In March 2021, the article “Microvascular Transposition Without Teflon: A Single Institution’s 17-Year Experience Treating Trigeminal Neuralgia” was published in the peer-reviewed journal Operative Neurosurgery. The senior author and surgeon of the article is FPA Medical Advisory Board member, Dr. Richard Zimmerman, at Mayo Clinic in Arizona. The content below, provided by Dr. Zimmerman, shares some background behind the article, as well as a brief synopsis of the findings. Although copyright law prevents FPA from providing copies of the paper, for those interested in reading the complete article as published, the citation is: Operative Neurosurgery 2021 Mar 15;20(4):397-405.
Microvascular decompression (MVD) as a treatment for trigeminal neuralgia (TN) has been foremost championed by Dr. Peter Jannetta. Through his tireless support and work to help the facial pain community, Dr. Jannetta also made this procedure a part of mainstream neurosurgery. Furthermore, it should be recognized that Dr. Jannetta’s work helped educate the medical community outside of neurosurgery about the most common cause of this disorder. In his seminal work published in the New England Journal of Medicine in 1996, Dr. Jannetta was able to show that moving a blood vessel off the trigeminal nerve provided lasting relief from the terrible condition we know as trigeminal neuralgia (TN). The impact this neurosurgeon made on patients, neurosurgeons, and all physicians has been so great that MVD surgery commonly bears his name – the Jannetta Procedure.
In the initial descriptions of this procedure, the technique used to elevate a blood vessel off the trigeminal nerve was to insert a small piece of sterile Teflon felt under or against the vessel such that the compression was eliminated. The use of Teflon felt has been very effective, demonstrated by the successful results that Dr. Jannetta and many neurosurgeons have achieved. Yet as my career treating patients with TN progressed, I began seeing patients who previously had an MVD but either still had pain or experienced only a short period of relief before their TN reappeared. After seeing several of these patients, I had to consider that perhaps something about the way their initial procedure was done didn’t truly accomplish the goal Dr. Jannetta championed. Furthermore, as MR imaging quality became more sophisticated and detailed, it became apparent that the re-imaging of these patients showed a mass of Teflon against the trigeminal nerve at the root entry zone. Could it be that in these cases, the surgery only replaced vascular compression with Teflon compression, or that the Teflon against the nerve still transmitted vascular pulsations? Finally, with fellowship training as a microvascular surgeon, I was quite familiar with options available to mobilize the blood vessels of the brain, even to the point of relocating their position. Ultimately, I decided that in my surgical cases for TN, I would try to avoid using Teflon and instead simply relocate or transpose the position of the compressing blood vessel(s) away from the trigeminal nerve. To maintain the vessel in its transposed location, I used a biologic adhesive known as “fibrin glue” that is commonly used in neurosurgery. The goal of this technique was to completely remove anything whatsoever from touching the “sensitive” trigeminal nerve. Thus, I started performing “microvascular transpositions” (MVT), otherwise known as a “Teflon-free MVD.”
This concept was not invented by me, and several other neurosurgeons have written about their series of trigeminal neuralgia surgeries employing a “non-compressive” technique. Variations to the use of Teflon have been described, including the use of sponges, glue, sutures, slings, and even aneurysm clips. Furthermore, this is not to say that there is anything wrong with the use of Teflon. However, the pattern that I observed in post-surgical recurrences of pain typically involved Teflon seen against the trigeminal nerve on imaging. I cannot recall seeing a failed case of MVD surgery where Teflon was used, but where it was inserted away from the nerve – truly achieving a compression-free result. However, I was concerned that the teaching of MVD surgery was becoming simplified to the point of “stuffing Teflon between the nerve and vessel,” without necessarily achieving a good or complete decompression. This might be even more so for surgeons who do not see many trigeminal neuralgia patients or do MVDs infrequently.
After almost 20 years of using this technique consistently, I wanted to evaluate and compare the long-term results of this strategy to treat TN. Thus began the effort to reach out to my patients who had a “Teflon-free MVD” using the method of patient reported outcomes. Patients who had an MVT TN procedure were sent a questionnaire about their surgical outcome. While far from reaching all the patients who had this type of surgery, there were 102 patients who had contact information available, and we received 85 responses. The ages of these patients who responded ranged from 20-89 years, and the duration of time after surgery ranged from nine months to more than 17 years. Long- term, pain- free results were achieved in 89.4% of patients with a mean follow-up duration of 6.9 years. This is a very high rate of success and compares with the best reported outcomes in the literature. We were also able to examine the outcomes divided into the patients who provided a description of intermittent attacks of facial pain alone (TN type 1) vs. attacks of facial pain with a background component of constant pain (TN type 2). While both groups did well, we did find that TN type 1 patients did better, with nearly 92.8% being pain-free at 10 years. This study certainly has limits, and they are outlined in the full article. The conclusion, however, is that Teflon is not necessary for a successful TN surgery. Achieving a good decompression whether or not Teflon is used – potentially with no residual contact against the trigeminal nerve – arguably should be the goal of MVD surgery.
Patients should always feel comfortable discussing any plans for an operation with their surgeon, including the option of having a “Teflon-free MVD.” However, given the widespread and classic teaching of using Teflon, it is not likely many neurosurgeons will be experienced treating trigeminal neuralgia with vascular transposition. One therefore needs to decide if they want to ask their surgeon to perform a procedure with a technique they don’t routinely do vs. finding a surgeon who is familiar with this technical nuance.
