State of the Art
Die Guidlines des DLB entsprechen denjenigen der American Academy of Dermatology (AAD). Dadurch ist gewaehrleistet, dass die Behandlungen am Laserzentrum nach dem neusesten Stand des Wissens durchgeführt werden. Derzeit liegt die deutsche Uebersetzung leider noch nicht vor. Für einzelne Fragepunkte wollen Sie bitte die untenstehenden Hyperlinks anklicken. Literatur findet sich am Schluss de Dokumentes reichlich. Für weitere Informationen bezüglich Laser siehe auch Laserskinresurfacing.
Guidelines of Care for Laser Surgery (following the Guidlines of the AAD)
- Continuous wave carbon dioxide (CO2) laser
- Copper vapor
- Diagnostic Criteria
- Definition
- Erbium: Yttrium Aluminum Garnet
- Flash lamp pumped pulsed light sources
- Flash lamp-pumped pulsed dye laser
- Introduction
- Krypton laser
- Long pulsed alexandrite laser
- Equipment
- Nd:YAG laser
- Physician qualifications
- Postoperative findings
- Preoperative
- Pulsed and scanned CO2 laser
- Pulsed dye laser (510 nm)
- Pulsed KTP lase
- Q-switched alexandrite laser
- Q-switched ruby laser
- Treatment techniques
Task Force: Jeffrey S. Dover, M.D., Chairman, Kenneth A. Arndt, M.D., Scott M. Dinehart, M.D., Richard E. Fitzpatrick, M.D., Ernesto Gonzalez, M.D.
1. Introduction
The American Academy of Dermatology's Committee on Guidelines of Care is developing guidelines of care for our profession. The development of guidelines will promote the continued delivery of quality care and assist those outside our profession in understanding the complexities and scope of care provided by dermatologists. For the benefit of members of the American Academy of Dermatology who practice outside the jurisdiction of the United States, the listed devices may include indications that are not currently approved by the U.S. Food and Drug Administration for the particular type of laser.
2. Definition
Lasers (Light Amplification by the Stimulated Emission of Radiation) are sources of high-intensity, monochromatic light that can be advantageously employed in the treatment of a variety of dermatologic diseases depending on the wavelength, the pulse characteristics, and the true irradiance of the laser being used and the nature of the clinical condition being treated. in addition, high intensity incoherent and multi-chromatic pulsed light may be used with the same principles of selective targeting by proper choice of wavelength spectrum, pulse characterization, and fluence.
3. Rationale
3.1.
Scope
Laser surgery is a rapidly changing field in which new types of lasers,
as well as the conditions amenable to treatment, are continually being
introduced. The conditions listed below have been treated using the
particular laser or group of lasers by different physicians with varying
results. This guideline reflects the best information available at
the time the report was prepared.
3.1.1. Visible light lasers emitting continuous
wave radiation and
recognized by the skin
Lasers in this group include the continuous wave and quasi-continuous wave
visible light lasers, which are the argon laser (488-514 nm); the continuous
wave dye laser, usually tuned between 585-600 nm; the copper vapor laser
(511-578 nm); the continuous wave potassium titanyl phosphate (KTP) lasers
(532 nm); and the krypton laser (521, 530 and 568 nm). All these lasers
produce continuous or shuttered visible laser light, in general, laser
wavelengths from 532 to 595 nin are used predominantly in the treatment
of vascular disorders, while wavelengths from 488 to as high as 532 are
used in the treatment of benign pigmented disorders. With all these continuous
and quasi-continuous devices the ability to confine spatially thermal damage
is difficult. Thus, unlike treatment with the pulsed dye and pulsed KTP
laser, the final outcome is highly dependent on the skill of the laser
operator. Computer-driven mechanical scanning devices have been developed
to ensure more uniformity of treatment and to help contain the thermal
injury spatially, thus reducing the risk of using these continuous and
quasi-continuous lasers.
3.1.1.1. Argon laser
and continuous wave argon-pumped dye laser
The argon laser produces visible light at 6 wavelengths between 488 and 514 nm. in the continuous wave argonpumped tunable dye laser an argon laser is coupled to a dye cavity to produce visible laser light of differing wavelengths depending on the type of dye placed in the laser cavity. The dyes that are used absorb strongly in various portions of the physical spectrum to produce colored light. By choosing the appropriate dye, it is possible to produce a desired wavelength or color of laser light. Dye lasers employed for the treatment of cutaneous vascular disorders use rhodamine dye having a peak emission at or near 577 nm, Fine tuning can be achieved by using a prism to increase or decrease the emitted wavelength by up to 20 nm.
