filter and 2,5 x Magnification Table of estimation Age CL radii n.E. 1. Month 6.80 - 7.00 mm 0.0 – 0.3 6. Months 7.00 - 7.20 mm 0.0 – 0.3 1 Year 7.20 - 7.40 mm 0.3 – 0.4 2 Years 7.40 - 7.60 mm 0.3 – 0.4 3 Years 7.60 - 7.80 mm 0.3 – 0.4 5 Years 7.60 - 8.00 mm 0.4 – 0.5 8 Years 7.60 - 8.00 mm 0.4 – 0.6 TIP 1. Fit over all diameter OAD as large as possible and as small as necessary. 2. Only use materials with high oxygen permeability (Dk). 3. Fit periphery slightly tighter than for an adult. (n.E. parallel or even – 0,1) 4. Choose large front optic zone according to the juvenile pupil diameter. (> 7mm) TIP Very often oval diameters e.g. 10.0 / 9.2 mm Different colours for the right and the left contact lens. e.g. Blue / Ice Blue TIP Even Teenies do use make-up already excessive and wrong ! Aphakia with CL and Bi-focal glasses Table of estimation (Aphakia) Age Power CL radii Add. reading 1. Month + 35 dpt 6.80 - 7.00 mm + 6.00 dpt 6. Months + 30 dpt 7.00 - 7.20 mm + 5.00 dpt 1 Year + 25 dpt 7.20 - 7.40 mm + 4.00 dpt 2 Years + 23 dpt 7.40 - 7.60 mm + 3.75 dpt 3 Years + 21 dpt 7.60 - 7.80 mm + 3.50 dpt 5 Years + 20 dpt 7.60 - 8.00 mm + 3.25 dpt 8 Years + 18.5 dpt 7.60 - 8.00 mm + 3.00 dpt Text Table not valid in case of Microphthalmus or Megalocornea ! TIP 1. Fit over all diameter OAD as large as possible and as small as necessary. 2. Only use materials with very high oxygen permeability (Dk). 3. Fit periphery slightly tighter than for an adult. (n.E. parallel or even – 0,1) 4. Choose large front optic zone according to the juvenile pupil diameter. (> 7mm) 5. Only use light colours. (white or Ice Blue) 6. Add according the length of the arms ! TIP Jessica, 6 Jahre Francesca 5 Jahre TIP Jessica, 6 Jahre Francesca 5 Jahre Tri-focal RGP on a eye of a 2 years infant Peri- (extra)limbal RGP on an eye of a 14 years old teenager Methode Children are substantially limited due to the use of sub-optimal optical aid: - in their social environment - in their Mobility - in their personal development Source : Roger L. Hyatt,MD : „Rehabilitation of children with Cataracts“ 1998 and Patient questionnaire (University Eye Hospital Basel Summer 2000) Methode Fitting of hyper permeable RGP single vision or multifocal contact lenses for the purpose of ametropia, astigmatism and aphakia correction. RGP contact lenses : - Because of physiological reasons (Bo-XO, Optimum Extreme, Menicon Z) - Because of the tremendous technical possibilities and quality - Because optical or anatomical changes are easy to handle - Because infants and children do tolerate RGP contact lenses well (age depending approx. 80-99%) Myopia Single vision RGP Aphakia with CL and Bi-focal glasses Aphakia with CL and Bi-focal glasses Multifocal RGP Bi-, Multi- oder Trifocal D I N D I N Retina Simultaneous Systems are the preferred lenses for infants or children’s. Multifocal RGP CL RGP und Myopie Progression Scientific studies are contradictory ! If any positive effect, only with RGP lenses and only in the first year of use. Is Ortho-Keratology the new „magic bullet“ ? Image Ortho-K : KL-Studio Bärtschi Image Modula M : D. Wegmann, Galifa Results1 89.6 % of all babies and children, new fit with RGP single vision contact lenses in the last 8 years, successfully wear their lenses daily. (n=96) - 8 children had to be refitted with Silicone-Hydrogel lenses after failed with the RGP fit. - 2 fittings had to discontinue due to refusal and non-compliance. - Most of the children wear their lenses on extended