Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anterior Segment > Intro to Refractive & Cataract Surgery > Flashcards

Intro to Refractive & Cataract Surgery Flashcards

1
Q

the cornea has how much power in diopters? the lens?

A 
cornea = 40.00 D
lens = 20.00 D
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

corneal refractive surgery changes what?

A

corneal curvature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

when treating myopia with refractive surgery, what do you do to the cornea?

A

flatten the central cornea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

when treating hyperopia with refractive surgery, what do you do to the cornea?

A

steepen the central cornea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is the process called when you sculpt the cornea?

A

keratomileusis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is a parallel faced corneal disc?

A

microkeratome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what refractive procedure was an accidental finding that used radial cuts to flatten the cornea?

A

radial keratotomy (RK)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the procedure called when you cut & freeze ~300μm layer, reshape it using a lathe, then corneal disc is sutured back onto the eye?

A

keratomileusis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

in radial keratotomy, multiple radial cuts are made where? what does it do?

A

peripheral corneal stroma → relaxes cornea & causing flattening of cornea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

which refractive procedure is used to correct mild to moderate myopia?

A

radial keratotomy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

why is radial keratotomy no longer popular or the safest option?

A
  • corneal integrity is compromised

- instability of refractive results (hyperopic shifts over time & Rx changes w/ diurnal IOP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

which refractive procedure is also known as limbal relaxing incisions & used to correcting astigmatism?

A

arcuate keratotomy (AK)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

in arcuate keratotomy, LRI incisions are made where?

A

at the steeper axis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what procedure uses two PMMA semicircular ring segments designed to be surgically inserted into deep corneal stroma to flatten the central cornea?

A

intacs (aka instrastromal corneal ring segments - ICRS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

intacs correct for what refractive error?

A

mild myopia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

intacs are now used as treatment for what? what does it do?

A

mild to moderate keratoconus → provides structural support for the cone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what refractive procedure uses high frequency radio waves to steepen the cornea?

A

conductive keratoplasty (CK)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

conductive keratotomy corrects what refractive errors?

A

hyperopia, astigmatism, presbyopia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

conductive keratotomy induces what? what does that do?

A

a retraction in corneal collagen cells → steepens central cornea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

conductive keratotomy corrects up to how many diopters of hyperopia?

A

+3.00 D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what uses reactive gases (eg, chlorine & fluorine) when electrically excited to emits UV light which can make very precise minute changes to biological tissue

A

excimer laser (IBM)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what refractive procedure used excimer lasers & was a a precursor to LASIK?

A

photorefractive keratectomy (PRK)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

in PRK, what is applied to the cornea to dissolve the epithelial layer?

A

diluted alchohol solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

in PRK, the excimer laser sculpts which corneal structure to correct refractive error?

A

stromal tissue

25
Q

in PRK, after the laser corrects the refractive error, what is used to protect the eye?

A

antibiotic protective bandage lens is placed over eye

26
Q

what is used in PRK to reduce risk of PRK haze? where is it applied to? what refractive error is it used for?

A

mitomycin-C (MMC) – anti-metabolite

  • applied to stromal bed
  • used in high myopic corrections
27
Q

PRK is indicated for correction of how much myopia? astigmatism? hyperopia?

A

≤ -12.00 D of myopia
≤ -4.00 D of astigmatism
≤ +5.00 D of hyperopia

28
Q

what is considered a stable manifest refraction for PRK?

A

less than or equal to 0.50D change w/in the last 1-2 years

29
Q

is PRK or LASIK recommended for thin corneas?

A

PRK

30
Q

is PRK or LASIK recommended for dry eye patients?

A

PRK

31
Q

is PRK or LASIK recommended for combat/contact sports

A

PRK

32
Q

what refractive procedure can be used for LASIK enhancement?

A

PRK

33
Q

what procedure is used for corneal scars or degenerations such as EBMD?

A

phototherapeutic keratectomy

34
Q

in PRK, how long is the bandage CL left in place?

A

3-7 days

35
Q

when do the “seams” of epithelium meet after PRK?

A

~3rd-4th day

36
Q

when are bandage CLs removed after PRK? what is used to remove it?

A

~3rd-5th day gently with forceps

37
Q

topical steroids are used for how long after PRK? why?

A

~1-3 months

to reduce haze & decrease chance of scar formation in the stroma

38
Q

topical antibiotics are used for how long after PRK?

A

for 1 week

39
Q

what refractive procedure is a combination of microkeratome & excimer laser?

A

LASIK

40
Q

what is the older method of creating flaps in LASIK?

A

microkeratome

41
Q

what is the newer method to create flaps in LASIK?

A

femtosecond laser

42
Q

modern LASIK uses what?

A

both femtosecond & excimer lasers

43
Q

why must use of contact lenses be stopped before LASIK or PRK?

A

CLs will distort the cornea

44
Q

how long do you have to de-adapt with spherical contact lenses?

A

3 days - 1 week

45
Q

how long do you have to de-adapt with toric CLs?

A

1-3 weeks

46
Q

how long do you have to de-adapt with gas permeable contacts?

A

1 month per decade

47
Q

can someone with an uncontrolled systemic or autoimmune condition be a candidate for LASIK/PRK?

A

no

48
Q

can someone with dry eyes that haven’t been treated be a candidate for LASIK/PRK?

A

no

49
Q

if someone has no ocular pathology, are they a good candidate for LASIK/PRK?

A

yes

50
Q

what procedures must be done pre-op for LASIK/PRK?

A
  • cycloplegic refraction

- DFE

51
Q

at least how many microns must be left in the residual stromal bed according to FDA guidelines? most surgeons prefer how many microns? why?

A
  • FDA → at least 250 microns

- surgeons → prefer to stay above 300 to reduce risk of ectasia

52
Q

in cortical cataracts, if the spokes are in the visual axis, what will occur?

A

monocular diplopia

53
Q

in posterior subcapsular cataracts, why are there significant symptoms despite a mild presentation?

A

posterior capsule is an optical nodal point

54
Q

why must you document if a patient is diabetic prior to cataract surgery?

A

diabetics are prone to macular edema

55
Q

why do you have to observe for blepharitis prior to cataract surgery?

A

bacterial infection of S. aureus → don’t want it to cause endophthalmitis

56
Q

why is it important to note any dystrophies or degenerations prior to cataract surgery?

A

RCEs can occur after surgery

57
Q

why is it important to note if there is pseudoexfoliation prior to cataract surgery?

A

iris sphincter won’t work as well → can’t dilate as well (which is what the surgery needs)

58
Q

why do you check for Seidel’s sign post-op for cataract surgery?

A

to check to leakage of aqueous humor in the anterior chamber

Anterior Segment (37 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions