Keloids are abnormal, raised scars resulting from an overgrowth of tissue following skin injury. This unusual healing response results in a lesion that extends beyond the original wound boundaries. Cryotherapy, which involves the use of extreme cold, is a frequently discussed method for treating these challenging scars. Understanding whether you can effectively “freeze a keloid off” requires examining the underlying biology of the scar and the precise mechanism by which the freezing technique works.
Understanding Keloids
Keloids represent a pathological response to skin trauma, characterized by the excessive production and deposition of collagen during the healing process. They are firm, rubbery, or fibrous nodules that can range in color and often cause symptoms like itching or pain. This excessive scar tissue formation is driven by overactive fibroblast cells that continue to synthesize extracellular matrix components long after the initial wound has closed.
A key feature differentiating keloids from hypertrophic scars is their growth pattern, as keloids spread aggressively beyond the borders of the original injury. Hypertrophic scars, while raised, remain confined to the site of the wound. Keloids rarely regress spontaneously and can continue to expand for months or even years, commonly forming on areas like the earlobes, chest, shoulders, and upper back.
How Cryotherapy Works on Keloids
Cryotherapy, often referred to as cryosurgery, aims to destroy the excessive scar tissue by subjecting it to ultra-low temperatures, typically using liquid nitrogen. The mechanism of action, known as cryonecrosis, involves two main phases of cellular destruction. First, the rapid freezing causes the formation of ice crystals both inside and outside the keloid cells.
Intracellular ice formation physically damages cell membranes and organelles, while the freezing process outside the cells draws water out, leading to cellular dehydration and an irreversible electrolyte imbalance. The second phase involves vascular damage; the extreme cold causes the microcirculation within the keloid to shut down, leading to micro-thrombi formation and vascular stasis. This lack of blood flow results in ischemic necrosis, effectively starving the hyper-proliferative fibroblasts.
The goal of this controlled cell death is to break down the dense, abnormal collagen bundles and ultimately allow the tissue to heal with a flatter, less prominent scar. Specialized techniques, like intralesional cryotherapy, deliver the freezing agent directly into the core of the keloid via a hollow needle. This internal freezing is often more effective for thicker keloids than simply spraying the surface.
Effectiveness and The Treatment Process
Cryotherapy is most effective for smaller, more recent keloids and is typically delivered in multiple sessions. The process involves a freeze-thaw cycle, where the liquid nitrogen is applied for a specific duration, followed by a period where the tissue is allowed to warm up, and then the cycle is repeated. This cyclical freezing maximizes cell death by compounding the initial physical damage with subsequent osmotic stress during thawing.
A single treatment is rarely sufficient, and patients generally require multiple sessions spaced several weeks apart to achieve significant flattening. Surface cryotherapy frequently results in temporary side effects like blistering, pain, and a loss of skin color in the treated area, known as hypopigmentation. Due to the high recurrence rate of keloids, cryotherapy is often utilized as a component of combination therapy.
The most common combined approach involves cryotherapy immediately followed by intralesional corticosteroid injections, such as triamcinolone acetonide. This combination capitalizes on the effect of the freezing to soften the scar tissue, making it more permeable for the corticosteroid. The corticosteroid then works to reduce inflammation and inhibit further collagen synthesis by the fibroblasts, demonstrating a high rate of successful volume reduction.
Other Common Treatment Options
Since keloids are difficult to treat and have a high risk of growing back, a variety of treatment modalities exist beyond cryotherapy. Intralesional corticosteroid injections alone remain a standard first-line treatment, often requiring monthly injections for several months to flatten the scar. Silicone gel sheeting and pressure dressings are non-invasive methods that apply constant pressure and hydration to the scar, which can help reduce its size and prevent recurrence.
Surgical excision is rarely performed alone because it can trigger an even larger keloid to form in the healing area. Therefore, surgery is almost always followed immediately by a preventative therapy like radiation, corticosteroid injections, or cryotherapy to lower the high recurrence risk. Other established options include laser treatments and radiation therapy, often used post-surgery to target the rapidly dividing fibroblasts.