Ariana Smith: It's great to be back with you on UroToday. And this time we're going to talk about minimally invasive OAB procedures that you can offer in the clinic. So, these are the four guideline-concordant minimally invasive OAB options, chemodenervation with botulinum toxin injection, percutaneous tibial nerve stimulation, implantable tibial nerve stimulation, and sacral nerve stimulation with the office-based peripheral nerve evaluation or P and E. Botulinum toxin works by blocking acetylcholine release at the neuromuscular junction and at the level of the urothelium. And the early data provided strong evidence in both neurogenic bladder and idiopathic overactive bladder for improving maximum cystometric capacity, urgency incontinence episodes, and quality of life. When preparing patients for botulinum toxin injection, you need to ask them about urinary tract infection symptoms, history of recurrent UTI, and check a urinalysis.
In the setting of asymptomatic bacteriuria, it is recommended to treat with culture-directed antibiotics prior to injection, since the urothelium will be violated with the injection needle. It's important to counsel patients on the risks of incomplete emptying. And when pre-procedural PVRs are greater than 100 to 200 ccs, you should discuss the potential need for clean intermittent catheterization following the procedure. Implementation includes stocking botulinum toxin in the office as well as the necessary disposables for the procedure. You need a cystoscope and an injection needle. And there are several options, including integrated needles as shown here. And I've evolved from using intravesical 1% lidocaine to having the patient take a double dose of phenazopyridine. Patients know this as AZO. They take this one hour prior to the injection to provide local anesthetic on the inner lining of the bladder. This saves time in the clinic and also reduces instrumentation of the urethra. A single dose of prophylactic antibiotics can be used in patients at elevated risk of urinary tract infection or urosepsis.
But in the typical patient, I don't give antibiotic prophylaxis if their urine is clear on the day of injection. There are various injection techniques that have been described from just a few injection sites to up to 30 injection sites throughout the bladder, with dosages ranging from a hundred to 300 units. You should be billing both the injection and the medication if your clinic provided it. I do have my first-time injection patients come back for an office PVR with nursing at two weeks. Tibial nerve stimulation for the treatment of overactive bladder has been around for quite some time. Dr. Ed McGuire used Chinese acupuncture and found electrical stimulation of the posterior tibial nerve resulted in a decrease of bladder overactivity. Randomized controlled trials have demonstrated efficacy of PTNS compared to both sham and pharmacologic therapy. So, prior to PTNS in the office, you should ask about lower leg symptoms and be sure to inspect the lower leg for any signs of infection or ulcers or poor venous insufficiency.
The procedure can be done while a patient's on anticoagulation or aspirin as long as they don't experience severe bruising. PTNS is contraindicated with pacemakers and implantable defibrillators, as well as significant bleeding disorders, pregnancy, nerve damage to the tibial nerve, and severe neuropathy or vascular disease. PTNS can be performed by an RN, an advanced practice provider, or a physician. You do need to contact Laborie or Medtronic to procure a device and the disposables. Alcohol swabs are used to prep the skin and no antibiotics are recommended for this procedure. To do it, you place a 34 gauge needle, four to five centimeters above the medial malleolus at a 60 degree angle to the skin. And you place this at a depth of approximately two to four centimeters, depending on the thickness of the subcutaneous fat in that area of the patient's body. The stimulator then sends electrical impulses resulting in great toe flexion and a tingling sensation on the bottom of the foot. You can bill each session and maintenance sessions every four weeks. Missed appointments are a bit of a problem with using this treatment, and this has led to great interest in implantable tibial nerve stimulation.
There was a desire to move away from weekly office stimulation to more frequent personalized stimulation at home to optimize treatment response. And the biotech companies were also interested, which is why we now have three of these devices on the market. So, these are the three devices available, and all of them achieve moderate success with respect to reduction in urgency incontinence episodes and improvement in quality of life. There are not yet any head-to-head trials with these technologies. Prior to implantation, you do need to ask again about lower leg symptoms and about physical activity like soccer that may affect the device once it's implanted in the lower leg. You need to ensure you're at least five centimeters away from other implants in the body. The only absolute contraindications are severe neuropathy, severe vascular disease, and need for diathermy. Conditions that hinder wound healing should be considered carefully as this is a permanent device being implanted. You do need to counsel patients on the need for recharging the device.
