This review delves into the diverse modalities of laser and energy-based devices used in oculoplastic surgery and cosmetic dermatology for skin rejuvenation, covering ablative (CO 2 , erbium) and nonablative lasers, radiofrequency devices, vascular lasers, light-based lasers, and laser tattoo removal. It emphasizes the importance of preoperative assessment, including skin typing and lesion biopsy, and postoperative care to mitigate complications. With a focus on understanding the different laser compositions and specific indications for various laser types, this study serves as a valuable resource for practitioners navigating the evolving landscape of esthetic medicine.
Key points
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Laser selection depends on the indication and the target tissue and laser absorption curves for the chromophores of water, hemoglobin, and melanin; care must be taken when selecting a laser.
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Ablative lasers (CO 2 , erbium) work by vaporizing tissue and providing photocoagulation, while nonablative lasers and radiofrequency devices induce controlled heating for skin resurfacing and tightening.
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Vascular lasers are absorbed by hemoglobin in blood vessels, while light-based treatments (intense pulsed light and broadband light) can address pigmented lesions with various wavelengths.
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Preoperative considerations include skin typing, lesion biopsy, and prophylactic medications to manage risks.
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Postoperative care involves wound management, sun protection, and skincare to optimize healing and minimize complications.
Introduction
LASER is an acronym coined in 1960 for light amplification by stimulated emission of radiation. A laser releases monochromatic photons of a single wavelength (λ), coherent (same phase), and collimated (unidirectional). These features differentiate a laser from an energy based device. Theoretically, if a laser was shot between the Earth and the moon in a vacuum, the spot would remain the same size because it would not scatter.
Selective photothermolysis refers to the theory of thermal injury induced by the absorption of electromagnetic radiation by a chromophore (target tissue). The laser operator should be familiar with the laser absorption curves for the chromophores of water, hemoglobin, and melanin ( Fig. 1 ). Note that wavelengths in the visible light spectrum are not absorbed by water. This property is what has allowed them either to perform intraocular surgery because they pass through the vitreous or to specifically treat vascular or pigmented lesions of the skin because they do not vaporize water in the dermis. Most lasers that rejuvenate periocular skin are absorbed by water. Laser energy can be reflected, scattered, transmitted, or absorbed in the target tissue.
All other energy-based devices that treat skin, that are not lasers, create heat by other means such as intense pulsed light (IPL), broadband light (BBL), radiofrequency (RF), and microfocused ultrasound.
Currently, a large assortment of lasers and energy-based devices is marketed for cosmetic improvement of aging and sun-damaged skin, and for improvement in naturally and iatrogenically acquired skin lesions and deformities. Specific laser settings are unique to each device. The general variables that can be controlled are wavelength (λ), spot size diameter in microns (μm), pulse width in seconds (s), spot density, energy in joules (J), fluence in joules per centimeter squared (J/cm 2 ), and power in watts (W).
This article reviews the modalities available and is organized into 7 sections:
Section 1—Ablative laser skin resurfacing
Section 2—Nonablative laser skin resurfacing
Section 3—Skin tightening/use of radiofrequency technology
Section 4—Laser treatment of vascular skin lesions
Section 5—Light-based treatment of pigmented skin lesions
Section 6—Tattoo removal
Section 7—Radiofrequency and microfocused ultrasound
Section 1: ablative laser skin resurfacing
Fully ablative lasers include CO 2 and erbium. The CO 2 laser has a wavelength of 10,600 nm (nm) while that of erbium:yttrium aluminum garnet (YAG) is 2940 nm. Because their main chromophore for absorption is water, erbium has nearly 20 times more affinity for absorption by water so may heal with less erythema but not tighten the skin as much as CO 2 allowing for more coagulation and tightening that also is absorbed by other proteins and fat to create additional heat. Fractional lasers remove a portion of the skin as microablative columns (MACs) that are 120 μm wide and thus heal faster than traditional fully ablative lasers that remove 100% of the epidermis with 1000 μm spots that overlap [ ]. The skin is re-epithelialized from cells that are in the skin’s appendages (hair follicles and pores). Re-epithelialization takes about 10 days, and patients are at risk for infection during this time [ ].
Indications for ablative laser resurfacing are facial rhytids, photodamaged skin, and contracted scars. Understanding the appearance of normal healing is critical ( Fig. 2 ). Contraindications include the use of oral isotretinoin, a history of deep dermal peels, collagen vascular diseases, severe lower eyelid laxity, previous lower lid transcutaneous blepharoplasty, and active infections [ ].
