Silicone gel in plastic surgery scars: prospective clinical study · prevention of keloid or hypertrophic scars since the 1980s, when scientific articles demonstrated the benefit

Radwanski HN et al.

Silicone gel in plastic surgery scars: prospective clinical study Silicone gel in plastic surgery scars: a prospective study

Associate member, SBCP Resident, Institute Ivo Pitanguy.

1. 2. 3. 4. 5.

HENRIQUE N. RADWANSKI1

WANDA ELIZABETH MASSIERE Y CORREA2

TIAGO JOSÉ REFOSCO

3

4

IVO PITANGUY5

Franco T et al.Vendramin FS et al.ORIGINAL ARTICLE

ADILSON FARRAPEIRA

Assistant Professor and Scientific Advisor, Instituto Ivo Pitanguy. Member, BSPS. Member, ISAPS, ISHRS, ABCRC. Assistant professor, general coordinator of education and research institute Ivo Pitanguy. Member, BSPS.

Professor, Pontifícia Universidade Católica do Rio de Janeiro and the Postgraduate Medical Institute Carlos Chagas. Honorary President, Instituto Ivo Pitanguy. Member and Sponsor, SBCP. Member ANM, CBC, ABL. Visitng professor, ISAPS. FICS, FACS.

Project conducted at the Instituto Ivo Pitanguy, 38th Ward, Santa

Casa da Misericórdia. Rio de Janeiro – RJ.

Corresponding Author: [HNR] Rua Dona Mariana 143, Rio de

Janeiro 22280-020.Tel. 21.2539-0945.

[email protected]

Project accepted for presentation at the 20th Congress of the

ISAPS - International Society of Plastic Surgeons. San Francisco,

CA, USA.

The authors declare having no conflicts of interest.

SUMMARYBackground: The use of silicone gel on surgical wounds began in the 1980’s. Since then, a large number of scientific papers and dozens of different formulas have been published and experimented, attesting the benefits of this product in the prevention of hypertrophic scars and keloids. Although the exact mechanism of action of silicone gel has not yet been elucidated, the most widely accepted theory explains that the occlusive film stimulates the keratinocytes to increase the local secretion of growth factors, subsequently influencing the regulation of fibroblasts. Methods: A prospective study was undertaken at the 38th Ward of the Santa Casa General Hospital, Rio de Janeiro, to evaluate the positive effects of silicone gel on surgical wounds, in a mixed race population. Result: Silicone gel demon-strated a positive effect on surgical wounds following plastic surgery.Conclusion: Silicone gel is useful to enhance the quality of recent scars, in both subjective and objective param-eters, such as erythema, pruritus and firmness.

Keywords: Plastic Surgery, Silicone gel, Wound Healing.

Rev. Bras. Cir. Plást. 2010; 25(3): 428-33428

Rev. Bras. Cir. Plást. 2010; 25(3): 428-33 429

Silicone gel in plastic surgery scars: a prospective study

INTRODUCTION

METHOD

Case Selection

Improving the final appearance of a scar is a challenge that involves various medical specialties, particularly plastic/cosmetic surgery. The natural development of a cutaneous incision results, in most cases, in a fine, linear scar, but there is always the risk of a hypertrophic scar or keloid formation1,2. Despite the development of knowledge of the healing process, it has still not been possible to execute a cutaneous incision without leaving a scar, thus, it represents the consequence of any surgical intervention. A cosmetic surgeon must, as such, plan the extent and location of their incision, keeping in mind the possibility of leaving a bad quality scar. Silicon, in various formulations, has been used in the prevention of keloid or hypertrophic scars since the 1980s, when scientific articles demonstrated the benefit of these products on scars resulting from surgical incisions, burns and trauma, and other causes. The results from most studies indicate a significant improvement in the final quality of scars, from various etiologies, after the use of silicon gel3-8 based products. Oddly, however, all such studies were conducted with light skinned patients. It is known that there is a greater tendency for keloid or hypertrophic scarring in persons with darker skin. This study was interested in evaluating the development of scars in a mixed-race population, using a product containing fast-drying silicon gel in scars exclusively result-ing from cosmetic surgery. Thus, a prospective study was planned in the Plastic Surgery Department of the Prof. Ivo Pitanguy, in the 38th Ward of the Santa Casa da Misericór-dia in Rio de Janeiro.

