CRYOABLATION
TECHNOLOGY
Cryotherapy FAQ
Frequently Asked Questions on Cryotherapy
Q: What is Cryotherapy?
A: Cryotherapy
is the application of extreme cold to freeze and
destroy tumors.
Q: How does the ice form?
A: Galil Medical's patented freezing technology is based on the Joule-Thomson effect to produce extremely low temperatures. As compressed Argon gas passes through the cryoablation needle, the tip is cooled, forming an iceball, which engulfs and destroys the tumor.
Q: What is the Joule-Thomson effect?
A: The change in temperature that accompanies expansion of a gas without production of work or transfer of heat. The cooling occurs because work must be done to overcome the attraction between the gas molecules as they move farther apart.
Q: How does the ice kill cancer cells?
A: The basic features of cryosurgical ablation have been established as rapid freezing, slow thawing, and repetition of the freeze–thaw cycle. At sub-zero temperatures, ice crystals first form outside the cell, causing shrinkage and damage. As the temperature continues to fall, intracellular ice forms causing additional injury to the cell. During the thaw cycle, the ice melts and water enters the cell causing expansion and further disruption to the cells. All the parts of the freeze–thaw cycle contribute to tissue injury.
Q: What is meant by the freeze-thaw cycle?
A: Cryotherapy ablation begins with a freeze cycle lasting approximately 10 minutes. This is followed by several minutes of thawing, whereby the cryoablation needle is warmed resulting in a thawing of the target tissue. Thawing is a prime factor in the destruction of cancer cells. The freeze-thaw cycle is then repeated as it is known to be an important factor in effective ablation treatment.
Q: For what tumors is cryotherapy appropriate treatment?
A: Cryotherapy has applications for a range of cancer treatments in addition to treatment for benign or non-cancerous tumors. There is a wealth of clinical data on prostate cancer and renal cancer cryo treatments. Additional studies have been done on cryosurgical treatments for liver, thoracic, and bone tumors, as well as benign breast fibroadenoma.
Q: Is it painful?
A: Actually, ice is a natural pain reliever. Patient experience with cryoablation shows minimal pain.
Q: How long has cryo been used as a cancer treatment?
A: The first modern physician to utilize the cryosurgery (freezing) technique was Dr. James Arnott of Brighton, England in the mid 1850’s. Arnott observed the shrinking of tumors and pain relief after using salt solutions containing crushed ice to freeze breast, cervical, and skin cancers. Arnott also recognized the numbing effects of cold, recommending the use of cold as an anesthetic before surgery.
Q: How is today’s cryotherapy equipment different from the earlier generations?
A: Major innovations include the use of advanced
gas expansion method (Joule-Thomson principle),
small
diameter needles, and support for monitoring
using ultrasound, CT or MRI imaging. These advancements
have contributed to significant improvement in
controlling the freezing process and allowing
cryosurgery to be offered as a minimally invasive
procedure.
Q: What is meant by minimally invasive?
A: Minimally invasive surgery provides an alternative to open invasive surgery. Minimally invasive procedures are performed through the skin or through an anatomical opening, which usually result in shorter hospital stays, and may allow outpatient treatment.
Q: Why is cryoablation considered minimally invasive surgery?
A: Cryoablation is performed using 17-gauge
(1.47 mm) needles inserted percutaneously,
directly through the skin, with no need for incisions.
Long-term data suggests that prostate
cryotherapy delivers disease-free rates comparable
to radical prostatectomy and radiation, with the
benefit of lower rates of incontinence, shorter
recovery periods and relatively minimal complications.
For small renal carcinoma, cryotherapy is gaining
acceptance as an effective alternative to surgery.
Intermediate-term outcomes for renal cryotherapy
show excellent clinical results, reduced morbidity
as well as recovery time compared to other minimally
invasive treatment modalities including radiofrequency
(RF) ablation and microwave ablation.
Q: Who performs cryosurgical treatments?
A: Urologists routinely perform prostate
cryoablation and renal
cryoablation. Interventional radiology (IR)
departments usually perform image-guided cryoablation,
although there are several general surgeons and
thoracic surgeons who are cryotherapy specialists.
