This document discusses contact lens characteristics and oxygen transmission. It covers corneal oxygen requirements for daily wear and extended wear lenses. Higher oxygen transmissibility (Dk/t) is required for extended wear to prevent corneal swelling. The document also discusses factors that influence gas permeability and oxygen transport, including lens material, water content, thickness, and deposits. Silicone-based materials have higher oxygen permeability than other materials. Thinner lenses and those with higher water content provide greater oxygen transmissibility.
Advance research & development in contact lens by jasmin (Raees Optom)modi Jasmin Modi
Here latest research study of contact lens it includes material, manufacturing ,Case study , Contact lens future , contact lens practice in coivid 19 guidelines & many more interesting stuff.
it's also available on youtube you can check it here
https://www.youtube.com/watch?v=_EuJYDMliGI
Advance research & development in contact lens by jasmin (Raees Optom)modi Jasmin Modi
Here latest research study of contact lens it includes material, manufacturing ,Case study , Contact lens future , contact lens practice in coivid 19 guidelines & many more interesting stuff.
it's also available on youtube you can check it here
https://www.youtube.com/watch?v=_EuJYDMliGI
Development of Multi-functional Coatings(Anti-Reflective and Anti-Fogging)HasanAhmed139
Multifunctional nano-coatings with distinctive optical properties and super-wettability are extremely enthralling due to their wide array of applications. In our work, sequential dip-coatings have been applied, to glass slides, so as to develop anti-fog coating with high transmittance values of around 95%. Although the numbers are highly commendable; however, special care and variable coats are necessary with the intention to achieve the objective. Keeping this in mind, the first coating of single layer applied directly on glass slide, is that of Acid Catalyzed Silica Sol (ACSS) which serves the purpose of a binding layer between the glass slide and the successive coatings. Following that, three layers of small Solid Silica Nano-particles (SSNs) are applied subsequently over ACSS in order to provide the desired transmittance. Thereafter, a three layer coating of Dendrimer-like Mesoporous Silica Nano-particles (DMSNs) is applied over SSNs; to obtain a super-hydrophilic surface that serves as a highly wettable surface in specific and an anti-fog coating in general. The ratio 1: 3: 3, for coatings of ACSS, SSNs and DMSNs, was nominated as an optimal match for the predominant multifunctionality of the coating and any slight change in the ratio brought about a huge divergence in the corresponding character of the coating.
There are over 1,000 nanomaterial-containing products being industrially manufactured with still more under development by academic researchers and small start-up companies. Nanomaterials have physical and chemical properties that are often different from their parent material, making them desirable for certain product applications. While the novelty and applications of engineered nanomaterials are well-understood, the understanding of their inherent toxicities and potential workplace and environmental impact is in its infancy.
Contact Lenses Management in PediatricsKaylie Ling
The post-surgical management of the pediatric aphakic is important. Contact lens is the best optical device in the post-operative aphakia to provide good visual quality.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
Follow us on: Pinterest
Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Development of Multi-functional Coatings(Anti-Reflective and Anti-Fogging)HasanAhmed139
Multifunctional nano-coatings with distinctive optical properties and super-wettability are extremely enthralling due to their wide array of applications. In our work, sequential dip-coatings have been applied, to glass slides, so as to develop anti-fog coating with high transmittance values of around 95%. Although the numbers are highly commendable; however, special care and variable coats are necessary with the intention to achieve the objective. Keeping this in mind, the first coating of single layer applied directly on glass slide, is that of Acid Catalyzed Silica Sol (ACSS) which serves the purpose of a binding layer between the glass slide and the successive coatings. Following that, three layers of small Solid Silica Nano-particles (SSNs) are applied subsequently over ACSS in order to provide the desired transmittance. Thereafter, a three layer coating of Dendrimer-like Mesoporous Silica Nano-particles (DMSNs) is applied over SSNs; to obtain a super-hydrophilic surface that serves as a highly wettable surface in specific and an anti-fog coating in general. The ratio 1: 3: 3, for coatings of ACSS, SSNs and DMSNs, was nominated as an optimal match for the predominant multifunctionality of the coating and any slight change in the ratio brought about a huge divergence in the corresponding character of the coating.
