Prevention of Hypertrophic Scars or Keloids

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.

Eligibility Criteria:
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.