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Cryosurgery and Electrosurgery. Adam O. Goldstein, MD Associate Professor UNC Dept Family Medicine Chapel Hill, NC aog@med.unc.edu. Objectives. Know indications and techniques for using cryotherapy to treat common dermatologic conditions
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Cryosurgery and Electrosurgery Adam O. Goldstein, MD Associate Professor UNC Dept Family Medicine Chapel Hill, NC aog@med.unc.edu
Objectives • Know indications and techniques for using cryotherapy to treat common dermatologic conditions • Know indications and techniques for using electrocautery to treat common dermatologic conditions • Know side effects of cryotherapy and electrosurgery
Cryosurgery • Purpose: For rapid treatment of common skin conditions • Benign lesions: warts, seborrheic keratoses • Premalignant lesions: actinic keratoses • Malignant tumors: Basal cell/squamous cell carcinomas • MUST KNOW THE DIAGNOSIS
Cryosurgery • Tissue destruction: -10 to -20 C. • Malignant cell kill: -40 to -50 C. • Chemical refrigerants -70 to -94 C. • Cold cryoprobes -90 C. • Liquid Nitrogen -196 C.
Chemical Refrigerants • Verruca-Freeze • Low start-up costs • Useful for satellite offices • Not approved treatment for malignant lesions
Verruca Freeze • Speculum size (2-12 mm) that encompasses lesion • 1 “freeze” cycle = • Fill speculum with spray 1/8- 1/4 inch (3-6 seconds) • Allow fluid to evaporate (20-25 sec.) • 130 “freezes” per cannister • $200 start-up costs • Long shelf life- 4-5 years
Cryoprobes • Nitrous oxide cryoguns • Tanks with cart, hand gun, pressure gauge and regulator • Useful if liquid nitrogen not available
Nitrous Oxide • Put water soluble gel to lesion • Select probe size • Apply activated cryogun probe tip to skin
Liquid Nitrogen Advantages for clinician • Cheap after set-up costs • Easy to learn • Multiple lesions at one time • Do not need assistant to perform
Liquid Nitrogen Advantages for patient • No local anesthetic needed • Pain tolerable • No sutures • Wound care relatively easy
Liquid Nitrogen Disadvantages for clinician • Start-up costs $1000 • Storage facilities • Filling canisters
Liquid Nitrogen • Boiling point -196 C. • Cellular destruction d/t: • ice crystal formation • cellular dehydration • protein and enzymatic denaturization • Destruction more pronounced with: • rapid freeze • slow thaw cycle
Liquid Nitrogen: Equipment • Liquid nitrogen • Storage tank= Dewars • 2-30 L, filled q 3-4 weeks • Costs: Tanks: Holding timeCosts • 2 L 48 hrs $200 • 10 L 6-8 weeks $475 • 20 L 8-12 weeks $535 • 30 L 14-16 weeks $620
Liquid Nitrogen: Equipment • Filling Dewars; pouring, ladles or devices • Devices affixed to dewar: Ladels Valve: $310 Tube: $150
Liquid Nitrogen: Equipment • Thermos bottle with hole and cotton tipped swab or • Cry-AC Spray/cryogun (C-tip, mini-gun) 10 oz 16 oz 12 oz $670 $670 $650 12 hr 24 hr 24 hr
Cryosurgery • Frozen areas turn white = “freezeball” or “iceball” • Depth of freeze should be 1 X radius of freeze • Lethal Zone • Tissue temp < -20 C. • 2-3.5 mm inward from outer margin iceball • Freeze 2-3 mm beyond lesion edge
Cryosurgery Remember ….. • Always best to underfreeze rather than overfreeze • Hold canister perpendicular to skin • Usually 2-3 freeze/thaw cycles
Cryosurgery • Cotton tipped swabs • Informed consent-oral vs written
Cryosurgery: Freezeball Time • Freckles/lentigos: 3-5 seconds • Small papules: 5-10 seconds • Seborrheic Keratoses: 30-40 seconds • Actinic keratoses: 40-60 seconds • SCCa/BCCa: 80-90 seconds
Cryosurgery: Freezeball Size • 1mm- freckles/lentigos • 1-2 mm- most benign skin lesions • 2-3 mm- most warts • 3-4 mm- most actinic keratoses • 4-6 mm- superficial SCCa, BCCa
Cryosurgery • Thermocouple • $500 for temperature monitor and thermocouple needle
Cryosurgery: Effectiveness Low • Vascular lesions: e.g. angiomas • Achrochordans
