Peripheral Field Stimulator

What is a Peripheral Field Stimulator?

A peripheral field stimulator is a medical device used in interventional pain management.

It consists of a small, implantable pulse generator that delivers controlled electrical impulses to small nerve fibres located beneath the skin in the area of pain. 

This stimulation helps block pain signals before they reach the brain, offering relief to individuals suffering from various chronic pain conditions. 

The device is implanted under the skin, similar to a pacemaker, and is designed to integrate seamlessly into daily life without interfering with normal activities.

Peripheral field stimulation may be recommended by your doctor as a treatment option for conditions such as low back pain, thoracic back pain, neuropathic pain and chronic headaches.

How Does Peripheral Field Stimulation Alleviate Chronic Pain?

Peripheral field stimulation alleviates chronic pain by interrupting the transmission of pain signals from the peripheral nerves to the brain. 

Here’s how it works:

• Implantation. A small pulse generator is implanted under the skin with electrodes,, typically in the area where the pain is localised. This generator delivers electrical impulses.
• Targeting Small Nerve Fibres. The electrical impulses specifically target small nerve fibres located beneath the skin in the region of pain. These small fibres are responsible for transmitting pain signals.
• Blocking Pain Signals. The electrical impulses interfere with the pain signals travelling along the small nerve fibres. By doing so, they effectively block or reduce the transmission of these signals to the brain.
• Gate Control Theory. Peripheral field stimulation operates on the principle of the gate control theory of pain. According to this theory, when non-painful sensations (such as the electrical impulses from the stimulator) reach the spinal cord before pain signals, they can “close the gate” and prevent the pain signals from reaching the brain, thereby reducing the perception of pain.
• Reduction of Pain Perception. By blocking or reducing the transmission of pain signals, peripheral field stimulation can lead to a decrease in the perception of pain experienced by the individual.
• Alternative to Pain Medications. Peripheral field stimulation offers an alternative to traditional pain medications, potentially reducing the need for oral pain medications and their associated side effects.

Overall, peripheral field stimulation provides a targeted and minimally invasive approach to managing chronic pain, offering relief and improving quality of life for individuals suffering from various pain conditions.

Generally speaking, a peripheral field stimulation device can offer reduction in pain by up to 50% (sometimes higher) depending on the underlying pathology and response of the patient.

It does not offer complete pain relief and does not work in every individual.

Hence a trial is initially undertaken to assess its effectiveness before committing to the permanent implant.

Why Would You Get a Peripheral Field Stimulator for Chronic Pain?

You might consider getting a peripheral field stimulator for relief from chronic pain for the following reasons:

• Inadequate Relief from Medications. If you’ve tried various medications for chronic pain, such as opioids, NSAIDs, or neuropathic agents, and haven’t experienced sufficient relief or have experienced intolerable side effects, a peripheral field stimulator could offer an alternative treatment approach.
• Non-Drug Treatment Option. Some individuals prefer non-drug treatment options for chronic pain due to concerns about medication side effects, drug interactions, or the risk of addiction. Peripheral field stimulation provides a non-drug approach to pain management.
• Avoidance of Surgery. Peripheral field stimulation is a minimally invasive procedure compared to surgical interventions for chronic pain conditions. If you prefer to avoid surgery or if surgery is not a suitable option for you, a Peripheral Field Stimulator could be a viable alternative.
• Targeted Pain Relief. Peripheral field stimulation targets the specific nerves responsible for transmitting pain signals in the affected area. This targeted approach can provide localised pain relief without affecting the entire body, unlike systemic medications.
• Reversible Therapy. Unlike surgery, a peripheral field stimulator device is completely reversible and can be removed completely at any stage. 
• Improved Quality of Life. Chronic pain can significantly impact daily activities, work, relationships, and overall quality of life. By effectively managing pain, peripheral field stimulation can help improve your ability to function, participate in activities, and enjoy life more fully.
• Treatment of Specific Conditions. Peripheral field stimulation has been shown to be effective in treating various chronic pain conditions, including neuropathic pain, chronic low back or thoracic back pain. If you have one of these conditions and have not found relief with other treatments, Peripheral Field Stimulation may be worth considering.

Ultimately, the decision to pursue peripheral field stimulation for chronic pain should be made in consultation with your doctor, who can assess your individual circumstances, medical history, and treatment goals to determine the most appropriate course of action for you.

The Risks of Peripheral Field Stimulation

While peripheral field stimulation is generally considered safe and effective for managing chronic pain, like any medical procedure, it carries certain risks and potential complications. 

