 Good day. I'm Dr. Steven Pomerance and welcome to the ProScan Mentor Series sponsored to you by ProScan. Today's clip and sample from our case review series focuses on a unique but potentially catastrophic problem, a neuritic condition that expresses itself in multiple cranial nerves. I discussed this case from an imaging standpoint as well as from a clinical standpoint with my colleague and partner, Dr. Malcolm Schupeck, a neurosurgeon. I hope you'll enjoy it. Have a great day. Well, Dr. Schupeck, our next case is a is a wonderful segue into another entity that is very similar in appearance to our longitudinally growing intracanelicular schwannoma. And what was the presentation in this case? Well, you're gonna it's gonna ring a bell vertigo, tinnitus, hearing loss, facial weakness very similar to the last case, but with a vesicular rash. Wow. You have everything in this case. Dogs and cats living together, ten days of darkness, the plague, mass hysteria it's all in this case, which means there's probably more than one anatomic area involved. That's probably correct. And once again history pretty critical and I think we're gonna find that in this instance Not too many tumors that give you a rash, are there? No, not unless you're doing something else. I mean, of course, there's Caesaree syndrome, mycosis fungoides, which is a T cell lymphoma, which does give you a rash Except it doesn't give you a rash around your ears. Okay, now you're making me sorry. All right I mean there's a little bit of my internal medicine background kind of screaming out of there, but oh medicine is so much fun It's so interesting and you get to help people. It's wonderful, but let's get back to the story here is an Axial contrast enhanced T1 weighted image and there is a rash. It was described around the external ear and external auditory canal and and while I I Can't be absolutely sure that this is the rash Look at the tissues in the right external auditory canal wall and compare them with the left on contrast enhanced MR and and there's no doubt in my mind that The patient's left side or the viewer's right is a little bit brighter and enhancing So if that story of a rash or vesicles in the ear is true We have just narrowed our differential diagnosis down Dramatically, so there really aren't too many things that do that and one of them is a Zostereform infection from herpes zoster which can produce Catastrophic symptoms when it gets deeper within the brain and affects the cranial nerves the so-called Ramsey hunt syndrome herpes zoster also likes to affect the first division of The trigeminal nerve so it may affect the eyelid you may see little vesicles on the eyelid the patient has eye pain in fact severe eye pain and Compromise of the vision due to involvement of the optic nerve It is also notorious for involving multiple cranial nerves including eight The vestibular and the cochlear nerve the seventh nerve and sometimes even The fifth nerve which as we'll see in a few moments can have Catastrophic symptoms Here's a coronal projection showing our seventh and eighth nerve complex I'm going to blow it up and you all remember that the seventh nerve is up the cochlear nerve is down So in the ideal setting if there is a seventh nerve problem We'd want to see a little more preferential enhancement in the upper quadrant and we do Let's keep looking shall we Now the seventh nerve has a horizontal course It will exit the tip of the seventh and eighth nerve canal and course Anteriorly for a short distance out of a small space called the fallopian opening into the fallopian canal where it will then make a turn in the Petrus bone and That turn or that knuckle is accompanied by a little round ball at the tip of the knuckle called the Geniculate ganglion. Let's have a look at the axial and see if we can locate it and We can Here's the seventh and eighth nerve complex a little brighter. There's the cochlea This is the region of the betrosal complex and in this location is the geniculate ganglion Yet even though we allow for enhancement in the anterior portion of the horizontal nerve Due to the bathing Petrosal plexus It should not continue all the way back to the posterior third where we then see the descending seventh nerve with uber enhancement so now we have a broad distribution of enhancement external ear vesicles and We are thinking Ramsey hunt syndrome as opposed to the other major differential diagnosis, which is Bell's palsy whose organism is usually herpes simplex and Less commonly gives you vesicles somatic or skin manifestations so Bell's palsy While often unilateral can affect both sides on mr So can Ramsey hunt, but usually the clinical is more one-sided than the other and then there are other diseases That are inflammatory that affect the seventh and eighth nerve complex. See some of these we've discussed like sarcoid Borrelia from Lyme disease and Tsutsu gomuchi fever rickettsial infections and so on in that list is also syphilis which is much less common today with It's sequela known as Kogan syndrome. So now I Think our next maneuver After we've confirmed the vertical involvement of the seventh nerve is to see if there are any other cranial nerves involved The fifth nerves right here. They look normal and gray Let's see if we can spot the six nerves Here's an axial T2 weighted image. Here are the fifth nerves again The six nerves usually come out anteriorly We don't have the resolution to identify them, but there's another reason to look at the axial T2 along with the axial flare Because these patients may suffer from pontine involvement so-called