209: Laser Skin Resurfacing: Cosmetic and Medical Applications Flashcards

1
Q

What is the mechanism of action for ablative lasers like CO2 and Er:YAG?

A

Ablative lasers work by absorbing infrared wavelengths by water-containing tissue, leading to tissue vaporization and dermal collagen denaturation, which stimulates neocollagenesis and causes removal of the epidermis and part of the dermis.

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2
Q

What are the key benefits of using fractional photothermolysis in laser resurfacing?

A

Fractional photothermolysis creates small thermal injuries or microscopic treatment zones (MTZs) in the skin while sparing normal healing skin around each MTZ, leading to more rapid healing and reduced recovery time.

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3
Q

How do nonablative laser resurfacing techniques differ from ablative techniques?

A

Nonablative laser resurfacing aims to stimulate dermal neocollagenesis without causing epidermal injury, resulting in fewer side effects and a more favorable postoperative management.

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4
Q

What are the risks associated with the reepithelialization stage after ablative laser resurfacing?

A

During the reepithelialization stage, there is a high risk of complications such as infection, erythema, and swelling, which can lead to permanent skin dyspigmentation and scarring if left unattended.

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5
Q

What are the advantages of using pulsed and scanned CO2 and Er:YAG lasers for skin resurfacing?

A

Pulsed and scanned CO2 and Er:YAG lasers are highly effective for skin resurfacing, resulting in reduced damage to surrounding normal tissue and prolonged postoperative recovery.

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6
Q

What is the primary mechanism of action for ablative laser resurfacing using CO2 or Er:YAG lasers?

A

The primary mechanism involves the absorption of infrared wavelengths by water-containing tissue, leading to tissue vaporization, dermal collagen denaturation, tissue contraction, and stimulation of neocollagenesis.

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7
Q

What is the role of progenitor cells in the healing process after ablative laser resurfacing?

A

Progenitor cells within pilosebaceous units repopulate the epidermis and recruit other cells to aid in wound-healing processes.

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8
Q

How does the healing process differ between fractional photothermolysis and fully ablative laser techniques?

A

Fractional photothermolysis creates microscopic treatment zones (MTZs) with intact skin bridges, leading to rapid healing, while fully ablative techniques lack these intact skin bridges, resulting in slower healing.

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9
Q

What is the gold standard in ablative laser skin resurfacing, and why?

A

The pulsed ablative CO2 laser is considered the gold standard due to its efficacy in treating severe photodamage, rhytides, and laxity.

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10
Q

What is the primary goal of nonablative laser resurfacing?

A

The goal is to stimulate dermal neocollagenesis without inducing epidermal injury or requiring significant postoperative recovery.

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11
Q

What is the mechanism of action for fractional photothermolysis?

A

Fractional photothermolysis creates small thermal injuries or microscopic treatment zones (MTZs) in water-containing skin, sparing normal skin around each MTZ for rapid healing.

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12
Q

What are the advantages of fractional CO2 lasers for treating nonfacial areas?

A

Fractional CO2 lasers can safely treat nonfacial areas like the neck, chest, and dorsal hands due to their ability to reduce recovery time and complications.

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13
Q

What are the advantages of using fractional lasers for nonfacial areas?

A

Fractional lasers reduce recovery time, postoperative discomfort, and complications, making them safer for nonfacial areas like the neck and chest.

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14
Q

What are the key roles of progenitor cells in the healing process after ablative laser resurfacing?

A

Progenitor cells within the pilosebaceous units are crucial for repopulating the epidermis and recruiting other cells to aid in various wound-healing processes.

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15
Q

How does the recovery process differ between ablative and nonablative laser resurfacing?

A

Ablative laser resurfacing typically involves significant postoperative recovery due to the removal of the epidermis and part of the dermis, while nonablative resurfacing aims to stimulate neocollagenesis without significant epidermal injury.

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16
Q

What is the significance of the microscopic epidermal necrotic debris in fractional photothermolysis?

A

Microscopic epidermal necrotic debris is naturally exfoliated within days of treatment, aiding in the healing process and enhancing aesthetic outcomes.

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17
Q

What are the clinical implications of using Er:YAG lasers in skin resurfacing?

A

Er:YAG lasers are effective for skin resurfacing as they provide a balance between efficacy and reduced damage to surrounding normal tissue.

