2. It is the process of rapidly freezing tissue by exposing
it to intensly low tempratures.
Cryosurgery works by taking advantage of the
destructive force of freezing temperatures on cells.
At low temperatures, ice crystals form inside the cells,
which can tear them apart.
More damage occurs when blood vessels supplying the
diseased tissue freeze
2
4. USES OF
ICE THERAPY
Reduces pain.
Reduces muscle spasm.
Reduces swelling.
Promote repair of the damaged tissues.
Provide excitatory stimulus to inhibited muscles.
4
5. Greek word“kryos” means frost
Local application of low temperature was first used by egyptians for
pain relief, then during franco-american war for amputated limbs
James Arnott, in 19th century, stated that a very low temperature will
arrest every inflammation which is near enough to the surface.
The first cryogens were liquid air and compressed carbon dioxide
snow. Liquid nitrogen became available in the 1940s and currently is
the most widely used cryogen.
In 1961, Cooper and Lee developed the first cryotherapy probe system,
involving the circulation of liquid nitrogen through a closed metal tube
placed in direct contact with the target tissue.
7. Liquid nitrogen
Common method, The super-cooled liquid may be sprayed
using cryogun on the diseased tissue, cryoprobe, or simply
dabbed on with a cotton or foam swab.
Carbon dioxide
Less frequently, doctors use “carbon dioxide snow" formed into
a cylinder or mixed with acetone to form a slush that is applied
directly to the tissue.
8. Argon
Recent advances in technology have allowed for the use of argon
gas to drive ice formation using a principle known as the Joule-
Thomson effect. This gives physicians excellent control of the
ice, and minimizing complications using ultra-thin 17 gauge
cryoneedles.
Dimethyl ether – propane
A mixture of dimethyl ether and propane is used in some
preparations such as Dr. Scholl's Freeze Away. The mixture is
stored in an aerosol spray type container at room temperature
and drops to −41 °C when dispensed. The mixture is often
dispensed into a straw with a cotton-tipped swab.
9. The apparatus consists of a container in which the pressurised
refrigerant media (gases) are stored as liquid gases.
It generates liquid nitrogen at temporature of -196*c
Other refrigerants are carbon dioxide, nitrous oxide, & freon which
may reach temprature of -20* to –90*
A probe is connected to the content to the tube
This probe is applied on the region of the abnornal tissue
Time depends on temprature, size of lesion & type of tissue
Freezing & thawning are done alternatively as many times as
necessary for the lesion
This process destroyes the tissue
9
10. There are two systems and both require a
cryogen.
1. Open system: It involves direct application by
cotton pellets or as spray, the heat is released
by vaporization due to drop in temperature.
Used when no control over depth is required
2. Closed system: This is based on three
principle thermoelectric, evaporative and Joule
Thomson effect. Used when depth orientation is
required.
12. Probe freezing: It is done by direct application of a probe tip
to the lesion. The cryogen circulates through the probe tip
and super cools it, when allowed to contact the target tissue.
In contact freezing, firm contact is made between the cryoprobe and the target
tissue.
While in penetration freezing probe penetrates the target tissue, providing
a large area of direct contact.
Spray freezing: It is done by direct application of the liquid
nitrogen to the tissue and is the most destructive method.
Liquid nitrogen is delivered to the target tissue at such a
volume and velocity that it evaporates at the edge of the
lesion.
13. • The application of liquefied N₂0 sprayed directly
on the skin will bring temperature fully under
control (nitrous oxide always evaporates at (-
)127⁰
• Sophisticated micro-applicator technology enables
an unprecedented level of accuracy of treatment
from 1mm. The prevention of trauma to
surrounding tissue will assure patient’s comfort
• The pressure of the spray at 721 psi will give
maximum control over depth of freezing and will
guarantee the results of the treatment.
14.
15. • The penetration of the ice crystal into the lesion as a result of cryosurgery with the CryoProbe will go
faster and deeper with minimal surface trauma.
• The freezing rate of CryoProbe is 1mm
per 5 seconds
• Depth of treatment: the CryoProbe freezes up to a maximum 5 mm cell structure
16. Very cold gases are then passed through the needles, creating ice balls that destroy
the gland(tumor).
18. The destructive effect of freezing tissue has been categorized into
two major mechanisms
Immediate cell destruction
Delayed cell destruction
Direct effects
Indirect effects
19. 1. Ice crystal formation:
Rapid cooling causes formation of ice crystals from
intracellular and extracellular fluid resulting in physical
disruption of cell
2. Thermal shock:
Damage of cell membrane due to freezing occurs and this
alters cell permeability leading to cell death.
21
20. 3. Cellular dehydration and electrolyte disruption:
Initially during freezing the extracellular fluid alone forms ice which is
limited by intracellular fluid and there is increase concentration of
electrolyte in the extracellular fluid this causes movement of intracellular
fluid to extracellular spaces where they again form ice crystals.
This results in dehydration of cell, cell shrinkage, intracellular increase in
electrolyte which is toxic to the cell and all together causes’ cell death.
22
21. 4. Enzyme inhibition:
Each enzyme requires particular temperature for their
functioning which when altered prevents their function.
5. Effect on proteins:
During the phase after cooling when the cells return to normal
temperature imbibes more water as it has high concentration
of electrolyte which result in swelling and rupture
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22.
23. 1. Vascular effect:
Ischemic necrosis results due to vascular thrombus and
micro-thrombus formation.
2. Immunological effect:
Massive release of pathological cell antigen occurs making
them susceptible for host surveillance mechanism.
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25. o Temperature
o cooling rate
o Thawing rate
o Freeze duration
o Repetitive freeze- thaw cycle
26. Cooling rate
• In cryosurgery, rapid cooling rate i.e. more than
500C/min produces intracellular ice- crystals which is
more destructive
• Such higher rates of cooling can only be achieved close to
the cryoprobe
Temperature
• Mazur stated that the lethal temperature range is between
-50C to -500C.
• The treatment of tumor requires a tissue temperature at
which all the abnormal cells are certainly dead.
27. Thawing rate
• Thawing rate should be slow and continued for longer time
period; rapid thaw rates allow cell survival.
Repetitive freeze- thaw cycle
• Rapid freezing and slow thawing do not guarantee effective
cell destruction.
• Use of repeated freeze-thaw cycle is also beneficial in
treatment of cancerous tumor
28.
29. Benefits of Cyrosurgery in Veterinary Medicin
Minimal/Painless
No open wounds – No Bleeding
No suturing
No general anthesia – safe for older
Rapid treatment time – only seconds
Pinpoint Accuracy
Less discomfort ,no hospitalization/minimal post op care.
Predictable, low tissue damage.
Minimal or no scarring.
Can be an adjunctive therapy with surgery or radiation therapy in
malignancy.
Safe, easy to perform, inexpensive.
30. 1.Healing is slow
2. In lesions of the tongue the procedure can limit its function.
3. Volume of lesion can be beyond capacity
4. Extensive lesions are difficult to treat.
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31. Disadvantages of Cryosurgery
As with the advantages of cryosurgery, the disadvantages can also be categorized into those for the clinician and
those for the patient.
Disadvantages for the clinician include the following:
Liquid nitrogen needs to be delivered and stored. A liquid nitrogen generator may be purchased. If that is not
done, nitrous oxide tanks or other supplies will need to be replenished as needed.
The clinician must be certain of the diagnosis because no tissue will be sent for pathology.
Cryosurgery is not as accurate as a scalpel or laser in cosmetic work.
Disadvantages for the patient include:
Erythema and swelling are the norm. Blistering is common.
May require multiple visits.
Hypopigmentation.
Damage to adjacent structures such as joints and bones may lead to lameness and fracture.
Risk of uncontrolled freezing - resulting in destruction of normal tissue.
32. Accurate Pinpoint Precision, Freezing Power
and Pressure with the touch of your Fingertip!
Manufacturers have devised various metal
attachments to serve as heat-conducting probes
for cryotherapy. Copper, because of its high
conductivity, is typically used
33. CryoProbe’s different micro
applicators tips allow pinpoint
accuracy to treat skin lesions from
1mm to 8mm in size!
Blue dot applicator
Applications 1-3 mm
White dot applicator
Applications 2-4 mm
Green dot applicator
Applications 3-6 mm
Yellow dot applicator
Applications 4-10 mm
34. Simple pencil type grip for easy use .
Very accurate application .
Freezes to -89ºC and to a depth of 3mm .
Interchangeable ‘contact’ heads for special applications
including GUM, Podiatry & Dermatology .
Avoids all of the storage and transport problems associated with
traditional cryotherapy
Once a cylinder has been attached CryoAlfa can be kept in a
drawer without degradation of the N20 contents for
approximately 3 months .
Can be easily transported for use in home visits .
The level of cold generated can be adjusted by the rate at which
the button is depressed.
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35. With the CryoProbe you will be able to treat (but not limited) to the following lesions successfully:
• Adenomas
• Epuli
• Pappilomas
• Granulomas
• Warts
• Small Sarcoids
• Eye Lid Tumors
You will be able to quickly and easily treat skin lesions that you could not treat before without
undesired side effects!
43. 1. Cold urticarial patient develop redness and swelling in the skin
2. Cryoglobulinemia, abnormal blood protein results in gel formation
resulting in ischemia or gangrene
3. Raynaud’s phenomena
4. Paroxysmal cold hemoglobinuria,hemoglobin is released from
lysed red cells and is excreted in urine
5. Peripheral vascular disease
6. Patients undergoing immunosuppressive therapy
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45. Cryotherapy is an effective treatment method for a variety of lesions of the
head and neck region. It is advantageous over surgery and is well accepted
by patients.
Many a times it is used when the conventional therapy either fails or is
contraindicated. But unless the physician is confirmed of the diagnosis and
volume of lesion it is not advisable to use it.
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46. 1. Cryosurgery – a practical manual – paola pasquali
2. Web
3. Cryotherapy- a novel treatment modality in oral lesions- international
journal of pharmacy and pharmaceutical sciences. Issn- 0975-1491 vol 5,
suppl 4, 2013
4. Reade pc. Cryosurgery in clinical dental practise.Int dent j 1979;29:1-
11.
5. Leopard pj. Cryosurgery and its applications in oral surgery. Br j of oral
surg 1975;13:128-52.
6. Orpwood rd. Cryosurgical apparatus. In: bradley pf, ed , cryosurgery of
maxillofacial region. Vol.1.Boca raton, florida: crc press, 1986.
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