Cryosurgery: Effectiveness Medium • Xanthelasma • Dermatofibroma • Keloid • Molluscum • Prurigo nodularis • Sebaceous hyperplasia
Cryosurgery: Effectiveness Medium-High • Seborrheic keratosis • Verruca * • Condyloma acuminata • Lentigo • Freckles
Cryosurgery • Verruca: • Often resistant • Warts on hands • Plantar warts • Flat warts
Cryosurgery: Effectiveness High • Actinic keratosis • Superficial Basal Cell Carcinoma • Superficial Squamous Cell Carcinoma
Cryosurgery: Superficial BCCa/SCCa • Establish pathological diagnosis first • Success rates > 95%
Cryosurgery: Special Populations • Children • In general avoid b/c pain • Use EMLA cream if needed • Useful modality for those on anticoagulants, those with pacemakers and those allergic to anesthetics
Cryosurgery DO NOT FREEZE • If you do not know diagnosis • Recurrent skin cancers • Melanoma or any possibility • Morpheaform BCCA • Lip neoplasms • Nasolabial fold cancers • Compromised circulation
Cryosurgery BE CAREFUL ABOUT FREEZING • Lesions on/near the eye • Lesions on the fingers/elbows • Lesions over shins, ears, genitals • Lesions near nails
Cryosurgery BE CAREFUL ABOUT FREEZING • Patients with dark skin • Patients with Raynaud’s disease • Patients on chronic steroids • Patients with diabetes • Patients with cold induced urticaria/cryoglobulinemia
Cryosurgery: Side Effects Short term: • Pain and erythema • Blister formation • Hemorrhage • Infection • Pyogenic granuloma
Cryosurgery: Side Effects Long term • Nerve damage • Pigmentary changes • Hypertrophic scar formation • Permanent nail dystrophy • Recurrence of lesion • Multiple visits may be needed
Electrosurgery • Purpose: • Destroy tissue • Excise tissue • Coagulation • Often done with curettage
Electrosurgery • Electrocautery: Hot electrode (vs cold electrodes) • Electrodessication: Electrode inserted into/on skin (“dries out” skin; “epilation” = fine dessication) • Fulguration: Electrode held away from skin (“fulgur” = lightening; shallow destruction and eschar) • Electrocoagulation: Used for hemostasis • Electrosection: Used to cut tissue • Radiosurgery: Electrosx. with radio frequencies
Electrosurgery • Electricator • Hyfrecator • Bantam Bovie • Ritter Coagulator • Surgitron
Electrosurgery • Advantages: Easy to use, rapid, useful, hemostasis while cutting, less infection • Disadvantages: Electric shocks and burns/fires, hypertrophic scars, “channeling” nerves, viral shedding, delayed bleeding, slower healing, histological distortion • Costs: $1000-2000
Electrosurgery IndicationsProcedure • Cherry angiomas dessication • Achrocordans dessication/fulguration • Telangiectasias dessication • Small verrucae on hands fulguration • Pyogenic granulomas fulguration • Seb Keratoses fulguration • Small BCCa or SCCa fulguration and curettage
Electrosurgery • Start at low power and increase slowly • Use lowest power needed for tissue destruction/cutting
Electrosurgery • Local anesthesia: EMLA, lidocaine • Avoid ethyl chloride, alcohol wipes, and oxygen • Keep field dry (Aluminum chloride) • Mask and ventilation • Fire extinguisher
Electrosurgery and Curettage (C&D) • Useful for small BCCa or SCCa • Local anesthetic • Sharp 2 mm, 3 mm curettes • Scrape in different directions until “firm”
Electrosurgery and Curettage (C&D) • Electrodessicate base and 2 mm skin • Repeat total of three times • Control bleeding with Monsel’s solution • Wound instructions and saucerization
Electrosurgery vs Cryosurgery • Verrucae and AK’s- Cryosurgery • Condyloma- Electrosurgery (Transmission of HPV through vapors)
Electrosurgery vs Excision • Excision preferred for histology and to minimize tissue destruction • Electrosurgical excision acceptable at times • Avoid both on feet if at all possible
Electrosurgery and .... • Pacemakers • Metal pins • Melanoma
Conclusions • Cryosurgery and elctrosurgery are safe, effective and can be done quickly • Know the diagnosis first • Perform patient education before the procedure