Brainscape's Knowledge GenomeTM

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


See full index

Lasers > XM 1 > Flashcards

XM 1 Flashcards

1
Q

What are the 3 types of effects that occur as a result of use of therapeutic lasers?

A
  1. Thermal effects
  2. Ionization effects
  3. Photochemical effects
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What FDA class of lasers are the lasers used for eye procedures?

A

Class IV

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

What FDA class of lasers are those used in printers, CD players, and DVD players?

A

Class I

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

What FDA class of lasers are those used in barcode scanners?

A

Class II

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

What FDA class of lasers are pointers?

A

Class III

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

Starting with which FDA class of lasers are immediate skin and eye injury possible?

A

Class III

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

What is considered the “safe” limit of laser power?

A

5 mW

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

Interactions of light on biological tissue depend on what 3 characteristics?

A
  1. Wavelength
  2. Pulse duration
  3. Irradiance (power per unit area)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the end result of photocoagulation caused by laser light?

A

Denatured proteins

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

What rise in temperature will cause photocoagulation of tissue?

A

10-20 degrees Celsius

(results in tissue temperature between 50 and 60 C

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

What effect of therapeutic lasers is associated with the “thunderclap” and results in tissue damage?

A

Photodisruption (Ionizing Effect)

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

What temperature range does photovaporization occur in?

A

60-100 degrees Celsius

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

What temperature range does photodisruption occur in?

A

100-305 degrees Celsius

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

What are 2 examples of thermal effects?

A
  1. Photocoagulation

2. Photovaporization

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

What is 1 examples of an ionization effect?

A

Photodisruption

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

What are 2 examples of photochemical effects?q

A
  1. Photoradiation

2. Photoablation

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

What are 6 modes of laser operation?

A
  1. Continuous wave (CW) lasers
  2. Pulsed lasers
  3. Q-switched lasers
  4. Mode-locked lasers
  5. Fundamental systems
  6. Multimode systems
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

At what temperature do visual changes begin occurring in the retina?

A

60 degrees Celsius

Blanching begins to occur due to coagulation

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

At what temperature does a smoke plume result in the retina?

A

100 degrees Celsius

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

What is PDT?

A

Photodynamic Therapy

Same thing as photoradiation

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

What does photoablation do in layman’s terms?

A

Vaporizes the tissue by breaking bonds that bind the tissue together

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

What are 2 examples of lasers that interact with photothermal effects?

A
  1. Argon laser

2. Nd: YAG Laser

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

What is 1 example of a laser that interacts with photoablation?

A

Excimer laser

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

What is 1 example of a laser that interacts via photoradiation?

A

Photodynamic therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is 1 example of a laser that interacts with tissue via photodisruption?

A

Nd: YAG laser (Q-Switched)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are 3 methods of laser delivery?

A
  1. Biomicroscope (Slit Lamp)
  2. Binocular Indirect Ophthalmoscope (BIO)
  3. Endophotocoagulation (enter through pars plana)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is an argon blue-green laser composed of?

A

70% blue (488 nm)

30% green (514 nm)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the wavelength of a green argon laser?

A

514.5 nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the wavelength of an Nd-YAG laser?

A

532 nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the wavelength of a yellow laser?

A

577 nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the wavelength of a krypton red laser?

A

647 nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the wavelength of a diode laser?

A

805-810 nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is a large benefit of the MicroPulse laser design?

A

Long off times allow tissue to cool which results in less thermal damage to the retina

34
Q

What does duty cycle mean as applied to MicroPulse lasers?

A

Example: 5% duty cycle

On for 5 units of time, off for 95 units of time

35
Q

What is a major advantage of the green argon laser?

A

No absorption by macular pigment

36
Q

What laser is preferred over green argon lasers to treat choroidal neovascularization?

A

Yellow argon laser

37
Q

What are the 10 layers of the retina from inner (vitreous) to outer (choroid)?

A
  1. (ILM) Internal limiting membrane
  2. (NFL) Nerve fiber layer
  3. (GCL) Ganglion cell layer
  4. (IPL) Inner plexiform layer
  5. (INL) Inner nuclear layer
  6. (OPL) Outer plexiform layer
  7. (ONL) Outer nuclear layer
  8. (ELM) External limiting membrane
  9. (PR) Photoreceptors
  10. (RPE) Retinal pigmented epithelium
38
Q

What membrane lies directly outside of the RPE?

A

Bruch’s membrane

39
Q

For the laser to remain effective, an increase in spot size needs an increase in what?

A

Increase in power

40
Q

What are the 2 types of laser delivery system?

A
  1. Parfocal system

2. Defocus system

41
Q

Where will a parfocal system be focused for treatment?

A

On the retina

42
Q

As parfocal spot size increases, does the diameter of the laser at the cornea increase or decrease?

A

Decreases

More risk of damage

43
Q

Where will a defocus system be focused for treatment?

