CL Fit and Follow Ups

Question 1

What are the two methods of fitting?

Answer 1

1. Trial Fitting - trial and error

2. Empirical Fitting - Fitting on paper by following all the guidelines and formulas

Question 2

What are the Good Fit Standards for Contact Lenses?

Answer 2

1. Maximum VAs
2. Good Centration
3. Maximum Comfort
4. Good lens movement during blinking/eye movements with no scleral indentation
5. Good “push up/finger” test → to ensure the lens isn’t too tight
6. No curling of lens edges
7. No conjunctival drag (minimal pressure on the conj.)
8. A soft conventional lens should be fit as flat as possible (it will steepen over time)
9. Clear and undistorted K mires when views in situ.

Question 3

What classifies a “Bad Fit?”

Answer 3

If any of the 9 good fit standards are not met

Question 4

Which Steps of the good fit standards are most important?

Answer 4

The first 3:

1. Maximum VAs
2. Good Centration
3. Maximum Comfort

Question 5

How much do you want a HEMA lens to move on blink/eye movement?

Answer 5

Blink - 1 mm
Upward Gaze - 1 mm
Lateral Gaze -1 mm

Question 6

How much do you want a SiHy lens to move on blink/eye movement?

Answer 6

Blink - 0.5 mm
Upward Gaze - 0.5 mm
Lateral Gaze -0.5 mm

Question 7

What are the 11 steps of Fitting Lenses?

Answer 7

1. Patient History - medical, occupational/hobbies, CL history
2. Vertex OD’s Rx
3. VAs with Spectacles/Unaided
4. K Readings (3x then average)
5. Slit Lamp Exam (white light and blue light)
6. Tear Tests (TBUT, Schirmer’s Test, Tear Lake Eval.)
7. Discuss Lens Options/Modalities
8. Trial Fit (Equilibrate, Slit Lamp, Over-refract)
9. Patient Instruction (Insertion/Removal/Hygeine)
10. Give Wearing Time Schedule
11. Schedule Follow Ups (Wear lenses for 3-4 hours before appt)

Question 8

What are the steps for trial fitting GPs?

Answer 8

1. Insert Lens
2. Equilibration period (until tearing stops)
3. Slit lamp (with fluorescein)
4. Over-refract with spheres

Question 9

What are the steps for trial fitting SCLs?

Answer 9

1. Insert Lens
2. Equilibration period (20 minutes)
3. Fit evaluation with Keratometer
4. Slit Lamp (NO fluoroscein)
5. Over-refract with spheres

Question 10

On the follow up appointment, why do you want the patient to wear the lenses for 3-4 hours before returning?

Answer 10

It it is present, edema can set in right away, but it takes 3-4 hours to see the effects on the eye

Question 11

What range are we allowed to over-refract and dispense? Why?

Answer 11

+/- 0.50 D

This can account for overtaxing, tear film and lens thickness

Question 12

What are the steps for a 6 month follow up?

Answer 12

1. Reminder Call (Wear lenses for 4 hours before appt.)
2. Update patient file
3. Ask CL questions
   - Do you smoke, swim, sleep or shower in the lenses?
   - How is the lens on insertion, during the day, on removal?
   - Wearing schedule
   - Vision difficulties
4. VA test (with CLs - monoculab/binocular, near and distance)
5. Assess CL fit
6. Use Keratometer to assess SCL fit (Flat, tight and 3 point touch)
7. Watch patient remove the lens
8. Inspect the lens for knicks, tears, deposits
9. Have patient demonstrate lens hygiene
10. Perform Eye Health Exam
11. Slit lamp with Fluoroscein
12. VA with glasses (note any changed)
13. K readings OU (note condition of mires)
14. SOAP
15. Recommendations from documented findings
16. Schedule Follow Up and give wearing schedule

Question 13

What does SOAP Stand for?

