Steven L. Giannotta, MD, a neurosurgeon at Keck Medicine of USC, discusses symptoms, treatments and surgical options for trigeminal neuralgia and hemifacial spasms.
Hello. I'm Steve Janata on the department chairman of the neurological surgery um, apartment at Kick USC Medical Center. And I'm director of the neurosurgical training program at L. A C. USC Medical Center. Today I selected to topics, uh, to somewhat unusual neurological syndromes. The reason I selected Botham is they have a similar, uh, surgical strategy for their management. The first syndrome is called trigeminal neuralgia. It is a painful condition. Those of you who may be watching this and may have had the syndrome or have the syndrome know exactly what I'm talking about. It's an almost on electric shock like phenomenon in the side of the face. From, ah, neurological standpoint. It involves three divisions any of three divisions of the trigeminal nerve division. One is the I and the forehead. Division two is the cheek, and Division three is the chin, and you can see from the slide. It's called a lance in ating pain, and it means that it comes and goes, and it comes usually without warning. Lasts seconds, two minutes. But those of you may have had this syndrome know that those minutes could seem like hours because of the severity of the pain. There are unusually triggers that can trigger the paint, UH, some of which are simply talking, uh, eating, brushing the teeth. And as a result of that, some people lose a lot of weight because they just don't want to eat. Figuring that that's the next thing that's going to trigger their pain, there are pain free intervals. Thankfully, faras causes. The main cause we're gonna talk about today is vascular compression. But we also know that tumors in and around the trigeminal nerve can cause it. Similarly, arteriovenous malformations can cause it, which are a lot less common. But those patients with multiple sclerosis can have symptoms of trigeminal neuralgia without either of those other three causes. And treating multiple sclerosis cause trigeminal neuralgia is a difficult deal. It's faras treatments are concerned. They come in two different categories. We'll talk about the destructive in a minute. But as far as the nondestructive, I've got Farmer there on this list. And that means that the initial treatment for diagnosed trigeminal neuralgia is medications. There are a number of medications that can be effective in managing this. They usually come out of the category of anticonvulsant medication, so those medications that are used for patients with seizures, the most common and actually the most effective, is carbamazepine. Unfortunately, not everybody can tolerate taking that medication. It's got a lot of side effects, and that's when patients end up coming to me. Either The pharmacological treatment doesn't seem toe work, or the complications or side effects of the medications are so severe that patients can't work on can't function because of issues with balance and memory. If we assume that most causes of trigeminal neuralgia, our vascular compression, uh, then the surgical management of that disorder is gonna be the most effective, and not only that, it's gonna be curative. If we look at the destructive categories over on the left, we see things like rise Artemis, radio frequency, avulsion, compression, glycerol, etcetera. These air, all a techniques that partially injured the trigeminal nerve have stood the test of time, Uh, sometimes cause, uh, numbness of the face, which is why we tend to steer patients to either the pharmacological management or microvascular decompression, which we'll talk about ast faras diagnosis. The diagnosis is made by just simply asking the patient to explain their pain. If they talk about a triggering herbal, electric shock like phenomenon on one side of the face. Most likely, that's trigeminal neuralgia. But Aziz, you can see from the arrows on this slide. Uh, we we can actually look for the blood vessel that contacts the trigeminal nerve on either M r I's M R A's or fusion M R I m r A. Studies and get an exact, um, idea of what might be causing the pain, especially if it's a blood vessel. Once we do that, there's a very simple technique, uh, relatively speaking. As far as North surgery is concerned, Thio separate that blood vessel that's touching the nerve, and it's called a microvascular decompression. It's an incision behind the ear with a small removal of bone. A two millimeter retractor is placed. We identify the nerve, and we look for the blood vessel that's touching the nerve. Once we see that we can move, that blood vessel doesn't have to move very far, and then we buttress that blood vessel away from the nerve, using something that's called Teflon felt. So in effect, we put a pillow between the artery on the nerve. Here's the incision. It's relatively small. It's behind in this case, the right here. The amount of bone we remove is no more than an inch in diameter. Uh, and here's a picture of the trigeminal nerve that white structure you see and those to red structures. You see, behind the nerve is the superior Sarah Beller artery, which classically gets behind the nerve, pulsates against the nerve with every heartbeat and causes the irritated effect. Uh, that causes the lance in ating pain. This arrow shows the Iraq noid, which is the covering of the brain for you surgeons, uh, that are watching this or you budding surgeons. Uh, it's important to be is minimally invasive with this technique is possible because one of the side effects is hearing loss. And that hearing loss actually comes from retracting the cerebellum to vigorously. By leaving this Iraq noid veil intact, you can get a new assurance that you're not pulling on the cerebellum or retracting the cerebellum, uh, thio severely. This is my artistic rendition of the way the retraction is done. When it does cause hearing loss, here is the retraction. When it doesn't cost hearing loss, the cerebellum is retracted rather than straight laterally. It's retracted from superior Lee Thio inferior Lee. So for doing this procedure in the most effective and safe way, we have a little checklist. We make sure we have a very precisely placed opening, which obviously then means the procedure is is minimally invasive as possible. We use minimal retraction, the direction of the retraction that has to be very precise so that it doesn't stretch the hearing nerve, which is the cochlear nerve. And we maintain that Iraq night over the eighth nerve as a checkpoint for our retraction technique. Here's a little video that will show you what I mean by the little pillow that we use. This is the artery that you can see is attached to, and that little knuckle right there that's pulled away was what was inventing the trigeminal