The patients were registered at the 38th Ward of the Santa Casa da Misericórdia in Rio de Janeiro, at the Instituto Ivo Pitanguy, and were selected according to the study inclusion and exclusion criteria. The inclusion criteria were: individu-als between 15 and 65 years of age, a recent surgical scar, and signing of an informed consent form. The exclusion criteria were: presence of a systemic or metabolic illness or open surgical wound, pregnancy or childbearing potential, use of other concomitant medication on the scar, participa-tion in another clinical study in progress or in the previous 60 days, history of allergy to silicon, and inability to apply the gel. The study was conducted between November, 2007, and April, 2009, with a total of 128 consecutive patients. Only patients who were in post-operative plastic surgery, and who had referrals for scar treatment in an attempt to

obtain a better cosmetic result were evaluated. Of the patients who completed the study, 96% had scars originat-ing from surgical procedures in the department itself, and 4% originating from other departments. The study was approved by the Ethics in Research Committee of the Santa Casa de Misericórida of Rio de Janeiro, and was conducted in compliance with the Helsinki Declaration, revised in 2000, and Resolution 196/96 of the National Health Council.

Evaluation parameters All selected patients were submitted to surgical scar treatment in the remodeling phases (i.e. between removal of the last sutures and the 3rd month post-operation), exclu-sively with silicon gel (Polysiloxanes, Silicon Dioxide, Kelo-cote®, Advanced Bio-Technologies, Inc) over the entire surface of the scar, twice daily, over a period of 3 to 6 months. The patients were evaluated during three distinct periods of development. The first assessment occurred one month after beginning treatment, the second during the second to fifth month of product use, and the final assessment between the third and sixth month of product use. The initial evaluation included anamnesis, collection of demographic data, and verification of inclusion and exclusion criteria for the study. For all assessments, the patients completed a quality of life questionnaire, and their scars were examined by one of the medical investigators. Evaluation of the treatment’s efficacy was performed using the Vancouver Scale (Appendix 1). It should also be noted that photographic documentation was conducted from the initial assessment until clinical discharge for all patients who completed the study.

Statistical analysis Statistical analysis consisted of the following parameters: • Variation in the Vancouver Scale over three points in time (initial, intermediate and final), analyzed by ANOVA and the Friedman test of the respective multiple comparisons; • Variation in categorical data (erythema, relief, and flexibility) across the evaluation instances was analyzed using the McNemar Test, corrected.Parametric data will be presented as the mean ± the standard deviation, and the non-parametric data will be presented as the median. (Non-parametrical methods were used, since the variables did not present a normal distribution, due to the dispersion of the data and the lack of symmetry in the distri-bution). The criteria adopted for determination of signifi-cance was a level of 5%. The statistical analysis was processed by the SAS System® statistical software.


Radwanski HN et al.

RESULTS

Appendix 1: Evolution - The Vancouver Scale

ErythemaPurpleRedPink (with some reddish components)Normal skin color (with some pink components)Normal skin color

Relief (height)6.0 mm 6.0 mm4.0-6.0 mm 3.0-6.0 mm2.0-4.0 mm 1.0-3.0 mm0.2-2.0 mm 0.1-1.0 mmNormal/Flat Normal/Flat

Flexibility (hardness)

the scar

Flexible - having moderate resistanceFlexible - having minimal resistanceNormal

Itchiness 0____5____10Score 0 (no itchiness) up to 10 (worst itchiness ever experienced)

Sensitivity (pain) 0____5____10Score 0 (no pain) up to 10 (worst pain ever experienced)

Table 1. Characteristics of the study population.

n %

Gender Female 67 97

Tobacco use Yesa 11 15.9

Important Comorbidities

absent 55 79.7

High Blood Pressure 9 13

other b 5 7

History of abnormal healing

absent 64 92.8

personal history 4 5.8

family history 1 1.4

Skin type always burns 3 4.4

usually burns

14 20.6

sometimesburns

26 38.2

never burns 25 36.8

Treatment duration (months, average)

69 6

a a current + ex-smoker b asthma, allergic rhinitis, hypercholesterolemia, nephrolithiasis, labyrinthitis.

