Cryotherapy

Following are some of the applications of cryotherapy:

• Cryosurgery: The most important application of cryotherapy used in medicine today, cryosurgery is often used interchangeably with cryotherapy. By freezing and thawing target cells, inflammation and necrosis are produced. It is an effective technique with minimal complications or side effects. Different methods of cryosurgery are available for use, including:
  • Spray technique
  • Dipstick applicator method
  • Cryoprobe
  • Thermo-couple device
  • Forceps technique
• Whole-body cryotherapy: Used as an add-on therapy to enhance overall patient quality of life and wellness, whole body cryotherapy is usually administered by trained physiotherapists. The individual is exposed to cold air between −110°C and −140°C for short periods of time in order to stimulate the circulatory and nervous systems. Special cryogenic chambers and cryo barrels, also known as cryo saunas, are used.
• Non-surgical liposuction or cryolipolysis: Another application of cryotherapy that’s becoming popular is cryolipolysis, in which fat cells are frozen and destroyed using freeze-thaw cycles. These techniques are safe and effective alternatives to the traditional liposuction techniques and have been approved by the Food and Drug Administration (FDA, USA). Commonly-used technologies of cryolipolysis include: 
  • ZELTIQ
  • CoolSculpting
  • Pleasanton
  • Calif

The uses of cryotherapy in medicine, surgery and cosmetic health are wide and varied. Some applications include, but may not be limited to:

Indications for cryosurgery

• Pigmented lesions:
  • Melasma
  • Tattoo
  • Idiopathic guttate hypomelanosis
  • Lentigo
• Vascular lesions:
  • AIDS-related Kaposi’s sarcoma
  • Venous lake
  • Cherry angioma
  • Capillary hemangioma
  • Vascular malformations of blue rubber bleb nevus syndrome
• Cysts and tumours: 
  • Milia
  • Seborrheic keratosis
  • Skin tags
• Skin warts
  • Genital warts caused by the human papillomavirus (HPV) can be removed for better cosmetic results and for enhanced physical comfort.
• Molluscum contagiosum: This is a type of virus-induced skin lesion that usually resolves spontaneously over time. However, the treatment options available include cryotherapy and 5% imiquimod. While 5% imiquimod treatment takes longer to show results; it is preferred over cryotherapy in children as they are more prone to developing skin blisters and bullae following cryosurgery.

Indications for whole-body cryotherapy

Whole-body cryotherapy can benefit a patient as an add-on treatment for disorders of the bone, muscle, joints and tendons. It can also help in disorders that do not stem from a tangible physical problem. Some conditions that can benefit from whole body cryotherapy include:

• Fibromyalgia
• Chronic fatigue syndrome
• Phantom pain and phantom limb syndrome after amputation 
• Chronic pain syndrome
• Osteoarthritis
• Rheumatoid arthritis
• Osteoporosis
• Central nervous system disease or neurodegenerative disease that affects the musculature of the body
• Multiple sclerosis
• Ankylosing spondylitis
• Inflammation of the spine or spondylitis due to other causes like infections (tuberculosis Pott's spine)
• Muscle pain and inflammation
• Depression and mood disorders
• Immune system improvement
• Delayed-onset muscle soreness
• Degenerative disease of the joints and spine
• Inflammation of tendons, bursa or joint capsules

Indications for non-surgical liposuction

Also known as cryolipolysis, this is a treatment that may be sought by healthy individuals who wish to reduce their body fat percentage for a desired cosmetic result and do not have any contraindications to the therapy.

Following are the procedures for the different types of cryotherapy:

Cryosurgery: Cryotherapy is often used interchangeably with cryosurgery, which is the application of cold energy to destroy target cells in a controlled manner. A cryogen, or source of cold energy into which the heat from target cells is transferred, is used. Liquid nitrogen is the most commonly used and preferred cryogen. Other cryogens available include Freon, carbon dioxide and nitrous oxide, but they are not used often as they are not as effective. Before beginning the procedure, the doctor informs the patient about the steps that will be taken, answers any questions, addresses concerns and then takes written informed consent to proceed further. A topical local anaesthetic like 1% lidocaine can be used in larger lesions in adults and is always used while treating young children. After numbing the area to be treated, the excessive keratin and skin material may be debulked by a razor, number 11 surgical blade or curette. Following the preparation, the cryosurgery may be conducted by following one or more of the following techniques:

• Spray technique: The nozzle tip of the spray gun is held about 1 cm from the treatment site and liquid nitrogen is sprayed on the lesion until an ice ball forms. The doctor palpates the lesion to determine the size of the ice ball created. This process is repeated until an ice ball of the desired size is created. The time for which the lesion is frozen is the freeze time. This freeze-thaw cycle can be repeated, depending on the type of lesion being treated.
• Dipstick applicator method: For smaller benign lesions, a cotton dipstick or swab is used. After dipping in liquid nitrogen, it is placed on the lesion for the desired freeze time.
• Cryoprobe: A thin layer of white petrolatum is applied to the treatment site and then a specialised copper device that absorbs heat is applied to the lesion. This technique is not commonly used.
• Thermo-couple device: A local anaesthetic is injected into the lesion and a temperature probe is also placed at the desired depth in the lesion. Following this, a disposable cone is introduced into the lesion through which the liquid nitrogen is applied from the spray gun. The temperature probe is linked to a digital thermometer, which reports the temperature at the core of the lesion, allowing for precise freezing and preventing damage to surrounding tissue. 
• Forceps technique: In order to prevent collateral damage, forceps are used to deliver the cryogen to the lesion in a concentrated manner.