wear mode with cleaning intervals of 1 – 6 weeks - 2 x Conjunctivitis bulbi and 1 x Conjunctivitis tarsi, 0 x Keratitis Infants and children with CL Infants and children with CL Infants and children with CL Lukas, 2 ½ Jahre Results 2 All(*) of the 15 congenital cataract babies, who underwent cataract surgery between 1992 and 2002 were refitted with multi-focal RGP lenses between February 2000 and summer 2005, developed subjective and objective quicker, are smarter and are much more integrated in their social environment than before with their single vision contact lenses and bifocal eye glasses. (n = 15) (Questionnaire University Eye Hospital Basel, Switzerland) (*) 1 Child got an Intraocular lens due to non-compliance after 1 year. „My child is finally as normal as any other child her school class !“ Diskussion1 Not only tolerate children RGP contact lenses well, babies can be fitted as young as a few weeks of life and cause in general less ocular problems than most adults. Diskussion2 Are Silicone-Hydrogels applicable for children ? Definitely YES, as well as spheric or toric lenses ! - Disposable as well as traditional lenses possible. - Important: To assure lens care and exchange rhythm. - Steep BC most useful (Acuvue Oasys 8,4, Acuvue Advance 8,3 or Night & Day 8,4, Air Optix Individual). - After swimming always clean the lenses ! - More often transient ocular problems than with RGP lenses - The children usually just forget that they are wearing contact lenses. Please mind the many technical possibilities. Well established Silicone-Hydrogels Night & Day Pure Vision Acuvue Advance Air Optix Lotrafilcon A Balafilcon A Galyfilcon A Lotrafilcon B Senofilcon A 35 % Ionic 110 47 % Non-ionic 85 33 % Non-ionic 138 38 % Non-ionic 147 Plasma oxidation glassy silicate “islands” No surface coating hydroclear 25nm plasma coating-continuous hydrophilic surface No surface coating hydroclear Base Curve 24 % Non-ionic 175 25nm plasma coatingcontinuous hydrophilic surface 8.4 / 8.6 8.6 8.3 / 8.7 8.6 8.4 / 8.8 Diameter 13.8 14.0 14.0 14.2 14.0 Power -10 to + 6 -12 to +6 -12 to + 8 -10 to + 6 Center thickness (- 3.00D) 0.08 0.09 0.07 0.08 0.07 Visibility tint UV blocking visibility tint Visibility tint UV blocking visibility tint Material Water Content Dk/t Surface Treatment Other April 2008 (MiB) Acuvue Oasys -12 to + 8 Well established Silicone-Hydrogels Biofinity PureVision Toric Acuvue Advance f Astig Comfilcon A Balafilcon A Galyfilcon A Sifilcon A Hygel Dk/t 48 % Non-ionic 160 35 % Ionic 110 47 % Non-ionic 86 32 % Non-ionic 117 54 % Non-ionic 53 Surface Treatment No surface coating Plasma oxidation glassy silicate “islands” No surface coating hydroclear 25nm plasma coating-continuous hydrophilic surface No surface coating, lathing Base Curve 8.6 8.6 8.5 7.4 - 9.2 All Diameter 14.0 All - 12 to + 8 14.5 -12 to + 8 13.2 / 14.0 / 14.8 Power 14.0 -9 to +6 -0.75 bis -2.25 cyl -0.75 bis -2.25 cyl -20 to + 20 All Center thickness (- 3.00D) 0.08 0.10 0.07 0.07 0.10 Visibility tint UV blocking visibility tint Visibility tint UV blocking, clear/visibility tint Material Water Content Other April 2008 (MiB) Visibility tint Air Optix Custom Hygel sph & toric Children are able to communicate Melanie, 8 years old Aphakic girl 7 – years old Aphakic girl 7 – years old Conclusion Keep your perspective, stay cool and never give up ! We wish you great success with contact lenses for our most valuable patients !
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