Skin should be graded on the Fitzpatrick skin typing scale on types 1 through VI (lightest to darkest, respectively.) Types I to III get the most dramatic results. Types IV through VI are at higher risk for postinflammatory hyperpigmentation (PIH) [ ]. Topical retinoid use may be continued but needs to be withheld after laser for at least 1 month. Skin lesions of concern should be biopsied before the laser. All patients receiving a full-face laser should be placed on prophylactic oral Valtrex 1000 mg/d even if they have never experienced herpes dermatitis [ , , , ].
Treatment may be either a single pass of laser or multiple passes. The areas of the face that heal well from multiple passes are the festoons and perioral area because there are more appendages to promote healing [ ]. The angle of the jaw scars easily because there are few appendages, so this area should never have more than a single pass [ ]. Downtime of 10 days of no makeup should be counseled. Patients also need to understand that ablative laser will treat skin rhytids but not lateral canthal lines formed by muscle insertions from the activity of the orbicularis muscle best treated with botulinum neuromodulators.
Quality standardized photography is important. The procedure is painful, so various forms of preintervention anesthetic are recommended. Anesthesia may be topical (ie, lidocaine cream), but regional injection with lidocaine or general anesthesia may be more comfortable [ ].
Laser safety must include laser-safe eye shields for the patient and protective lenses for the staff. No supplemental oxygen and a sign indicating that a laser is in use should be placed on the door. A smoke evacuator is necessary to remove the laser plume. Sterile skin prep is needed. Laser settings are individual to each machine. One pass may provide some improvement, but multiple passes in a feathered fashion are needed for deeper rhytids and lower eyelid festoons. Protective emollient ointment is placed after the procedure. The area should be cleaned every 2 to 3 hours (often with 1 teaspoon of distilled white vinegar diluted with 1 cup of distilled water) during the healing phase for 7 days. Zinc-based sunblock is required and begins on day 7 when cleanings can be decreased to 4 times per day. Makeup begins at day 10. Daily antioxidants are recommended. Routine skincare with retinol should slowly resume at 1 month when the skin is better healed. Erythema and edema may persist for 4 to 6 months [ ].
Knowledge of complication management is imperative and beyond the scope of this study. Intraoperative complications include bleeding, thermal burns, and eye injury. Postoperative complications include infection, contact dermatitis, prolonged erythema, scar, ectropion, PIH, hypopigmentation, milia, and acne [ , ]. Extensive knowledge of skin care to treat PIH, which occurs in about 8% of patients, is necessary. Over-the-counter and prescription topical cosmeceuticals may be necessary to treat PIH [ , , ].
The CO 2 laser has been used for laser blepharoplasty since 1980 when first pioneered by Sterling Baker, MD [ ]. Incisional continuous wave beams no greater than 200 μm in diameter are needed to coagulate vessels less than 1 mm. This allows for rapid surgery with an excellent view of relevant anatomy with concurrent fat sculpting. The laser serves as an incisor in a focused mode and a coagulator in a slightly defocused mode. The laser finger serves as a dissector, so switching between various instruments is not necessary. The erbium laser cannot be used for blepharoplasty surgery, as it is too specific for water absorption with little absorption of other proteins. Thus, the erbium does not coagulate or help with hemostasis, which is an important aspect of periocular surgery. The CO 2 laser is an excellent device that can be used for upper and lower blepharoplasty with concurrent lower lid laser resurfacing to provide dramatic results without changing the shape of the patient’s eye as can happen with transcutaneous lower lid blepharoplasty [ ].
Section 2: nonablative skin resurfacing
These devices improve skin by creating heat and coagulation without vaporizing the tissue. A wide variety of laser and energy-based devices accomplish this. Indications are to resurface the skin with minimal downtime. These lasers are better for improving dyschromias than tightening rhytids. Disadvantages are that multiple treatments are required and that the results remain less dramatic when compared to ablative lasers. Many brands of nonablative lasers exist, many of which are fractional and thus provide microthermal zones as opposed to the MACs [ , ].
Postoperative recovery may be just 1 to 3 days, but multiple treatments may be recommended. Complications of hyperpigmentation and scarring are less than those of ablative lasers but will need management if they occur [ , ].