3.1.1.2. Copper
vapor lasers
Copper vapor lasers produce either yellow light at 578 nm or green
light at 511 nm by heating elemental copper or copper salts in the
optical cavity. The energy is released as a chain of lowenergy short
20-40 ns pulses at a frequency of 10-15 kHz. This chain can be electronically
shuttered to produce bursts of pulses of 0.075-0.3 seconds in duration.
3.1.1.3. Krypton
laser
The krypton laser is a gas-medium laser that emits either yellow
light at a wavelength of 568 nm to treat vascular lesions, or green
light at wavelengths of 521 and 530 nm to treat pigmented lesions.
3.1.1.4 Conditions amenable to continuous and quasi-continuous wave laser treatment.
| Vascular lesions |
|
| Benign pigmented disorders |
|
| Miscellaneous conditions |
|
3.1.2. Visible
light pulsed vascular lasers
3.1.2.1. Flashlamp-pumped
pulsed dye laser
The flashlamp-pumped pulsed dye laser produces short (450-1500 microseconds) pulses of yellow light at a wavelength of 585, 590, 595, or 600 nm. The characteristics of these laser systems induce selective thermal damage spatially confined to cutaneous vessels, making them most effective in the treatment of port wine stains and benign cutaneous ectasias. The shorter pulse duration and the shorter wavelength pulse dye laser may be more effective for smaller, more superficial vessels, while the newer longer pulse duration 0 .5 msec), longer wavelength (595) pulsed dye laser may be more effective for deeper, larger vessels, and for leg veins.
3.1.2.2. Pulsed
KTP laser
A group of pulsed KTP (532 nm) and Nd:YAG (1064 nm) lasers has been
developed with pulse durations in the 1 to 100 msec range, which induce
spatially confined thermal injury to cutaneous vessels. They are effective
in the treatment of benign vascular ectasias and some port wine stains.
3.1.2.3. Visible light, pulsed non-laser sources
By using wavelength filters, a broad band of light from either 515 nm, 550 nm, 570 nm or 590 nm to approximately 1000 nm is produced with a high intensity flashlamp. Depending on the filter chosen, treatment spectra are 515-1000, 550-1000, etc. The pulse width may be adjusted from 1 to 10 msec and the interval between pulses, as well as the fluence, may be selected. Because of the mix of wavelengths used, a more non-specific response may be seen with competing tissue chromophores. However, the longer pulse widths and longer wavelengths may be useful in treating larger vessels.
3.1.2.4. Conditions amenable to pulsed lasers and pulsed light sources
| Vascular lesions |
|
| Miscellaneous conditions |
|
3.1.3. Short-pulsed pigment lasers
A
group of short-pulsed lasers is effective for treatment of a variety
of benign pigmented disorders. All have pulse durations less than
1 p sec, the thermal relaxation time of 1 pm diameter melanosornes.
Their effect is through combined photo-acoustic and photo-thermal
effects.
3.1.3.1. Q-switched
ruby laser
The Q-switched ruby laser produces very short pulses (25 ns) of high-intensity red light at a wavelength of 694 mn. Because red light penetrates through the dermis, the Q- switched ruby laser is effective for the treatment of both epidermal and dermal benign pigmented disorders, as well as blue, black, and green tattoos. b. Q-switched and millisecond pulsed
3.1.3.2. Nd:YAG laser
The Q-switched neodymium yttrium aluminum garnet (Nd:YAG) laser produces 5 -10 nsec high-intensity pulses at 1064 mn in the near infrared spectrum. The laser can be frequency doubled by means of a KTP doubling crystal to produce green light at 532 nm. 1064 nm light penetrates several mm into the depths of the dermis, therefore, even deep dermal pigmented disorders, including black and blue tattoos can be treated. The 532 nm light penetrates only into the upper dermis and is not effective for deep melanocytic processes, but is well suited for treatment of superficial pigmented lesions, such as, lentigines, and red, orange, and purple tattoos.
3.1.3.3. Q-switched
alexandrite laser
The Q-switched alexandrite laser produces either 50 or 100
nsec high- intensity pulses at 755 nm in the red portion of
the spectrum. Like the Q- switched ruby laser, alexandrite laser light
is effective for treatment of epidermal and dermal pigmented processes
and black, blue, and green tattoos.
3.1.3.4. Pulsed
dye laser (510 nm)
This pulsed dye laser produces short pulses (300 nsec) of green (510 nm)
light and is used for the treatment of epidermal pigmented disrders and
red, orange, and purple tattoos. The wavelength is not long enough to
penetrate sufficiently to affect deeper dermally pigmented disorders,
such as nevus of Ota.
3.1.3.5. Conditions amenable to treatment with the short pulsed lasers
| Benign pigmented lesions (epidermal) |
|
| Benign pigmented lesions (dermal) |
|
| Tattoos |
|
| Miscellaneous conditions |
3.1.4. Long
pulsed long wavelength lasers
A group of longer pulsed, non-Q-switched, relatively long wavelength lasers has recently been developed in an effort to damage larger cutaneous targets selectively.