Q: How long has Galil Medical been in business marketing cryotherapy products?
A: Galil Medical was founded in 1996.
Q: Where are Galil Medical’s offices located?
A: Galil Medical with R&D and manufacturing facilities are located in Yokneam, Israel. Dedicated sales offices are located in Arden Hills, Minnesota and London, England.
Q: Who are the investors in Galil Medical?
A: Shareholders include Thomas, McNerney & Partners, Vertical Group, Investor Growth Capital, Elron Electronic industries (NASDAQ:ELRN) and RDC Rafael Development Corporation, Ltd.
Q: What clinical studies are currently being supported by Galil Medical?
A: Galil Medical is currently conducting a clinical
study on nerve-sparing
cryoablation for prostate cancer and a postmarket
study on cryoablation for the treatment of benign
breast fibroadenoma.
Q: Specifically how does Galil Medical’s system differ from other cryotherapy systems?
A: Galil Medical continuously strives to improve
cryoablation procedure precision and control.
The company’s innovative 17-gauge
cryoablation disposable needles are the smallest
diameter available on the market. They have been
shown to minimize the risk of damage to tissue
during minimally invasive surgery, while thermal
sensors, positioned in critical areas, provide
real-time, continuous temperature monitoring.
Support for concurrent freezing of multiple cryogenic
needles produces large iceballs, enabling treatment
of large volumes and simultaneous ablation of
multiple tumors.
Q: What is a 17-gauge cryoablation needle?
A: The 17-gauge
needles are 1.47mm in diameter, about the
size of a biopsy needle. A flexible range of needles
is available and each needle produces different
shaped and sized iceballs. The full range of 17-gauge
cryoablation needles are disposable and feature
a sharp, cutting tip for easy, percutaneous insertion.
Q: Why are the thermal sensors separate needles?
A: The 17-gauge
cryoablation needle family is used in conjunction
with 17-gauge thermal sensors or multi-thermal
sensors for continuous, real-time temperature
monitoring. The thermal sensors are usually placed
to confirm that the boundaries of the tumor have
been frozen and that adjacent healthy tissue has
not been damaged. The previous generation of large
probes included a thermocouple within the probe
for temperature monitoring.
Q: What is a cryoprobe?
A: Cryoprobes are large diameter cryosurgical instruments available in various diameters (2mm, 3mm) tailored for specific applications. A thermocouple in the tip provides temperature measurement.
Q: What other clinical applications is Galil Medical developing besides prostate cancer and kidney tumor treatments?
A: Galil Medical’s innovative cryosurgical
ablation treatments have been widely used
by urologists worldwide for prostate and kidney
cancer. Building upon this success, the company's
next generation of cryotherapy applications are
aimed toward providing minimally invasive treatments
for the Women's Health and Interventional Radiology
markets.
Q: I have read about cryomyolysis for uterine fibroids. Is the procedure available?
A: This treatment is considered experimental and is not available in the United States. Studies are currently evaluating cryo as an alternative to hysterectomy for symptomatic uterine fibroids.
Q: I have heard about freezing breast fibroadenomas. Is this procedure available?
A: As an alternative to conventional surgical removal for benign breast fibroadenomas, cryotherapy ablation offers a short 30 minute office procedure with minimal to no scarring. Galil Medical is currently conducting a postmarket study in the U.S. on using cryoablation for the treatment of breast fibroadenoma.
Q: How does the doctor see what is going on during cryosurgery?
A: Different cryo procedures are performed under different visualization. Some procedures are performed laparoscopically, also referred to as minimally invasive keyhole surgery. A tube with a light and a camera lens at the end is inserted through small incisions in the abdomen. Imaging modalities, including ultrasound, CT and MRI are used by the physician to guide the needle placement as well as monitor the freezing process. In ultrasound-guided cryoablation procedures, the tip of the cryoablation needle is highly echogenic and is clearly visible. In CT-guided and MRI-guided procedures, the iceball is very clearly visualized on the imaging modality.
Q: What is the SeedNet™ System and how does it work?