Table 2. End of treatment.

Variable Category n %

Reason for ending treatment

Accordingto plan 69 53.9

Patient interruption 40 31.3

Patientunavailable 1 0.8

Allergy / Side effects 5 3.9

Other 13 10.2

Adherent - firm and adherent to the local structures that surround

Firm - inflexible, difficult to move, resistant to manual pressure

The demographic characteristics of the study population are presented in Table 1. Women accounted for 98% (125 of 128 subjects); 80% of subjects presented no comorbidity whatsoever. In total, 128 patients were included in the study, but the longitudinal analysis of the data conducted in all three instances was from 69 patients. Table 2 outlines the reasons for termination of treatment. It should be noted that 69 completed the study as planned, so these are the patients included in the analyses for this study. Although part of the loss is attributed to adverse side effects, most of the loss is due to patients voluntary discontinuation from the study, largely because of the good results obtained principally at the beginning of treatment, thus favoring discontinuation of



Table 3. Characteristics of the scar.

n %

Scar Classification normal 86 67.2

20 15.6

red8 6.2

lower keloid 1 0.8

recent 13 10.2

Depth of tissue injury

tendon/muscle 100 78.1

hypodermis 16 12.5

deep dermis 2 1.6

data not available

10 7.8

Location of the scar

thorax 75 58.6

abdomen 40 31.3

face 4 3.1

upper limb 5 3.9

other 4 3.1

Healing processa primary 122 95.3

Length mm (median) 128 475

Width mm (median) 128 2.5a primary or secondary

Pretreatment symptoms and indications n %

Symptom

itching 46 66.726 37.7

pain 22 31.9sensitivity/touch 9 13sharp 9 13tightening 19 27.5at least one present 13 18.8

Indication

erythema 60 87relief 33 47.8hardening 28 40.6enlargement 25 36.2at least one present 5 7.2

the use of the product. There was an incidence of 6.25% (n=8) of adverse effects in all of the patients (i.e. 128), mainly erythema and itchy skin, which improved upon discontinuation or a pause in treatment, with no need for any specific treatment. Table 3 presents the data related to the type of scar treated in the study. Most of the patients had been subject to body contouring procedures, thus the majority of the scars were in the chest and abdomen. A total of 86 patients (67.2%) had their scars initially classified as normal, and 28 patients (21.8%) had their scars classified as hypertrophic. The average length and width of the scars were 475 mm and 2.5 mm, respectively. Table 4 shows the frequency (n) and percentage (%) of initial symptoms/signs of scarring in the sample of 69 patients. The most frequent symptom observed was itchiness (58.6%), followed by twinge (26.6%) and pain (32%); for signs, there was erythema (64.8%), followed by relief (28.9%).

Assessment of efficacy Figure 1 displays a graph with the sum or scores on the Vancouver Scale at the initial, intermediary, and final assessments. According to the tests applied, there was a significant improvement in scars treated with the product, using the Vancouver Scale (p<0.0001) as a parameter throughout treatment, especially between the initial and intermediate assessment (i.e. in the first three months), observed by a decrease in the overall score. Regarding the analysis of symptoms in particular, there was significant improvement for itching and sensitivity (p<0.0001) during treatment, especially among the early and intermediate assessments, as seen in Figure 1. A qualitative analysis of the scars was conducted in relation to erythema, relief, and flexibility of the scars in treatment, including only patients who completed all three reviews (n=69). For the three characteristics analyzed, there was a statistically significant improvement, however, in relation to relief, the significant improvement occurred between the initial and final assessment (p<0.0001), while erythema and flexibility showed a more rapid response, as observed in greater detail in Figures 2A and 2B. Treatment efficacy was considered excellent in 62% (n=42), good in 28% (n=19), moderate in 7% (n=6) and unsatisfactory in 3% (n=2).

