Contact Lens 1: SCL Care Flashcards
Contact Lens Types
- Soft: 2 types of Material?
- 2 Types of Replacement Schedules?
- Hydrogel and Silicone Hydrogel (Si Hy)
- a. Disposable (1-day, 1-week, bi-weekly, monthly)
b. Conventional: Quarterly and Yearly
CL Types
- Gas-Permeable: Size (2)?
- Hybrid: 2?
- Corneal and Scleral
2. GP Center and Surrounding Soft Skirt
CL Types
- Implantable CLs
a. Verisyse: Sits where?
b. Visian: Sits where?
- a. Sits ANTERIOR to IRIS (AC ICL)
b. Sits b/w Iris and Crystalline Lens (PC ICL)
Lens Contaminants: Multiple things…name a bunch?
- Microorganisms
- Viruses
- Prions
- Cell Debris
- Air-borne Contaminants
- Tear Components (Proteins, Mucus, Lipids)
- Skin Lipids
- Finger-Borne Debris
- Cosmetics
- Care Products
- By-products of any interactions b/w lens, care products and Contaminants
CL Care
- Three Main Components and what they do:
a. Clean
b. Rinse
c. Disinfect
- a. Removes Loosely Bound Foreign Matter
b. Removes Loosened Deposits
c. Kills/Deactivates Potential Pathogens
- What does CRADLE Stand for?
a. Analagous to what?
- Clean, Rinse, And Disinfect Lenses Everyday
a. Diswasher Analogy (Clean dishes, rinse them, put them thru the dishwasher)
CL Care
- Nature of SCL Materials: Susceptible to what?
- Prevent Contamination with what?!
a. Critical if not replacing lenses when?
b. Daily Disposable lenses avoid the need for what?
- to CONTAMINATION!
- with DISINFECTION!
a. Daily
b. for Care Solutions
CL Solution Paradox
- Solutions need to be 2 things.
- STRONG enough to KILL MICROBES, AND Mild Enough NOT to harm Corneal Cells
SCL Disinfection
- Physical (4)
- Chemical (2)
- Thermal, Microwave, UV, and Ultrasound
2. Multipurpose and Oxidative
- Thermal Disinfection: Requires what 2 things?
- Saline
a. Solution of what?
b. Substitute for CL Solution?
c. What is added to OPTIMIZE pH?
d. Saline can be 1 of 2 things?
e. Non-Preserved must be discarded how many days after opening? Unless it’s what?
- Heat Unit + Soaking Solution (SALINE)
- a. of Salt Water
b. NO!
c. A Buffer
d. It can be Preserved or Non-Preserved
e. 30 days after opening; Unless it’s AEROSOL
Thermal Disinfection: Advantages
- Cost?
- Effective against what forms of Bacteria?
a. What 3 things dis she have listed?
- CHEAP!
- ALL forms of bacteria
a. Acanthamoeba (cyst and Trophozoite forms); HIV; Pseudomonas
Thermal Disinfection: Disadvantages
- Bakes on what?
- What does it do to the life of the CL?
- Contraindications? (3)
- on Deposits (increased complications?)
- Shortens the Lens life (Yellowing)
- a. GPs
b. Lenses w/MORE than 55% Water Content
c. Silicone Hydrogel Lenses
Microwave Disinfection
- Is it good?
- Power level needed?
- Time needed?
- Lens Parameter changes may occur, but are generally what?
- What buildup has been reported?
- Rapid and Effective
- Low Power (10%)
- 15 Minutes Max
- generally small
- Salt Crystal Buildup
* More studies are needed
UV Disinfection
- Purilens System
a. Amt of time? - Mechanism of Action?
a. How does it work?
b. What light?
- *Only currently available system
a. 15 minute exposure to UV-C Radiation - Agitation + Light
a. Shear Waves –> Whirlpool Effect –> Debris Removal
b. UV-C Light = Germicidal
UV Disinfection: Purilens
- Advantage?
- 2 Disadvantages?
- Preservative Free
2. a. Not Si-Hy approved and Not GP approved
Purilens: Steps
- Rinse lenses with what solution. Then place them in what?
- Place this into what?
- Fill it with what?
- Place top on Unit and let it run for how long?
- Lenses are shielded from direct what?
- with Purilens Solution; Place in Lens Holder
- into Cleaning Chamber
- with Purilens Solution
- for 15 minutes
- from Direct UV Exposure
Chemical Systems (2)?
- Multipurpose Solutions (MPS)
and
- Oxidative Systems
CL Solution Components
- Surfactant does what?
- Wetting Agent does what?
- What other component?
- Lowers Surface Tension b/w Liquid and Solid
- Enhances Lens Wettability
- Disinfectant
Disinfection standards are determined by what 2 organizations?
ISO (International Organization for Standardization)
and
FDA (US Food and Drug Administration)
Disinfection Standards
- Standard Strains?
- 2 Types of Testing?
- 3 bacterial and 2 fungal
- a. Standalone (Solution alone)
and
b. Regimen (Rub, Rinse, Soak according to label)
Organisms used in all Testing
- 3 Bacterial strains?
- 2 Fungal Strains?
- a. Pseudomonas Aeruginosa
b. Serratia Marcescens
c. Staphylococcus Aureus - a. Candida Albicans
b. Fusarium Solani
Multipurpose Solutions (MPS)
- Combination of what 3 things?
a. Bottle care?
b. No-rub is promoted by manufacturers to what?
c. Different Biocide in what?
d. Different what?
- Cleaning, Rinsing, and Disinfection
a. 1 Bottle Care
b. to Lens Wearers
c. in Each Brand
d. Different Soaking Times
Disinfectants
- Quarternary Ammonium Compounds (1)
- Alcohols, Acids and Related Compounds (1)
- Mercurials (1)
- Biguanides (2)
- Oxidizers (1)
- Chelating Agents (1)
- PQ-1
- Sorbic Acid
- Thimerosal
- PHMB and Alexidine
- Hydrogen Peroxide
- EDTA
Quarternary Ammonium Compounds (eg BAK, PQ-1)
- BAK
a. Has what 2 types of actions?
b. Cytotoxic to what?
c. Binds to SCL matrix and could be released into what?
d. NOT used in SCL solutions due to what? - PQ-1
a. found in what 3 solutions?
b. Minimal Tissue response at what concentration level?
- a. Antifungal and Antibacterial Actions
b. to Corneal Epithelium
c. and could be released into tears
d. due to this potential toxicity - a. Opti-Free, Biotrue, and Revitalens
b. Minimal Tissue Response at Low Concentration