Whole-body cryotherapy: The individual is dressed in dry socks, slippers, gloves, face masks and earmuffs to protect the more temperature-sensitive tissues. The patient can receive whole body cryotherapy by two means:

• Cryo barrel or cryo sauna: The patient’s entire body is encased in a chamber and exposed to cool air up till the level of the arms produced by liquid nitrogen. The patient is exposed to extremely cold air at around −100°C for a few minutes and then allowed to emerge.
• Cryogenic chambers: The patient is allowed into room-like chambers with cold air being pumped in by liquid nitrogen powered compressors. The antechamber has temperatures of around – 60°C and leads the way to the main chamber which is maintained at −100°C. It is important to note that the atmospheric air breathed by all humans is 78% nitrogen and, therefore, short-term exposure to cold air in the cryogenic chambers is safe.

The first 5 to 10 whole-body cryotherapy sessions are recommended to be scheduled in close succession, only a few days apart. Afterwards, weekly maintenance therapy can be followed.

Cryolipolysis: By applying the principle of cold energy mediated cell destruction, fat or adipose cells are targeted to reduce fat content in a patient’s body, generally with the aim to improve the cosmetic results. It is performed as an outpatient procedure in the doctor's office. The size and shape of the fatty tissue to be reduced is assessed and the area to be treated is marked with a skin marking pencil. A gel pad is placed to protect the area being treated and then a handheld applicator is applied to freeze the target fat cells. The patients are awake throughout the process and may feel intense sensations of cold, tingling, stinging and aching for the first few minutes, after which numbness sets in. The doctor may massage the area in between to help the fat tissue break down further. The process lasts for up to an hour to target a single problem area.

The presence of certain factors can make cryotherapy (irrespective of the modality being used) imprudent or may warrant modifications to be made or precautions to be taken. Some contraindicating factors for cryotherapy include:

• Relative contraindications: The presence of the following factors necessitates the use of extra caution while administering cryotherapy: 
  • Age above 65
  • Venous thrombosis and a history of peripheral arterial embolism
  • Excessive emotional lability or excitability
• Absolute contraindications: In the presence of the following factors, cryotherapy must not be carried out: 
  • Undiagnosed growth: Cryosurgery must not be carried out on a neoplastic growth that has not been diagnosed clinically, histopathologically or with a dermatoscopy
  • Use of cryosurgery near the margins of the eyes
  • Cold intolerance
  • Cryoglobulinaemia
  • Cryofibrinogenemia
  • Raynaud disease
  • Cold urticaria
  • Open wounds and ulcers
  • Gangrenous lesions
  • Thromboembolic changes and inflammation in the venous system; for example, history of a stroke or heart attack
  • Agammaglobulinemia
  • Central nervous system disease
  • Sympathetic neuropathy
  • Hypothyroidism
  • Local blood flow disturbances
  • Previous history of cold-induced injury at the site or limb
  • Poor circulation at the site or in the limb
  • Significant anemia
  • Mental disorders, which may prevent adequate co-operation with the patient in the whole body cryotherapy chamber
  • Emaciation and hypothermia
  • Cancer
  • Prinzmetal syndrome or variable angina, which can lead to a heart attack by exposure to the cold
  • Unstable coronary artery disease
  • Valve disorders: Aortic valve stenosis and mitral valve stenosis
  • Diseases of the myocardium or the mitral apparatus
  • Arrhythmia at a rate higher than 100 strokes per minute
  • Severe forms of exertional angina pectoris and spontaneous angina
  • Venous blood leaks in the lungs
  • Acute respiratory diseases of various origins
  • Effects of drugs, especially antipsychotics and alcohol

Although an effective tool, cryotherapy-based medical and surgical techniques can be associated with some complications. Cryotherapy, especially cryosurgery, can be associated with various untoward side effects that arise at different times following the procedure. Some common adverse effects with cryotherapy include, but may not be limited to:

• Acute complications: Side effects that occur immediately following treatment
  • Headache
  • Pain
  • Blister formation
• Delayed complications: Side effects that occur a few days following the procedure
  • Hemorrhage
  • Infection
  • Excessive granulation tissue formation
• Prolonged complications: Side effects that persist for an unduly long period of time
  • Milia: Hardened pale white nodule formed over a blocked sweat gland 
  • Hyperpigmentation
  • Change in sensation over the area treated
• Permanent complications: Side effects that cannot be reversed and remain lifelong
  • Alopecia
  • Skin atrophy
  • Keloids 
  • Scarring
  • Hypopigmentation
  • Ectropion formation
• Some possible temporary complications following non-surgical liposuction, which generally resolve within 14 days of treatment, can include:
  • Temporary erythema
  • Bruising
  • Transient numbness

The most common serious side effect that can occur after cryolipolysis is late-onset pain, which can occur 2 weeks after the procedure. No specific treatment is needed as it resolves without intervention.