What is InterStim Therapy?

The Medtronic InterStim System for Urinary Control is indicated for the treatment of urinary urge incontinence, urinary retention, and significant symptoms of urgency-frequency in patients who have failed or could not tolerate more conservative treatments. This therapy uses mild electrical pulses to stimulate a nerve near the tailbone in your lower back. This nerve called the sacral nerve, controls your bladder and the muscles that manage urinary function. For certain patients, stimulating the nerve relieves the symptoms of urge incontinence and significant symptoms of urgency-frequency and urinary retention.

What do nerves have to do with urination?

Nerves carry information to and from the brain. The sacral nerves control the bladder and muscles that relate to urination. When the communication system between the sacral nerves and the brain is not working correctly, a person may have bladder control problems.

Is this a proven therapy?

InterStim therapy has been used successfully with over 1,500 patients over many years. It was approved in Europe in 1994 and by the U.S. FDA (Food and Drug Administration) in 1997 for urge incontinence. It has since been approved (April 1999) to also treat urinary retention and significant symptoms of urgency-frequency.

Will the InterStim System cure my bladder control problems?

This therapy is not a cure, but may be an effective treatment for your symptoms. How well it relieves symptoms varies from person to person. And when you turn the stimulation off for any length of time, your symptoms will return.

Does Insurance pay for it?

Many insurance companies pay for the InterStim Therapy. Dr. Schoenfeld will communicate with your insurance company to request coverage. He will explain your symptoms and InterStim Therapy. You will also need to communicate with your insurance company.

What are the Benefits of InterStim Therapy?

InterStim Therapy can eliminate or greatly reduce urinary symptoms for many people suffering from urge incontinence, significant symptoms of urgency-frequency, or retention who have show a good response during test stimulation. It is completely reversible and can be turned off at any time.

Have Studies been done on InterStim Therapy?

Medtronic conducted a worldwide clinical trial of people who and urinary urge incontinence, urgency-frequency, and urinary retention. Clinical trials are controlled studies that analyze how well a therapy treats a condition and how safe it is. The study results helps government agencies (such as the FDA) decide whether to approve a device or therapy for commercial use.

What were the results?

The results show that the therapy successfully treated certain bladder control problems in patients for whom other treatments did not work. Here are the results 12 months after surgery:

Urge Incontinence (12 month results for 38 implanted patients):

45% of patients remained completely dry
34% of patients had >= 50% reduction in number of wetting episodes.
79% clinical success

70% of patients eliminated heavy leaking episodes at baseline. 30 of the 38 patients with 12 month data experienced heavy leaking episodes.

Urgency-Frequency (12 month results for 33 implanted patients):

33% of patients reduced the number of voids by 50% or more
31% of patients reduced the number of voids to normal (4-7 per day) in patients who were originally voiding more than 7 times per day.
64% clinical success

82% of patients improved degree of urgency before a void. (Because urgency-frequency patients feel a strong urge to void, and void small amounts of urine each time, "success" means that patients increased the amount of urine voided each time and felt either the same or less urgency with each void.)

Retention (12 month results for 38 implanted patients):

61% of patients eliminated the use of catheters.
16% of patients had >=50% reduction in the amount of urine emptied from the bladder using a catheter.

With a reduction in symptoms, patients can return to activities that are part of normal living such as going for walks, attending functions, sleeping through the night, and dining out.

What problems did patients experience in this study?

In the Medtronic study, 219 patients were implanted with the system. Fifty-two percent, or 113 patients, reported 201 problems with therapy. Problems ranged from minor concerns such as skin irritation to major concerns such as pain, infection, or device problems. Eight percent (or 16 problems) resolved on their own; 38% (or 77 problems) required some medical treatment, but not surgery or hospitalization; and 54% (or 108 problems) required hospitalization or surgery to correct. None of these problems resulted in permanent injury to patients. At the time the database was closed and results were measured, 9% of them problems were not solved or corrected. Following the study, physicians continued to work with their patients to resolve the remaining problems.

Below is a list of problems that happened during the study. The percentage indicates how likely it is that each event might happen. For example, a 15.3% probability means there is a 1 in 7 chance that within the first year someone who has a system implanted could feel pain where the neurostimulator is.

• Pain where the neurostimulator is placed (15.3%)
• New pain (9%)
• Lead migration (8.4%)
• Infection (6.1%)
• Transient (quick/brief) electric shock (5.5%)
• Pain at lead site (5.4%)
• Adverse change in bowel function (3%)
• Other (combined total of 16%)
  (The following problems each occurred less than 2% of the time: technical problem, suspected device problem, change in menstrual cycle, adverse change in voiding function, persistent skin irritation, suspected nerve injury, and device rejection. The following problems each occurred less that 0.5% of the time: change in sensation of stimulation, grand mal seizure, hematoma or eroma, urinary hesitancy, neurostimulator turns on or off, lack of orgasm, lack of efficacy, numbness and tingling, foot/leg movement, strong anal sensation, unable to perceive simulation, stress urinary incontinence, swollen feeling in abdomen, vaginal cramps, superficial connection, and possible skin perforation at neurostimulator.
  

Problems may be resolved with surgery, medical therapy such as drugs, or reprogramming. These events may also resolve over time, or remain unresolved. Thirty-three percent (one out of three) of the patients implanted had additional surgery to resolve a problem.

A potential problem that may occur, but was not reported in the clinical study is permanent undesirable sensations. Although no patient experienced this, it could possibly occur.

Generally, no. But you should talk to your doctor about performing any strenuous activities such as heavy lifting or vigorous exercise, especially right after surgery.

As with any surgery, limit your activities at first. "Take it easy" during the first 3 to 6 weeks to let your body heal. Avoid bending , twisting, stretching, or lifting heavy objects in these weeks after surgery to help ensure a good result.

 

What is an InterStim System?

The InterStim System consists of components that are implanted into your body, plus hand-held devices that let you and your doctor control the internal system after it has been implanted.

The components that are implanted are:

1. A neurostimulator (much like a pacemaker) that sends mild electrical pulses through the lead.
2. A lead, or this wire, that carries the pulses to stimulate a selected sacral nerve in the lower back. The lead is attached to an extension (another thin wire) that connects the lead to the neurostimulator.

Three other devices are used by you and your doctor to control and adjust the internal system:

1. The patient programmer is a hand-held device that lets you adjust the strength of the stimulation and allows you to turn the device ON and OFF.
2. The control magnet simply turns your system ON and OFF.
3. The physician programmer lets your doctor adjust all of your neurostimulator's settings.

Before you leave the hospital, your doctor will decide if you should have a control magnet, patient programmer, or both. If you do not have either device, contact your doctor

What size is the neurostimulator?

The Medtronic neurostimulator is about the size of a stopwatch.

Will people be able to see that I have the system?

The neurostimulator and lead are placed under the skin. If you are quite thin, the neurostimulator may appear as a small bulge. This will not be visible under clothing.

What will happen during the surgery?

First of all, before the surgery, your doctor will talk to you abou the procedure. Together you will decide where to place the neurostimulator based on your medical history, the kind of work you do, and your own body structure. Prior to surgery, your doctor may mark the skin with a surgical marker to indicate where the neurostimulator will be placed. When deciding where to mark the area, you may be asked to bend, twist, sit, or stand. This will help the doctor decide the best site for the neurostimulator.

NOTE: Pacemakers can be affected by an InterStim System if the two systems are too close to each other. Tell your Dr. Schoenfeld if you have a pacemaker so he can assess any possible electrical interference problems and decide if you can also have an InterStim System.

The surgery typically takes 2 to 3 hours. There are 2 or 3 incisions. The following describes a typical surgery. Your doctor may modify the number of incisions and the location of your neurostimulator based on what he or she determines will work best for you.

• This surgery is typically performed under general anesthesia, and consequently you will not see, hear, or feel anything during the operation. To place the lead, the doctor makes an incision over your sacrum (a triangular bone in your lower back) and positions the lead near your sacral nerve.

• The doctor then makes a small "tunnel" beneath your skin to pass the lead from your lower back to an incision on your side.
  