IPL and BBL have long been used to give photofacials that even skin tone by being absorbed by hemoglobin and melanin. They can emit wavelengths in the range of 400 to 1200 nm (nm). Filters that allow only certain wavelengths to pass are used to provide optimal treatments for various indications including vascular lesions, pigmented lesions, and hair removal. They do not do much to tighten the skin, since they are not absorbed by water. At least 3 treatments followed by yearly maintenance are generally recommended. More for this indication in the section about dry eye [ , ].
Section 3: skin tightening/lifting with radiofrequency and microfocused ultrasound energy-based devices
RF devices have evolved over 100 years. RF refers to oscillating electromagnetic waves within the range of 3 kHz to 300 GHz. Heating is concentrated on the subdermal tissues. These convert electric energy into kinetic energy. Their Food and Drug Administration (FDA) indication is for skin lifting rather than resurfacing because the target tissue is 34.5 mm beneath the skin. They can be monopolar, which requires a grounding device, or bipolar, which does not. The risk of PIH is less than that of lasers, and thus, darker Fitzpatrick skin types may be good candidates. They create subepidermal wounds at 60° C to tighten the deep layers of the dermis and beneath the dermis by creating heat stimulating new collagen and elastin and thus tissue tightening. Results are subtle, so expectations must be conservative. Some RF devices are combined with microneedling and may take 2 to 3 days to heal [ ].
The ideal patient is aged 35 to 60 years with modest laxity, and moderate nasolabial folds, but with relatively elastic skin with early submental sagging and early jowls [ ]. Multiple treatments are recommended and neocollagenesis can occur over several months [ ].
Indications include brow ptosis, lax jowls, submental ptosis, and lax nonfacial skin and acne scars. These have been used to attempt to tighten festoons, but results are generally equivocal. Because the dermis is minimally disturbed, these devices have the advantage of minimal downtime [ , ].
Relative contraindications include isotretinoin use for less than 6 months, history of herpes simplex virus, history of gold therapy, connective tissue disease with extremely lax platysma, monopolar devices in patients with cardiac arrhythmias or pacemakers, cystic acne, and open wounds [ , ].
Complications include nerve paresis (particularly the marginal mandibular nerve) dysesthesias, depressed scars, undesirable loss of subcutaneous fat, and skin necrosis [ ].
Section 4: laser treatment of vascular skin lesions
Vascular lasers shut down small blood vessels in the skin without disturbing the surrounding skin architecture because the wavelengths are absorbed by hemoglobin and not by water. Lasers, as well as energy-based devices such as IPL and BBL, can be used. The critical issue is that the peak absorption of the chromophore oxyhemoglobin is 577 nm. These are used for telangiectasias, cherry hemangiomas, port-wine stains, rosacea, and dry eye [ ].
Laser and energy based devices wavelengths include the following [ ]:
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Potassium titanyl phosphate (KTP) (532 nm) : red facial telangiectasias, rosacea – does not leave purpura
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Tunable Pulsed Dye (585-595 nm) : port wine stains, rosacea, venous lakes – purpura will last 5-10 days
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Long Pulsed Alexandrite (755nm) : leg telangiectasia venous malformations
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Diode laser (800nm) : blue reticular veins
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Long Pulsed Neodymium Yttrium Aluminum Garnet (Nd:YAG) (1064 nm) : deep reticular veins
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Intense Pulsed or Broad Band Light (IPL or BBL) (400-1200nm) : general matting and dry eye
Indications
Dry eyes are a common indication for ophthalmic professionals. IPL and BBL have been found to decrease problematic dry eyes associated with rosacea, so these are of particular interest to ophthalmologists and optometrists. The benefit may be due to decreasing inflammatory cytokines extruding from dilated facial vessels. Treatment may also target demodex and Propionibacterium acnes . In 2021, the FDA granted De Novo authorization to Lumenis Ltd for its newest IPL device for improving signs of dry eye disease due to meibomian gland dysfunction. BBL by Sciton also is commonly used. Gold eye plated shields are recommended, and the operator must be very conscious of the fact that IPL light is incandescent and not collimated as laser light is, so scatter could reach the eye [ ].
Telangiectasias commonly are associated with rosacea or photodamage and multiple sessions often are required. They are best treated with potassium titanyl phosphate (KTP) laser, IPL, or pulsed dye laser (PDL). Vigorous cooling is needed for surrounding skin structures, especially with the PDL ( Fig. 3 ) [ ].