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18
Q

What is the role of treatment zones (MTZs) in fractional resurfacing?

A

MTZs are created by laser-induced small thermal injuries that spare normal skin around each zone, allowing for rapid healing as intact skin bridges the gaps between MTZs.

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19
Q

How do high-energy pulsed CO2 lasers differ from continuous-wave CO2 lasers?

A

High-energy pulsed CO2 lasers allow for higher energy densities to be applied with shorter exposure times, reducing the risk of injury to surrounding tissue.

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20
Q

What are the expected outcomes of nonablative laser resurfacing treatments?

A

Nonablative laser resurfacing typically results in demonstrable changes in dermal collagen with modest clinical improvement, requiring multiple treatments to achieve satisfactory results.

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21
Q

What are the advantages of using Er:YAG lasers in skin resurfacing compared to CO2 lasers?

A

Er:YAG lasers emit light at 2940 nm with a higher water absorption coefficient, making them more efficient in absorbing energy by water-containing tissue.

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22
Q

What are the indications for laser skin resurfacing?

A

Indications include photodamaged skin, atrophic scars, and various epidermal and dermal lesions.

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23
Q

What is the significance of patient selection in laser skin resurfacing?

A

Patient selection is crucial for optimizing clinical outcomes. Ideal candidates include those with fair complexions and photodamaged or scarred facial skin.

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24
Q

What are the benefits of hybrid laser systems in skin resurfacing?

A

Hybrid laser systems simultaneously deliver both ablative Er:YAG and coagulative CO2 laser pulses, resulting in improved hemostasis and enhanced overall treatment efficacy.

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25
Q

What are the postoperative recovery expectations for ablative laser skin resurfacing?

A

Postoperative recovery typically involves 7 to 10 days of intense wound healing during the reepithelialization process.

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26
Q

What are the contraindications for laser skin resurfacing?

A

Contraindications include active skin infections, significant issues with wound healing, and a history of keloid or hypertrophic scar formation.

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27
Q

What preoperative care is recommended for patients undergoing laser skin resurfacing?

A

Use of topical retinoic acid, hydroquinone bleaching agents, or α-hydroxy acids for several weeks before treatment is recommended.

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28
Q

What is the history of keloid or hypertrophic scar formation?

A

A history of keloid or hypertrophic scar formation is a risk factor for similar outcomes after laser skin resurfacing.

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29
Q

What is the history of extensive electrolysis or aggressive chemical peels?

A

A history of extensive electrolysis or aggressive chemical peels may affect the outcomes of laser skin resurfacing.

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30
Q

What preoperative care is recommended for patients undergoing laser skin resurfacing?

A
  1. Use of topical retinoic acid, hydroquinone bleaching agents, or α-hydroxy acids for several weeks before treatment.
  2. Oral antibiotic prophylaxis may be considered due to the risk of bacterial contamination.
  3. Antiviral prophylaxis is recommended for all ablative LSR patients, starting on the day of or prior to treatment and continuing until reepithelialization is complete (7 to 10 days).
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31
Q

What safety precautions should be taken during laser skin resurfacing procedures?

A
  1. Use standard protective health equipment and precautions.
  2. Wear appropriate protective eyewear throughout the procedure.
  3. Utilize a smoke evacuator to protect against inhalation of the ablative laser plume.
  4. Take additional precautions to prevent combustion of oxygen or other flammable substances during the procedure.
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32
Q

What precautions should be taken for patients with Fitzpatrick skin phototype III considering ablative laser skin resurfacing?

A

Patients should be informed about the risk of hypopigmentation or hyperpigmentation, which may be permanent. A spot test on an inconspicuous area is recommended before full-face treatment.

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33
Q

What considerations should be made for patients with a history of isotretinoin therapy considering LSR?

A

A washout period of at least 6 months is often advocated, although newer research shows normal reepithelialization and lack of scar formation during concomitant isotretinoin therapy.

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34
Q

What should be discussed during the consultation for patients with a history of keloid formation considering LSR?

A

Discuss the risk of similar outcomes after LSR and consider alternative treatments.

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35
Q

What are the absolute contraindications for laser skin resurfacing (LSR)?

A

Absolute contraindications include active skin infections (bacterial, viral, or fungal), adnexal abnormalities, recent isotretinoin therapy, history of keloid formation, and extensive electrolysis or aggressive chemical peels.

