Keloids form when the skin’s healing process produces an excess of tissue after an injury. This abnormal growth can cause symptoms like itching, burning, and discomfort. Cryotherapy, a method that uses extreme cold to treat the scar tissue, is a common technique used to manage keloids. This approach involves freezing and thawing to target the cells responsible for the excessive scarring.
Understanding Keloids and Cryotherapy
Keloids result from a dysfunction in the body’s natural wound-healing process, where specialized cells called fibroblasts continue to produce collagen long after the injury has closed. The resulting scar extends beyond the original wound boundaries, forming a firm, rubbery nodule characterized by large, abnormal bundles of collagen. This overgrowth distinguishes a keloid from a normal or hypertrophic scar.
Cryotherapy works by applying extremely cold temperatures, typically using liquid nitrogen, to the keloid tissue. The mechanism involves two phases of cellular destruction: a physical phase and a vascular phase. During the physical phase, rapid freezing creates sharp ice crystals within the cells, causing direct damage and irreversible electrolyte imbalances.
The vascular phase involves damage to the microcirculation, leading to blood vessel failure and tissue death through ischemic necrosis. Destroying the overactive fibroblasts and cutting off the blood supply causes the abnormal tissue to break down and shrink, aiming to replace the keloid tissue with a flatter, less prominent scar.
The Sensation During Treatment
The procedure is often described as inherently uncomfortable, particularly for larger or deeper keloids. During the application of liquid nitrogen, patients typically feel an intense, deep cold that quickly transitions into a stinging or burning sensation. This sensation results directly from the extreme temperature causing rapid tissue freezing.
The duration of this acute discomfort is generally short, lasting only as long as the cryogen is actively applied. For patients with smaller lesions, the discomfort can often be managed without intervention, though individual pain tolerance varies.
For larger keloids, medical professionals often use local anesthetic injections prior to the procedure to minimize pain. This numbing ensures that the deep freezing required to destroy the core of the keloid is conducted with minimal sensation. After the anesthetic is administered, the patient may only feel pressure or intense cold, but not the painful stinging.
Immediately after the treatment ends and the tissue begins to thaw, a throbbing or aching pain can start as nerve endings react to the rapid temperature change. This post-application discomfort is usually temporary and signals the start of the recovery process. Planning for proper pain control measures is standard, especially when dealing with lesions larger than half an inch.
Managing Discomfort and Recovery
Following cryotherapy, discomfort transitions from the acute pain experienced during freezing to a more manageable soreness and tenderness. The peak intensity of post-procedure pain typically occurs within one to two hours after treatment, representing a normal inflammatory response as damaged cells break down.
Within 24 to 48 hours, the treated area often develops redness, swelling, and a blister, which can sometimes be larger than the original keloid. Blister formation is an expected outcome of the freezing process and indicates that the treatment successfully damaged the target tissue.
This blister eventually dries out and forms a dark, thick scab that protects the healing tissue underneath. Discomfort during this phase is usually managed with over-the-counter pain relievers, such as acetaminophen or ibuprofen. Proper care of the blister, involving keeping the area clean and protected, is important until the scab naturally separates, which can take several weeks.