Acute complications include headache, pain, and blister formation. Delayed complications include hemorrhage, infection, and excessive granulation tissue formation. Prolonged-temporary complications include milia, hyperpigmentation, and change in sensation. Permanent complications include alopecia, atrophy, keloids, scarring, hypopigmentation, and ectropion formation. Relative contraindications include cold intolerance, cold urticaria, cryoglobulinemia, history of pyoderma gangrenosum, and Raynaud disease.
Absolute contraindication includes the use of cryotherapy near the eye margins.
The cryotherapy operator must be aware of the complications associated with this modality, such as dark-skinned individuals being prone to hypopigmentation. One needs to be aware of the fact that lesions may need to be treated multiple times before resolution. The most common applicator device is the spray gun. This vacuum bottle holds liquid nitrogen and releases the liquid with reasonable accuracy. Q-tips or an applicator stick with cotton at the tip is another method to treat benign lesions.