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36
Q

What are the benefits of using topical tretinoin before LSR?

A

Topical tretinoin accelerates postoperative reepithelialization after dermabrasion and deep chemical peels, but its effects on laser-induced wounds are limited.

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37
Q

What are the risks of treating patients with adnexal abnormalities using LSR?

A

Patients may experience significant postoperative wound healing issues due to impaired progenitor cell function.

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38
Q

What are the expected recovery timelines for patients undergoing ablative fractional resurfacing (AFR)?

A
  1. 2 to 3 days of intense erythema and serosanguinous drainage.
  2. By day 6 or 7, complete reepithelialization and diminution of erythema.
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39
Q

What are the expected outcomes for nonablative laser treatments compared to ablative treatments?

A

Nonablative lasers typically result in mild erythema and edema that spontaneously resolve within 24 hours, while ablative treatments may lead to more intense erythema and longer recovery times.

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40
Q

What role does topical lidocaine play in the anesthesia process for laser skin resurfacing?

A

Topical lidocaine cream is often applied for an hour prior to treatment to enhance tissue hydration and anesthetic penetration before laser irradiation.

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41
Q

How does the history of herpes labialis affect the preoperative care for laser skin resurfacing?

A

Patients with a history of herpes labialis should receive a prophylactic antiviral regimen to prevent reactivation of the virus during or after the procedure.

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42
Q

What is the importance of counseling patients about their expectations prior to laser skin resurfacing?

A

Patients must be counseled adequately to ensure their expectations align with the clinical results that can be reasonably expected from the procedure.

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43
Q

What are the potential complications associated with laser skin resurfacing in patients with a history of extensive electrolysis?

A

Patients may have damaged or absent cutaneous adnexal structures, leading to impaired postoperative healing and unfavorable results.

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44
Q

What are the key components of the technique for laser skin resurfacing?

A
  1. Informed consent
  2. Eye protection
  3. Anesthesia or sedation
  4. Laser treatment initiation
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45
Q

What is the objective of Carbon Dioxide Ablative Laser Skin Resurfacing?

A

The objective is to vaporize unwanted skin lesions as deep as the papillary dermis while minimizing the risk of scarring and permanent pigmentary alteration.

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46
Q

What factors are considered when setting parameters for laser skin resurfacing?

A

Factors include site to be resurfaced, skin phototype of the patient, previous skin treatments administered, and anatomic location.

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47
Q

What are the advantages of using Er:YAG Ablative Laser Skin Resurfacing?

A

Advantages include improved absorption coefficient, minimal collateral thermal damage, very little thermal tissue necrosis, and fewer passes required to achieve similar depths of penetration compared to CO2 lasers.

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48
Q

What is the typical clinical improvement percentage after Nonablative Laser Skin Resurfacing?

A

Clinical improvement typically averages 30% to 50% after a series of 3 or more monthly sessions.

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49
Q

What are the postoperative care instructions for patients after laser skin resurfacing?

A

Postoperative care instructions include proper wound care, maintaining a moist environment, using either an open or closed wound dressing technique, and applying ice packs and anti-inflammatory medications as needed.

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50
Q

What are the greatest advantages associated with CO2 Laser Skin Resurfacing?

A

The greatest advantages include excellent tissue contraction, hemostasis, prolonged neocollagenesis, and collagen remodeling.

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51
Q

How should laser settings be adjusted for thinner periorbital skin?

A

Thinner skin requires fewer laser passes compared to thicker facial skin to minimize the risk of scarring and pigmentary alterations.

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52
Q

What steps should be taken during a multipass CO2 LSR procedure to minimize excessive thermal injury?

A

Partially desiccated tissue should be removed manually with wet gauze after each pass to expose the underlying dermis.

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53
Q

What are the advantages of using a minimally traumatic single-pass CO2 LSR procedure compared to a multipass technique?

A

Single-pass CO2 LSR results in faster postoperative reepithelialization, an improved side-effect profile, and reduced thermal and mechanical trauma.

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54
Q

What is the recommended postoperative care for partial-thickness cutaneous wounds after LSR?

A

Wounds should be maintained in a moist environment to promote efficient healing and reduce the risk of scarring.

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55
Q

What are the postoperative benefits of using a closed wound dressing technique?