Discussion The healing process is dynamic, classically divided into three overlapping phases: inflammation, proliferation and remodeling. It is after the second week of the injury that remod-eling of collagen, with constant synthesis and degradation.

linear hypertrophic

hypertrophic large/

Table 4. Initial classification of the scar.

sharp pain


Radwanski HN et al.

DISCUSSION (CONTINUED)p < 0,0001 (Friedman ANOVA Test)

Initial Intermediary Final

Vanc

ouve

r Sca

le

2422201816141210

86420

Initial IntermediaryEvaluation

Final

Ery

them

a (%

)

A 100

50

0

normalpinkred spotsred/purple

Initial Final

Rel

ief (

%)

B 100

50

0

normal1-2 mm2-4 mm

Figure 1 - Vancouver Evaluation Sum of scores obtained with the Vancouver scale in initial, intermediate, and final examinations. The results are represented by the median, interquartile value, minimum and maximum values for each variable. Friedman ANOVA Test, p<0.0001.

Figure 2 - Development of percentage or indications and symptoms. A. Percentage of erythema, classified according to the Vancouver scale, in initial, intermediate, and final examinations. B. Percent of relief, classified according to the Vancouver scale, in initial, intermediate, and final examinations.

IntermediaryEvaluation

The increase in cross-linking determines the progressive strengthening of the scar, which continues to remodel over a long time, but without ever attaining the normal strength of unaffected skin. The basic alteration which occurs, both in keloid and hypertrophic scarring, is continuous fibrous tissue proliferation. The distinction between the two entities is the tendency for the keloid to project beyond the original borders of the injury. Surgical incisions are generally clean wounds, having the best conditions for favorable development. Every surgeon, in any specialty, must guide their patient regarding preven-tive care to ensure the best quality for the final scar. After removal of the last sutures (normally up to the end of the second week after surgery), normal measures should be adopted to accelerate scar development. In addition to directly treating it, it is important to involve the patient, informing them of their role in caring for the scar, including: daily massage with mineral oil (to hydrate the scar and manipulate the forming collagen network); protection against solar radiation; constant application of silicon gel for at least three months. The use of silicon gel in scars dates from the early 1980s, initially indicated for treatment of extensive scarring from burns. Since then, a large number of studies, and dozens of different silicon gel formulas have been released, attesting to the benefits of this product in the prevention of keloid and hypertrophic scars. All the same, the precise mechanism of action is still a matter of debate. The most widely accepted hypothesis is that occlusive dressing, achieved with the various applications of silicon gel, stimulates keratinocytes to increase secretion of growth factors locally, and, conse-quently, influences the regulation of fibroblasts. It is also believed that greater hydration, by occlusion, decreases capillary permeability, inflammatory and mitogenic media-tors, and collagen synthesis. Different silicon gel-based products are available on the market, and the literature reveals that there is no difference between them in terms of improvement in the healing quality. They are all biocompatible, transparent and odorless and may be used with pediatric patients. The gel forms a layer that is semi-occlusive to water and permeable to gas exchange. Presentation thereof varies, ranging from tape, cohesive gel, spray, and fast-drying liquid gel forms.. Despite the similarities, comparison of these products indicates that there are advantages in applicability. Being a fast-drying gel (i.e. less than 1 minute), the product used in this study is not sticky, allowing the subject to wear clothes directly in contact with the scar. It is also possible to place other substances over the silicon gel film, such as sunscreen or makeup. Finally, unlike silicon gel tape, it is possible to



Acknowledgements

CONCLUSION

REFERENCES

1.

2.

3.

4.

5.

6.

7.