  
• The doctor next makes an incision in your lower abdomen and creates a "pocket" in the fatty layer of tissue. The neurostimulator site to the incision at your side to connect the wire coming from the neurostimulator to the one coming from your back. All parts of the system will then lie beneath your skin.
  
  
• Your incisions are stitched closed and covered with a dressing.

What happens after surgery?

Patients are usually out of the hospital the next day. Your incisions will probably feel sore, perhaps even painful for the first two weeks. This is especially true of the incision in your lower back. This is normal and should get better as you heal. To be more comfortable, you may want to have a pillow at your lower back when you wit. Your doctor can provide medication to treat the pain. If the pain is not improving after the first two weeks, or if you notice any swelling or redness at your incisions, please contact your doctor.

Within a week of the surgery you will go to your doctor's office where he or she will use the physician programmer to set the stimulation values. To help identify the best settings, your doctor will ask you questions about what you feel as he or she programs the neurostimulator. You should feel a slight tingling, not jolting - more stimulation is not necessarily better. It should feel much like your test stimulation.

Gradually increase your activity levels as your incisions heal. On your doctor's advice and as you feel better, you should be able to resume an active lifestyle. You should be able to shower or bathe as before and enjoy normal activities (such as travel, have sex, , go to work, walk, hike, work in the garden, and so on). You will have to make some adjustments in your activities, such as turning off the neurostimulator when you operate a vehicle, or being more aware of the theft-prevention devices in stores. These adjustments are described in the precautions section.

Once normal activity is resumed, some patients find that the neurostimulator is not placed in the most comfortable position. Your doctor can usually reposition the neurostimulator without requiring an overnight hospital stay.

In some cases, patients may need surgery to reposition or replace the lead, the wire that carries stimulation tot he nerve. This may require an overnight stay in the hospital.

Keep your appointments

You and Dr. Schoenfeld will adjust the stimulation settings to maintain the most effective control of our symptoms without discomfort. You may need to make several visits to fine-tune the settings that are best for you. These office visits generally take just a few minutes to reset parameters. You will not have to undress or change clothes.

Your doctor will probably set up a schedule of regular visits. A typical schedule calls for visits one week, one month, three months, six months after surgery, and as needed after that. Be sure to keep these follow-up appointments since they help you and your doctor assess the therapy and make adjustments to improve it. Tell your doctor if your address changes. And if you change doctors, be sure to have your medical history sent to the new doctor.

Carry your InterStim identification card

You will get a temporary identification card after your surgery. A few weeks later, Medtronic will send you a permanent ID card that has information about your system and identifies your doctor. It is a good idea to carry your system ID card with you at all times. Some patients may also wish to wear a medical alert bracelet.

Above all, follow your doctor's advice. He or she will help you decide if you need medications along with your InterStim System to treat your bladder problems. It can be helpful to tell your family and others important to you what your doctor and nurses have said and even to bring them along when you talk with your doctor.

As the incisions heal, you should become more comfortable. You may feel a slight tingling sensation that tells you the system is on and working.

How often do I have to go to a physician for check-ups?

Once the system settings have been fine-tuned (usually within the first six months) you may only need check-ups once or twice a year. Depending upon your situation and your doctor's requirements, you may need to go more or less often than that.

Will I need further surgery after my InterStim System has been implanted?

The use of the physician and patient programmers allows you and your physician to make adjustments to the stimulation, so that you get the best control of your symptoms with the leaset discomfort. Generally, there should be no need for further surgery until your neurostimulator case, the battery cannot be replaced separately. Therefore, when it is time to replace the battery, your doctor will remove the entire neurostimulator and replace it with a new one. During replacement surgery, your doctor will also check your implaned lead (and extension). If those are working properly, your doctor will connect them to the new neurostimulator. If they are not working properly, your doctor may also need to replace them.

What will happen when the neurostimulator battery runs down?

Soon after you have your system, your doctor can estimate how long the battery in your neurostimulator is likely to last. Some people need more stimulation, which drains the battery faster. Eventually, as with all batteries, your neurostimulator battery will run down.

