Cryotherapy

On this page

Cryotherapy - Chillin' Like a Villain

  • Definition: Controlled tissue destruction by applying extreme cold.
  • Mechanism:
    • Freeze Phase: Rapid cooling → intracellular & extracellular ice crystals, ↑ solute concentration.
    • Thaw Phase: Slow thawing → recrystallization, osmotic shifts, cell membrane rupture.
    • Vascular stasis & inflammatory response → delayed tissue necrosis.
  • Cryogens:
    • Liquid Nitrogen (LN₂): -196°C (most common).
    • Nitrous Oxide (N₂O): -89°C.
  • Technique: "Rapid freeze, slow thaw" principle. Repeat freeze-thaw cycles (typically 2-3) enhance efficacy.

⭐ For benign lesions, target tissue temperature is -20°C to -30°C; for malignant lesions, -40°C to -60°C is required.

Cryogens & Delivery - Ice Ice Arsenal

  • Cryogens (Boiling Point):
    • Liquid Nitrogen (LN2): -196°C (Gold standard, most effective)
    • Nitrous Oxide (N2O): -89°C (Used in cryo-pens)
    • Carbon Dioxide (CO2) Snow: -78.5°C (Older method)
    • Dimethyl Ether/Propane (DMEP): -57°C (OTC wart removers)
  • Delivery Systems:
    • Sprays: Open (direct) or confined (cones); versatile.
    • Contact Probes (Cryoprobes): Metal probes, good for defined areas.
    • Cotton-tipped Applicators: Dipstick method; for small, superficial lesions.

⭐ LN2 is the most common cryogen, achieving the lowest temperature (-196°C) for maximal cell destruction.

Cryotherapy mini cryo gun with spray nozzles and probes

Indications - Freeze These Foes

Error: Failed to generate content for this concept group.

Technique - The Freeze Protocol

  • Preparation: Debulk (e.g., curettage for warts/SKs); cleanse site; LA (optional).
  • Application Methods:
    • Open Spray: LN2 via nozzle (1-2 cm distance from skin).
    • Contact Probe: Cooled metal probe directly on lesion.
  • Freeze-Thaw Cycles (Standard):
    • Freeze Time: Benign lesions (5-30s); Malignant lesions (30-60s+, often longer).
    • Thaw Time: Crucial; allow complete thaw (typically 2-3x freeze time).
    • Cycles: 1-3 cycles common.
  • Endpoint: Achieve adequate frozen tissue halo/margin.
    • Benign: 1-2 mm.
    • Malignant: 3-5 mm.

⭐ Rapid freeze (forms intracellular ice) & slow thaw (allows crystal growth) maximizes cryonecrosis.

Cryotherapy ice ball formation with halo margin

Complications & Aftercare - Post-Chill Fallout

  • Immediate: Pain, edema, bullae (serous/hemorrhagic).
  • Delayed:
    • Pigmentary changes: Hypo- (common) or hyperpigmentation. ⚠️ Higher risk in dark skin.
    • Scarring (rare, hypertrophic/keloid).
    • Nerve damage (transient paresthesia; esp. digits).
    • Alopecia (scalp lesions); Milia.
    • Infection (rare).
  • Aftercare:
    • Gentle cleansing; avoid picking.
    • Blisters: Leave intact; aspirate if large/painful.
    • Analgesia (paracetamol/NSAIDs).
    • Sun protection (SPF >30) crucial.
    • Topical antibiotic if signs of infection.

⭐ Hypopigmentation is the most common long-term complication, especially in darker skin types. oka

High‑Yield Points - ⚡ Biggest Takeaways

  • Liquid nitrogen (-196°C) is the primary cryogen, causing cell death by ice crystal formation.
  • Commonly treats benign lesions like warts, molluscum contagiosum, seborrheic keratosis, and actinic keratosis.
  • Can be used for superficial basal cell carcinoma (BCC).
  • Application methods include spray, contact probe, and cotton-tipped applicator.
  • Two freeze-thaw cycles enhance efficacy, particularly for malignant or resistant lesions.
  • Common side effects: pain, blistering, and hypopigmentation (most persistent).
  • Avoid in melanoma, sclerosing BCC, and cold-sensitive conditions (e.g., cryoglobulinemia).

Practice Questions: Cryotherapy

Test your understanding with these related questions

Incorrect statement regarding the management of frostbite:

1 of 5

Flashcards: Cryotherapy

1/10

Least rate of recurrence following extended currettage is seen with which adjuvant use?_____

TAP TO REVEAL ANSWER

Least rate of recurrence following extended currettage is seen with which adjuvant use?_____

liquid nitrogen

browseSpaceflip

Enjoying this lesson?

Get full access to all lessons, practice questions, and more.

Start Your Free Trial