Intralesional Cryotherapy With a Argon Gas Based Device for the Treatment of Keloid and Hypertrophic Scars

Intralesional (IL) cryotherapy is a novel treatment for keloids and hypertrophic scars, in which the scar is frozen from inside. Published results are promising, however only Caucasian patient populations have been studied. This prospective evaluation studies the effectiveness of IL cryotherapy in treating keloids and hypertrophic scars in a population consisting of all Fitzpatrick skin type patients.

Multiple devices are available, mostly based on a simple open system. Closed, argon gas based, systems are highly controlled and provide accurate freezing. However, this technique has never been used for IL cryotherapy for the treatment of keloid or hypertrophic scars. All patients with keloid or hypertrophic scars meeting inclusion criteria were treated with a argon based device called Seednet. Scar quality and possible recurrence are assessed pre- and postsurgery (3, 6 and 12 months) with objective devices determine scar color, scar elasticity, scar volume and patient's skin type. In addition, scars are evaluated using the Patient and Observer Scar Assessment Scale.

Inclusion criteria

• Keloids, defined as excessive scar tissue raised above skin level and proliferating beyond the confines of the original lesion
• Hypertrophic scars1 older than 12 months and insensitive to other treatments. Keloids were distinguished from hypertrophic scars based on the clinical judgment of experienced plastic surgeons and on the age of the scar (>1yr)
• A period between previous treatment and IL cryotherapy covered a minimum of 12 weeks
• Patients with all Fitzpatrick17 skin types
• Patients older than 10 years of age

Exclusion criteria

• pregnancy
• diabetes mellitus