Answer 13

S - Subjective: Information the patient is giving you
O - Objective: The things you can see
A - Assessment: For example, change solution, adjust wear time, adjust modality, adjust material
P - Plan: What you will order/dispense/change and how. This includes follow up and wear schedule

Question 14

What are 5 compromises patients wearing multifocal lenses will need to deal with?

Answer 14

1. Reduced Stereo-acuity
2. Loss of monocular/binocular contrast sensitivity
3. Reduced of Fluctuation VAs
4. Image Jump
5. Changes in binocular balance

Question 15

What are the 3 goals of Presbyopic fitting?

Answer 15

1. Minimize any induced problems
2. Seek compromises that are acceptable to the patient within the context of their normal visual environment and visual needs
3. Inform the patient of what. to expect with their type of fit

Question 16

What type of vision is the dominant eye used for?

Answer 16

Takes over distance vision

Question 17

What type of vision is the non-dominant eye used for?

Answer 17

Takes over near vision

Question 18

What are the 5 options for CLs with Presbyopic fits?

Answer 18

1. Glasses.CL Combo - distance CLs with reading glasses over top or reading CLs with distance glasses over top
2. Mono Vision
3. Modified Monovision (D-SV Distance, N-Multifocal)
4. Bifocal contact lenses
5. Multifocal contact lenses

Question 19

You are given a prescription of

• 3.00 -0.50 x 180 add +2.00
• 2.75 -0.50 x 180

How would you fix this with SV Distance CLs and reading glasses?

Answer 19

OD -3.25
OS -3.00

with +2.00 readers

Question 20

You are given a prescription of

• 3.00 -0.50 x 180 add +2.00
• 2.75 -0.50 x 180

How would you fix this with SV Readings CLs and Distance glasses glasses?

(After I answer the first question… Why not -1.25 OD and -1.00 OS?)

Answer 20

OD -1.00
OS -0.75

with -2.00 readers

(Since they are using the CLs for reading, you want to start by dispensing LESS minus)

Question 21

What are 4 pros and 2 cons for glasses over CLs?

Answer 21

Pros
✓ Easiest method (least chair time)
✓ Full distance correction
✓ Little adaptation period
✓ Little compromising

Cons
𐄂 Needs two types of correction (CLs and Glasses)
𐄂 Only two areas of vision (distance and near)

Question 22

What are they steps of fitting someone in mono vision?

Answer 22

1. Determine the Dominant eye (Fogging or Farmer’s Triangle) (D-Distance, N-Near)
2. Over refract with +/- 0.25 to 0.50 D to meet the patient’s binocular visual needs

Question 23

You are given a CL Rx of
OD -2.00 -1.00 x 180 add +1.50
OS -2.25 -1.00 x 180

What would you order?

Answer 23

OD -2.00 -0.75 x 180

OS -0.75 -0.75 x 180

Question 24

What is the typical adaptation period for Monovision CLs?

Answer 24

The brain will select which eye should e used at any given time over 2-3 weeks

Question 25

What is important when considering mono vision to maintain stereopsis?

Answer 25

Do not have more than 2.00 D of separation between the two eyes

Question 26

What are 8 pros and 7 cons to monovision?