A

Closed wound dressings decrease postoperative pain, erythema, and edema, increase the rate of reepithelialization, and require less patient effort in wound care.

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56
Q

What are the risks of using high-overlap settings on a scanning device during CO2 LSR?

A

High-overlap settings can lead to excessive thermal injury, increasing the risk of scarring.

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57
Q

What are the postoperative care recommendations for patients undergoing fully ablative LSR?

A

Recommendations include maintaining a moist wound environment, using pain medications, and applying ice packs and anti-inflammatory medications.

58
Q

What are the advantages of using Er:YAG lasers over CO2 lasers?

A

Er:YAG lasers produce minimal collateral thermal damage, shorter postoperative recovery, and less thermal tissue necrosis.

59
Q

What are the key factors to consider when setting parameters for Carbon Dioxide Ablative Laser Skin Resurfacing?

A

Key factors include site to be resurfaced, skin phototype of the patient, and previous skin treatments administered.

60
Q

What is the primary objective of ablative laser skin resurfacing?

A

To vaporize unwanted skin lesions as deep as the papillary dermis while minimizing the risk of scarring.

61
Q

How does the depth of ablation correlate with the number of passes in laser skin resurfacing?

A

The depth of ablation correlates directly with the number of passes performed; more passes generally lead to deeper ablation.

62
Q

What is the recommended approach to avoid excessive thermal injury during multipass laser skin resurfacing?

A

To reduce the risk of excessive thermal injury, partially desiccated tissue should be removed manually with wet gauze after each pass.

63
Q

What are the advantages of using minimally traumatic single-pass CO2 laser procedures?

A

Advantages include faster postoperative reepithelialization, improved side-effect profile, and the lased skin serving as a biologic wound dressing.

64
Q

What is the typical energy range for short-pulsed Er:YAG laser treatments?

A

The energy range typically falls between 5 to 15 J/cm².

65
Q

How does the number of passes required for Er:YAG laser compare to CO2 laser for similar treatment depths?

A

It takes 3-4 times as many Er:YAG passes to achieve similar depths of penetration as the CO2 laser.

66
Q

What are the clinical outcomes associated with ablative fractional laser systems?

A

Ablative fractional laser systems typically require only 1 treatment to achieve patient satisfaction.

67
Q

What is the expected clinical improvement from nonablative laser skin resurfacing after a series of treatments?

A

Clinical improvement typically averages 30% to 50% after a series of 3 or more monthly sessions.

68
Q

What are the advantages of using a closed dressing technique postoperatively?

A

Advantages include increased patient comfort, reduced erythema and edema, increased rate of reepithelialization, and decreased requirement for patient effort in wound care.

69
Q

What are the greatest advantages associated with CO2 laser skin resurfacing?

A

Greatest advantages include excellent tissue contraction, hemostasis, prolonged neocollagenesis, and collagen remodeling.

70
Q

What is the significance of the ‘stacking’ technique in laser skin resurfacing?

A

The ‘stacking’ technique can lead to excessive thermal injury and increased risk of scarring, and should be avoided.

71
Q

What is the role of postoperative ice pack application?

A

Ice pack application helps to reduce swelling and discomfort during the initial recovery period.

72
Q

What is the recommended treatment approach for deep dermal lesions with extensive photodamage using Er:YAG and CO2 lasers?

A

For deep dermal lesions: Short-pulsed Er:YAG laser: 9 or 10 passes; CO2 laser: 2 or 3 passes.

73
Q

What factors influence the clinical effect of nonablative laser skin resurfacing?

A

Factors include energy delivered and density (area of coverage).

74
Q

What are the potential risks associated with postoperative care following ablative laser resurfacing?

A

Potential risks include infection, additional expense for wound care, and increased discomfort.

75
Q

What is the impact of skin phototype on the treatment parameters for laser skin resurfacing?

A

Skin phototype influences the selection of treatment parameters to minimize risks.

76
Q

How does the treatment of periocular skin differ from other areas in terms of laser settings?

A

Treatment of periocular skin requires a decrease in both energy and coverage density.

77
Q

What is the importance of informed consent in laser skin resurfacing procedures?

A

Informed consent ensures that the patient understands the risks, benefits, and expected outcomes.

78
Q

What are the common side effects associated with ablative laser skin resurfacing?