rhombencephalitis Which can produce a whole host of additional symptoms So now you have an unfortunate patient who has severe ear pain and that pain often proceeds The appearance of the vesicles so it's an enigma for 10 days Then the vesicles come out then two to three weeks later the nerves start to completely crash The patient may be dizzy. They may not be able to hear they may fall They may even have Ophthalmic involvement, so they have difficulty seeing it is a horrible disease and when they fall sometimes they get injured They can get fractures. This is a potentially catastrophic injury that often results in long-term disability What do you think of the treatment of this case? I mean do you ever decompress these or is it purely antivirals and steroids? Have you ever seen one decompressed? Well, there are Reports of decompression, but it's not the common treatment for either this or for Bell's palsy and the result of those treatments is You know, there's it's not usually done. It's usually as you said medical treatment, but I am kind of interested You know just to kind of get us back to the course of illness issue and you know try to sort out this number of Diagnoses that dr. Pomerance has brought up and that he's really narrowed down to essentially one, you know still Right the patient is too sick For it to be sarcoid probably right inflammatory illness not a chronic progressive illness like a tumor and this one On the imaging standpoint doesn't look too different from that last one. We saw right I mean you'd you'd consider it of a different clinical clinical setting absolutely, okay, so That that History can really help make that distinction between this of Lyme disease rash Okay, so already just based on the history you can really help distinguish between something that have kind of some radiographic similarities and just a little bit just take an opportunity here to Talk a little bit about facial weakness. I we talking one of the early ones about the droopy eye Okay, well, how about the droopy face and that's a that's a feature of this So the first thing and that's the pretty common thing that you'll get facial weakness and the first question that the clinician Is going to have as well as it a stroke Okay, could be a stroke or could be one of these things that we've been talking about in the last couple cases and There's a simple Initial question to ask and that is is the forehead involved Okay, remember the central seventh peripheral seven So if the problem is in the cortex and it's a stroke the forehead is probably going to be spared pretty much due to the bilateral innovation Where if it's more peripheral? Okay, the whole face is going to be involved. So that's a simple question and actually just on physical exam You can get a long way toward the diagnosis. Okay now Peripheral or seventh if it's then question is well, is it nuclear? Is it in the brain or is it more peripheral? Okay, well if it's in the brain Remember here. We had the facial colliculus Bump, I guess maybe there. I thought we had a better one. Yes, we do on the T2. Yeah, I thought we had a little better one Okay, so there's facial colliculus bump is where the facial nerve is wrapping around the sixth nerve nucleus, okay? meaning That if it's in the if the problem is in the brain stem It's probably not going to be strictly a seventh nerve problem because there's all other things wrapped around it Meaning that you may get a sixth nerve problem as well or even a corticospinal tract or weakness on one side of the body problem, okay, and then more peripherally if it's involving the Geniculate ganglion, you know, that's when you start to see these things that we associate with Bell's palsy The facial weakness involves the upper and lower face can affect the lacrimal glands as well hyperacusis Okay, the nerve to the stapedius is involved in the peripheral course Okay, so just listening to the history and asking a couple of questions can help you confirm what you're seeing on the imaging and make sure that the pieces fit together Okay, and that you really on the right track with the clinician So let me make sure I have this right because that's super important clinical radiographic information if it's a stroke then The forehead area is going to be spared Generally speaking right because of the bilateral Intervation so that's the part of the motor strip that's sort of down Right next to the operculum. Okay, so there may be other things going along with that You also want to ask about speech or some other temporal lobe function So the droop is going to be more here. That's correct And and if it's a facial nerve problem, then it's going to include the forehead, right? It's gonna be more peripheral distribution once again Depending on where the problem is you're gonna have other Associations, you know meaning if it's in the brain stem gonna have other brain stem things going on It's more peripheral for example Evolving so the peripheral branches cord of timpani and taste of the anterior two-thirds of the tongue Involved and and people that have a Bell's policy will tell you that they that their taste is disordered They'll get crocodile tears. Okay, so they'll get other things along with it so you can tell by the company it keeps Where the lesion is likely to be So finally if it's in the periphery of the seventh nerve It may affect the cochlea and hearing it may affect the geniculate ganglia and they may get hyperacusis and those types of symptoms So there there are kind of four Three or four major areas that you can break down Even before you look at the scan which helps you