3.1.4.1. Long pulsed ruby laser
Long pulsed ruby lasers produce up to 6 J/cm' in 0.3 to 3.0 msec pulses at 694 nm.
3.1.4.2. Long pulsed alexandrite laser
Long pulsed alexandrite lasers produce over 20 J/cm' and pulse durations of 320 msec 755 nm
3.1.4.3.Flash lamp pumped pulsed light sources
This device emits up to 60 J/cm2 over a broad band in 2 to 20 msec pulsed at wavelength above 590, 615, 645, or 690 nm to an upper limit of approximately 1000 nm.
3.1.4.4. Conditions amenable to treatment with long pulsed long wavelength lasers
| Miscellaneous conditions |
|
3.1.5. Ablative
and cutting lasers
3.1.5.1. Continuous
wave carbon dioxide (CO2) laser
3.1.5.1.1. Characteristics: The CO 2 laser
produces invisible, mid-infrared light at a wavelength of 10600 nm. it can
be used in the continuous mode of operation (focused or incisional) for making
relatively bloodless incisions, or defocused (vaporizational) for ablating
a variety of superficial cutaneous disorders. Incisional surgery with the C02 laser
may be valuable in patients requiring anticoagulation therapy or cardiac
monitoring, and patients with cardiac pacemakers. It may also be valuable
in patients undergoing scalp surgery, and in reducing bruising and post-operative
swelling.
3.1.5.1.2. Conditions amenable to continuous wave CO2 laser treatments in the vaporization or defocused mode
| Miscellaneous conditions |
|
3.1.5.2. Pulsed and scanned CO2 laser
3.1.5.2.1. Characteristics : Most conventional continuous wave CO 2 lasers can be superpulsed, a pulsing technique where the laser produces a train of relatively high power short duration pulses. Although superpulsed CO 2 laser light can theoretically vaporize or cut tissue leaving a smaller residual zone of thermal damage than with continuous wave CO 2 lasers, in practice, this is only achieved using a spot size of 0.8 mm or smaller. Recently developed pulsed CO 2 lasers produce short pulses (< 1 msec) at high power ( > 5 J/cm') that can remove thin layers of skin (30-50 pm) in a single pass with little sub-adjacent thermal damage (50-100 pm). Short-pulsed C0 2 lasers and some scanned CO 2 lasers are effective for resurfacing photoaged and scarred skin. The precision of these laser systems is due to the selective absorption of this wavelength of light by intracellular and extracellular water combined with the appropriate fluence to vaporize tissue and/or the appropriate pulse width to confine residual thermal damage.
3.1.5.2.2. Conditions that may be amenable to treatment with pulsed and some scanned CO 2 lasers
| Miscellaneous conditions |
|
3.1.5.3. Erbium: Yttrium Aluminum Garnet (Er:YAG) lasers
3.1.5.3.1. Characteristics: Er:YAG lasers produce short pulses (< 1 msec), at high powers (> 2.5 J/ cm'), at a wavelength of 2.94 Micron which, like pulsed CO 2 lasers, can remove very thin layers of skin (25 micron) in a single pass with even less thermal damage (5 micron) because of highly selective absorption by intracellular and extracellular water.
3.1.5.3.2. Conditions that may be amenable to treatment with the Er:YAG laser
| Miscellaneous conditions |
|
3.2. Issue
3.2.1. Physician
qualifications
3.2.1.1. General
The physician should have
- Completed residency training in an appropriate specialty such as dermatology, which provides training in cutaneous surgery
- General knowledge of basic laser physics, laser-tissue interaction, and laser safety
- Knowledge of the special safety requirements and elements of the laser, and the prevention and management of potential complications for the specific type of laser to be used
- Knowledge of cutaneous anatomy and basic factors regarding cutaneous wound healing.
3.2.1.2. Specific
- The physician should have laser surgery training in residency, or
- Attendance at an appropriate laser course that includes instruction in basic laser physics, laser safety, didactic lectures on clinical applications of lasers, hands-on experience, or equivalent hands-on experience conducted under the supervision of an appropriately trained and experienced laser surgeon
4. Diagnostic
Criteria
4.1. Clinical
| Medical History |
|
| Physical examination |
|
4.2. Diagnostic tests
- If the clinical appearance of the condition or lesion is insufficient to ensure an accurate diagnosis, then a biopsy should be performed, especially with pigmented lesions.
- In some conditions, the performance of a small representative test area may be necessary in order to accurately determine the proper laser parameters to use and tissue response in the treatment of larger areas.
