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Cryosurgery and Electrosurgery
Adam O. Goldstein, MD
Associate Professor
UNC Dept Family Medicine
Chapel Hill, NC
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 time Costs» 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 orCry-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
Indications Procedure 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
Resistant Wart
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
That….that…that….that’s...
That’s all folks!!!!!!!!!!!!!
THE END