Many modalities can resurface the skin to improve skin quality, reduce age spots, soften fine lines, and treat acne or other scars. Modalities include traditional dermabrasion, chemical peeling, laser resurfacing, and microdermabrasion. The microdermabrasion technique abrades the skin with a high-pressure flow of crystals. All resurfacing procedures exert their effects through different degrees of epidermal and dermal ablation. The results and the indications for each modality depend on the depth of ablation.
History of the Procedure: Facial skin resurfacing can be traced to ancient Egyptian times and the application of abrasive masks of alabaster particles. For millennia, various substances have been used to peel, exfoliate, and rejuvenate the skin. These substances include acids, poultices of minerals and plants, and direct irritants such as fire and sandpaper like materials.
The evolution of chemical peeling and dermabrasion into the procedures in common use today began in the early 20th century. In more recent years, the use of selective photothermolysis in the form of laser resurfacing has become widespread as a skin resurfacing modality.
Microdermabrasion was developed in Italy in 1985; its use was widespread in European countries prior to its introduction and popularity in the United States. This technology offers the advantages of low risk and rapid recovery compared with more traditional resurfacing modalities and can be effective in the appropriate patient population.
Problem: Skin resurfacing techniques, such as dermabrasion, chemical peeling, and the more recent technique of laser resurfacing, have a history of efficacy but also the potential for significant complications.
Monteleone describes the advantages of microdermabrasion, including that it (1) does not require anesthesia, (2) is painless, (3) can be repeated at short intervals, (4) is simple and quick to perform, and (5) does not significantly interrupt the patient’s life.
The need for multiple treatments and their overall effectiveness are limitations of the procedure.
Microdermabrasion produces a superficial ablation, primarily in the epidermis; therefore, this procedure is ineffective for deeper wrinkles or scars. However, for fine lines and more superficial scars, microdermabrasion can be an effective treatment with minimal risk and rapid recovery.
Etiology: Overall skin quality and appearance can be affected by a variety of disorders, including aging, photoaging, acne, enlarged pores, and scarring. A distinction can be made between changes in the skin that occur with chronological aging and changes that occur with photoaging. Intrinsic aging is conceptualized as an irreversible progressive loss of homeostatic capacity and is assumed to be a genetically programmed phenomenon. Photoaging results in changes in gene expression that are distinct from chronological aging. Photoaging results from exposure to ultraviolet radiation.
Ultraviolet radiation consists of both ultraviolet A and ultraviolet B light. Upon contact with the skin, some light is scattered and reflected in the stratum corneum, while other light is absorbed in the epidermis or is transmitted. Ultraviolet B light is shorter in wavelength and more powerful; however, it is absorbed by the epidermis, with only approximately 10% penetrating to deeper layers of the skin. In contrast, approximately 50% of ultraviolet A radiation penetrates the epidermis and reaches the papillary dermis. Therefore, most of the immediate and long-term changes of photodamage occur in the epidermis and upper dermis.
Pathophysiology: The intrinsic process of chronological aging results from thinning of the epidermis and dermis and loss of elasticity. This process affects all layers of the face, including subcutaneous tissue, the musculofascial system, the superficial musculoaponeurotic system, and the facial skeleton. The result is bony resorption, atrophy of subcutaneous fat, attenuation of the musculofibrous system, and alterations of skin surface. The dermal-epidermal junction flattens, which results in loss of rete ridges and a thinner appearance to the epidermis. The dermis also becomes thin, with a decrease in elastic fibers, collagen production, vascularity, and ground substance. The biochemical alterations in collagen and elastin result in a dermis that is more lax yet less elastic and resilient. Collectively, these changes result in fine wrinkling of the skin and sagging of the tissues that overlay the facial skeleton.
Extrinsic photoaging causes degenerative changes in the skin that are superimposed on the normal chronologic aging process. Clinically, this process results in coarse and dry skin, deep wrinkles, sallowness, and dyschromia. Histologically, photoaged skin is characterized by epidermal hyperplasia and dysplasia, a thickened dermis with solar elastosis, actinic vasculopathy, decreased collagen fibers, and increased ground substance.
Heliodermatitis is a term applied to the chronic inflammatory changes and degradation of elastin and collagen observed in photodamaged skin. Photoaging can also damage DNA, which increases the risk of squamous and basal cell carcinoma.
Based on the degree of skin wrinkling, patients can be classified as photoaging types I through IV, as delineated by Glogau. Appropriate resurfacing techniques are chosen to produce superficial, medium, or deep depth of injury according to the severity of photoaging.
The Glogau classification of photoaging groups is as follows:
Mild (typically aged 28-35 y)
- Little wrinkling or scarring
- No keratosis
- Requires little or no makeup
Moderate (aged 35-50 y)
- Early wrinkling, mild scarring
- Sallow color with early actinic keratosis
- Requires little makeup
Advanced (aged 50-65 y)
- Persistent wrinkling
- Discoloration with telangiectasias and actinic keratosis
- Wears makeup always
Severe (aged 60-75 y)
- Wrinkling – Photoaging, gravitational, dynamic
- Actinic keratoses with or without skin cancer
- Wears makeup with poor coverage
Superficial wounding extends to the stratum granulosum or papillary dermis. Medium-depth wounding results from extension into the upper reticular dermis. Finally, deep wounding extends into the midreticular dermis. Care is taken to avoid extending the depth of injury beyond this level because scarring is likely.
In contrast, the Fitzpatrick classification categorizes according to sun-reactive skin type rather than degree of photodamage. This classification helps identify patients who have a propensity for photodamage. For facial resurfacing, this classification can also be used to define the risk of pigmentary changes (eg, dyschromia, postinflammatory hyperpigmentation, permanent hypopigmentation) with resurfacing procedures.
The Fitzpatrick classification of skin types is as follows:
- Skin type I – Very white or freckled, always burns
- Skin type II – White, usually burns
- Skin type III – White to olive, sometimes burns
- Skin type IV – Brown, rarely burns
- Skin type V – Dark brown, very rarely burns
- Skin type VI – Black, never burns
In general, patients with Fitzpatrick skin types I-III tolerate resurfacing procedures with minimal risk of pigmentary complications. While resurfacing may be undertaken in patients with Fitzpatrick skin types IV-VI, the risk of pigmentary change is higher with the deeper wounding that can be achieved with dermabrasion, chemical peeling, and laser resurfacing.
Clinical: Consultation for any resurfacing procedure should address the patient’s concerns and expectations. Distinguishing changes due to photoaging of the skin from changes of chronological aging, which is associated with sagging and loss of skin elasticity, is important. The latter may be best addressed with surgical rejuvenation procedures. If indicated, discuss surgical rejuvenation procedures or a combination of surgery and resurfacing. While some tightening of the skin may occur with resurfacing procedures, facial contour is not significantly affected (ie, jowling, midface ptosis, neck laxity). This is particularly true with superficial resurfacing techniques such as microdermabrasion. The patient must understand and be comfortable with this limitation.
Carefully evaluate the quality of the patient’s skin for changes in texture, acne, or other scarring. Assess the severity of photoaging, and classify it according to the Fitzpatrick skin types. This assessment allows appropriate selection of a resurfacing modality that is both relatively safe and effective for the particular patient. Deep scars and rhytides must be distinguished from those that are superficial because greater depth of injury is required for effective treatment of the deeper lesions. Discuss with the patient the risks and benefits of the different resurfacing modalities.
Address patient lifestyle when gathering the history. The amount of recovery time needed from work or social activities may affect the choice of modality. If the patient has any significant upcoming event, consider this information in order to allow adequate recovery time from any resurfacing treatment.
Address preventative measures if significant photoaging is a concern. Patients who have not been using any sun protection or skin treatment may benefit from these measures as an adjunct to resurfacing treatment.
Gather information concerning past and current use of medications and any medical problems. If the patient is taking isotretinoin (Accutane) or has taken this medication within the last year, resurfacing is contraindicated because of the increased risk of scarring. Importantly, take into consideration any medications or herbal remedies that may produce an anticoagulative effect, particularly when chemical peels, dermabrasion, or laser resurfacing is considered. Similarly, query patients for a history of herpes simplex when chemical peels, dermabrasion, or laser resurfacing is considered because these patients require prophylaxis. When considering phenol peels, elicit information regarding a history of any hepatorenal dysfunction. Also address a history of hypertrophic scarring or keloid formation in the patient and family members. As with all cosmetic procedures, proper patient selection is imperative. Microdermabrasion is most effective with superficial skin conditions because it produces a superficial depth of injury. Superficial skin conditions include early photoaging, fine lines, and superficial scarring. Microdermabrasion does not carry the risks of pigmentary changes or scarring engendered by techniques such as dermabrasion, chemical peels, or laser resurfacing. Therefore, this treatment involves little risk and rapid recovery. Microdermabrasion is well suited for patients with early photodamage and busy lifestyles because the only real downtime is that of the treatment itself.
Even patients with Fitzpatrick skin types IV-VI, who may be at more risk of complications with other resurfacing techniques, may be treated with relative safety. However, care must be taken to not increase the depth of injury by the application of excessive pressure. This recommendation also applies to treatment of the neck. With traditional methods of resurfacing, such as chemical peels, dermabrasion, and laser resurfacing, the neck carries an increased risk of scarring. Because the depth of injury is superficial with microdermabrasion, the neck area may be treated with relative safety as long as proper and careful technique is practiced.
Patient expectations must be realistic. The goal is improvement of the overall skin quality by addressing changes of mild photoaging, age spots, enlarged pores, and acne. Microdermabrasion is also effective for reducing the appearance of fine lines and superficial scars. Results of this technique on brown spots are variable. Patients also must be prepared for the number and frequency of treatments. If patients are unwilling to commit to a series of treatments, then they are unlikely to see significant results and will not be satisfied with the outcome.
Patients must be fully prepared for what microdermabrasion cannot accomplish. Patients with deep rhytides, deep scars, or pigmentary abnormalities are unlikely to achieve significant results. These patients are best treated with other modalities, such as chemical peels, dermabrasion, and laser resurfacing, which result in greater depth of injury. Using these modalities increases effectiveness, but the risk of complications and length of recovery also increase.
ANATOMY:
Epidermis
The epidermis is an integrated epithelial layer composed of 4 distinct zones extending from the dermis to the skin surface. These zones include the basal, spinous, granular, and cornified layers.
The basal layer consists of 1-3 layers of cuboidal or columnar cells. This layer comprises the undersurface of the epidermis and forms projections called the rete ridges, which separate dermal papilla. Melanocytes and Merkel cells can be found in this layer. The basal layer is the main proliferative layer producing cells that replace the terminally differentiated cells lost at the skin surface.
The spinous layer contains polygonal keratinocytes with desmosomal intercellular connections. The keratinocytes become larger, flatter, and contain less water as they approach the skin surface. Langerhans cells, dendritic cells, and other immunomodulating cells are scattered throughout the spinous layer.
The granular layer consists of 2-3 cell layers of keratinocytes with keratohyalin granules. Lamellar bodies, which participate in cornification, are also found in this layer.
The cornified layer, or stratum corneum, is composed of flattened, polyhedral, anucleated cells and varies in thickness. This layer is thinnest over the eyelids and genitalia and is thickest over the soles and palms. The stratum corneum provides a major barrier function for the skin.
Overall, the epidermis replaces itself every 12-14 days.
Skin pigmentation results from the amount and distribution of melanin in the skin. The number of melanocytes actually does not vary between races. Rather, production, distribution, and retention of melanin determine skin color. Melanin is synthesized by melanocytes and is then passed to epidermal cells in the lower epidermal layers. Melanin production increases with exposure to ultraviolet light, which results in tanning.
Dermis
The dermis is composed primarily of connective tissue and is bound tightly to the epidermis by the dermoepidermal junction, which is an extensive interface between the epidermis and papillary dermis. Basal layer keratinocytes and dermal fibroblasts produce dermoepidermal junction components. Anchoring fibrils bridge the basal epidermal layer and papillary dermis.
Collagen is the major structural component of the dermis. Type I collagen constitutes 80% of dermal collagen and imparts tensile strength. Type III collagen comprises 15% of dermal collagen. This type of collagen is found throughout the dermis and serves a primary role in anchoring the epidermis to the dermis. Elastic fibers constitute approximately 3% of the dermis and provide skin elasticity and resilience. Ground substance is an amorphous material between fibrillar and cellular components that imparts turgidity and resilience.
Vasculature, nerves, and sensory receptors are found within the dermis. Hair follicles and sebaceous, apocrine, and eccrine glands are also found within the dermis. The dermal plexus is found in the deep reticular dermis. Other structures include the superficial plexuses of the subpapillary plexus and the plexuses around hair follicles and eccrine glands. The subcutaneous fat derives its blood supply from arteries and veins located in the fibrous septa.
Contraindications: The contraindications for microdermabrasion are similar to those for other resurfacing procedures. These contraindications include the current or recent use (<1 y) of isotretinoin (Accutane), active herpes infection, malignant skin tumors, evolving dermatoses, and certain keratoses.
Because microdermabrasion produces only a superficial depth of injury, scarring and pigmentary changes are almost nonexistent. Scarring and pigmentary changes are significant potential complications for other techniques such as chemical peeling, dermabrasion, and laser resurfacing. All of these techniques must be performed with great caution or avoided altogether in patients at risk for pigmentary changes. Microdermabrasion may be used with relative safety, even in patients with Fitzpatrick skin types IV-VI, who might be at high risk with other treatment modalities. Care must be taken to avoid increasing the depth of injury by improper or overly aggressive technique.
Medical therapy: The results achieved with microdermabrasion can be enhanced with medical therapies in the form of topical skin treatments. Common adjuncts to microdermabrasion include tretinoin, alpha-hydroxy acids, retinoic acid, and topical vitamin C. In patients being treated for hyperpigmentation, the application of hydroquinone between treatments can be useful. Liberal use of sunscreen and moisturizers is also beneficial. Postoperatively, these products serve to address exfoliation and photosensitization. Long-term benefits include reduction of sun damage and photoaging and improved skin moisture.
Surgical therapy: A variety of microdermabraders are available on the market. Several components are common to all systems and include a pump that generates a high-pressure stream of aluminum oxide or salt crystals, a connecting tube that delivers the crystals to the handpiece, a handpiece, and a vacuum to remove the crystals and exfoliated skin. The crystals are then discarded. Handpieces are available in disposable and reusable types. The reusable handpieces must be resterilized after each use. Microdermabrasion can be performed by a physician, nurse, or licensed aesthetician. The most commonly treated area is the face, but microdermabrasion can be used effectively on the neck, hands, and chest. The depth of the treatment depends on the strength of flow of the crystals, the rate of movement of the handpiece against the skin, and the number of passes over the treatment area. Slower movement of the handpiece (allowing longer contact of the abrasive crystals with the skin) and more passes achieves deeper abrasion.
Preoperative details: No premedication is necessary, unless desired. Prior to the procedure, the skin is cleaned of all makeup and oil. No topical or local anesthetic is necessary, although its use is not precluded. Contact lenses are removed, and eye protection is placed to prevent injury from stray particles.
Intraoperative details: The technical key to microdermabrasion is placing the skin under tension so that an effective vacuum is achieved. Typically, stretching the treatment area with the nondominant hand and using the dominant hand to guide the handpiece is the method used to achieve this effect. When treating the neck, the neck is placed in extension to assist in skin tension.
The handpiece is moved over the treatment area in a single, smooth stroke, which can then be repeated. The pressure of the crystal stream is controlled with a foot pedal. Thicker skin, such as that on the forehead, chin, and nose, can be treated more aggressively (ie, adjust the speed of handpiece movement or number of passes). Decrease the pressure when treating the thinner skin of the lower eyelids and upper cheek. Vertically orient all strokes when treating the neck. This approach differs from the approach used in treating the face, upon which a second treatment perpendicular to the first treatment is generally performed.
Between treatments, the face is cleaned of any residual crystals. Usually, 2 treatments per session are sufficient for the face. The desired endpoint of treatment is erythema. Specific areas, such as acne scars or age spots, can be focally treated more aggressively with additional passes. Treatment sessions generally last approximately 30-40 minutes for the face and 20 minutes for the neck.
Postoperative details: The treated area is cleaned with a wet cloth to remove any residual crystals. After drying, a moisturizer or ointment is applied. Continue the application of moisturizer or ointment postoperatively because exfoliation may occur. Erythema generally resolves within hours after treatment, but the patient may experience a mild sunburnlike sensation for a couple of days. Sunscreen should be used liberally because photosensitivity may be increased.
Follow-up care: Effective microdermabrasion usually requires a series of 5-12 treatments. The series can be significantly longer, particularly with acne scarring. Initially, treatments are weekly or biweekly for several treatments, followed by monthly to biannually for maintenance treatments, depending on the patient.
The great advantage of microdermabrasion is its lack of complications. In early years of use, reports cited redness of the eyes, photophobia, and epiphora after examination by an ophthalmologist. The examination revealed conjunctival congestion, crystals adherent to the cornea, and superficial punctate keratopathy. Using eye protection virtually eliminates ocular complications, but corneal abrasion from stray crystals remains a theoretic risk.
The erythema generally resolves within hours after treatment, allowing patients a rapid return to their usual activities. Scarring has not been documented from microdermabrasion, although scarring is theoretically possible when producing any injury to the skin. However, microdermabrasion barely extends through the epidermis, so the depth of injury is very superficial. This fact is both its advantage and its limitation. Superficial injury means rapid healing and recovery with little risk; however, only superficial skin conditions, such as fine lines, quality of the skin, and shallow scars, can be addressed.
In appropriately selected patients, microdermabrasion can be a very effective technique. Patients with photodamage, fine rhytides, age spots, acne, and enlarged pores can experience significant improvement in the quality and uniformity of the appearance of their skin. This improvement is accomplished with little risk and essentially no downtime, excluding the treatments themselves. Therefore, microdermabrasion is well suited to the patient with a busy lifestyle and superficial skin conditions. The number and frequency of treatments can be tailored to the individual patient, depending on the condition and desired result.
Microdermabrasion is not effective for deep wrinkles and scars or ice-pick acne scars because these lesions extend into the deeper layers of the dermis. Similarly, microdermabrasion is not effective for pigmentary problems, such as melasma or postinflammatory hyperpigmentation, because this treatment does not effectively address the dermis where these problems arise. Patients with these problems are best treated with more traditional resurfacing modalities, such as chemical peeling, dermabrasion, and laser resurfacing.
The advantages of rapid recovery and low risk have led to the widespread popularity and use of the microdermabrasion technique. In patients with fine lines and early photoaging, microdermabrasion serves as an effective technique with little or no impact on their lifestyle. The effectiveness of microdermabrasion is limited for deeper skin conditions, such as deep wrinkles and scars, which are currently best treated with other resurfacing modalities. Deeper injury increases complications and recovery time along with effectiveness. Techniques that allow dermal injury and rejuvenation without a degree of epidermal injury currently do not exist, but such techniques may be the future of resurfacing technology.