Prevention of Hypertrophic Scars or Keloids (RCT)

Keloids and hypertrophic scars are not major illness. However, their effects can be from causing pain and itch which substantially interfere daily activity to as severe as causing deformity and other functional impairment. For standard surgical wounds, taking median sternotomy wounds from open heart surgery and lower abdominal wounds from gynecological wounds for example, the incidence of these problems can be from 10% to 60%. To prevent or treat these problems, physicians have used many modalities. One of the most convenient, most cost-effective and most non-invasive methods for patients is using dressings like silicone sheets, silicone gels or paper tapes, which is on the list of 1st line choices of an international recommendation. According to a literature review, most of the previous studies on similar topics are either of small sample size, on non-standard wounds or comparisons between wounds on different patient groups. The methodologies of previous studies are thus not vigorous enough. To get the highest level of evidence on selecting the best dressings for preventing and treating keloids and hypertrophic scars, we will recruit about 75 patients and apply two selected dressings on each halves of their standard surgical wounds to compare their differences. The investigators hope the result of this study can help us find the best modality to use and can contribute to the welfare of our future patients.

Patients who undergo gynecological surgery with transverse lower abdominal wounds and who undergo cardiovascular surgery with median sternotomy wounds in our hospital will be assessed. Those who have or will have diabetes, chemotherapy, radiotherapy and known history of allergy to silicone will be excluded. Altogether, about 75 patients will be recruited. Each patient's wound will be divided into two halves. One test dressing will be applied to a half, which is determined by random, and a different test dressing to the other half. The total 75 patients will thus be divided into 3 groups of 25 patients. One group will act to compare the effectiveness between silicone gel and silicone sheet, the second group between silicone sheet and paper tape, and the third group between silicone gel and paper tape. The dressings will be applied one week after surgery and at least 12 hours per day until 3 months after surgery. All patients will be followed up at 4 weeks, 8 weeks, 12 weeks, 6 months and 12 months. Three domains of outcomes will be measured. One is the appearance of the scars which will be rated with Vancouver scale, which has been proved to be a reliable scale.34 35 When rating with the Vancouver scale, standardised photographs of the scars will be taken in a standardised photo studio using a single high-resolution digital camera in a standardised light condition and at a fixed distance because any difference in photographic conditions will make difference in the Vancouver scores. The other two domains are pain and itching of the scars, which will be evaluated with Visual Analog Ratings (VAR). Pain and itching are very subjective, so the rating method should be very easy to understand and applicable for our patients and that is why we chose VAR as a tool.

• Other: silicone gel
  silicone gel
• Other: silicone sheet
  silicone sheet
• Other: paper tape
  paper tape

• Active Comparator: Gel vs. Sheet
  One group will act to compare the effectiveness between silicone gel and silicone sheet.
  Interventions:

  • Other: silicone gel
  • Other: silicone sheet
• Active Comparator: sheet vs. paper tape
  The second group between silicone sheet and paper tape.
  Interventions:

  • Other: silicone sheet
  • Other: paper tape
• Active Comparator: gel vs. paper tape
  One group will act to compare the effectiveness between silicone gel and paper tape.
  Interventions:

