Effectively managing pain is a problem confronting millions of patients; treatment is complex and often comes with risks, whether surgery or opioids are indicated. At Hudson Medical, we take a sophisticated, multidisciplinary approach to treat pain effectively and expeditiously, and we welcome a new modality in the field of pain management with incredible potential to treat pain: cryoablation therapy.
While the path to pain relief is often rocky, it is important to look toward new technologies that are less invasive and have longer-lasting effects. Where many people don’t respond to conventional methods of pain relief, improved pain control regimens have been using new approaches that can further reduce the need for opioid analgesics.
Cryoablation is an innovative procedure that applies extreme cold to destroy or inactivate tissue. This medical technique has been used to kill cancer cells, correct an irregular heartbeat, and most successfully, relieve pain. For the latter, surgeons have exploited the mechanism behind cryoablation — which is theoretically similar to applying cold to numb, or anesthetize, a body part — as an agent to block nerve pain.
As a cutting-edge health facility, Hudson Medical sees nerve cryoablation as an attractive option for patients suffering from chronic pain. Though rather new, cryoablation can provide better pain control than some traditional thermal radiofrequency ablations.
What Is Nerve Cryoablation?
Put simply, cryoablation for treating pain is a procedure in which the physician freezes the peripheral nerve responsible for transmitting pain signals to your brain. It involves the precise localization of the offending nerve. Cold temperatures applied to the tissue then damage it enough to interfere with pain signals, effectively shielding the brain from experiencing pain.
Along with the peripheral nerves indicated in pain, at Hudson Medical, the most common targets for cryoablation treatments include the genicular nerves for chronic knee pain, medial branch nerves for arthritis of the spine, and occipital nerve ablation for headaches.
In a cryoablation procedure, a thin, hollow needle called a cryoprobe is inserted into the skin and advanced toward the offending nerve under X-ray or ultrasound guidance. CO2 gas is then pumped through a tiny nozzle on the end of the hollow needle, which freezes the needle tip to -80 degrees Celsius and is used to selectively numb a section of the nerve.
This may not be a permanent solution to pain control, but it is safe and can provide relief for 6-12 months and even longer in many cases. Cryoablation can be repeated if the pain returns (and as the nerve regenerates).
How Does Cryoablation Work?
Cryoablation is an outpatient procedure performed in an operating suite while the patient is under minimal sedation for their comfort. The surgeons will locate the target nerve and treat it with extreme cold, effectively freezing the nerve and blocking it from transmitting pain.
Identifying the Target
Perhaps the most important step of a cryoablation procedure is to single out the nerve responsible for signaling pain. Common x-ray or ultrasound technology is most often used to identify the suspected site of pathology, but in some cases, a nerve stimulator is required to detect the offending nerve.
Positioning the Cryoprobe
After localizing the target nerve, the cryoprobe is inserted. Under imaging guidance, the hollow needle is advanced toward the previously identified nerve or pathology. Usually, CO2 gas is delivered through the center of the needle, drastically lowering the temperature around the targeted nerve (as low as -80 degrees Celsius).
Cryoablation Freeze Cycle and Size
Once in position, appropriate freeze and defrost cycles are initiated. The probe temperature is initially lowered to -80 degrees Celsius for a 2-minute period. A passive thaw cycle is undergone following the freeze cycle. The freeze/thaw cycle is usually repeated several times during a session. Each cycle increases the degree of nerve disruption: after adequate thawing, the subsequent freeze cycle serves to decrease temperatures at sites further from the probe, increasing the size of the freeze zone.
Recovery and Side Effects
The procedure can take up to 40 minutes, depending on the area being treated. Patients may feel pain or discomfort as the surgeon proceeds to localize the offending nerve, and some patients report a burning sensation for the first 30 seconds of the initial freeze cycle; however, the rest of the procedure has been described as totally painless.
For a week or two following cryoablation, the patient may experience muscle spasms due to tissue contact with the freezing cryoprobe. That said, it is safe for people to return to their regular activities one to three days after the procedure. The process can be repeated as needed, and there is no evidence of permanent neurologic damage as a result of multiple cryoablation procedures.
What Is the Mechanism of Nerve Injury in Cryoablation?
The target of nerve cryoablation therapy is actually the protective myelin layer surrounding the nerve. Damage to the myelin sheath is sufficient for interrupting pain signals to the brain. The myelin sheath allows for nerve impulses to be quickly transmitted along the long nerve axons; freezing the myelin proteins causes their breakdown, stopping the pain signal in its path.
In other words, without its protective sheath, the nerve can no longer communicate with the brain. The nerve will eventually rebuild myelin, which is why cryoablation is not considered permanent and may need to be repeated.
While low temperatures cause demyelination, nerve freezing further causes ice crystals to damage the small blood vessels supplying the nerve (called the vasa nervorum) leading to the degeneration of targeted nerves. In some cases, the process of regeneration can correct the original pathology.
How Has Cryoablation Changed the Focus of Pain Relief?
Pain can be the result of disease, physical injury, and inflammation. Inside the body, if sensitive tissue is hit during a procedure, it can cause nerves to misfire — the pain pathway once established is often permanent. Usually, it’s too dangerous to remove the offending nerve, it can even be fatal, and the option to freeze it is far more desirable.
Historically, pain treatments focused on spine and spine pathology rather than on the nerve itself. However, a renewed spotlight on the role of peripheral nerves in causing pain is paralleled by a renewed interest in cryoablation therapy for long-term pain management. To be sure, cryoablation is indicated for deep nerves as well as for various nerve pathologies such as neuromas (pinched or compressed nerves) and entrapment of peripheral nerves.
Left untreated, both neuromas and entrapment of peripheral nerves can develop into significant and debilitating problems, including peripheral neuropathy and complex regional pain syndrome. A simple injection of extreme cold can draw rapid, lasting relief. Cryoablation may even help correct the original pathology: as the nerve regenerates, entrapment does not occur again.
What Role Does Cryoablation Have in Modern Pain Management?
Using cold for pain relief has been documented in ancient civilizations, including by Hippocrates in Greece and by ancient Egyptians. Many descriptions of cryoanalgesia are reported throughout history in which tissues were treated with extreme cold for an anesthetic or to relieve pain following a major procedure. Modern use of cryoablation can be traced to the early 1960s, in which a device akin to the cryoprobe was first developed.
In its current iteration, cryoablation was originally indicated to alleviate terminal cancer patients of pain. Only recently has it been adopted for wider use and in otherwise healthy patients. Today, clinical applications include migraine headache, sinusitis and other craniofacial neuralgia, chest pain, abdominal and pelvic pain, back and lower extremity pain, chronic knee pain, arthritis, and peripheral neuropathy (often caused by distal nerve entrapments associated with diabetes and autoimmune disorders).
Cryoablation requires access to special equipment and a specific skill set which most healthcare facilities lack. Hudson Medical offers a comprehensive approach to pain management supported by highly specialized staff and the most advanced treatment modalities available, inspiring confidence and renewed hope for pain-free living.
Only facilities with specialized services have the expertise to perform cryoablation. To find out more, schedule a consultation with one of our Pain Management and Restorative Medicine specialists at Hudson Medical today!
References:
Bloudoff-Indelicato M. Freezing nerves may relieve chronic pain. Everyday Health [published online August 1, 2013]. https://www.everydayhealth.com/pain-management/freezing-nerves-may-relieve-chronic-pain.asp
Trescot AM. Cryoanalgesia in interventional pain management. Pain Physician. 2003;6:345-360. https://www.painphysicianjournal.com/current/pdf?article=MTk1&journal=16