Some of the risks associated with this treatment include:

• Infection. As with any surgical procedure involving implantation of a device, there is a risk of infection at the implant site. Proper sterile technique during the procedure and post-operative care can help minimise this risk.
• Device Malfunction. The implanted pulse generator or electrodes may malfunction over time, leading to inadequate pain relief or other issues. Regular follow-up appointments with your healthcare provider are important to monitor the function of the device and address any problems that arise.
• Lead Migration. The electrodes placed near the nerves may shift or migrate from their original position over time, potentially resulting in reduced effectiveness of pain relief. Proper placement of the electrodes and monitoring during follow-up appointments can help mitigate this risk.
• Pain at the Implant Site. Some patients may experience discomfort or pain at the site of the implantation, particularly in the initial days or weeks following the procedure. This usually resolves as the surgical site heals.
• Allergic Reaction. While rare, some individuals may experience an allergic reaction to the materials used in the device or surgical procedure. Your doctor will review your medical history and any known allergies to minimise this risk.
• Bleeding or Hematoma. There is a small risk of bleeding or formation of a hematoma (collection of blood) at the surgical site. Proper surgical technique and post-operative care can help reduce this risk.
• Nerve Damage. Although uncommon, there is a risk of nerve damage during the implantation procedure, which could lead to sensory changes or worsening of pain. Experienced healthcare providers and careful placement techniques help minimise this risk.
• Psychological Effects. Adjusting to life with a peripheral field stimulator can have psychological implications, including feelings of dependency on the device or frustration if pain relief expectations are not met.
• Failure. There are some rare situations when a patient will experience positive benefit from the trial but is unable to achieve a significant benefit from the permanent implant. In these instances, an attempt at programming is made for 6 months and if there is no success, the implant is removed. 

It’s essential to discuss the potential risks and benefits of peripheral field stimulation with your doctor before undergoing the procedure.

They can evaluate your individual circumstances, medical history, and treatment goals to help you make an informed decision about whether this treatment is the right option for managing your chronic pain.

The Process of Getting a Peripheral Field Stimulator

Peripheral field stimulation or getting a peripheral field stimulator device implanted typically involves two separate procedures performed on two different days or in separate appointments:

1. Initial Trial Electrodes:
   • This procedure is performed under sedation anaesthesia in a hospital setting.
   • Your skin is sterilised at the injection site, and a local anaesthetic is administered to numb the area.
   • Wires (leads) are inserted through a needle and placed under your skin in the target region by your pain management physician. X Ray guidance is used to accurately place the leads depending on the location.
   • These leads are connected externally to a smartphone-sized electrical pulse generator, which you carry with you during the initial test period to assess the treatment’s effectiveness.
   • You are generally required to stay overnight in hospital for monitoring with discharge and programming of the device commencing the next morning.
   • The device is programmed and trialled for a 7-14 days period as an outpatient. You are then reviewed in clinic where your doctor will remove the electrodes under sterile technique. This then concludes the trial. 
2. Permanent Neurostimulator Implant
   • This surgery is performed under general anaesthesia, with you lying on your stomach. You are required to stay in hospital for 1-2 days post procedure. 
   • Your skin is sterilised at the surgical site.
   • General anaesthesia is administered to ensure you are unconscious and pain-free during the procedure.
   • Your pain management physician implants the electrodes and the IPG battery under your skin for long-term pain management.

This pair of procedures allows for a comprehensive evaluation of the effectiveness of peripheral field stimulation before committing to a permanent implant. 

The initial trial period with external leads helps determine if the treatment provides sufficient pain relief, while the second procedure involves the implantation of a permanent device for ongoing management if the initial trial is successful.

Preparing for a Peripheral Field Stimulator

Before undergoing a peripheral field stimulation procedure at the Persistent Pain Solutions clinic, we’ll equip you with a pain chart and a pain diary to complete over a seven-day period. 

The pain chart helps pinpoint the areas of your body affected by pain, while the pain diary tracks pain levels and any observed changes each day.

Additionally, a brief survey will prompt you to describe the type of pain you experience in a few words.

For optimal preparation, please abstain from undergoing any other medical procedures, such as dental treatments or colonoscopies, within 48 hours before or after the procedure.

Prior to the procedure, refrain from eating or drinking for 6-8 hours (although medication can be taken with small sips of water).

You are required to stop smoking 6 weeks before the surgery. You will be provided with a full body antiseptic wash to be applied for a few days before the surgery to minimise the risk of infection.

Please inform us in advance if you have any allergies, a history of high blood pressure, bleeding or blood clotting issues (such as DVT or pulmonary emboli), a pacemaker or defibrillator, are taking antibiotics, or are feeling unwell.

Please inform the team if you are taking medications for diabetes, blood thinning medications or weight loss medications. You will be provided instructions on management of these medications by Dr Mittal before the surgery. 

Furthermore, arrange transportation to and from the appointment as you should not drive yourself due to the sedation involved.

After Getting a Peripheral Field Stimulator  (Follow-Up)

Following the procedure, you can expect to remain hospitalised for one or two days.

Complete recovery may take up to six weeks, during which incorporating gentle daily exercise like walking is recommended.

We’ll provide detailed instructions on the implantable pulse generator and specific activities to avoid. 

Post-procedure, anticipate some discomfort at the insertion site for approximately one week.

During this period, refrain from lifting heavy objects and avoid excessive stretching, twisting, or bending beyond 45 degrees.

Keep the incision dressing dry and undergo frequent checks for signs of infection.

You may commence driving 6 weeks after the procedure.

Dr Mittal will schedule a follow-up appointment for 10 days after your procedure for incision site review and stitch removal.

You can expect regular follow up reviews with Dr Mittal at 4 weeks and 6-8 weeks after the procedure.