  • Other: silicone gel
  • Other: paper tape

• Wu WS, Wang FS, Yang KD, Huang CC, Kuo YR. Dexamethasone induction of keloid regression through effective suppression of VEGF expression and keloid fibroblast proliferation. J Invest Dermatol. 2006 Jun;126(6):1264-71.
• Giovannini UM. Treatment of scars by steroid injections. Wound Repair Regen. 2002 Mar-Apr;10(2):116-7. Review. No abstract available.
• Chuangsuwanich A, Osathalert V, Muangsombut S. Self-adhesive silicone gel sheet: a treatment for hypertrophic scars and keloids. J Med Assoc Thai. 2000 Apr;83(4):439-44.
• Suetak T, Sasai S, Zhen YX, Tagami H. Effects of silicone gel sheet on the stratum corneum hydration. Br J Plast Surg. 2000 Sep;53(6):503-7.
• Borgognoni L. Biological effects of silicone gel sheeting. Wound Repair Regen. 2002 Mar-Apr;10(2):118-21. Review. No abstract available.
• Musgrave MA, Umraw N, Fish JS, Gomez M, Cartotto RC. The effect of silicone gel sheets on perfusion of hypertrophic burn scars. J Burn Care Rehabil. 2002 May-Jun;23(3):208-14.
• Quinn KJ. Silicone gel in scar treatment. Burns Incl Therm Inj. 1987 Oct;13 Suppl:S33-40. No abstract available.
• Ahn ST, Monafo WW, Mustoe TA. Topical silicone gel for the prevention and treatment of hypertrophic scar. Arch Surg. 1991 Apr;126(4):499-504.
• Katz BE. Silicone gel sheeting in scar therapy. Cutis. 1995 Jul;56(1):65-7.
• Niessen FB, Spauwen PH, Robinson PH, Fidler V, Kon M. The use of silicone occlusive sheeting (Sil-K) and silicone occlusive gel (Epiderm) in the prevention of hypertrophic scar formation. Plast Reconstr Surg. 1998 Nov;102(6):1962-72.
• Chan KY, Lau CL, Adeeb SM, Somasundaram S, Nasir-Zahari M. A randomized, placebo-controlled, double-blind, prospective clinical trial of silicone gel in prevention of hypertrophic scar development in median sternotomy wound. Plast Reconstr Surg. 2005 Sep 15;116(4):1013-20; discussion 1021-2.
• Atkinson JA, McKenna KT, Barnett AG, McGrath DJ, Rudd M. A randomized, controlled trial to determine the efficacy of paper tape in preventing hypertrophic scar formation in surgical incisions that traverse Langer's skin tension lines. Plast Reconstr Surg. 2005 Nov;116(6):1648-56; discussion 1657-8.
• Abergel RP, Dwyer RM, Meeker CA, Lask G, Kelly AP, Uitto J. Laser treatment of keloids: a clinical trial and an in vitro study with Nd:YAG laser. Lasers Surg Med. 1984;4(3):291-5.
• Bouzari N, Davis SC, Nouri K. Laser treatment of keloids and hypertrophic scars. Int J Dermatol. 2007 Jan;46(1):80-8. Review.
• Chan HH, Wong DS, Ho WS, Lam LK, Wei W. The use of pulsed dye laser for the prevention and treatment of hypertrophic scars in chinese persons. Dermatol Surg. 2004 Jul;30(7):987-94; discussion 994.
• McCraw JB, McCraw JA, McMellin A, Bettencourt N. Prevention of unfavorable scars using early pulse dye laser treatments: a preliminary report. Ann Plast Surg. 1999 Jan;42(1):7-14.
• Kelly AP. Medical and surgical therapies for keloids. Dermatol Ther. 2004;17(2):212-8. Review.
• Staley MJ, Richard RL. Use of pressure to treat hypertrophic burn scars. Adv Wound Care. 1997 May-Jun;10(3):44-6. Review.
• Macintyre L, Baird M. Pressure garments for use in the treatment of hypertrophic scars--a review of the problems associated with their use. Burns. 2006 Feb;32(1):10-5. Review.
• Puzey G. The use of pressure garments on hypertrophic scars. J Tissue Viability. 2002 Jan;12(1):11-5. Review.
• Ng CL, Lee ST, Wong KL. Pressure garments in the prevention and treatment of keloids. Ann Acad Med Singapore. 1983 Apr;12(2 Suppl):430-5.
• Kal HB, Veen RE. Biologically effective doses of postoperative radiotherapy in the prevention of keloids. Dose-effect relationship. Strahlenther Onkol. 2005 Nov;181(11):717-23. Review.
• Narkwong L, Thirakhupt P. Postoperative radiotherapy with high dose rate iridium 192 mould for prevention of earlobe keloids. J Med Assoc Thai. 2006 Apr;89(4):428-33.
• Gusak VK, Fistal' EIa, Speranski? II, Zagoru?ko NN. [Cryotherapy of postburn hypertrophic scars] Klin Khir. 1994;(1-2):15-7. Russian.
• Har-Shai Y, Amar M, Sabo E. Intralesional cryotherapy for enhancing the involution of hypertrophic scars and keloids. Plast Reconstr Surg. 2003 May;111(6):1841-52.
• O'Brien L, Pandit A. Silicon gel sheeting for preventing and treating hypertrophic and keloid scars. Cochrane Database Syst Rev. 2006 Jan 25;(1):CD003826. Review.
• Tredget EE, Nedelec B, Scott PG, Ghahary A. Hypertrophic scars, keloids, and contractures. The cellular and molecular basis for therapy. Surg Clin North Am. 1997 Jun;77(3):701-30. Review.
• Pellard S. Epidemiology, aetiology and management of abnormal scarring: a review of the literature. J Wound Care. 2006 Jan;15(1):44-8. Review.
• Murison M, James W. Preliminary evaluation of the efficacy of dermatix silicone gel in the reduction of scar elevation and pigmentation. J Plast Reconstr Aesthet Surg. 2006;59(4):437-9. No abstract available.
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• Baryza MJ, Baryza GA. The Vancouver Scar Scale: an administration tool and its interrater reliability. J Burn Care Rehabil. 1995 Sep-Oct;16(5):535-8.

Inclusion Criteria:

• Patients who undergo gynecological surgery with transverse lower abdominal wounds.
• Patients who undergo cardiovascular surgery with median sternotomy wounds in our hospital will be assessed.

Exclusion Criteria:

• Those who have or will have:

  • diabetes
  • chemotherapy
  • radiotherapy
• known history of allergy to silicone will be excluded.