A: The SeedNet™
system is a cryoablation system that enables
minimally invasive treatments for various clinical
applications in both inpatient and outpatient
settings. Integration with ultrasound or CT enables
a high level of control for cryoablation needle
placement and positioning, iceball formation and
the freezing process. Computer-controlled freeze
and thaw are administered via patented, 17-gauge
cryoablation needles. Easy percutaneous insertion
provides the flexibility to simultaneously ablate
multiple tumors, or large lesions in a single
cryosurgical procedure.
Q: What is the Presice™ Cryoablation System and how does it work?
A: The Presice™
Cryoablation System is a computer-controlled
system designed to aid physicians in performing
minimally invasive procedures. The Presice™
system is operated using high-pressured Argon
gas supplied from an external gas source connected
to the Workstation. Gas flow from the cylinders
to the needle tips is controlled by the Presice™
software. The freeze and thaw processes, based
on the Joule-Thomson effect, are administered
via patented, ultra-thin 17-gauge (1.47 mm diameter)
cryoablation needles. A range of i-Thaw™ and Helium
Thaw needles are supported.
Q: What new features does the Presice™ system have as compared to the SeedNet™ system?
A: Innovative features include i-Thaw™, MTS and
IceVue™. The i-Thaw™ mode supports the use of
Argon gas for both freeze and thaw, eliminating
need for Helium tanks. Patented multi-point thermal
sensors (MTS) record temperatures throughout the
gland, or tumor, for a high level of procedure
control. The
IceVue planning software enables preoperative
simulation of the cryoablation procedure and automatic
suggestion of needle placement to ensure accurate
clinical outcomes.
Q: How exactly does the IceVue software assist the physician?
A: The
IceVue™ planning software is a tool for the
physician to pre-plan the cryoablation procedure.
By connecting to any ultrasound system, the planning
can be executed on a real-time mage (prostate
only). The Auto-plan feature calculates and displays
system recommended positioning for each cryoablation
needle on a captured ultrasound image. Alternatively,
virtual cryoablation needles can be manually placed
and the ablation coverage simulated. The resulting
isotherm map shows the simulated outcome of the
freezing effect and can be adjusted to achieve
maximum coverage of the target.
Q: How are MTS different from regular thermal sensors?
A:
The multi-point thermal sensors provide four (4) independent temperature readings. In addition, in the Presice™ graphical user interface, temperature targets can be set and visual warnings are displayed during the procedure to alert the physician to take appropriate action.
Q: The cryotherapy machines use Argon and Helium gases. What are they? Are they dangerous?
A: Both gases are harmless. Helium (He) is colorless, odorless and non-toxic, most known as the gas that is used for children's balloons so that they stay up in the air. Argon (Ar) is colorless, odorless and non-toxic, known as the gas used in air conditioning systems.
Q: Does the gas enter the body during treatment?
A: No. The 17-gauge
cryoablation needle is a sealed needle.
Q: How does a cryotherapy treatment work?
A: One or more ultra-thin, 17 gauge (1.47 mm) cryoablation needles are inserted percutaneously (through the skin) directly into the tumor, with no incision. Once inserted into the tumor, the cryoablation needles are cooled to sub-zero temperatures according to a predetermined freezing and thawing protocol. The physician sculpts a freeze zone to engulf and destroy the cancerous area, whether it is the entire prostate gland, kidney tumor or other tumors. Depending upon the treatment, ultrasound, CT and/or MRI Imaging continuously monitors the iceball propagation and ice coverage of the tumor.
Q: Do CT-guided procedures require special equipment?
A: No, however Galil Medical has developed a cryoablation needle with a 90 degree handle especially for use with CT image guidance.
Q: Do MRI-guided procedures
require special MRI-compatible equipment?
A: Yes. Only specially designed MRI-compatible
equipment may be used within MRI rooms. The MRI
SeedNet™ is a stand-alone system, compatible
with all MRI systems (closed or open bore) up
to 1.5T. and features a versatile mobile unit
which is placed within the MRI room, allowing
the Interventional Radiologist, or other physician
access to both the patient and the needles during
the cryoablation treatment. A full range of small
diameter MRI-compatible cryoablation needles are
available for different applications.
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