nerve. And with each pulsation of the heart, that little knuckle irritated the nerve. Now we make this little pledge it of Teflon felt. It's almost like cotton candy in order to keep the Teflon felt in place, blocking the artery away from the nerve. We had a little bit of tissue glue, and that keeps the Teflon felt from moving over time. So another checklist Teflon tissue to keep the Teflon in place. We don't want the Teflon to to form the nerve, if possible. And we want to keep the TCO glue, which can be toxic away from the nerve. Here's the closure. We use a small titanium plate as opposed to putting a small piece of bone back in there which unfortunately can occasionally get infected, whereas the titanium plate rarely if ever gets infected and you can see the closure of the incision. Other pictures of conditions that we see, Uh, sometimes the nerve could be relatively severely distorted by the pulsation of the blood vessel. Here you see the trigeminal nerve with a loop of superior Sarah Beller artery behind it. Now we're starting to move that artery away, and you can see that the nerve. Now, uh, it looks like an apple core in that the narrowing of the nerve has been caused by that constant pulsation of the vessel on. Once we finally get that vessel moved away, we can easily hold it in place with the tough line. Sometimes veins can actually be causation. In fact, in my Siri's of over several 100 cases, a vein can cause the compression of the nerve in approximately 11% of cases a Sfar as the results of this surgery. The wonderful aspect of this is that there's over a 90% success rate in initial relief of pain. Failures are relatively uncommon, uh, in terms of reducing at least some of the pain and a major recurrence Onley Rikers about 2% of the time. And that major recurrence can actually be treated occasionally by another surgery and sometimes by other techniques, including gamma knife radiosurgery, which will be the subject of another talk to optimize our technique. We looked at our cases, and that's how we built those two checklists that you saw. We looked at, uh, other, uh, physicians who have reported their Siris of microvascular decompression and saw that hearing loss was reported anywhere from 0% up to 19% of cases. 19% would be very unacceptable, a za complication rate for this surgery, especially with hearing loss. So we looked at ours. We looked at over 100 of our cases, uh, in a in typical fashion, we found that the superior Sarah Beller artery was the most common vessel. Thio contact the nerve in orderto keep score. We need a scale. And that scale, as many of you know, is the barrel neurological, Uh, index and B n i index. And these are the numbers. Ah, B and I Score of one is no pain off all medications. Uh, anything up to, ah, score of three B. Which pain persists but is adequately controlled with medications is considered adequate and a success. Here's our Siri's. We had 83% had had a B and I score of one, which is quite excellent. And as you can see, uh, no more than 7% had a nun Acceptable pain score. This is a similar syndrome. This is a compression of another nerve. This is the facial nerve. We don't want to confuse the trigeminal nerve, which gives sensation to the face with the facial nerve, which gives movement to the face. And you can see in these two pictures on the left uh, a depiction of a lady that has hammy facial spasm. You'll see that the right side of her face spontaneously pulls to the right and her eyelid on the right. Uh, closes somewhat. This is considered a moderate. Um uh, severity in terms of the condition. But look on the right. That lady's got a very severe heavy facial spasm. Her eye closes all the way and her lower face deviates severely. That I closure unfortunately, can complicate driving and other activities. And so these people are actually not only cosmetically disabled, but in many instances, functionally disabled. Here is a a similar video showing the microvascular decompression of the facial. There were now on the patients left side. Those little strands that we see are is the 10th nerve that is the seventh nerve right there with the eighth nerve on top being pulled away. That's the anterior inferior, sir, Better art, and you could see that little loop that's being moved right there was touching the facial nerve just as it exits the brain step again. We use our pledge it of Teflon to hold that vessel away from the what's called the nervous exit zone of the facial nerve, and that effects a cure. Some intra operative pictures. The flow Oculus is a part of the cerebellum that once is moved gives you direct access to the cranial nerves. You can see the ninth cranial nerve crossing the loop of the post. You're in fear cerebral artery, and we move that loop of poster in fear, cerebral or artery away from. You can see the eighth nerve over to the right, and that automatically decompressed the seventh nerve since the 7th and 8th nerve art so closely aligned and you can see that depicted better on this picture, the seventh nerve and the eighth nerve are both, in effect, being compressed by that pica artery. Once the artery is transposed, we could look at the nerve root exit zone of the facial nerve and notice the indentation that was left by that constant pulsation of the pika artery. Against the nerve root exit zone of the facial nerve again are Teflon glue. We try to keep the Teflon away from the nerve. We try to keep the glue away from the nerve in the most meticulous manner. Occasionally, the vessel will not stay away from the nerve no matter what we do, and we actually can then create a sling made out of Teflon, felt loop it around the offending vessel, pull it away and attached that sling to the dura of the peaches bone. Either by way of glue or possibly a staple or even an aneurysm clip. And that successfully, uh, decompress is the nerve and satisfactory fashion and is a durable solution to this problem. Here's another example of the loop of the Pika artery and its insinuating itself just underneath the 7th and 8th nerve. We don't want to be fooled by that ICA artery on the right hand side of the nerve that is not the compressive agent. It's that looping of the pika that in dense the junction of the brain stem and the facial nerve you can see again the little knuckle of artery as it is pulled away from the nervous exit zone of the seventh nerve where the arrow is on, uh, with another sling technique, the vessel is satisfactorily, uh, removed away from the nerve and, uh, hopefully permanently kept away from the nerve. So those are two very unusual neurological syndromes. They aren't life threatening, but they are severely incapacitating patients, and the microvascular decompression is a highly effective methodology for curing both. Thanks very much