CL 2-1: Intro to GPs Flashcards
1
Q
- GPs: Better Vision than SCL or SRx at Distance/Near?
2. CSF: GPs were best at what?
A
- Distance
2. Middle and High Spatial Frequencies (then SCL then Spectacles)
2
Q
O2 to Cornea
- Why do they provide more O2 than SCL?
A
- GPs Move more than SCL, and are less reliant on Material Dk to provide O2 to the Eye
So you get LESS HYPOXIA (neo and corneal edema)
3
Q
Stability and Durability
- Tearing?
- How often are they replaced?
- Deposits on the Lens?
A
- None
- usually every year or prn
- No. LESS. (Smooth finish and lack of Water Retention = they harbor fewer deposits)
* More stability/durability means better value for patients while still maintaining a high profit margin.
4
Q
- 3 Main types of IRREGULAR ASTIGMATISM GPs can correct?
A
- Corneal Scarring
- Keratoconus
- Pellucid Marginal Degeneration
5
Q
Corneal Reshaping (Ortho-K)
- Lenses create pressure on the cornea: what does this do?
- Goal for vision is to stay clear enough throughout the day so lenses are only needed when?
A
- Compresses the Epithelial Cells Indirectly
a. MYOPIA: CENTRAL Flattening
b. Hyperopia: PARACENTRAL Flattening w/relative Central Steepening - At Night
6
Q
Why are CLs better than GPs? (3)
A
- Pt looks thru Optical Center more often
- Less Chromatic/Spherical Aberration
- Elimination of Prismatic Effect
7
Q
GP Comfort
- Lens Awareness: Driven mostly by what?
a. Lens awareness is not as much due to what?
A
- By the EYELID Sliding over the edge of the CL
a. Not as much due to CORNEAL Sensation
8
Q
Language
- What 3 things shouldn’t be said?
- What should the patient say?
A
- Rigid Lenses; Hard Lenses; Rigid Gas-permeable CLs (RGPs)
2. Gas-Permeable CLs (GPs)!!!
9
Q
Patient Presentation
- Terms to Avoid (what should be used)
a. Hurt
b. Pain
c. Discomfort
d. Irritation
e. Uncomfortable
A
- a. Initial Sensation
b. Edge Awareness
c. Lid Sensation
d. Itching
e. Lid Awareness
10
Q
4 Pros of Using Anesthetic during the fitting
A
- Greater Pt satisfaction
- Improved Initial Comfort
- Less Initial Chair time
- Less Reflex Tearing
11
Q
4 Cons of using Anesthetic during the fitting (DEMS)
A
- Does not help w/lid sensation
- Eye Rubbing
- Misleading
- Staining
12
Q
Assessing GP Candidacy
- Good GP Candidates (5)
A
- Current/previous GP wearer
- Failed SCL wearer (depends on reason)
- Pts prone to SCL complications (GPC; Inflammation/infection; SEAL)
- Pts desiring sharper vision
- Pts w/Astigmatism
13
Q
Pre-Fit Exam
- BCVA: Special consideration needed if BCVA is what?
- Good Refraction: Why is this needed?
- What determines INITIAL diagnostic GP?
A
- is reduced in 1 eye or both (INFORMED CONSENT)
- Reduces fitting time; and Enhances Results
- K-Values
14
Q
K-Values
- If Cornea is TOO STEEP: What do you do?
- If TOO FLAT, what do you do?
A
- Put in a +1.25 D on Obj side of Keratometer, then Approximate by ADDING +8.00 D to reading
- Use -1.00 D lens, and SUBTRACT -6.00 D from reading
15
Q
Persistently Irregular Mires indicate Irregular Astigmatism. (what 4 are the main ones?)
A
- Corneal Scarring
- Corneal Dystrophies
- Keratoconus
- Pellucid Marginal Degeneration
16
Q
Upper Lid Position
- Above upper limbus
- At Upper limbus
- Below upper limbus
A
- Interpalpebral (Smaller Diameters)
- Interpalpebral (Smaller diameters)
- Lid Attachment
17
Q
Vertical Palpebral Aperture
- Why would Smaller Palpebral Apertures may Benefit from GP CLs?
A
- cuz they’re usually smaller than SCLs (8.0-10.00 mm vs. 14-15 mm)