Answer 26

``` Pros ✓ Least Complicated presbyopic fit ✓ Easiest to trial ✓ Good binocular contrast ✓ Lease Expensive ✓ Large range of designs/materials ✓ No additional fitting sets required ✓ Patient quickly accepts or rejects this technique ✓ Compromise comparable to glasses ``` Cons 𐄂 Peripheral vision when driving (shoulder check) 𐄂 Reduction in stereopsis 𐄂 Unsuitable for amblyopic patients 𐄂 Loss of contrast sensitivity (Black/White) 𐄂 Reduced intermediate vision as add increases 𐄂 Headlight glare 𐄂 No Pilots

Question 27

What are the two methods of fitting modified monovision?

Answer 27

1. Using a multifocal in one eye and single vision in the other (D - Distance only N - Multifocal design) 2. Modifying the distance or near vision to meet the patient's needs

Question 28

Using modified monovision how would you fit a 38 year old with distance priority with a prescription of: OD -3.00 (no add) OS -3.00 Distance VA was 20/20, near VA was 20/30

Answer 28

Fit with -2.75 OU. This under corrects the distance a little bit but still increases the reading VAs.

Question 29

Using modified monovision, how would you fit a OD Dominant Trick driver with distance priority? CL Rx: OD -1.00 -0.25 x 175 add +2.00 OS -1.00 sph

Answer 29

Fit: OD -1.25 sph OS -1.00 +1.00 add Round OD SE to more minus to prioritize distance nd give half the add to achieve intermediate

Question 30

Using modified monovision, how would you fit a OD Dominant Accountant with near priority? CL Rx: OD -1.00 -0.25 x 175 add +2.00 OS -1.00 sph.

Answer 30

Fit: OD -1.00 sph OS -1.00 +2.00 add Round OD SE to less minus to prioritize near and give full add to achieve more near

Question 31

What are 2 pros and 7 con to modified monovision?

Answer 31

Pros ✓ Distance vision in both eyes ✓ Easy adaptation to bifocal lenses as add power increases (this method grows with the patient) Cons 𐄂 Peripheral vision when driving (shoulder check) 𐄂 Reduction in stereopsis 𐄂 Unsuitable for amblyopic patients 𐄂 Loss of contrast sensitivity (Black/White) 𐄂 Reduced intermediate vision as add increases 𐄂 Headlight glare 𐄂 No Pilots

Question 32

What is a common phenomenon with monovision contact lenses?

Answer 32

Ghosting - Occasional fuzziness surrounding an otherwise clear object - Blur of a bright object against a dark background (headlights)

Question 33

What are the two basic designs of Multifocal Designs?

Answer 33

1. Translating/Alternating - Executive Bifocal | 2. Concentric/Simultaneous - Bulls Eye

Question 34

Explain Translating/Alternating Multifocal Lenses

Answer 34

Alternate between two powers as your gaze shifts up/down (an executive bifocal in a GP lens with an obvious line of separation)

Question 35

Explain how Concentric Multifocal Lenses work

Answer 35

The patient looks through both powers at the same time and brain learns how to choose what power to use (can be distance @ centre or near @ centre). Typically the design has at least two rings within the pupil size

Question 36

What are some pros and cons to Translating Multifocals?

Answer 36

Pros ✓ Distance and Near VAs comparable to glasses ✓ Minimal reduction in stereopsis ✓ Minimal reduction in contrast Cons 𐄂 Complex fit 𐄂 Game Dependant (troublesome on stairs) 𐄂 Intermediate correction is not always possible 𐄂 Needs the right patient (tight lids and lower lid at lower limbus)

Question 37

When fitting Translating Multifocals, should you fit flatter or steeper and what dK value?

Answer 37

You fit flatter than K to allow for more movement, and therefore you would want a higher dK

Question 38

What is a Tangent Streak? How does it work?

Answer 38

The most common Translating Multifocal Design. You fit a patient with normal fissure size, normal lid tension and they must have lower lid at limbus

Question 39

What is the difference between concentric multifocals and aspheric multifocals?

Answer 39

Concentric have rings and aspheric do not but they use the same principle but have better optics

Question 40

What are 7 pros and 5 cons to concentric multifocals?

Answer 40

``` Pros ✓ Available in SCL or GP lenses ✓ Vision correction in all gaze directions ✓ Maintains stereopsis ✓ No rotational stability needed ✓ More comfortable ✓Availably as singe-use trials ✓ Easier to fit ``` Cons 𐄂 Visual adaptation 𐄂 Loss of low light contrast 𐄂 Lens centration is critical 𐄂 Usually looses one line on the Snellen Chart 𐄂 Difficult to establish over refraction end point

Question 41

How should you fit Concentric Multifocals?

Answer 41

Fit steeper tan K to achieve good contraption and minimal movement