As the battery runs down, the stimulation output may fluctuate. As a result the system may be less effective in controlling your symptoms. This is normal and no cause for concern. If you are uncomfortable with the level of stimulation, it may help to change the stimulation amplitude.

In any case, when you experience less control of your symptoms, tell Dr. Schoenfeld. Make an appointment to discuss what happens when the battery is changed. Replacing the battery is usually an outpatient procedure. your doctor makes a small incision near your neurostimulator, removes the old device and replaces it with a new one.

How long does the neurostimulator battery last?

Battery life depends on the individual settings your physician has programmed for you. Your doctor can determine the expected battery life after your first programming.

Can I check the status of the battery?

Yes. Use the patient programmer to check the status of the battery

Can the battery be recharged?

No. Because the battery is sealed inside the case the entire neurostimulator must be replaced.

How can I control the level of stimulation from my InterStim System?

There are two hand-held devices you can use to control your InterStim System, the patient programmer and the control magnet. Both can turn the neurostimulator OFF and ON. The patient programmre can also adjust the stimulation levels. Some patients use the patient programmer. Others use only the magnet.

How do I use the patient programmer?

The patient programmer is a hand-held battery operated device that sends signals to your neurostimulator. Place the programmer over the neurostimulator pocket and press the appropriate buttons to turn your neurostimulator ON and OFF, or to change the amplitude (stimulation strength) within the safe settings your doctor programmed. (More detailed information can be found in the Patient Manual packaged with the InterStim patient programmer.)

How do I use the control magnet?

The control magnet lets you turn the neurostimulator ON and OFF (you cannot use your control magnet to adjust amplitude). Hold the curved part of the magnet in the palm of your hand so that the flat end is toward your body. Hold the control magnet against your clothing or skin directly, over the sneurostimulator for 1 or 2 seconds, and then remove it. If your neurostimulatior is ON, this will turn it OFF. If your neurostimulator is OFF, This will turn it ON.

If the control magnet does not turn your neurostimulator ON or OFF, try changing the angle at which you hold the magnet against the enrurostimulaor pocket. For example, try a "1 o'clock" or 4 o'clock" position.

Do not drop your control magnet because it can break. In an emergency you can use any large magnet (such as a horseshoe magent) to turn the neurostimulator ON and OFF. If you break or lose your control magnet, contact Dr. Schoenfel or Medtronic as soon as possible. IF you have a patient programmer, use it until you have a new control magnet.

Be careful with your control magnet!

Your control magnet is just that, a large magnet, and it can damage a number of common items. It is best to always keep your control magnet several inches away from the following:

• Watches or clocks

• The magnetic strip on the back of bank cards, credit cards or other plastic cards. (Don't put your credit cards and magnet together!)

• Video tapes, audio tapes or computer disks.

• Home electronic items like a computer, television, VCR, or camera.

If you carry the magnet in a purse or waist pouch, keep it on the side away from the neurostimulator so that it does not accidentally turn your neurostimulator ON or OFF.

What do I need to know about the effects of stimulation?

Is it normal to feel stimulation increase or decrease when I change positions?

Most of the time you will not feel changes in your stimulation. But quick movements or changes in posture could make it feel like the stimulation is increasing or decreasing. Occasionally, when they change position, patients feel the stimulation as "shocking" or "jolting."

The lead of your system is attached near a sacral nerve in your lower back. When you move your body the lead may be slightly closer to the nerve. If this happens to you it may feel like the stimulation has increased or decreased. Or it may feel like the neurostimulator is turning ON and OFF. This is normal. You are still receiving the level of stimulation you need to control your symptoms. If the stimulation becomes uncomfortable when you change body positions, or your symptoms return, call your doctor.

What does it mean if I don't feel the stimulation all the time?

Your doctor may have programmed your neurostimulator to "cycle," that is, it will turn ON and OFF at regular intervals. As long as th system is controlling your symptoms, do not worry if you cannot feel it.

What do I do if the stimulation changes or becomes uncomfortable?