There are over 1,000 nanomaterial-containing products being industrially manufactured with still more under development by academic researchers and small start-up companies. Nanomaterials have physical and chemical properties that are often different from their parent material, making them desirable for certain product applications. While the novelty and applications of engineered nanomaterials are well-understood, the understanding of their inherent toxicities and potential workplace and environmental impact is in its infancy.
Contact Lenses Management in PediatricsKaylie Ling
The post-surgical management of the pediatric aphakic is important. Contact lens is the best optical device in the post-operative aphakia to provide good visual quality.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
Follow us on: Pinterest
Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
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Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
2. The IACLE Contact Lens Course (all formats) is the sole property of the International
Association of Contact Lens Educators (IACLE) and is protected, without limitations, by
copyright. By accessing this material, you agree to the following terms and conditions:
You may only access and use the IACLE Contact Lens Course for personal or
educational purposes. Any dissemination or sale of the IACLE Contact Lens Course,
either in whole or in part, or use of the materials for other than educational and personal
purposes, is strictly prohibited without the express written consent of IACLE. Except as
declared below, you may not reproduce, republish, post, transmit, or distribute any
material included in the IACLE Contact Lens Course.
You may print materials for personal or educational purposes only. All copyright
information, including the IACLE logo, must remain on the material. Appropriate
reference must be provided to any use of the content of the IACLE Contact Lens Course,
including text, images, &/or illustrations.
COPYRIGHT NOTICE
3. SPONSORS
Development and delivery of contact lens education by IACLE is supported
through educational grants and in-kind contributions
Major In-Kind
Supporters
Industry
Supporters
4. Published in Australia by
The International Association of Contact Lens Educators
First Edition 1997
The International Association of Contact Lens Educators 1996
All rights reserved. No part of this publication may be reproduced, stored in a
retrieval system, or transmitted, in any form or by any means, without the prior
permission, in writing, of:
The International Association of Contact Lens Educators
IACLE Secretariat,
PO Box 656
Kensington NSW 1465
Australia
Email: iacle@iacle.org
5. The IACLE Curriculum Project is the result of a desire to raise
the general standard of eyecare education, to make contact
lens wear safer and more successful, and to develop the
contact lens business further by creating the educational
infrastructure that will produce the teachers, students, and
practitioners of the future.
Full acknowledgements, along with the educator’s guide to the
IACLE Contact Lens Course (ICLC), can be found on the
IACLE website at www.iacle.org
ACKNOWLEDGEMENTS
13. 0
10
20
0 10 20 30 40
Dk/tavg (cm x ml O2) / (sec x ml x mm Hg)
Corneal
Swelling
(%)
Dk/tavg = 87 x 10-9
15
5
140
130
//
Holden and Mertz, 1984
OVERNIGHT OEDEMA vs Dk/t
EXTENDED WEAR
14. DYNAMIC OXYGEN SUPPLY
• Post-lens tear film exchange rates:
–SCL 1% per blink
–RGP 15 - 20% per blink
• Blinking
–rate
–quality (completeness)
• RGP vs SCL fitting characteristics
15. GAS MOVEMENT THROUGH LENSES
• Composition of polymer
• Temperature effect
• Partial pressure of gas at lens surface
• Lens thickness
• Boundary layer effect
19. GAS SOLUBILITY
• Absorption process of a gas within
the material
• Similar to a sponge which absorbs
and holds water
• Gas is dissolved, or solubilized,
into the material
20. RGP PERMEABILITY
• Siloxane bonds (Si-O-Si) provide
molecular sized 'voids'
• Size, rotation and flexibility of
bonds affect permeability
• Concentration gradient
21. RGP MATERIALS
SILOXANE COMPONENT
• Methyl groups small
• Methyl groups non-polar,
therefore more mobile
• Distance between Si atoms is
large
• Large polymer-free space
• Polymer backbone is highly
elastic (extensible)
Backbone
Compressed
Relaxed
Extended
O
CH3
Si
CH3
O
O
130°
Extensible
backbone
CH3
Si
CH3
Si
Methyl groups
can rotate
freely about
Si atom
22. RGP PERMEABILITY
Three step process:
• Gas dissolves into the anterior lens surface
• Diffusion through the lens proper
• Gas leaves via the posterior lens surface
and dissolves into the post-lens tear film
23. RGP PERMEABILITY
• Permeability is a function of molecular
motion and/or solubility
• Permeability increased by:
–improved surface characteristics
–higher temperatures
–decreased cross-linking
–greater atmospheric pressure
• Polymers involve compromises
25. RGP PERMEABILITY
• Siloxane is much more permeable
than flourine
• Fluorinated polymers have
superior surface characteristics
• Fluorine increases solubility of
oxygen in the material
FLUORINATED MATERIALS
26. RGP CONTACT LENSES
OXYGEN SUPPLY
• Material permeability
• Effect of deposits is minimal
• Lens thickness/BVP
• Tear exchange per blink
• Tear layer thickness under lens
27. SCL PERMEABILITY
• Gas flow through the water phase
(not polymer)
• Range of water contents
• Water properties within the polymer
–bound (non-freezing water)
–free (freezing water)
28. WATER CONTENT
WATER DIPOLE
CH3
H2C = C
C
CH2
CH2
O
H
O
O
Water dipole
O
H
H
+ +
–
–
+
O
H
H
+ +
–
O
H
H
+
+
–
Hydroxyl ‘tail’
HEMA monomer
O
H
–
+
Water dipoles at the
hydroxyl ‘tail’
Hydrogen bond
O
H
H
+ +
–
Bound water
Free water
30. SCL PERMEABILITY
• Only free water is available for O2 transport
• Ratio of bound to free water is influential
• New polymers (siloxane components)
• Effect of tints
–opaque
–dyes
31. NOVEL SCL POLYMER
• Biphasic block-copolymer
• Siloxane-based polymeric phase
• Coupled with a water phase
• O2 permeability increases as H2O
content decreases
36. CORNEAL SWELLING
Material (8 hrs wear) Swelling (%)
Low Water 12
Mid Water 10
High Water 11
Novel Polymer 4
Siloxane Elastomer 2.5
SCL OVERNIGHT WEAR
La Hood, CCLRU Data
37. CORNEAL SWELLING
Material (8 hrs wear) Swelling (%)
PMMA 6
Low Dk 3 - 4
Mod Dk 1
High Dk 0
RGP DAILY WEAR
La Hood, CCLRU Data
38. CORNEAL SWELLING
Material (8 hrs wear) Swelling (%)
Low Dk 10-13
Mod Dk 7-9
High Dk 5-6
RGP OVERNIGHT WEAR
La Hood, CCLRU Data
39. SILOXANE ELASTOMER
• A dimethyl polysiloxane polymer
• Inherently hydrophobic
• Pure polymer very oxygen permeable
• Permeability of the ‘filled’ polymer used
is significantly lower
40. SILOXANE ELASTOMER
• Less overnight swelling than no lens
2.0% vs 3.6%
• Possible reasons:
–decreased resistance to O2 flow from lid
–lens-induced lagophthalmos
–altered CO2 level
–reduced tonicity change
CORNEAL SWELLING
41. THANK YOU
Table of Contents
Feedback on errors, omissions, or suggestions for
improvement are invited. Please contact us at:
iacle@iacle.org
See the following slides explaining the symbols,
abbreviations, and acronyms used in the IACLE Contact Lens
Course