A

Common side effects include pain, erythema, and postoperative dyspigmentation.

79
Q

What is the significance of using a biologic wound dressing after laser treatment?

A

It helps in protecting the area, promoting healing, and reducing unnecessary trauma.

80
Q

What are the common side effects associated with ablative laser skin resurfacing?

A

Common side effects include pain, erythema, and postoperative dyspigmentation. These effects can vary based on the type of laser and treatment depth.

81
Q

What is the significance of using a biologic wound dressing after laser treatment?

A

Using a biologic wound dressing allows the lased skin to remain intact, which helps in protecting the area, promoting healing, and reducing unnecessary thermal and mechanical trauma to less-involved skin.

82
Q

What is the expected improvement in atrophic acne scars after nonablative laser treatments?

A

Nonablative laser treatments can lead to 50% and higher improvement in atrophic acne scars, particularly after a series of treatments.

83
Q

What are the clinical implications of using modified Er:YAG laser systems?

A

Modified Er:YAG laser systems improve hemostasis, enhance visualization of the treatment area, and provide added thermal effects on the tissue, generally delivered as single treatments with clinical outcomes similar to CO2 lasers.

84
Q

What is the recommended approach for treating large pores and hypertrophic scars?

A

To improve the appearance of large pores and hypertrophic scars, a series of fractionated laser treatments can be employed, often resulting in significant clinical improvement.

85
Q

What is the role of anti-inflammatory medications in postoperative care?

A

Anti-inflammatory medications are important in postoperative care to help manage pain and inflammation during the recovery period after laser skin resurfacing.

86
Q

How does the technique of laser treatment minimize excessive thermal damage?

A

Meticulous laser technique with nonoverlapping scans minimizes excessive thermal damage to the skin, ensuring safer and more effective treatment outcomes.

87
Q

What is the expected timeline for reappraisal of photodamage after ablative fractional laser treatment?

A

Reappraisal of photodamage, rhytides, or scarring can be performed 6 to 12 months postoperatively to assess if additional treatments are clinically warranted.

88
Q

What are the disadvantages of using a closed dressing technique postoperatively?

A

Disadvantages of a closed dressing technique include additional expense and an increased risk of infection due to the occlusive nature of the dressing.

89
Q

What is the significance of the energy delivered in nonablative laser treatments?

A

The energy delivered in nonablative laser treatments is directly proportional to the depth of dermal penetration and the overall tissue effect, impacting the clinical outcomes.

90
Q

What histological changes occur in CO2 laser-treated skin?

A
  • Replacement of epidermal cellular atypia and dysplasia with normal, healthy epidermal cells from adjacent follicular adnexal structure.
  • In the papillary dermis, coagulation of disorganized masses of actinically-induced elastotic material is replaced with normal compact collagen bundles arranged in parallel to the skin’s surface.
  • Normal inflammatory response includes granulation tissue formation, neovascularization, and increased recruitment of macrophages and fibroblasts.
91
Q

What are the common postoperative reactions following ablative CO2 laser resurfacing?

A
  • Erythema and edema are expected in the immediate postoperative period and are not considered adverse events.
  • The degree of erythema correlates with the depth of ablation and the number of laser passes.
  • Postoperative erythema averages:
    • Single-pass CO2 laser: 4.5 weeks
    • Long-pulsed Er:YAG laser: 3.6 weeks
  • Erythema and edema may be aggravated by underlying rosacea or dermatitis but most resolve spontaneously.
92
Q

What factors influence the side effects and complications of laser skin resurfacing?

A
  • Expertise of the operator
  • Anatomic location treated
  • Skin phototype of the patient
  • Underlying skin conditions
  • Aggressiveness of the laser procedure
  • Postoperative wound care
  • Several other variables, including those listed in Table 209-4.
93
Q

What is the average time to reepithelialization for single-pass CO2 and long-pulsed Er:YAG laser resurfacing?

A

Laser Type | Average Time to Reepithelialization |
|————|————————————-|
| Single-pass CO2 | 5.5 days |
| Long-pulsed Er:YAG | 5.1 days |

94
Q

What are some minor side effects of ablative laser skin resurfacing?