It is MRI conditional, all three of them, MRI conditional for 1.5 and 3.0 Tesla full-body MRI. You may need a company rep to attend the procedure and program for you in the beginning. You do need to carefully prep the lower leg and drape the foot out of the field. And I would recommend prophylactic antibiotics at this time as we're continuing to evolve data in this space. I also recommend a compression stocking for approximately 72 hours after implantation. The billing code currently is a category three. You can crosswalk that to another neuromodulation code. I tend to use 64590. This is a category one code that allows you about 5.1 RVUs. There is no global, so you can bring the patient back in three to four weeks for a programming visit. Finally, SNS. SNS was described in 1990 and approved for use in 1998. It's believed to work by inhibiting sensory input from the bladder to the spinal cord and reducing involuntary detrusor contractions. The early randomized controlled trials demonstrated efficacy and durability in reducing OAB symptoms.
The peripheral nerve evaluation is performed through the S3 foramen using the basic evaluation lead and the ENS or the external neurostimulator shown in white. And it's critical you do look at the skin in this area of the body prior to implantation to make sure there are no infections or decubitus ulcers in this area that would preclude implantation of the device if there was a successful trial. Implementing this in the office is generally done with the rep from the company who brings the device. Antibiotics are not recommended since this is a temporary lead which will be removed prior to full implantation. You mark the patient nine centimeters from the tip of the coccyx and two centimeters from the midline bilaterally and needle placement is approximately two centimeters above this crosshair. You can use a 50 modifier for bilateral lead placement, and you can bill for initial programming at the time of the needle placement. So, P and E is a great option for those who have the personnel and can streamline the process in the office. I'm going to go ahead and stop sharing, Alan, and we can talk about these therapies.
Alan Wein: First question is, how do you decide with a given patient whether to do them in the clinic or somewhere else in a formally allocated space for that?
Ariana Smith: Yeah. So, a lot of patients request treatment in the office. They do this because they want to save time. Some of them who have out-of-pocket costs want to save money. I would say most of the time it's to save time. And once we explain the level of discomfort to expect, most patients are agreeable in fact to doing it in the office. There are some who do request anesthesia. They want to have sedation. And of course, that's not something we offer in our clinic setting, so we'll bring them either to an ambulatory care center or the hospital, depending on their risks for anesthesia.
Alan Wein: I mean, generally speaking, is there any difference in out-of-pocket money for the patient? In other words, do they have to lay out more money for the clinic as opposed to the OR, as opposed to the ambulatory surgery center?
Ariana Smith: For most patients, there is not a big difference of their out-of-pocket costs, but there are some insurances that have high-deductible plans, in which case this would be important to understand ahead of time, and knowing where they are in their deductible, how far along they've come, and sometimes that can vary across the year. For the average patient who has both medical and prescriptive coverage, these procedures are covered. Some require prior authorizations while others do not, but this is something we do offer in the clinic so the patient can understand ahead of time whether it is covered by their insurance or not.
Alan Wein: What type of help do you need to do these in the clinic? In other words, how many other people, if any, are required to do this with you?
Ariana Smith: Yeah, that's obviously a great concern as we're all being pulled in multiple directions. So, we want to keep all our staff working at the top of their scope. They just need MA assistant. So, that's a medical assistant. For example, when I'm doing a botulinum toxin injection, the medical assistant gets the patient from the waiting room, takes their vital signs, brings them into the room, gets them set up. I come in, I do obtain informed consent myself, and I do prep, inject local anesthetic and place the cystoscope myself. Once the cystoscope's in place, it just takes a few minutes to do the injection, and then the patient will sit up from the table and the MA takes it from there, gets the patient to the restroom to empty their bladder, dressed, and out to the front desk. So, we can do all of that in the span on a good day, that's about 10 minutes, if they're not waiting for me to come in the room.
Alan Wein: The implantables, there are two that are implanted above the fascia and one that's implanted below the fascia. Does it make any difference, or would it make any difference as to the setting chosen for above the fascia or below the fascia? In other words, as far as the actual difficulty of the implantation, what you might expect, what the patient might expect, is one type more suitable for the clinic than the others or not?
Ariana Smith: Yeah, I think that's a great question. And I think probably most likely this is not going to be relevant once everyone is trained in both techniques. At this point, I've only done above the fascia. I've not done below the fascia. I've only done the trainings online. And from what I can tell, it's a slightly technical difference. The placement above the fascia is quite simple. I think once you've developed the plane of the fascia, the placement underneath may take just a little more pressure to develop the space, and that's an area that you would carefully localize with anesthesia with local anesthesia before you placed your instruments to dissect that space. But I think ultimately, once we're all well-trained, this isn't going to be a big difference as to whether we can do it in the clinic or in the operating room.
Alan Wein: Well, as usual, a great education, a terrific talk, and hopefully we answered most of the questions that somebody would ask about this if they're not familiar with the subject. So, listen, thanks once again for being on UroToday and look forward to having you back again for another topic.
Ariana Smith: Great. Thank you, Alan.