5. Recommendations
5.1. Treatments
5.1.1. Medical
Not applicable
5.1.2. Surgical
5.1.2.1. Preoperative
- Patient selection is very important and care must be taken to explain the procedure and to ensure that the patient has a complete understanding of the nature of the problem, the treatment options that are available, the risks and benefits of the various forms of treatment, the associated complications, and the potential for scarring and/or pigment changes.
- Pre- and post- treatment photographs may be useful in ensuring reasonable expectations
5.1.2.2.
Anesthesia (See Guidelines of care for local and regional anesthesia
in cutaneous surgery)
The choice of no anesthesia, topical
anesthesia, local anesthesia, local anesthesia in combination with sedation,
cry-anesthesia, regional nerve blocks, intravenous sedation, or general
anesthesia is determined by the physician.
5.1.2.3. Treatment techniques
The treatment techniques may vary depending on the physician's personal experience and judgment. However, the lowest power density or energy fluence that is consistent with a good clinical result is strongly encouraged except when using the CO 2 laser for cutting or ablation. By choosing the most appropriate wavelength and pulse characteristics that limit unwanted thermal damage, therapeutic outcome can be optimized. Achieving optimal results is more difficult and requires a higher level of experience and expertise with continuous and quasi continuous wave lasers than with pulsed lasers.
5.1.2.4. Postoperative findings
The frequency of complications is related to the type of laser that is used and the condition that is treated.
| Occasional |
|
| Rare |
|
5.1.2.5. Other
Follow-up examinations are highly encouraged and are strongly recommended. In many cases, especially tattoos, port wine stains, some pigmented lesions, such as cafe-au-lait macules, several treatments may be required in order to achieve the best results and the greatest degree of improvement. For some pigmented lesions, like cafe-aulait macules and Becker's nevi, repigmentation may occur following treatment and the patient should be given additional information about this situation at a follow-up visit.
5.2.
Surgical setting
Laser surgical treatments may be performed in a physician's office,
an ambulatory surgical center, or in a hospital. The American Academy
of Dermatology has recommended guidelines for office surgical facilities
to help assure the provision of quality office surgical care. (See
Guidelines of carefor office surgical facilities, Parts 1 and 2.) In
addition to the recommendations set forth in those guidelines, the
Academy recommends the following for laser surgery facilities. These
guidelines do not supersede any existing local, state, or federal regulations.
5.2.1. Facility
- The entrance way to the laser facility has a laser device safety sign posted in plain view on the door when the laser is in use.
- Protective measures are taken to prevent stray laser irradiation from leaving the room or from reflecting.
- The room is adequately ventilated with a smoke evacuator.
- Smoking is not allowed in the surgical suite.
5.2.2. Equipment
| Laser | Laser equipment is appropriately signposted. |
| Laser Maintenance |
|
| Eye protection |
|
| Masks |
|
| Vacuum Devices |
|
| Dyes | Dye and
filter changes are performed when the room is empty.
Gloves and an adequate ventilating mask are worn by all person~ nel handling the dyes because of their potential toxicity. Dye spills are reported to the environmental service representative in the building and to the laser company. |
| other | For CO
2 laser surgery, nonreflective or ebonized instruments are used.
Nonflammable surgical drapes are used. Oxygen sources, such as nasal prongs and tubes should be removed from the patient prior to surgery. |
5.2.3. Staff
Appropriate
nursing and technical staff have documentation of laser training and
safety training.
5.2.4. Procedure manuals
A periodic review program is in effect and includes review of
- Adequacy of safety protocols for the laser, vacuum, and power meters
- Procedure manuals for laser use and safety that are available in the facility.
6.
Supporting evidence
See
bibliography (Appendix)
7.
Disclaimer
Adherence to these guidelines will not ensure successful treatment
in every situation. Further, these guidelines should not be deemed
inclusive of all proper methods of care or exclusive of other methods
of care reasonably directed to obtaining the same results. The ultimate
judgment regarding the propriety of any specific procedure must be
made by the physician in light of all the circumstances presented by
the individual patient. For the benefit of members of the American
Academy of Dermatology who practice outside the jurisdiction of the
United States, the listed devices may include indications that are
not currently approved by the U.S. Food and Drug Administration for
the particular type of laser.
APPENDIX
Bibliography
| GENERAL |
|
| HAZARDS ASSOCIATED WITH LASER USE |
|
| TISSUE VAPORIZATION AND RESURFACIN |
|
| VASCULAR LESIONS | |
| Continuous-wave Lasers |
|
| Pulsed Dye Lasers |
|
| Robotized Scanning Devices |
|
| Other Considerations |
|
| PIGMENTED LESIONS | |
| Basics |
|
| Benign Pigmented Lesions |
|
| Tattoos |
|
| Hair
Removal |
|
| SURGICAL SETTING |
|
