CL Reviewer Flashcards by Ashley Mendova

he pioneered development of continuous wear of soft CL

John de Carte

How well did you know this?

Not at all

Perfectly

he is considered to be father of RGP

Leonardo Seidner

How well did you know this?

Not at all

Perfectly

he conceived the concept of throwaway lenses

Orlando Battista

How well did you know this?

Not at all

Perfectly

first commercially available disposable lens

Danalens

How well did you know this?

Not at all

Perfectly

he developed the first commercially available disposable lens

Michael Bay

How well did you know this?

Not at all

Perfectly

first commercially available daily disposable CL

Johnson and Johnson

How well did you know this?

Not at all

Perfectly

RGP stands for

Rigid Gas Permeable

How well did you know this?

Not at all

Perfectly

PPMA stands for

Polymethyl-Methacrylate

How well did you know this?

Not at all

Perfectly

he understood that better vision could be achieved by enlarging the retinal image

Rene Descartes

How well did you know this?

Not at all

Perfectly

he proved that cornea played no part in the accommodative process

Thomas Young

How well did you know this?

Not at all

Perfectly

he is considered as father of CL

Sir John Herschel

How well did you know this?

Not at all

Perfectly

he is the first person to apply therapeutic contact device on the eye

William White Cooper

How well did you know this?

Not at all

Perfectly

he devised the first CL for keratoconus

Eugene Kalt

How well did you know this?

Not at all

Perfectly

limitations of keratometry

Small area measured; periphery & apex not measured
Assumes cornea is a spherical surface: accuracy is questionable
Irregular topography not described specifically & sometimes undetected

How well did you know this?

Not at all

Perfectly

the color that indicates the steepest curve in a corneal videokeratography

Red

How well did you know this?

Not at all

Perfectly

CL design where in back surface has two curvature all throughout is

How well did you know this?

Not at all

Perfectly

CL design wherein back surface has two curvature

How well did you know this?

Not at all

Perfectly

gradual change in curvature from center to periphery of optic zone

Aspherical design

How well did you know this?

Not at all

Perfectly

Lens-cornea relationship wherein the CL is more curved than the cornea

How well did you know this?

Not at all

Perfectly

The eccentricity value of the apex of the cornea is roughly

0.50

How well did you know this?

Not at all

Perfectly

TRUE about Reverse geometry design, EXCEPT:
a. central portion of lens is steeper than periphery
b. for post-surgical “plateu” topographies
c. for myopia reduction

How well did you know this?

Not at all

Perfectly

True about back vertex power exceot
a. same w px refractive error
b. combines w LL to provide total refractive correction
c. determined by diagnostic lens
d. checked emperically using K reading

How well did you know this?

Not at all

Perfectly

true about base curve of SCL except
a. aka Sagittal depth
b. tends to be much steeper than K
c. Same as RGP
d. range is 8.00 to 9.2mm

How well did you know this?

Not at all

Perfectly

true about lens diameter of SCL except
a. larger than RGP
b. creates greater sag
c. increase stability & comfort
d. increase tear exchange

How well did you know this?

Not at all

Perfectly

wearing sched where CL is only worn when px is awake

Daily wear

wearing sched wherein CL can be worn 7 days without removal

Extended wear

true of Conventional except a. lens is replaced when there is need for replacement b. typically 12 months for SCL c. px receives one pair at a time d. less lens care required

true of Frequent Replacement except a. aka Programmed replacement b. lens is frequent replaced c. lens is worn in DW basis only d. fewer complications

true of disposable CL except a. one time use b. no lens care c. more convenience d. less costly

true of Handling tints except a. does not aid in lens handling b. almost all tints have handling tints c. can be seen more easily d. not meant to change eye color

true of Opaque tints, except a. change irises to diff color b. may see some iris through clear pupil c. mask underlying iris color d. no blur on edge

true of spincasting except a. oldest form of CL manufacturing b. very expensive c. discovered by Witcherle d. reproducible

FDA grouping of CL with low water content & ionic

Group 3

FDA grouping with high water content and non-ionic

Group 2

FDA grouping with low water content and non-ionic

Group 1

FDA grouping with high water content and ionic

Group 2

amount of astig brought by refractive surfaces especially cornea is called

Residual

According to FDA, CL can be classified as low water content if

it contains less than 50% water

purpose of inversion markers

tells if lens is inside-out

range of water content in SCL

25 to 74%

wearing sched wherein lenses are worn 30 days straight

Continuous wear

SCL worn alternately with eyeglass prescription is called

Occasional wear

which scenario is the safest

D. A CL designed for continuous wear used in daily manner

which scenario is the least safe

C. A CL designed for daily wear used in continuous manner

true about lacrimal lens in RGP except

D. using thick lens formula in solving the power

true about low water content hydrogel except a. poor durability handling b. fewer deposits c. lower Dk d. can be made thinner

true about high water content except a. higher dk b. used more often for extended wear c. more deposits d. can be made thinner

if BC of CL is steeper than K reading in HCL, the power of lacrimal lens will be

Plus

if BC of CL is flatter than K reading in HCL, the power of lacrimal lens will be

Minus

if BC of CL is on-k in HCL, the power of lacrimal lens will be

Plano

the LL in SCL is said to always be

Plano

if cornea is astigmatic, the power of LL will be

Cylindrical

the amount of astig manifested with CL on the eyes called

Residual astig

true about water content except a. water is bound within hydrophilic polymer matrix to provide flexibility & oxygen permeability b. amount of water determines material characteristics c. very important in silicone hydrogels since O2 depends on it

NO EXCEPTION

advantages of SCL over HCL except a. better initial comfort b. easier part time wear c. more spectacles blur d. more frequent replacement

advantages of HCL over SCL except a. sharper VA b. better deposit resistance c. greater durability d. cost is higher

acceptable blink movement in primary gaze

0.5 to 2mm

for conventional hydrogel CL the grouping which would be best will be

Group 2

CL modality schedules by optometrist not manufacturer

CL modality most convenient

Daily disposable

CL modality that a pair can be used for 12 months

Conventional

CL modality where a CL can be worn for a month

Monthly disposable

CL modality that needs the most contact solution would be

Conventional

Cl modality where confusion will arise in usage of lens

Frequent replacement

the cheapest CL modality

Conventional

type of lens where oxygen transmissibility is so high it can be worn for 30 days straight without removal

Continuous wear

type of lens where lens may be used only when px is awake

Daily wear

type of sched where px alternates usage of CL & spectacle lens

Occasional wear

wearing sched suggests lens can be worn 7 days straight

Extended wear

wearing sched that we encourage to our px no matter what oxygen transmissibility of lens is

Daily lens (chatgpt)

lens with Dk/t of 23 will be good for

Daily wear

lens with Dk/t of 50 will be good for

Daily wear (chatgpt)

lens with Dk/t of 87 will be good for

Continuous wear

silicone hydrogel lens is the only one allowed for this modality

Continuous wear

the LL produced when BC radius of Cl is flatter than curvature of cornea

Minus

primary advantage of SCL over HCL

- clarity of vision - comfort - ease of wearing

a CL with Dk of 58 is prescribed to px, what will be best management for px

- Advise px to do and extended wear only limit to 2 or 3 nights of overnight wear - Advise px to just wear the lens when px is awake - chatgpt