A
  • Milia formation: exacerbated by the use of occlusive dressings; resolves spontaneously.
  • Contact dermatitis: can be irritant or allergic, often due to topical medications.
  • Hyperpigmentation: more common in patients with darker skin tones; generally transient but can be hastened by topical agents.
  • Hypopigmentation: often not observed for several months; incidence is markedly lower with fractionated lasers.
95
Q

What are the histologic changes observed in CO2 laser-treated skin?

A

Histologic changes include replacement of epidermal cellular atypia with normal cells, coagulation of elastotic material in the papillary dermis, and formation of granulation tissue with neovascularization.

96
Q

What are the common postoperative reactions to ablative LSR, and how can they be managed?

A

Common reactions include erythema, edema, milia formation, and acne flares. Management includes avoiding irritating topicals, using oral antibiotics for acne, and applying topical ascorbic acid.

97
Q

What are the clinical outcomes of using fractional CO2 lasers for acne scarring?

A

Fractional CO2 lasers show significant (50% to 75%) improvement in scar depth after 2 or 3 treatments, with better results for higher energies and density coverage.

98
Q

What are the histologic effects of thermal injury caused by CO2 laser irradiation?

A

Thermal injury causes collagen fiber contraction, disruption of interpeptide bonds, and conformational changes in collagen’s triple-helical structure, leading to neocollagenesis.

99
Q

What are the advantages of using light-emitting diode (LED) photomodulation after LSR?

A

LED photomodulation improves post-laser erythema and accelerates recovery.

100
Q

What are the potential side effects of ablative LSR in patients with darker skin tones?

A

Side effects include hyperpigmentation, which is generally transient, and hypopigmentation, which may be permanent.

101
Q

What histological changes occur in CO2 laser-treated skin compared to untreated skin?

A
  • Replacement of epidermal cellular atypia and dysplasia with normal, healthy epidermal cells from adjacent follicular adnexal structure.
  • In the papillary dermis, coagulation of disorganized masses of actinically-induced elastotic material is replaced with normal compact collagen bundles arranged in parallel to the skin’s surface.
  • Normal inflammatory response includes granulation tissue formation, neovascularization, and increased recruitment of macrophages and fibroblasts.
102
Q

What are the expected postoperative reactions following ablative CO2 laser resurfacing?

A
  • Erythema and edema are expected in the immediate postoperative period and are not considered adverse events.
  • The degree of erythema correlates with the depth of ablation and the number of laser passes.
  • Postoperative erythema averages:
    • Single-pass CO2 laser: 4.5 weeks
    • Long-pulsed Er:YAG laser: 3.6 weeks
  • Erythema and edema may be aggravated by underlying rosacea or dermatitis but most resolve spontaneously.
103
Q

How does the healing time compare between single-pass CO2 and long-pulsed Er:YAG laser resurfacing?

A
  • Average time to reepithelialization:
    • Single-pass CO2: 5.5 days
    • Long-pulsed Er:YAG laser resurfacing: 5.1 days
  • Postoperative healing times and complication profiles are comparable, even in patients with darker skin phototypes.
104
Q

What factors influence the degree of collagen shrinkage and dermal remodeling after laser treatment?

A
  • Thermal effects: Collagen fiber contraction occurs through disruption of interpeptide bonds at temperatures ranging from 55°C to 62°C.
  • Fibroblast activity: Migration into laser wounds may upregulate the expression of immune-modulating factors, enhancing collagen shrinkage and ongoing neocollagenesis.
  • The aggressiveness of the laser procedure and the skin phototype of the patient also play significant roles.
105
Q

What are the minor side effects associated with ablative laser skin resurfacing?

A
  • Milia formation: Worsening of acne, exacerbated by occlusive dressings and ointments, resolves spontaneously.
  • Contact dermatitis: Can be irritant or allergic, developing in response to topical medications and moisturizers.
  • Hyperpigmentation: More common in patients with darker skin tones, generally transient but can be hastened by topical agents.
  • Hypopigmentation: Often not observed for several months, incidence is markedly reduced with fractionated lasers.
106
Q

What is the clinical significance of persistent collagen shrinkage after ablative CO2 laser resurfacing?

A
  • Persistent collagen shrinkage contributes to the continued clinical benefits observed after treatment, enhancing skin tone and wrinkle severity.
  • This effect is influenced by several factors, including the depth of ablation and the number of laser passes used during the procedure.
107
Q

What postoperative care instructions should be given to patients after laser resurfacing?

