When you have a twisted ankle, you head to the freezer and grab ice - Do you wonder why we use ice? Ice can reduce swelling and may even reduce the pain you feel. 

Over the years, the idea of ‘applying cold temperature’ and its benefits have been researched. Applying ‘cold’ was first described in the 19th century. From the early 19th century to the mid-19th century, people went from describing the benefits of using cold temperatures to introducing liquid nitrogen for clinical use.¹

 ‘Cryosurgery’ sparked interest in 1961 when the cryosurgical probe was introduced - the basis of liquid nitrogen flowing through a tube to freeze tissues, with animal and clinical studies demonstrating the potential benefits of freezing.¹ Over time, clinical research has developed modern methods, making the procedure minimally invasive for clinical use.⁵  

Definition

Cryosurgery is a type of surgery that uses controlled cold temperatures to cause tissue destruction for therapeutic benefit.¹ Cryosurgery can also be referred to as cryotherapy and cryoablation.² Cryosurgery uses controlled cold temperatures produced by liquid nitrogen, carbon dioxide, or argon gas. ^1,2,3 Liquid nitrogen is used commonly because a very low temperature can be attained, as low as around -197°C.⁴ 

Basics of cryosurgery³

As mentioned, cryosurgery uses ‘extreme’ cold temperatures; the most common agent used to produce this low temperature is ‘liquid nitrogen’. 

Liquid nitrogen can be administered through a probe, allowing direct application to the designated area. Cryosurgery targets and exposes the designated area (i.e., pre-malignant, malignant, and benign lesions) to controlled cold temperature for tissue damage. Tissue damage is stimulated to remove the unwanted designated area.  

Tissue damage occurs in two ways: 

• Tissue ischemia, meaning inadequate blood supply to cells, damages blood vessels and capillaries in the designated area - cells in the designated area ‘die’
• The second way is by the formation and thawing of ice crystals, which damage cells in the designated area, resulting in cell rupture

Applications of cryosurgery

Cryosurgery can be recommended as a treatment in different specialties to remove unwanted tissue, whereas in some cases, it uses the ‘application of freezing’ to heal tissue. 

Dermatology^3,6

Cryosurgery is a treatment that is a fast-delivery solution for many skin conditions that can lead to good cosmetic outcomes. The surgery is performed in an outpatient setting, meaning patients can leave the same day after the procedure and may not require an overnight stay. 

Cryosurgery can be used to treat benign lesions (skin lesions and warts). For example: 

• Seborrheic keratosis
• Verruca
• Skin tags
• Molluscum contagiosum
• Solar lentigo
• Hypertrophic/keloid scars
• Genital warts

This method can also be used to treat precancerous and cancerous lesions. 

For example:

• Actinic keratosis
• Basal cell carcinoma
• Non-invasive squamous cell carcinoma

Side effects or complications can be immediate, prolonged, or delayed. You may experience complications that can include pain, bleeding, blistering, headache, hypopigmentation/hyperpigmentation, alopecia, and scarring. 

Ophthalmology

Wondering how we process visual pictures? The retina within your eyes. The retina is a layer of specialised cells at the back of your eye that works like a ‘digital camera’ that processes light to form images. Light is detected by the retina, and then signals are transmitted to the brain via nerves (like messengers) to process the images.⁷

Cryotherapy is used as a treatment for: 

• Retinal detachment repair. This is when the retina becomes pulled away from its position at the back of the eye - referred to as retinal tear/detachment.⁸ Cryotherapy is a treatment option to heal any tears in the retina.^8-9 While the procedure does not remove unwanted tissue, the 'freezing method' helps the retina seal back into its position. 
• Coats’ disease.¹⁰

Cryosurgery involves the freezing of cancer cells to induce cancer cell death ¹¹. It is a treatment option for certain eye tumours: 

• Retinoblastoma¹¹
• Squamous cell cancer of the conjunctiva¹²
• Basal cell cancer and squamous cell skin cancer around the eye¹²

Side effects or complications can include blurry vision until recovery, soreness, and redness.⁹     

Oncology

• Cancer treatment: cryoablation can be offered as a treatment option for solid tumours. This treatment is offered when patients have a small tumour, as an alternative when surgery is not a suitable approach, or potentially after cancer relapse after primary treatment (e.g., radiotherapy). For instance, in bone, breast, liver, lung, kidney, and prostate cancer.^2,13,14,15

Side effects or complications can include pain, bleeding, and infection.²

Gynaecology

• Cryosurgery can be offered as a treatment to remove pre-malignant lesions in the cervix - referred to as cervical dysplasia or cervical intraepithelial neoplasia.¹⁴

Side effects can include similar pain to period, cramping, and bleeding.^2,14

Cryotherapy: general overview of the procedure and techniques^2-3,14

• Patient preparation for cryosurgery happens during outpatient consultation with a healthcare practitioner, doctor, or dermatologist. CT or ultrasound examination may be performed to identify positions for certain conditions (e.g., cancer)
• Depending on where the treatment is required, local or general anaesthesia may be administered  
• For conditions outside, i.e., skin conditions, liquid nitrogen can be placed directly by a spray or cotton swab. For tumours or lesions inside the body, a cryoprobe is used whereby nitrogen flows through a tube and is placed towards the designated area
• The process of freezing and thawing is monitored and controlled
• Depending on the conditions treated by cryosurgery, the side effects can range from mild to severe

Advantages of cryosurgery 

The following advantages of cryosurgery are:^2,6,14

• Treatment often occurs in outpatient settings 
• Effective alternative to more invasive procedures 
• Can be delivered quickly 
• Cost-effective 
• Safe 
• Low cost 
• Minor incision/puncture - minimally invasive 
• Controlled to only designated areas 
• Available as an alternative treatment option 

Limitations and potential risks

• Generally, the most common side effects are pain and swelling. 
• Different complications can occur depending on the area treated and can vary from immediate, prolonged, and delayed. 

Ask a health professional to know more about side effects and complications in the areas you are being treated. 

FAQ’s

What is the cryosurgery used for? 

Removes unwanted tissue using controlled cold temperature. 

How painful is cryosurgery? 

Not generally painful, but pain can vary from mild to severe. Depending on the area being treated, individuals are administered local or general anaesthetics, which should help relieve any pain symptoms. 

Who needs cryosurgery? 

Anyone with benign, pre-malignant, and malignant lesions. Other reasons can include when other treatments are not a suitable approach.

Summary

• Cryosurgery also called cryotherapy/cryoablation, is a minimally invasive procedure that removes unwanted tissue by ‘freezing’ the tissue
• This procedure can be used to treat skin lesions, eye conditions, and benign, pre-malignant, and malignant lesions
• The process involves directly applying liquid nitrogen or through a cryoprobe to freeze cells and stimulates cell death in two ways in the treated area
• Side effects and complications can vary depending on the area being treated
• Health professionals decide whether cryosurgery should be offered to you as a treatment based on several factors