During this time, the wound will be inspected for signs of infection or any other complication and programming of the device shall commence. 

Dr Mittal will regularly review you over the first 6 months to ensure the device is programmed effectively to provide pain relief, similar to the trial.

After that regular reviews are scheduled every 6 – 12 months depending on the need.

The IPG battery is changed every 5-10 years and usually requires a day case procedure under sedation in a hospital. 

Additional Issues to Consider With a Peripheral Field Stimulator Implant

• MRI compatibility. Peripheral field stimulators are generally MRI conditional. This means that most patients can obtain MRIs after the device is placed at a specific radiology clinic which has experience with such devices. You can contact your medical device representative or Dr Mittal for recommendation of a suitable radiology clinic that can perform the MRI. Rarely, the device needs to be removed to obtain specific forms of MRI images depending on the underlying pathology. (for eg, MRIs for brain aneurysms). 
• Recharging of the device. There are two types of batteries that may be used: Rechargeable or Non-rechargeable. The rechargeable batteries will require regular recharging either daily, every few days or weekly depending on the energy consumption. 
• Battery change. The IPG battery will require changing every 5-10 years depending on the energy consumption. This is usually a day case procedure performed under sedation anaesthesia.
• Driving. During the trial phase, you are not allowed to drive. After the permanent implantation, driving may be commenced only 6 weeks after the surgery. There are stimulation programs that may need to be turned off whilst driving (for eg: tonic stimulation). This is accommodated with other programs that can be used whilst driving instead.
• Travel. Dr Mittal does not recommend travel for the first 3-4 months after the procedure to allow for monitoring and programming of the device. When resuming travel, you will be provided with a ‘device card’ since the device will often ‘beep’ when moving through a metal detector at the airport.
• Exercise. During the trial period, you are restricted from certain movements such as raising arms above shoulder height, heavy lifting and forward bending. This is to avoid migration of the electrode leads. After the permanent implant, you are strongly recommended to follow the same restrictions for 3 months after the implant to allow for enough scar formation to prevent lead migration. During the first 3 months, you are allowed to walk on a regular basis for exercise. After three months, you may commence physiotherapy, hydrotherapy and weight training. 
• Swimming. You are recommended not to engage in swimming or utilise a public pool or spa during the trial period. This is to minimise the risk of infection. After the permanent implant, these restrictions continue for the first 3 months after the procedure. Following this, you may recommence swimming and hydrotherapy. 
• Activity. Once the device is working well and you are beyond the three month period, you may engage in any form of activity (such as running, jogging, walking, bike riding, weight training, swimming). However some activities are best avoided to prevent lead migration or fracture – these include high impact sports like playing footy, bungee jumping or scuba diving.

Getting a Peripheral Field Stimulator Removed

In the event that implanting a peripheral field stimulator fails to result in significant pain reduction, it can be swiftly removed via another procedure. 

However, if the anticipated relief isn’t achieved or the device proves ineffective, several other steps can be taken first:

1. Reevaluation. The initial step involves reassessing the placement and settings of the stimulator. Fine-tuning stimulation parameters or repositioning electrodes may enhance its efficacy.
2. Trial of Different Settings. Exploring alternative stimulation configurations can help identify settings that offer improved pain relief.
3. Revision Surgery. In certain cases, revision surgery may be necessary to reposition electrodes, replace malfunctioning components, or address underlying issues hindering effectiveness.
4. Alternative Treatments. If peripheral field stimulation falls short in pain management, alternative strategies such as different medications, physical therapy, cognitive-behavioural therapy, or other interventional procedures can be explored.
5. Exploring Other Modalities. If peripheral field stimulation proves ineffective, other neuromodulation techniques like spinal cord stimulation or dorsal root ganglion stimulation may be considered.
6. Managing Expectations. Open communication between you and your doctor regarding expectations and pain management goals is crucial. Adjusting expectations based on individual circumstances and treatment response is sometimes necessary.

Finding a Doctor Who Performs Peripheral Field Stimulation Near You

Locating a healthcare provider proficient in peripheral field stimulation in Melbourne or elsewhere across Australia is the right start for alleviating or managing many chronic pain conditions. 

Begin by consulting your general practitioner to secure a referral to a pain management specialist who provides peripheral stimulator treatments for chronic back or spinal pain.

Additionally, utilise online resources to research pain management clinics or seek recommendations from family, friends, or support groups—both virtual and in-person—who have navigated similar chronic pain challenges.

Peripheral Field Stimulation at Persistent Pain Solutions

The Persistent Pain Solutions clinic in Melbourne, Australia provides peripheral field stimulators and associated treatments to individuals dealing with chronic pain.

Designed for those seeking alternatives to surgical or invasive interventions, their services cater to patients who have exhausted other treatment options.

If your chronic pain condition proves resistant to conventional treatments, consider reaching out to the dedicated team at Persistent Pain Solutions.

Dr Mittal and her team will guide you through the process of determining whether a peripheral field stimulator could provide relief and they’ll collaborate with you to develop a personalised pain management strategy that lets you lead a more fulfilling life.