A
  • Avoid potentially irritating topicals such as retinoic acid derivatives and glycolic acid until substantial reepithelialization has occurred.
  • Use topical ascorbic acid after reepithelialization to reduce cutaneous inflammation.
  • Daily sunscreen is essential to prevent further skin darkening during the healing process.
108
Q

How does the use of higher laser energies affect clinical outcomes in laser resurfacing?

A
  • Higher energies and density coverage tend to yield better clinical outcomes in terms of improvement in rhytides and atrophic scars.
  • However, this may also result in longer postoperative recovery times, necessitating careful patient selection and management.
109
Q

What role do fibroblasts play in the healing process after laser skin resurfacing?

A
  • Fibroblasts migrate into laser wounds and may upregulate the expression of immune-modulating factors, which serve to enhance collagen shrinkage and ongoing neocollagenesis, contributing to the overall healing and remodeling process.
110
Q

What is the expected duration of erythema following long-pulsed Er:YAG laser treatment?

A
  • The average duration of postoperative erythema following long-pulsed Er:YAG laser treatment is approximately 3.6 weeks.
111
Q

What is the most common infection following ablative laser resurfacing and how should it be treated?

A

The most common infection is reactivation of labial HSV infection. It should be treated aggressively to prevent dissemination or scarring, using oral antiviral agents such as acyclovir, famciclovir, and valacyclovir. In severe cases, IV therapy may be required, and practitioners often advocate for oral prophylaxis during the postoperative period until reepithelialization is complete (7 to 10 days).

112
Q

What are the most severe complications associated with ablative cutaneous laser resurfacing?

A

The most severe complications are: 1) hypertrophic scarring 2) ectropion. Hypertrophic scarring is associated with excessive thermal injury and can occur due to inadvertent pulse stacking or incomplete removal of desiccated tissue. Ectropion is rarely seen but may require surgical correction if encountered.

113
Q

What are the main advantages of ablative fractional lasers compared to fully ablative laser skin resurfacing techniques?

A

The main advantages of ablative fractional lasers include:

  1. Excellent side-effect profiles
  2. Low incidence of complications

Postoperative recovery is quicker and more predictable, with intense erythema and crusting lasting for 3 to 6 days, and moderate erythema lasting days to weeks, in contrast to months of erythema after traditional ablative LSR.

114
Q

What is the significance of pilosebaceous units in relation to ablative laser resurfacing?

A

Areas with a relative paucity of pilosebaceous units, such as the eyelids, neck, and chest, are at a higher risk for hypertrophic scarring and excessive thermal injury during ablative laser resurfacing. Care must be taken when treating these areas to avoid complications.

115
Q

What future developments are being explored with ablative lasers?

A

Future developments with ablative lasers include:

  • Creating microscopic vertical holes through the epidermis to stimulate physiologic effects for antiaging.
  • Serving as channels for topically applied drugs to gain access to the dermis.
  • Investigating the dermal penetration of various drugs when applied to laser-treated skin.
  • Evaluating AFR-assisted drug delivery for dermatologic therapy, focusing on drug-specific channel density and depth parameters.
116
Q

A patient undergoing ablative fractional laser resurfacing (AFR) reports intense erythema lasting for weeks. What factors could contribute to this prolonged erythema?

A

Post-AFR erythema may resolve slower in patients with skin phototype I or II and in those who underwent more aggressive treatments.

117
Q

What are the main advantages of ablative fractional lasers compared to fully ablative LSR techniques?

A

Ablative fractional lasers have excellent side-effect profiles, low complication rates, quicker and more predictable recovery, and a lower risk of scarring and dyspigmentation.

118
Q

A patient with Fitzpatrick skin phototype I undergoes AFR. What postoperative reaction is expected, and how long might it last?

A

Intense erythema and crusting may last for 3 to 6 days, with moderate erythema persisting for days to weeks.

119
Q

What are the potential complications of treating areas with a paucity of pilosebaceous units using ablative fractional lasers?

A

Excessive thermal injury in areas like the eyelids, neck, and chest can lead to hypertrophic scarring. Proper technique is essential to minimize this risk.

120
Q

What is the role of ablative fractional lasers in drug delivery?

A

Ablative fractional lasers create microscopic vertical holes in the epidermis, allowing topically applied drugs to penetrate the dermis more effectively.

