Competency 5.1.4

Question 1

After I&R Advice

Answer 1

• Explain that cannot sleep/swim/shower in lenses
• No contact with H2O for the lenses, do not use saliva to rewet the lenses. Explain risk of acanthamoeba keratitis
• State maximum wear time and wearing schedule to patient
• Include signs of trouble including redness, change in vision or pain. Must seek assistance from us, or A&E if outside working hrs.
• Solutions and case must be replaced every 3 months despite lenses themselves lasting longer
• Provide care book for RGPs

Question 2

RGP Lens Designs

Answer 2

• Spherical designs
• Front surface toric
• Back surface toric
• Bitoric

Question 3

Spherical RGP Designs

Answer 3

• Can cover upto 3DC of astigmatism
• Only has one spherical power and one base curve
• Typically fitted slightly steeper than flattest K to create tear lens

Question 4

Front Surface Toric RGP Deisgns

Answer 4

• Used to correct over 1.25DC of lenticular astigmatism
• uses base down prism to maintain stability due to spherical back surface (usually 1.5^)

Question 5

Back Surface Toric RGP Design

Answer 5

• Rarer design
• Used in cases where a spherical RGP would tilt over a toric cornea

Question 6

Bitoric RGP Design

Answer 6

• Used where over 3.00DC of mainly corneal astigmatism

Question 7

Aspheric vs Spherical RGP Designs

Answer 7

• Aspheric lenses follow the contours of the cornea whereas spherical ones do not
• Aspheric lenses have reduced edge clearance which improves comfort, the increased edge lift in a spherical design may result in discomfort due to lid interaction
• Aspheric lenses allow for less circulation of tears below the lens when compared to a spherical lens design due to peripheral edge design
• Aspheric lenses reduce the effects of spherical aberrations which are particularly important in patients with large pupils.

Question 8

Materials Used in RGP Lenses

Answer 8

• Silicone acrylate
• Fluorosilicone acrylate

Question 9

Oxygen transmission in RGP Lenses

Answer 9

• Addition of fluorine in FSAs allows oxygen molecules to be soaked up whereas SA relies purely on diffusion for oxygen transmission

Question 10

Silicone Acylate RGP Material

Answer 10

Advantages
- Good scratch resistance
- Good vision when there is limited flexure
- Good dimensional stability

Disadvantages
- Lower Dk/t (not fitted for EW)
- can result in 3 and 9 o’clock staining
- Attracts proteins from tear
- More prone to lens flexure

Question 11

Fluorosilicone Acrylate RGP Material

Answer 11

Advantages
- Very high Dk/t (can be EW)
- fewer deposits
- Better wettability

Disadvantages
- Fragile if too thin
- Less consistent dimensional stability

Question 12

Alloa Specsavers RGP Options

Answer 12

• B&L is supplier
• Maxim, maxim toric and maxim MF
• Fluorosilicone acrylate
• Online fitting guide

Question 13

Different RGP Care Regimes

Answer 13

• Boston multipurpose solution
• Multi-step regime

Question 14

Boston Multipurpose Solution Directions

Answer 14

1. Place lenses in empty lens case and fill to top ridges with fresh Boston SIMPLUS Multi-Action Solution. Soak lenses for at least 4
   hours (or overnight) before wearing.
2. After soaking, remove lenses from lens case and rub both sides of the lenses carefully with 4 drops of Boston SIMPLUS Multi-Action Solution in the palm of your hand for 20 seconds. NO SEPARATE
   DAILY CLEANER IS REQUIRED.
3. Rinse for approximately 5 seconds with a steady stream of Boston SIMPLUS Multi-Action Solution to eliminate loosened surface
   deposits and insert lenses.
4. Discard solution from lens case after each use.
5. Clean contact lens cases with digital rubbing with fresh, sterile disinfecting solution. Never use water. Cleaning should be followed by rinsing with fresh, sterile disinfecting solutions (never use water) and wiping the lens cases with a fresh, clean tissue is recommended

Question 15

Multi-Step Regime Directions

Answer 15

1. Rub both sides of lenses carefully with 2-4 drops of Boston Cleaner in palm of your hand for twenty (20) seconds
2. Rinse each side of the lens for at least 5 seconds, or as needed, to remove the cleaner with saline
3. Place lenses in an empty lens case and fill with fresh Boston Original Conditioning Solution. Soak lenses for at least 4 hours (or overnight) before wearing. Use fresh solution for soaking and storing lenses.
4. apply fresh conditioning solution to wet lenses for additional cushioning, if desired, and insert.
5. Rinse lens case with fresh, sterile disinfecting solutions (never use water) and wipe the lens case with a fresh, clean tissue

Question 16

Air Drying RGP Cases

Answer 16

• Make sure no reside is remaining if air drying
• Drying with clean tissue paper is preffered