First, decrease the amplitude by using your patient programmer. IF that does not solve the problem, turn your neurostimulator off, and contact your doctor.

Will the stimulation keep me awake at night?

No, it should not. If it does, contact your doctor.

What precautions do I need to know about?

Because the system can be affected by many items in and around the home, as well as other places that are part of your everyday life, you will need to become more aware of your surroundings. You will also have to do some planning ahead of time for some other types of medical procedures. The Warnings and Precautions that follow provide you wil information on when you shouldn't use the system and what things could affect your system.

WARNINGS
Vehicle and Power Equipment

Sometimes when you change your body position you may feel a sudden increase in stimulation - even a jolt or shock. This is not harmful, but it may surprise you. That is why you should not drive a car or use power tools when your system is ON. The change in stimulation could cause you to lose control of your motor vehicle or any equipment you are using. To prevent this, decrease the amplitude to zero and turn your neurostimulator OFF before you drive any vehicle or handle equipment such as power tools. (To decrease the amplitude press the DOWN arrow on the patient programmer). If the amplitude is not set at zero and the system is turned on accidentally by a magnet, you could feel a slight shock.

**This therapy is not intended for you if you have a mechanical obstruction such as benign prostatic hypertrophy, cancer, or urethral stricture.**

PRECAUTIONS
Medical Procedures and Equipment

Always let medical and dental staff know that you have an Interstim device before you undergo tests or treatments. Tell your doctor if you have a pacemaker. The InterStim Therapy could affect the oepration of the pacemaker. Also tell your dentist where your neurostimulator is implanted. With proper precautions, most medical procedures will not inerfere with your system.

The following equipment and treatments may affect the operation of your neurostimulator system. Therefore they are NOT recommended.

• Ultrasound, scanning equipment.

• Treatments such as diathermy (for muscle relaxation), lithotripsy (e.g. for kidney stones) and electrocautery (used during surgery).

• Radiation therapy over the neurostimulator
  

• MRI (magnetic resonance imaging) over any part of the InterStim System.
  
  
• Heart defibrillators.

Most routine diagnostic procedures such as flouroscopy and x-rays are not expected to affect the InterStim System operation. However, equipment used with these machines (such as transmitting antennas) could interfere.

If you think an electrical device or magnet is interfering with your neurostimulator, move away from it, or turn the device off. Then use your patient programer or control magnet to return your neurostimulator to the desired ON or OFF setting.

If there is still a problem, your doctor can use the physician programmer to disable the magnet ON/OFF option. If the magnet option is disabled, you must use the patient programmer to control your neurostimulator because the magnet will not turn the neurostimulator ON or OFF. Be aware that even if your neurostimulator is turned OFF, strong electrical deviced or magnets can still affect the lead. This could result in a sudden brief shock or jolt.

Theft Detectors and Screening Devices

Use care when approaching any walk-through security devices. These include theft detectors found in public libraries, grocery or department stores, or airport screening systems. These devices can cause the neurostimulator to turn ON or OFF. It is also possible that you could feel a brief burst of stimulation (a jolt or shock) as you approach a device. To avoid possible problems you may want to show your InterStim identification card and ask those in charge to let you bypass the device.

Home Appliances

Most home appliances do not affect the way your neurostimulator operates. A few devices with permanent magnets (e.g. large stereo speakers, refreigerator doors, and telephones) could turn your neurostimulator ON or OFF if your neurostimulator comes in very close contact with them.

Control Magnet

Your patient magnet should be kept away from computer disks, credit cards and other items that are sensitive to magnetic fields.

Commercial Equipment

Commercial electrical equipment (for example arc welders, induction furnaces) as well as high voltage power lines may interfere with your neurostimulator system if approached too closely.

Other common questions...

Will the implanted system feel different from the test system?

The stimulation you feel and the relief of symptoms should be very similar.

Should I have the neurostimulator on or off when I go to the bathroom?

Ask Dr. Schoenfeld for specific instructions.

Can stimulation be used during pregnancy?

The safety of this therapy for use during pregnancy has not been established. If you learn, or suspect that you are pregnant, turn off your neurostimulator and call your doctor.