SCL Solutions - Part 1

Question 1

Disinfectant

Answer 1

Eliminates harmful bugs from CL

Question 2

Preservative

Answer 2

Controls growth of bugs

Question 3

A care regimen has many roles…

Answer 3

• Proven disinfection
• Removal of deposits
• Enhanced comfort
• Has to be non-toxic, compatible w/ all materials, simple, quick, inexpensive!

Question 4

Pros to heat disinfection (1970s)

Answer 4

Cheap
Simple
Very effective (pseudomonas, HIV, acanthamoeba)

Question 5

Cons to heat disinfection

Answer 5

Open to abuse (saline)
Increased deposits (baked onto lenses)
Increased red eye
Increased GPC
Distorted lenses
Not portable!

Question 6

What are the original chemical disinfectants

Answer 6

Thimerosal (THI)
Chlorhexidine (CHX)
Benzalkonium chloride (BZK) - RGP ONLY!

Question 7

Pros to chemical disinfection

Answer 7

Cheap
Portable
Simple
Effective

Question 8

Cons to chemical disinfection

Answer 8

Open to abuse (topping up)
Discoloration (mercury turned lenses grey!)
Sensitivity issues (up to 40% after 3 yrs)

Question 9

Four classic signs of preservative HS?

Answer 9

Red eye
Corneal staining
GPC
Corneal infiltrates

Question 10

What concentration of hydrogen peroxide is used as a disinfectant?

Answer 10

3% (30 000 ppm)

Question 11

What concentration of hydrogen peroxide is used as a preservative (in salines)?

Answer 11

0.006% (60 ppm)

Question 12

At what concentration does hydrogen peroxide start to sting?

Answer 12

150-200 ppm

Question 13

Problems w/ peroxide

Answer 13

Red eyes

Diffuse corneal staining

Question 14

Most effective disinfecting system

Answer 14

3% peroxide soak overnight (neutralize in the am)

Question 15

What is the problem w/ small preservatives/biocides?

Answer 15

Taken up into lens, leaving less for disinfection (reduced efficacy)
Subsequent release onto eye causes corneal staining or irritation

Question 16

What preservative does Alcon solutions (Opti-free) use?

Answer 16

Polyquad

Question 17

What preservative does B&L (Renu, BioTrue) use?

Answer 17

Polyhexanide (PHMB)

Question 18

What preservative has the largest molecular weight?

Answer 18

High MW Polyquad

followed by High MW PHMB

Question 19

What are the major biocides?

Answer 19

Hydrogen peroxide
PHMB
Polyquad
Alexidine
Aldox

Question 20

What are the major surfactants?

Answer 20

Tetronic 1107, 1304, 1304 plus C9-ED3A

Pluronic F-127

Question 21

What are the major wetting agents?

Answer 21

CMC
HPMC
HA
EOBO

Question 22

What are the major chelating agents?

Answer 22

EDTA
Sodium citrate
Hydranate

Question 23

What solutions use Peroxide as a biocide?

Answer 23

AOSept
ClearCare (AOSept Plus)
Ultracare (Oxysept 1-step)

Question 24

What solutions use Polyquad?

Answer 24

OptiFree Express
OptiFree RepleniSH
OptiFree PureMoist

Question 25

What solutions use PHMB? (Most of them…)

Answer 25

``` ReNu Sensitive Eyes ReNu Fresh SoloCare AQUA Complete Easy Rub All in One Light ```

Question 26

What is Alexidine? What solution is it used in?

Answer 26

``` Bisguanide antiseptic (used in mouthwash) Related to chlorhexidine ``` Used in Complete RevitaLens (with polyquad)

Question 27

What is MAPD (Aldox)? What solution is it found in?

Answer 27

Fungicide | In OptiFree Express/RepleniSH/PureMoist

Question 28

What two preservatives are used in B&L Biotrue?

Answer 28

PHMB and Polyquad

Question 29

What are the two components of a surfactant?

Answer 29

``` Hydrophilic head (water soluble) Hydrophobic tail (water insoluble) ```

Question 30

What are the two functions of a surfactant?

Answer 30

Detergent (cleaner) - remove debris, deposits... | Aid in wetting of interfaces

Question 31

What are the three surfactants?

Answer 31

Poloxamer (Pluronic F87, F127) Poloxamine (Tetronic 1304, 1107) Aqualube (Cremophor RH40)

Question 32

What are the traditional polysaccharide-based wetting agents?

Answer 32

CMC HPMC HA

Question 33

Surfactant block copolymers (wetting agents)

Answer 33

Poloaxamines Poloxamers EOBO

Question 34

What solutions use Tetronic 1304 as a wetting agent?

Answer 34

Alcon OptiFree Express/RepleniSH, PureMoist

Question 35

What solutions use Tetronic 1107 as a wetting agent?

Answer 35

B&L - Renu Fresh/SensitiveEyes, BioTrue

Question 36

What solutions use Tetronic 904 as a wetting agent?

Answer 36

AMO RevitaLens

Question 37

What solutions use Pluronic F87 as a wetting agent?

Answer 37

AMO Complete Easy Rub

Question 38

What solutions use Pluronic 17R4 as a wetting agent?

Answer 38

CIBA Vision ClearCare

Question 39

What solutions use EOBO as a wetting agent?

Answer 39

OptiFree PureMoist

Question 40

What chelating agent is found in EVERY CL solution and binds metal ions?

Answer 40

EDTA

Question 41

How does EDTA work?

Answer 41

Binds metal ions that bugs need to metabolize | Acts synergistically w/ preservative to kill bugs!

Question 42

What is the ONE solution that doesn't use EDTA?

Answer 42

OptiFree RepleniSH

Question 43

What solutions use sodium citrate as a chelating agent?

Answer 43

OptiFree Express/RepleniSH/PureMoist

Question 44

What does sodium citrate do?

Answer 44

Opens poles to help w/ protein removal | More relevant w/ older hydrogel materials

Question 45

What solution uses Hydranate?

Answer 45

Renu Fresh

Question 46

What does Hydranate do?

Answer 46

Opens pores to help w/ protein removal | More relevant w/ older hydrogel materials

Question 47

What are two ways to neutralize Hydrogen Peroxide, post-disinfection?

Answer 47

``` Platinum disc (ClearCare) Enzymatic (UltraCare - HPMC coated tablet, Vit B12 Indicator) ```

Question 48

How do Clear Care and UltraCare compare in speed of neutralization?

Answer 48

ClearCare starts neutralization right away. Swift decrease in peroxide concentration. UltraCare neutralizes slowly for the first 25 mins… reaches same concentration of ClearCare after an hour.