8.

use the fast-drying liquid gel in exposed areas, such as the face, without needing adhesive tape to keep the product in contact with the skin. In this study, after following 69 patients for six months, we observed a progressive improvement in the appearance of the scar, rated with the Vancouver scale. In general, an improvement in symptoms was observed, without any other differences, between the initial and intermediate period, like itching and sensitivity (i.e. all improvement observed was restricted to the first period, of three months). But in the signs assessed, such as erythema, relief and flexibility, additional improvement was detected between the interme-diate and final visit. The group studied was representative of a typical mixed-race population (and therefore more subject to less favorable scar healing), giving greater significance to the study, since the literature only reports studies conducted in patients with light skin color. However, in this study, it was decided not to treat just a portion of the scar (keeping the remainder untreated portion as a control), and there was no untreated group (i.e. a control group), which would allow comparative analysis between the benefit of the product on treated subjects, and patients with no treatment. Such a comparison was conducted empirically, drawing on the researchers' clinical experience. It is recommended to begin the use of the silicon gel as soon as the last sutures have been removed. The product should not be applied to open wounds, or on patients with a history of allergy to silicon. Ideally, the product should be left in contact with the scar 24 hours/day, which requires application thereof once or twice per day, depending on the patient's bathing habits. The consensus in the literature is for the continuous use of the gel for three months; If no improvement is seen, the use of the product should be extended for an additional three months.

In cutaneous scars from cosmetic surgery, treated with fast-drying silicon gel, clinical monitoring for 3 to 6 months revealed a significant improvement in the following param-eters: itching and "tightening"; hardening; elevation; redness. Empirical comparison with patients who did not use the silicon gel revealed that these benefits are perceived in the first weeks of use. Tolerability of the product has been excellent, with rare cases of skin irritation. The fast-drying silicon gel proved to have the same benefits as other silicon based products, but with the advantage of easier application. The study concluded that the use of the silicon gel on post-cosmetic surgery is safe and effective in the prevention of poor quality scars.

Pitanguy I, Brentano JM, Bos H, Salgado FS, Mazzarone F. System-atization of dressings and postoperative follow-up in cosmetic surgery. Rev Bras Cir. 1988;78(1): 67-78. Fagundes FP, Lago EHJ, Lima BB, Carneiro SC. Healing, scars and bandages. In: M. Ramos-E-Silva, M. C. Ribeiro de Castro, editors. Fundamentals of Dermatology. Rio de Janeiro: Editora Atheneu; 2009. p. 2077-2100. Perkins K, Davey RB, Wallis KA. Silicon gel: A new treatment for burn scars and contractures. Burns. 1982;9:406-410. Mustoe TA, Cooter RD, Gold MH, Hobbs R, Ramelet AA, Shake-speare P et al. International clinical recommendations on scar management. Plast Reconstr Surg. 2002;110:560-571. Berman B, Perez OA, Konda S, Kohut BE, Viera MH, Delgado S, et al. A review of the biologic effects, clinical efficacy, and safety of silicone elastomer sheeting for hypertrophic and keloid scar treatment and management. Dermatol Surg.2007;33(11):1291-1303. Reish R, Eriksson E. Scars: A review of emerging and currently available therapies. Plast Reconstr Surg. 2008;122:1068-1078. Mustoe TA. Evolution of silicone therapy and mechanism of action in scar management. Aesthetic Plast Surg. 2008;32(1):82-92. Wolfram D, Tzankov A, Pülzl P, Piza-Katzer H. Hypertrophic scars and keloids: A review of their pathophysiology, risk factors and therapeutic management. Dermatol Surg. 2009;35(2):171-181.

To Patricia Cristina dos Santos Costa, Doctor of Physiology, Instituto de Biofisica Carlos Chagas Filho – UFRJ, for guiding the study, and to Rosangela Aparecida Martins, MSc in Statistics from UFRJ. The study was financed by the Instituto Ivo Pitanguy and Farmoquímica.

Silicone gel in plastic surgery scars: prospective clinical study · prevention of keloid or hypertrophic scars since the 1980s, when scientific articles demonstrated the benefit

Documents