121
Q

What are the advantages of using ablative fractional lasers for antiaging treatments?

A

Ablative fractional lasers stimulate physiologic effects responsible for antiaging and create channels for enhanced drug delivery.

122
Q

What are the benefits of using ablative fractional lasers for treating pigmented lesions?

A

Ablative fractional lasers amplify clinical results and shorten recovery times when combined with other laser technologies.

123
Q

What are the potential complications of inadvertent pulse stacking during LSR?

A

Inadvertent pulse stacking can lead to excessive thermal injury, increasing the risk of scarring and fibrosis.

124
Q

What is the most common infection following ablative laser resurfacing and how should it be treated?

A

The most common infection is reactivation of labial HSV infection, which should be treated aggressively with oral antiviral agents such as acyclovir, famciclovir, and valacyclovir. IV therapy may be required in severe cases, and oral prophylaxis is recommended during the postoperative period until reepithelialization is complete (7 to 10 days).

125
Q

What are the main advantages of ablative fractional lasers compared to fully ablative laser skin resurfacing techniques?

A

The main advantages of ablative fractional lasers include:

  1. Excellent side-effect profiles
  2. Low incidence of complications

Postoperative recovery is quicker and more predictable, with intense erythema and crusting lasting for 3 to 6 days postoperatively, and moderate erythema lasting days to weeks.

126
Q

What is the risk associated with excessive thermal injury during ablative laser resurfacing, and how can it be mitigated?

A

Excessive thermal injury can lead to hypertrophic scarring. This risk can be mitigated by avoiding inadvertent pulse stacking or scan overlapping, ensuring complete removal of desiccated tissue between laser passes, and using proper technique during the procedure.

127
Q

What is ectropion and what factors increase its risk following ablative laser resurfacing?

A

Ectropion is the most severe complication associated with ablative cutaneous laser resurfacing, particularly of the lower eyelid. The risk is increased in patients who have had previous lower blepharoplasty or other surgical manipulation of the periorbital region.

128
Q

What can excessive thermal injury lead to?

A

Excessive thermal injury can lead to hypertrophic scarring.

129
Q

How can the risk of hypertrophic scarring be mitigated?

A

The risk can be mitigated by avoiding inadvertent pulse stacking or scan overlapping, ensuring complete removal of desiccated tissue between laser passes, and using proper technique during the procedure.

130
Q

What is ectropion?

A

Ectropion is the most severe complication associated with ablative cutaneous laser resurfacing, particularly of the lower eyelid.

131
Q

What factors increase the risk of ectropion following ablative laser resurfacing?

A

The risk is increased in patients who have had previous lower blepharoplasty or other surgical manipulation of the periorbital region.

132
Q

Why is preoperative examination essential before ablative laser resurfacing?

A

Preoperative examination is essential to assess eyelid laxity and skin elasticity.

133
Q

What areas require special care during ablative laser resurfacing?

A

The areas with a relative paucity of pilosebaceous glands include the eyelids, neck, and chest.

134
Q

What is the role of ablative fractional lasers in drug delivery?

A

Ablative fractional lasers create microscopic vertical holes through the epidermis, stimulating physiologic effects responsible for antiaging and serving as channels for topically applied drugs to gain access to the dermis.

135
Q

What is the benefit of using ablative fractional lasers for drug penetration?

A

This enhances the penetration of various drugs, improving their efficacy in dermatologic treatments.

136
Q

What postoperative care is recommended after ablative fractional laser resurfacing?

A

Postoperative care includes monitoring for pinpoint bleeding and serosanguinous discharge, which typically resolves within 24 to 48 hours.

137
Q

What symptoms may patients experience postoperatively?

A

Patients may experience intense erythema and crusting for 3 to 6 days, and moderate erythema may last days to weeks.

138
Q

What is the significance of performing a full skin examination before ablative laser resurfacing?

A

Performing a full skin examination is imperative to identify any pre-existing conditions and to obtain a complete medical and family history.

139
Q

What are potential treatments for hypertrophic scarring?

A

Potential treatments include the application of potent topical corticosteroids and the use of pulsed-dye lasers.

140
Q

What factors should be considered during the preoperative examination?

A

Factors to consider include eyelid laxity, skin elasticity, and the patient’s history of previous surgical procedures in the periorbital region.