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Flashcards in Prosthetics e-lectures Deck (42)
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1

procedure where the entire eyeball is removed

enucleation

2

procedure with removal of eyeball's contents and leaving the scleral shell intact, EOMs may still be attached

Evisceration

3

procedure with removal of all orbital contents including eyeball, extra ocular muscles, fat and connective tissues where sometimes the eyelid is removed as well and the maxilla (upper jawbone and cheek)

Exenteration

4

it is hard to differentiate with these two types of post-surgical eyes?

enucleation with implant vs. evisceration (without implant)

5

enucleation without implant appears as

an empty socket

6

when do you use a scleral shell or prosthetic scleral shell?

Phthisis bulbi: ocular end stage disease
(atrophy, shrinkage, and disorganization of the eye ball and intraocular contents)

7

prosthetic eyes are made of a curved disc of plastic with a min center thickness of

2mm

8

what are some ways to help tell if a prosthetic is a right or left side?

-nasal edge is more pointy
-superior trochlear curve
-steeper superior F2 curve
-flatter inferior F2 curve

9

a shell eye is a curved disc of plastic with a center thickness of

less than 2mm

10

a shell eye is designed to cover:

an intact eye or shallow socket
(it may have open pupil for light perception)

11

reasons to get implant vs. no implant

-implant: allows for smaller ocular prosthetic
-no implant: fewer complications

12

reasons to get solid vs. porous implants

solid: fewer complications
porous (integrated implants): better motility, allows fibrovascular growth

13

what are two orbital implant complications?

-migration: (movement of implant laterally or vertically)
-extrusion: (implant boring out of conjunctival surface)

14

is occlusion necessary in a routine eye exam on a prosthetic patient?

no

15

what are some things to check for in gross evaluation of prosthetic eye

-binocular eye alignment
-vertical palpebral fissure size and symmetry
-iris diameter and color symmetry
-pupil diameter (habitual eye, bright and dim)
-sclera color (white, vessels)

16

how often should a prosthetic be replaced?

5-7 years

17

what are some prosthetic specific examination components?

-eyelids: symmetry and vertical palpebral fissure height
-iris: natural iris color, HVID, Nevus
-cornea: opacity, arcus, etc.
-pupil size: dim, moderate, and bright illumination
-strabismus

18

prosthetic eye fitting: step 1

-determine ideal white or clear shape
-examine overall socket shape (foveal, triangular, other)
-diagnostic fitting vs. injection molding

19

prosthetic eye fitting: step 2a

finalize overall shape, comfort, fit, (-) rotation

20

prosthetic eye fitting: step 2b

prosthetic scleral shell
-gross evaluation: adequate tear exchange, excessive blanching, bubbles are acceptable, excessive edge lift
-biomicroscopy: ocular surface staining

21

prosthetic eye fitting: step 3

determine color and shape
(color match iris and sclera, iris position and size, pupil size)

22

prosthetic eye fitting: step 4

dispense, follow ups (2-4 weeks for initial shape, six month for polish, and annual examination)

23

what are some common prosthetic complications?

-blepharitis
-conjunctivitis
-incomplete eyelid closure
-natural iris and scleral color changes

24

problem with scleral shells (acrylic)

made of plastic (PMMA), but could not wear for extended periods of time due to no tear exchange

25

pros and cons to introduction of corneal PMMA contact lenses

smaller design allowed for tear exchange and O2 transmissibility via movement, but movement would cause shifting of iris print

26

examples of when to use of specialty contact lenses for non-functioning eyes

-opacified cornea
-iris atrophy
-white pupil
-corneal scar
etc.

27

examples of when to use of specialty contact lenses for functioning eyes

-iris atrophy (large pupil)
-strabismus
-corneal scar (not in visual axis)
etc.

28

definition of "iris occlusion"

iris pigment on the lens. pupil is clear/open

29

definition of "pupil occlusion"

black pupil at the center of the lens. no vision

30

definition of "iris and pupil occlusion"

iris pigment on the lens and black pupil at the center of the lens

31

tinted SCL (A)

-uniform color, no iris details
-translucent

32

printed SCL (B)

-ready-made or stock lens
-manufactured, some iris details
-opaque

33

hand-painted SCL (C)

-made to order, custom iris details
-opaque

34

what are some characteristics of tinted lenses?

-homogenous
-translucent
-unlimited base curve, power, diameters, iris and pupil diameters
-best for matching dark eyes

35

what are some other uses for tinted lenses?

-red/green color deficiencies
-achromatopsia
-low vision patients

36

what are some characteristics of printed lenses?

-iris details
-complete occlusion possible
-limited BC, power diameters, and iris/pupil diameters
-best for matching all eyes
-replicable
-fitting set available

37

what are some characteristics of hand painted lens characteristics?

-iris, pupil, scleral details
-complete occlusion
-unlimited BC, PWR, diameters, iris and pupil diameters
-best for matching all eyes

38

you should only use clear care for what type of lens

hand painted lenses

39

what are some ocular disfigurements patients may want to conceal

-iris abnormality: coloboma, scar, irregularity
-corneal abnormality: scar, band keratopathy
-pupil abnormality: white pupil

40

what are some reasons patients may want to improve visual function with prosthetic lenses?

-iris abnormality: traumatic iris atrophy, aniridia
-symptoms: glare

41

reasons for an iris occluding (open pupil) lens:

-albinism: lacking iris color
-aniridia: lacking an iris
-coloboma: iris opening (usually inferior)
-iris atrophy/ fixed dilated pupils: abnormal pupil function

42

reason for pupil occlusion (with or without iris details)

-ambylopia: patching of the good eye
-diplopia: binocular double image which cannot be suppressed or fused
-leukocoria: white pupil, usually from posterior ocular scar tissue
-corneal abnormalities: corneal scar, band keratopathy
-strabismus: occluding one eye
-achromatopsia: patients with rod-cone dystrophy
-color vision difficulties: red magenta lens