tremendously in narrowing the differential, right? And it would help the clinician to you know once again if they can just tell you hey the faces the Forehead is is or is not involved. You know you're already you know Bit down the line on your diagnostic tree And one other caveat before we we shut this case down You know, Otalgia pain in the ear is such a common thing, you know You can you can have refer to Otalgia from the TMJ and so don't forget even on these images I mean you can see the temporal mandibular joint if you want to Here it is right here. Let's go to the other side and there is the temporal mandibular joint It's a pretty smooth structure. So there's nothing really catastrophic going on and then you've got, you know The internal causes of referred Otalgia and if you look at the the palette the the innovation therefore sensation is Is going to come from the second branch of the trigeminal nerve and then as you move back The seventh nerve and even into the adenoids it's going to be the seventh nerve then when you go down in the mandible area It's going to be the third division of the trigeminal nerve and as you move back towards the tonsil or pillars as you well Know you can get glasopharyngeal neuralgia of the tonsils So it's going to be the glasopharyngeal nerve nerve number nine and then as you move down Towards the larynx and the superior Laryngeal and recurrent laryngeal nerve now you're getting into ten and any of these areas can give you Referred autalgia a very important differential diagnosis because you could be dealing with a mass Along the mucosa of these important airway structures Can I let me give you another little autalgia tidbit sure and this harks back actually to a case that's also by the way We love tidbits. We love tidbits and this is this is exactly that One of the differentials of Ramsey Hunt syndrome could be Nervous Intermediate syndrome. Okay, because now what and we discussed before in the vascular section These vascular compressive compressive loop syndromes now the one that you associate with seven and eight Complex is hemifacial spasm But there is another syndrome called nervous Intermediate Syndrome also presumably a vascular compressive syndrome and it's going to give you a pain in exactly the same distribution Okay, because it's affecting the same back up for a second because our audience is you know They're probably not on neurosurgeons and not only that you're a sophisticated neurosurgeon. So the vascular loop syndrome Which is usually what vessel probably anterior inferior cerebellar artery for the seventh for the most common for the seventh nerve superior cerebellar For the truck for trigeminal neuralgia. So for the seventh nerve Ika does it and it'll give you Hemifacial spasm sort of a tick and then the the nervous intermediate syndrome, which by the way is called nerve seven B for you numeric lovers out there is A is a sensory nerve right primarily. It's a primarily sensory nerve There is a small motor supply associated with it. So now how does that get affected and what does that do well? it actually has components for both of autonomic and sensory and It has a distribution that is very similar right in pain right in the ear And so that syndrome is a less common than hemifacial spasm Very similar pathology. That is that compressive vessel loop Okay similar treatment that is micro vascular decompression once again Similar distribution basically because similar anatomy to Ramsey Hunt meaning same nerves affected But the history is different. That is you have a try a neurologic Presentation that is lancinating pain that comes and goes as opposed to the inflammatory So same anatomy different process gives you a different course of illness And that'll help you make the distinction whether you have a rash or not You know it can be very helpful, of course, but the fact that that comes Thunderbolt goes away really makes you think of neuralgia like a trigeminal neuralgia and remember there's even another complication, right? v3 trigeminal neuralgia v3 comes right up in front of the ear Okay, so a type types of v3 tick are going to be very similar Okay, so you could have a little work to do Thinking these things through and trying to correlate them with the images in this setting of otology that you were talking about very complex Interesting area. Well, I think you made a great Clinical point to a snooki radiologist like me if I distill I wouldn't use that if I distill it down a little bit You know in my mind lancinating pain Thunderbolt pain comes and goes its neuralgia whereas the inflammatory syndromes They crescendo the pain precedes the vesicles They crescendo and then eventually within six or eight weeks They may not completely get better, but they do get better and sometimes they go away and they don't come back Whereas the neuralgia Lancinating pain goes away comes back again Systemically sick patient versus not sick. Sure. Okay, so all of these are So onset course of illness Okay, very very helpful and as I say in this case you're dealing with identical Anatomic involvement. It's just the nature of the process itself that results in In the different clinical courses and presentations. Well, I'm sitting here together with my partner But my takeaway message to you is if you're going to be a high-level Neuro radiologist neuro imager, you better know a lot about neuroanatomy and Neurology because if you don't It's going to be very hard to correlate and figure out what the disease process is which means you got to read a little bit Should we move on to the next case? Let's let's do it