A

On the retina or behind the retina

44
Q

What would occur if a defocus system was focused in front of the retina?

A

Vitreous damage or lens damage

45
Q

What is an advantage to the defocus system and when would it be utilized?

A

Corneal beam density decreases as spot size increases (Lower risk of damage)
Useful for when large spot size is required

46
Q

What is the scale of photocoagulation lesions graded as? Which is most mild? Most severe?

A

1-4
1 is most mild (light, minimal constriction)
4 is most severe (heavy, total constriction, charring)

47
Q

How are punctate and streaked coagulation patterns different?

A

Punctate style patterns appear as dots

Streaked style patterns appear as dashes

48
Q

What is the anatomic center of the fovea known as?

A

Umbo

49
Q

What is the molecule that causes neovascularization in diabetic retinopathy?

A

VEGF

50
Q

What is the name of the laser treatment for diabetic retinopathy?

A

Panretinal Photocoagulation

51
Q

What do black spots in the retina after laser treatment signal?

A

RPE has been damaged

52
Q

What is peripheral laser iridotomy used to treat?

A

Either primary or secondary angle closure glaucoma

53
Q

What 2 types of lasers are useful for performing Peripheral Laser Iridotomy procedures?

A
  1. Argon lasers

2. Nd: YAG lasers

54
Q

What type of laser is used to perform PRP?

A

Argon Green

PASCAL (Pattern Scanning Laser)

55
Q

What is the purpose of the PLI procedure?

A

Creates an opening in the peripheral iris to allow aqueous to pass through

56
Q

Where is the opening in the iris typically made in peripheral laser iridotomy?

A

Underneath the upper lid

57
Q

What is the purpose of laser trabeculoplasty?

A

To treat the trabecular meshwork to improve the outflow of aqueous

58
Q

What are the 4 types of laser trabeculoplasty?

A
  1. (ALT) Argon Laser Trabeculoplasty
  2. (SLT) Selective Laser Trabeculoplasty
  3. (MLT) Micropulse Laser Trabeculoplasty
  4. (TSLT) Titanium Sapphire Laser Trabeculoplasty
59
Q

Which type of laser trabeculoplasty is not commonly used anymore because of trabecular meshwork damage?

A

Argon Laser Trabeculoplasty (ALT)

60
Q

When is laser trabeculoplasty typically performed?

A

As a last resort, once patient is on maximum medical therapy.

61
Q

What is the purpose of ALT?

A

To scar the trabecular meshwork to increase the amount of aqueous outflow

62
Q

Where is the ALT laser aimed, and how many degrees around is the first treatment?

A

Junction of pigmented and nonpigmented TM

180 degrees

63
Q

What is the target and goal of SLT treatment?

A

Targets melanin in pigmented TM

Recruits macrophages to help with outflow

64
Q

Does previous ALT treatment have any effects on the results of SLT treatment?

A

No

IOP reduction is not influenced by previous ALT

65
Q

How long after SLT do the biochemical changes take place?

A

4-6 weeks

Delayed response

66
Q

What is the main goal of MLT?

A

Simulate a biological response in the TM while minimizing damage to the tissue

67
Q

Between ALT, SLT, and MLT, which procedure involves the smallest laser spot size?

A

ALT

About 50 microns

68
Q

How does the spot size of MLT compare to that of SLT?

A

Slightly smaller
300 microns as opposed to 400 microns
Allows access to narrower angles

69
Q

Is ALT a repeatable procedure?

A

No

70
Q

Are MLT and SLT repeatable procedures?

A

Yes

71
Q

Where is the laser focused in a YAG laser capsulotomy?

A

Slightly behind the lens in the vitreous

72
Q

What is the purpose of YAG laser capsulotomy

A

Opens the opacified posterior capsule to improve patient VA and allow easier viewing of the fundus

73
Q

Is an IOP spike normal to see following YAG laser capsulotomy?

A

Yes

74
Q

What is the normal size of the opening of the posterior capsule created in YAG laser capsulotomy?

A

4mm

75
Q

What is the average number of laser spots per eye in panretinal photocoagulation?

A

1200 laser spots per eye

76
Q

Topical anesthesia allows for the delivery of about how many laser spots with PRP?

A

500-600 spots

77
Q

What type of anesthesia allows for the delivery of a full treatment (1200) of laser spots in PRP?

A

Retrobulbar anesthesia

78
Q

What is the purpose of PRP?

A

Kill/destroy living retina that is releasing VEGF due to being in a hypoxic state

79
Q

How far around the posterior pole (macula and optic disc) are the laser spots delivered with PRP?

A

3 disc diameters around posterior pole and extend to the equator

80
Q

What is the purpose of lasering around a retinal break?

A

Seals off the progression of sub-retinal fluid (SRF) that would lead to macular involvement

81
Q

What is a risk of laser treatment of retinal tears?

A

Vitreous shrinkage may tear the retina farther

Shrinkage may occur with opacities present

Lasers (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions