Clinical Procedures in Laser Skin Rejuvenation - part 2 pot

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Clinical Procedures in Laser Skin Rejuvenation - part 2 pot

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SKIN Among the absolute hallmarks of an aging face are the changes associated with the skin.The most common changes associated with facial skin aging are those due to photoaging (skin damage related to chronic sun exposure). This results in dyspigmented, wrinkled, inelastic skin, with associated redness and dryness. Furthermore, mild to moderate facial wrinkling and laxity with benign and malignant lesions round out the skin changes that should be addressed through many of the techniques presented in this book. See Tables 2.2 and 2.3, which show the Fitzpatrick and Glogau classi- fications of skin types and wrinkles respectively. VOLUME LOSS It is easy to overlook this particular component of facial aging. Since surgical procedures reposition and lift, it is only natural, but incorrectly, assumed that the cause of that descent is skin laxity and gravity. However, on fur- ther examination, evaluation,and analysis, it is clear that descent and laxity can result from volume loss.As illus- trated in Figure 2.3(a), a fully inflated balloon appears robust and lacks contour abnormalities. However, as seen in Figure 2.3(b), a deflated balloon has the poten- tial to not only descend,but also become deformed.The difference between Figure 2.3(a) and 2.3(b) is nota gen- eral laxity of the balloon’s tarp, but rather the volume inside the balloon. Reinflating the balloon, as opposed to repositioning the tarp, is responsible for eliminating all of those identifiable features. Likewise, many of the features that we will discuss below are in part due to a loss of volume, and one should train one’s eyes to appreciate that volume loss in the following areas: the temporal fossa, the lateral brow, and the malar eminence. Furthermore, volume loss may be seen in the lips and perioral region. Finally, it should be appreciated that overall loss of volume in 14 Clinical procedures in laser skin rejuvenation Table 2.2 Fitzpatrick skin types Type Color Reaction to UVA Reaction to sun I Caucasian; blond or red hair,freckles, Very sensitive Always burns easily,never fair skin, blue eyes tans; very fair skin tone II Caucasian; blond or red hair,freckles, fair Very sensitive Usually burns easily, tans with skin, blue or green eyes difficulty; fair skin tone III Darker Caucasian, light Asian Sensitive Burns moderately, tans gradually; fair to medium skin tone IV Mediterranean,Asian, Hispanic Moderately sensitive Rarely burns, always tans well; medium skin tone V Middle Eastern, Latin, light-skinned Minimally sensitive Very rarely burns, tans very easily; black, Indian olive or dark skin tone VI Dark-skinned black Least sensitive Never burns, deeply pigmented; very dark skin tone Table 2.3 Glogau wrinkle scale Skin type Age (years) Findings 1. no wrinkles Early 20s or 30s Early photoaging: early pigmentary changes, no keratoses, fine wrinkles 2. wrinkles in motion 30s to 40s Early to moderate photoaging: early senile lentigines, no visible keratoses, smile wrinkles 3. wrinkles at rest 50 plus Advanced photoaging: dyschromia and telangiectasia, visible keratoses, wrinkles at rest 4 only wrinkles 60 or 70s Severe photoaging: yellowish skin color,previous skin malignancy, generalized wrinkling 02 Carniol-8028.qxd 8/23/2007 10:24 AM Page 14 the subcutaneous tissue can make certain bony features much more prominent along the infraorbital rim, as well as the submandibular triangle, wherein the submaxillary gland appears quite prominent. CHIN POSITION The next step in the facial analysis process is to assess the location of the chin in relationship to the patient’s lower lip as well as the surrounding tissue. One should look for the appearance of jowling, chin ptosis, chin retrusion, submental fat accumulation and severe neck skin laxity. Following the path of the mandible posteriorly, the next assessment is the general protu- berance and width of the angle of the mandible. Atrophy and medial displacement of the angle of the mandible or atrophy of the masseter muscle can in fact contribute to a narrow and withdrawn facial contour. The nasolabial lines are now assessed for their pres- ence and degree, as well as for the contribution made to these lines by ptotic skin and subcutaneous tissue superior to them. In my experience, the presence of a nasolabial fold is less due to ptosis of the malar fat pad than to atrophy of the malar fat pad with resulting pto- sis (see the balloon concept illustrated in Figure 2.3) of the resulting subcutaneous tissue. Elevation of the malar tissue superiorly and slightly posteriorly assesses Evaluation of the aging face 15 Fig.2.3 Two identical balloons.The one in (a) is inflated and is rigid and wrinkle-free.The one in (b) is partially deflated,its surface contains ripples,like wrinkles,and it is lax and subject to deformation from wind or gravity.Human skin is like the tarp on these balloons.Fully inflated skin appears youthful and robust.Deflated skin sags and reveals wrinkles and furrows. a b 02 Carniol-8028.qxd 8/23/2007 10:24 AM Page 15 the degree of laxity, as well as the overall effect of repositioning this tissue to efface the nasolabial line and to reinflate the malar mound. PERIORAL REGION The lips are now evaluated for the prominence of the white roll, the philtral ridge, and robust red lips.The maxillary teeth should be visible and the mandibular teeth hidden.White lip wrinkles are also assessed. PERIORBITAL REGION Finally, attention is then directed towards the peri- orbital region. Signs of upper lid ptosis are identified and documented. Lower lid laxity and position are identified and documented. Brow position is similarly considered. Unlike the current trend of repositioning the brow cephalically, I find that a lower placed brow in both women and men, in combination with a more robust lateral brow fullness, provides a sophisticated and ageless appearance.An overly elevated brow does not convey youth. It conveys surprise.The absence and presence of forehead, glabellar, and periorbital rhytids are evaluated and documented. Lower lid pseudo- herniation of fat is noted, as is the presence of an infra- orbital hollow.The degree of nasojugal depression is documented, and photographs taken at an earlier age are reviewed to ascertain which of the facial features were present in youth and which were subsequently acquired with aging. SUMMARY Technical expertise, however important to obtaining excellent and consistent results, is only part of the equation.The wrong technique performed flawlessly will typically reveal a result that is below par, while the correctly chosen procedure performed just satis- factorily typically results in acceptable if not extra- ordinary results.We can only recommend the most suitable procedure if we perform a thorough and accu- rate analysis, and that analysis includes not only an assessment of the patient’s facial features, but also their desires, expectations and their notions on which procedures they feel most comfortable with to get there.Therefore, proper and thorough analysis is para- mount for it will lead us to selecting the most appro- priate treatment plan and consequent results for any individual patient and thus predictable and consistent outcomes. Nevertheless, analysis cannot be learned in a vac- uum. Analysis inevitably requires that we compare it with an idealized version, and even then it requires us to understand the pathophysiology by which we got to that point, and then we must correlate those findings with a suitable treatment. PLAN Knowledge in all of these domains and re-exploring all of these disciplines are essential parts of our growth as physicians. 16 Clinical procedures in laser skin rejuvenation 02 Carniol-8028.qxd 8/23/2007 10:24 AM Page 16 INTRODUCTION Although skin resurfacing has been performed for centuries in the forms of chemical peels, sanding, and dermabrasion, it was not until the 1990s that lasers were safely and effectively used as a resurfacing tool. Initially, carbon dioxide (CO 2 ) lasers with a wave- length of 10600 nm (1006 µm) were used as a destructive tool.Technology advanced quickly in the 1990s from continuous-wave CO 2 lasers to pulsed CO 2 lasers to help minimize the thermal damage produced by the older CO 2 lasers. Ultrashort pulse technology emerged, as did computerized pattern generator (CPG) scanning devices that allowed for a more standardized delivery of the laser pulses. Because of the prolonged healing required and the risks associated with CO 2 lasers, the erbium :yttrium aluminum garnet lasers (Er:YAG) lasers with stronger water absorption (2940 nm) and less ther- mal damage were developed. Er:YAG lasers proved to be excellent ablative tools, with shorter healing times, but did not provide the same tightening that was achievable with CO 2 resurfacing. The next advance came in the form of erbium lasers with longer pulse widths that could provide more heating and thermal damage in the skin. The short-pulsed erbium lasers were combined with CO 2 lasers and long-pulsed Er:YAG lasers to try to blend the bene- fits of shorter healing times with more substantial skin tightening. Attempts to improve the laser resurfacing tech- nique continue to be studied, with a concentrated effort now looking at nonablative options to induce dermal remodeling and fractionated skin resurfacing to minimize the risks from skin ablation and to shorten the healing times for patients.This chapter will focus on ablative resurfacing, with an understanding that the principles behind good patient selection and care will remain paramount despite continued changes in the lasers that might be developed. INDICATIONS The most common uses for laser skin resurfacing are to treat wrinkles and acne scars of the face. Any epi- dermal process should improve with laser resurfacing, including lentigines, photoaging, actinic keratosis, and seborrheic keratosis (Box 3.1). Some dermal lesions, such a syringomas, trichoepitheliomas, and angiofibromas, will improve with laser resurfacing, but results will vary with the histologic depth of the process. In our experience, there is a high recurrence rate with dermal lesions. Actinically induced disease, including actinic keratosis (AK) and actinic cheilitis, can respond very well to laser resurfacing. Superficial and nodular basal cell carcinomas have been success- fully treated with the UltraPulse CO 2 laser.The cure rates achieved by Fitzpatrick’s group was 97% in primary lesions (mean follow-up 41.7 months). 1 In addition, the use of laser resurfacing may be used pro- phylactically to reduce the risk for the development of future AK and AK-related squamous cell carcinoma. 2 Prevention of some basal cell carcinomas may be achieved, although this has not been definitively demonstrated. 3 3. Carbon Dioxide Laser Resurfacing, Fractionated Resurfacing and YSGG Resurfacing Dee Anna Glaser, Natalie L Semchyshyn and Paul J Carniol 03 Carniol-8028.qxd 8/23/2007 10:25 AM Page 17 Box 3.1 Indications for laser skin resurfacing • Photodamage • Rhytids • Acne scars • Benign adenexal tumors • Benign epidermal growths • Rhinophyma • Actinic cheilitis • Actinic keratosis • Basal cell carcinoma • Scar revision Despite the multiple uses, by far the prime use in our office is for the improvement of facial photoaging, rhytids, and acne scars.To date, ablative laser resurfac- ing is the most efficacious technique we have to treat perioral rhytids (Fig. 3.1). PATIENT SELECTION The key to successful laser resurfacing is proper patient selection (Table 3.1). Potential candidates need to have a realistic expectation of the outcome, risks, and significant amount of time required to heal, as well as the time to see the final results.The ‘ideal’ patient has fair skin with light eyes, has no history of poor wound healing, and is comfortable with wearing make-up during the postoperative healing period.The history should specifically address issues that relate to wound healing, such as immunodeficiency, collagen vascular diseases, anemia, diet, scarring history, keloid formation, recent isotretinoin usage, and past radiation therapy to the area. The history should include the patient’s general health, current or past medications, and mental health issues. Diseases known to koebnerize are also a relative contraindica- tion – these include psoriasis, vitiligo, and lichen planus. Diseases that reduce the number of adenexal glands or alter their function are relative contraindi- cations and need to be reviewed – these include colla- gen vascular diseases such as systemic lupus erythematosus and scleroderma. A history of herpes, frequent bacterial infections, or frequent vaginal candidiasis is not a contraindication, but should be noted to better plan how to treat the patient during the perioperative period. Equally important is to ascertain the pigment response of the patient (in terms of hyperpigmenta- tion or hypopigmentation) to sun exposure or injuries. In our experience, patients with Fitzpatrick skin type IV are some of the most challenging to treat due to their risks of postoperative dyschromias. Patients will need to avoid sun exposure for several months after the surgery, and the physician needs to document the patient’s ability to do so along with their ability to use broad-spectrum sunscreens daily. In the Midwest of the USA, with four distinct seasons, it is preferable to perform deep resurfacing procedures during the winter months to minimize sun exposure. However, a thorough review of a patient’s travel plans during the 3- to 4-month healing period then becomes impor- tant. Although most patients recognize the risks of a trip to a warm sunny destination, many may under- estimate the risks with higher altitudes such as with snow skiing. 18 Clinical procedures in laser skin rejuvenation Fig.3.1 Significant reduction in perioral rhytids at 4 months. a b 03 Carniol-8028.qxd 8/23/2007 10:25 AM Page 18 PROCEDURE Preoperative care The preoperative care should begin at the time that the patient decides to undergo laser skin resurfacing. Photoprotection and prevention of tanned skin should be maximized before surgery. Melanocyte stimulation before the laser resurfacing may increase the risk of postinflammatory hyperpigmentation after the proce- dure.A sunscreen with a sun protection factor (SPF) of 30 or higher should be used daily, along with an ultra- violet A (UVA) blocker such as zinc oxide, titanium dioxide, or avobenzone.We advise patients to supple- ment sunscreen use with physical measures such as large sunglasses and hats. The use of topical therapy before surgery is com- mon – this might include topical tretinoin, hydro- quinone and antioxidants. It is clear that the use of a topical retinoid is quite valuable before skin resurfac- ing with chemical peels through its action on the stratum corneum and epidermis.The use of topical tretinoin can increase the penetration of the peel, pro- vide a more even peel and enhance healing. 4,5 Due to the high affinity for water with the CO 2 and Er:YAG lasers, these lasers are very capable of evaporating the epidermis without the use of tretinoin.There may be other effects that could theoretically improve the laser resurfacing process and healing. Retinoids regulate gene transcription and affect activities such as cellular differentiation and proliferation. They can induce vascular changes of the skin and a reduction and redistribution of epidermal melanin. 6 Retinoids (at least theoretically) can speed healing and perhaps reduce pigmentary changes.Thus, it is our practice to begin a topical retinoid at least 2 weeks prior to the procedure – even earlier if possible. Because of the relatively common development of postinflammatory hyperpigmentation after laser resur- facing, especially in the darker skin tones, many physi- cians will pretreat with a bleaching agent such as hydroquinone (HQ). HQ works by inhibiting the enzyme tyrosinase, which is necessary for melanin production within the epidermis. It can also inhibit the formation of melanosomes.There is a clear role for HQ products after laser resurfacing to treat hyperpig- mentations; this will be discussed later in the chapter. HQ may not have any clinical effect when used prior to laser surgery, since the melanocytes that it is work- ing on are all removed during the laser procedure. It is certainly not unreasonable to initiate HQ in a 3–5% cream for those patients at high risk for developing hyperpigmentation after their procedure. Like the topical retinoids, it can be irritating and should be dis- continued if it is causing an irritant dermatitis. A rare side-effect of HQ is exogenous ochronosis, but this usually occurs only with prolonged use of higher con- centrations and should not develop even in predis- posed individuals within just a couple of weeks. 7 There is no proven role for the use of topical anti- oxidants, alpha-hydroxy acids, or beta-hydroxy acids, but they are often in the skin care regimen of patients and we do not discontinue their use prior to laser resurfacing. Tobacco smoking can delay wound healing, and patients are strongly encouraged to stop tobacco use.As an alternative, if the patient is unable or unwill- ing to stop smoking at least 2 weeks prior to the Carbon dioxide laser resurfacing,fractionated resurfacing and YSGG resurfacing 19 Table 3.1 Patient selection Absolute contraindications Relative contraindications Unrealistic expectations Tendency to keloid formation Unable/unwilling to perform wound care Tendency to poor wound healing/scar Isotretinoin therapy within prior 6–12 months History of radiation therapy in area History of collagen vascular disease History of vitiligo Diseases that koebnerize (e.g.,psoriasis) Pregnancy/breastfeeding Unable/unwilling to avoid sun exposure postoperatively 03 Carniol-8028.qxd 8/23/2007 10:25 AM Page 19 procedure, he or she is encouraged to switch to a tobaccoless product such as a patch or gum. The use of oral antiviral therapy is standard practice, even if the patient does not have a history of herpes simplex virus (HSV) infections.Typically, famciclovir or valacyclovir is used in prophylactic doses such as famciclovir 250 mg twice daily or valacyclovir 500 mg twice daily. Doses need to be adjusted for renal dys- function.The patient begins therapy the day before the procedure and continues until re-epithelialization is complete. It can be helpful to keep antiviral therapy in the office to administer to the patient if he or she forgot to initiate therapy before the procedure. The use of prophylactic systemic antibiotics is of questionable value prior to surgery and remains con- troversial. 8 A first-generation cephalosporin is typically used by one of us (NLS), while no antibiotics are rou- tinely used by the other (DAG). Interestingly, recent animal studies have shown that CO 2 laser resurfacing reduces microbial counts of most microorganisms on lasered skin compared with skin treated using mechan- ical abrasion. 9 On the other hand, nasal mupricin is routinely prescribed (by DAG) for healthcare workers due to the current high rates of methicillin-resistant Staphylcoccus aureus (MRSA) in hospitals and nursing homes. Unfortunately, the incidence of MRSA in the community is also increasing, and MRSA may be encountered in non-healthcare workers. 10,11 Surgeons should monitor their local communities for recom- mendations regarding community-acquired MRSA. There have been no published studies on the use of antifungal therapy prior to laser resurfacing, although Candida infections can develop during the postopera- tive period, especially when occlusive dressings are used. It has been our practice, and that of others, to treat women with a known history or frequent or recurrent vaginal candidiasis with oral fluconazole after the procedure, even when using open healing techniques. 9 Botulinum toxin is routinely administered to our patients prior to laser resurfacing of the face. Placebo- controlled studies have demonstrated improved results when compared with laser resurfacing alone. 12,13 Pre- operative use of botulinum toxin type A can diminish rhytids as well as textural, pigmentational and other features of skin aging when used in conjunction with laser resurfacing. 13 Our preference is to treat at least 2 weeks prior to laser surgery and repeat at approxi- mately 3 months postoperatively. Patients are given instruction sheets listing skincare items they will need after the procedure along with their prescriptions for postcare medications. These will be discussed later in the chapter. Laser resurfacing Before coming into the office for their procedures, patients are instructed to wash their face well. After drying, they apply a topical anesthetic cream such as EMLA (a eutectic mixture of lidocaine 2.5% and prilocaine 2.5%) under occlusion with a plastic wrap. This is left intact for 2–2.5 hours. One of us (NLS) will reapply the topical anesthetic 45 minutes prior to the procedure.The EMLA not only helps to provide cutaneous anesthesia, but also hydrates the skin, which decreases the procedure’s side-effect profile. 14 Further anesthesia or analgesia can be obtained with nerve blocks, local infiltration of lidocaine, tumescent anes- thesia or diazepam, and, in our office, intramuscular meperidine and midazolam, or ketorolac, is used.The topical agents are removed prior to beginning the laser procedure. When using the UltraPulse CO 2 laser (Lumenis, Santa Clara, CA), the face is treated at 90mJ/45W, and the first pass is usually performed at a density of 7 for central facial areas (periorbital, glabellar, nose, and perioral): the upper and lower eyelids are treated at a density of 6 with the energy setting at 80mJ.The den- sity should be decreased to 6 and then 5 when feather- ing to the hairline and jawline. The first pass is intended to remove the epidermis, which is wiped free with a wet gauze in the central facial areas only, and a second pass is performed to central facial areas at a density of 4–5 (90mJ), depending on the tightening needed. If required, the second pass on the eyelids is performed at a density of 4. Energies are decreased towards the periphery of the face.A third pass may be needed in areas of acne scarring or in the perioral area with deeper wrinkles. As with any laser proce- dure, careful monitoring of tissue response during treatment is performed to determine the necessity of any additional passes and energy level used. 20 Clinical procedures in laser skin rejuvenation 03 Carniol-8028.qxd 8/23/2007 10:25 AM Page 20 A similar approach is taken when using one of the combined Er:YAG lasers such as the Sciton laser (Palo Alto, CA).The first pass is used to remove the epider- mis and frequently 25J/cm 2 (100µm ablation, zero coagulation) with 50% overlap is used. A second or third pass is used to heat and hopefully to induce skin tightening.Ablative and coagulative settings are used with a typical second, pass and a commonly used set- ting would have 50% overlap with 10 µm ablation and 80µm coagulation. Where there are very deep rhytids or scars, the erbium laser in just the ablative setting can be used in a single spot to help sculpt the edges. It is important to remember that when used in the ablative mode, there is very little (if any) hemostasis, and pinpoint bleeding can help identify the depth of resurfacing. Laser resurfacing is best done to the entire face to avoid lines of demarcation between treated and untreated skin.The procedure should be carried into the hairline and at the jaw and chin; a feathering tech- nique should be used. This includes a zone of decreased energy, decreased density, or pulse over- lap.When treating a patient with moderate to severe photodamage, it is important to blend into the neck as much as possible. One approach is to lightly resur- face the neck with a chemical peel; in our office, a Jessners and/or glycolic acid peel is used. Another option is to laser the neck, which will be reviewed later in the chapter. Postoperative care Wound care is critical, and regimens vary among physicians. Occlusive and nonocclusive dressings are available. Occlusive dressings cover the skin and are usually removed in 1–3 days. These can decrease patient discomfort, but may promote infection by har- boring bacteria or yeast.When opaque, the dressings can mask visualization of the wound, thus delaying the detection of an infection. Clear dressings (e.g., Second Skin) allow the patient and medical team to look at the lasered skin.When used in our office, they are most commonly removed on the second day postoperatively and the patient is switched to open healing. Open dressings or nonocclusive dressings are usu- ally petroleum-based ointments. Frequent soaking and cleaning are necessary (at least 4 times daily), followed by frequent application of petroleum jelly, Aquaphor ointment or one of the many wound care ointments that are available. Additives, fragrances, or dyes will increase the chance of contact allergic or irritant der- matitis developing and should be limited as much as possible. In very sensitive individuals, pure vegetable shortening can be used. Dilute vinegar can be used to soak and debride the wound, promote healing, and inhibit bacterial growth. Wound care needs to be performed until re- epithelialization is complete. Depending on the type of laser used and how aggressive the surgeon was with his or her settings, re-epithelialization should be complete within 5–10 days. Prolonged healing times can indicate an infection, contact dermatitis, or other problem, and increases the risks of complications. COMPLICATIONS AND THEIR MANAGEMENT Complications following laser surgery are relatively infrequent, but when they do occur, they need to be treated quickly and efficiently to minimize patient anxiety and long-term morbidity. 15 Obviously, good patient selection, surgical management, and postoper- ative care are necessary to help prevent complications, but, even in the best of cases, complications do occur (Box 3.2). Box 3.2 Complications of ablative laser resurfacing • Activation of herpes simplex virus (HSV) • Bacterial infection • Candidal infection • Delayed healing • Prolonged erythema • Hyperpigmentation • Hypopigmentation • Acne • Milia formation • Contact dermatitis • Scarring • Line of demarcation with untreated skin Carbon dioxide laser resurfacing,fractionated resurfacing and YSGG resurfacing 21 03 Carniol-8028.qxd 8/23/2007 10:25 AM Page 21 The most common complications seen immediately postoperatively are swelling and exudative weeping related to the degree of wounding. If facial swelling is severe, oral or intramuscular steroids, and non steroidal anti-inflammatory agents (NSAIDs) can be administered. Milia formation is common, with the development of small white papules, usually <1mm in size, which need to be distinguished from pustules. Papules are an occlusive phenomenon, and will resolve without treatment. Infections can occur, and may be bacterial, viral, or fungal in nature (Table 3.2). 16 Signs and symptoms include pain, redness, pruritus, drainage (usually not clear), yellow crusting, and sometimes erosions, vesi- cles or pustules may develop (Fig. 3.2). Pruritus, espe- cially, should alert the physician to a possible infection. Appropriate evaluation may include tzanck smear, potassium hydroxide (KOH) prep, gram stain, and cultures to accurately diagnose the causative agent. Treatment should begin early, pending culture results. Fitzpatrick’s group found that half of their patients who developed a post-laser infection had more than one microorganism.Thus, broad coverage should be initiated, and should generally include an agent that will cover Pseudomonas aeruginosa. Acne is another complications that can be seen rela- tively early in the course. Oral antibiotic therapy and discontinuation of petroleum-based ointments usually suffice.Topical acne therapies are not generally well tolerated, due to skin sensitivity, and need to be used judiciously. Contact dermatitis can occur, and may be due to an allergic reaction or an irritant reaction. It may occur within the first few weeks or months after laser resur- facing. Redness, pruritus, and delayed healing may be noted, but vesiculation is rare.Topical antibiotics are a common cause of allergic contact dermatitis, and should be avoided. Patients may be using them without the knowledge of their physician. Topically applied agents should be reviewed and discontinued. Dyes and fragrances that are added to laundry detergents, fabric softeners, and skincare items are also potential causes. Discontinuation of the offending agent(s) and topical corticosteroids should be initiated early. 17 22 Clinical procedures in laser skin rejuvenation Table 3.2 Causative agents encountered in CO 2 laser infections 16 Organism Percent Pseudomonas 41.2 Staphylococcus aureus 35.3 S.epidermidis 35.3 Candida 23.5 Enterobacter 11.8 Escherichia coli 5.9 Proteus 5.9 Corynebacterium 5.9 Serratia 5.9 Herpes simplex virus (HSV) 5.9 Fig.3.2 A postoperative infection at day 3,with redness, edema,yellow drainage and crusting,and pustules.The patient noted increasing discomfort and pruritus. a b 03 Carniol-8028.qxd 8/23/2007 10:25 AM Page 22 PIGMENTARY ABNORMALITIES Hypopigmentation Lightening of the skin is desirable for most patients undergoing facial rejuvenation. Patients who undergo resurfacing of cosmetic units such as the perioral area or periocular area may exhibit a noticeable difference between the ‘new’ treated skin and the untreated skin that exhibits the various dyschromias associated with photoaging.This should be avoided as indicated previ- ously, but when faced with such a patient, treating the remaining skin will lighten the hyperpigmentation and help to blend in the differences.Although topical agents such as retinoids and hydroquinones can be used, visible results take months and are not practical for most patients. Resurfacing is the fastest way to improve patients’ appearance in these cases. Depending on the severity, a chemical peel such as a Jessner’s/35% trichloroacetic acid (TCA) peel may be sufficient, or laser resurfacing can be performed. Superficial resurfac- ing is all that is required for most, and the Er:YAG laser is an excellent device.The goal is to remove the epider- mis, and one or two passes maybe all that is required. This heals rapidly and with minimum risks. In the very sun-damaged patient, it may be difficult to find a good stopping point. In these instances, treat- ing the full face may only accentuate the discoloration of the neck. Light rejuvenation of the neck can be done, but may accentuate the damage to the chest. Light resurfacing can be performed down the neck and chest area, extending onto the breast – but this may then accentuate the damage to the arms and forearms, etc. In these patients, a combination of modalities can be used: topical agents as described above for the entire area; laser resurfacing of the face; lighter resur- facing of the neck and chest (we generally use chemi- cal agents such as 20–30% TCA or 70% glycolic acid, but Er:YAG laser resurfacing is used successfully by many physicians); and chemical resurfacing of the arms, forearms, and hands with 20–30% TCA or 70% glycolic acid. Another option is the use of nonablative laser tech- nology such as the ‘Photofacial’ technique. Several intense pulsed light (IPL) systems are now available, which use a broad-spectrum intense pulsed light source with changeable crystals attached to the hand- piece to filter out undesirable wavelengths. This modality has been applied to the face, neck, chest, and upper extremities. Numerous treatment sessions are required, but are generally well tolerated, with little to no ‘healing-time’ for the patient.The fluence varies with skin type and area, but the neck is generally treated more conservatively and using lower fluences. It is important that the operator carefully place the fil- ters to avoid overlapping and also to prevent skipped areas or ‘footprinting’. Depigmentation True depigmentation of the skin following laser resur- facing is more difficult to treat than the pseudohypo- pigmentation described above. The skin acquires a whitish coloration and does not flush or change color with normal sun exposure (Fig. 3.3).A slight textural change can even be noted at times such that make-up does not ‘stick’ to the skin well or does not last as long as make-up applied to other areas.The latter repre- sents superficial scarring or fibrosis. It can occur after any form of resurfacing, but it is more commonly encountered with CO 2 laser resurfacing and is much less common with Er: YAG resurfacing. Like pseudo- hypopigmentation, depigmentation seems to be more Carbon dioxide laser resurfacing,fractionated resurfacing and YSGG resurfacing 23 Fig.3.3 Persistent depigmentation 2½ years following CO 2 laser resurfacing that was performed in the perioral area only. 03 Carniol-8028.qxd 8/23/2007 10:25 AM Page 23 [...]... results using the pulsed dye laser for scars In a study by Wittenber et al ,23 the flashlamp pulsed dye laser and silicone gel sheeting showed improvement in scar 03 Carniol-8 028 .qxd 26 8 /23 /20 07 10 :25 AM Page 26 Clinical procedures in laser skin rejuvenation blood flow, volume, and pruritus, but the results were no different than the controls Combining modalities will ensure the best results in reduction...03 Carniol-8 028 .qxd 24 8 /23 /20 07 10 :25 AM Page 24 Clinical procedures in laser skin rejuvenation evident when cosmetic units are treated individually or when a cosmetic unit such as the upper lip is treated more aggressively than the surrounding skin Depigmentation has been considered a permanent complication of CO2 laser resurfacing.When evaluated histologically, there is a varying quantity of... Annual meeting, palm Desert, CA, October 20 06) Another alternative to fractional CO2 resurfacing is the 27 90 nm laser (the Pearl, Cutera, Brisbane, California.) This laser is designed to resurface similar to an erbium laser but to provide deeper associated thermal effects to create greater collagen stimulation 03 Carniol-8 028 .qxd 28 8 /23 /20 07 10 :25 AM Page 28 Clinical procedures in laser skin rejuvenation. .. Dermatologic Surgery Annual Meeting, Palor Desert, CA, October 20 06 03 Carniol-8 028 .qxd 8 /23 /20 07 10 :25 AM Page 30 04 Carniol-8 028 .qxd 8 /23 /20 07 3:34 PM Page 31 4 Erbium laser aesthetic skin rejuvenation Richard Gentile MODALITIES OF SKIN REJUVENATION Aesthetic skin rejuvenation (ASR) is certainly not a new process, and historical accounts date back as many as four millennia (20 00 BC) For thousands of years,... scars using intralesional 5-FU Dermatol Surg 1999 ;25 :736–7 22 Alster T Improvement of erythematous and hypertrophic scars by the 585-nm flashlamp-pumped pulsed dye laser Ann Plast Surg 1994; 32: 186–90 23 Wittenberg G, Fabian B, Bogomilsky J, et al Prospective, single-blind, randomized, controlled study to assess the efficacy of the 585-nm flashlamp-pumped pulsed-dye 03 Carniol-8 028 .qxd 8 /23 /20 07 10 :25 AM... carbon dioxide laser Lasers Surg Med 20 01 ;28 :145–9 28 Kilmer SL, Chotzen VA, Silva SK, McClaren ML Safe and effective carbon dioxide laser skin resurfacing of the neck Lasers Surg Med 20 06;38:653–7 29 Manstein D, Herron GS, Sink RK,Tanner H,Anderson R Fractional photothermolysis: a new concept for cutaneous remodeling using microscopic patterns of thermal injury Lasers Surg Med 20 04; 34: 426 –38 30 American... Arch Dermatol 20 01;137:1597–604 7 Penneys NS Ochronosis-like pigmentation from hydroquinone bleaching creams Arch Dermatol 1985; 121 : 123 9–49 8 Nester MS Prophylaxis for and treatment of uncomplicated skin and skin structure infections in laser and cosmetic surgery J Drugs Dermatol 20 05;4 :20 –5 9 Manolis E, Tsakris A, Kaklamanos I, Siomos K In vivo effect of carbon dioxide laser skin resurfacing and mechanical... ablated the epidermis, caused dermal injury, and provided variable thermal effects (dualmode and long- or variable-pulsed Er:YAG lasers) 4 The more recent evolution of devices do not ablate the epidermis, wound the dermis and provide 04 Carniol-8 028 .qxd 32 8 /23 /20 07 3:34 PM Page 32 Clinical procedures in laser skin rejuvenation minimal thermal effects (nonablative lasers and light sources) The fifth... 8 /23 /20 07 10 :25 AM Page 29 Carbon dioxide laser resurfacing, fractionated resurfacing and YSGG resurfacing 24 25 26 27 laser and silicone gel sheeting in hypertrophic scar treatment Arch Dermatol 1999;135:1049–55 Alster T, Lewis AB, Rosenbach A Laser scar revision: comparison of CO2 laser vaporization with and without simultaneous pulsed dye laser treatment Dermatol Surg 1998 ;24 : 129 9–3 02 Bowes LE, Nouri... Dermatol 20 05;4:4–8 12 Zimbler M, Holds J, Kokoska M, et al Effect of botulinum toxin pretreatment on laser resurfacing results: a prospective, randomized, blinded trial Arch Facial Plast Surg 20 01;3:165–9 13 West T, Alster T Effect of botulinum toxin type A on movement-associated rhytides following CO2 laser resurfacing Dermatol Surg 1999 ;25 :25 9–61 14 Kilmer SL, Chotzen VA, Zelickson BD, et al Full-face laser . 585-nm flashlamp-pumped pulsed-dye 28 Clinical procedures in laser skin rejuvenation 03 Carniol-8 028 .qxd 8 /23 /20 07 10 :25 AM Page 28 laser and silicone gel sheeting in hypertrophic scar treat- ment.Arch. used. 20 Clinical procedures in laser skin rejuvenation 03 Carniol-8 028 .qxd 8 /23 /20 07 10 :25 AM Page 20 A similar approach is taken when using one of the combined Er:YAG lasers such as the Sciton laser. resurfacing,fractionated resurfacing and YSGG resurfacing 29 03 Carniol-8 028 .qxd 8 /23 /20 07 10 :25 AM Page 29 03 Carniol-8 028 .qxd 8 /23 /20 07 10 :25 AM Page 30 MODALITIES OF SKIN REJUVENATION Aesthetic skin

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