 Good morning, everybody. I'm Nico Rompilio. I'm one of the first-year residents. I'll be talking about posterior Fossa syndrome today. So last month I was still consulting and neurosurgery called me to see a 22-year-old woman with a dysconjugate gaze, bilateral up-gaze palsy, and cranial nerve six palsy. So this 22-year-old had a history of a congenital hydrocephalus, and she had a right VP shunt. She also has a history of a spina bifida. Her mom says that she has had eye problems like this whenever her shunt malfunctions. Her surgical history includes a cariat decompression, again the VP shunt, with multiple revisions. The most recent one was in March. She also had a lumbar spinal cord detethering in July in two C-sections. No known drug allergies. Mother had anxiety. She's from Idaho, and she's taking Haldal and Xanax IV anxiety. So her history is a little bit complicated, but again in July she had that lumbar cord detethering, but she developed MSSA cord abscess. Now when she came to the university as a transfer, she already was having one to two weeks history of headaches, neck pain, clumsiness, or incordination of her upper extremities and possible double vision. She was found to have a cervical syrinx. On the 24th she had these eye problems that neurosurgery noted, including the bilateral up-gaze palsy and the cranial nerve six palsy. And just some note, which is going to be important later, that she was so fully alert and oriented at this point. She was found to have hydrocephalus, acute hydrocephalus, and necessitating emergent shunt removal, and an external ventricular drain was placed that day. And then several days later she developed some tremors. Psychiatry saw her stop Haldal. And most important for this talk is that she stopped talking and psychiatry did not think that this was a psychiatric problem. They had an EEG and showed some slowing without seizure activity. Neurology was consulted. They noticed some rigidity and they were concerned for NMS. Finally, she had a new shunt placed in the left and we were consulted on the 7th. So when I saw her on the 7th, just generally she had her eyes open. She would not respond to commands, but would intermittent blink to questions, could not get a visual acuity, visual fields. Her pupils were equal in reactive light without an APD. I'll show a movie for her movements, but the rest of her exam is unremarkable. And her optic nerves did not have any papillodema. So I'll just show you a movie. I want you to look to the left and look to the right. I'll show it one more time. I want you to look to the left and look to the right. I just wanted to point out that her eyes, pointing down and in and she couldn't move to have ABduction nor up gaze. So now I'm going to review several of her images kind of temporally as well. So when she got admitted to on this 22nd, what she had was she had that right VP shunt and she had slit ventricles. I just want to put your attention to that red arrow, which is in the 4th ventricle, which is normal at this point. So now when she developed the disconjugate gaze policies on the 24th, they had an MRI and showed that new hydrocephalus with massive dilation of the 4th ventricle and one of those arrows right there. Then she also had a flare hyperintensity within the midbrain in that other arrow. So now after that, she got the left, she got the EVD and I'm not showing the CT scans, but she got better in terms of the hydrocephalus. One day before the onset of that she stopped talking, she had acute worsening of the hydrocephalus, again shown in CT here. And then the next day they got an MRI and showed and this is important for my talk as well that on axial and or on flare and T2 in the cerebellum, kind of in the midline and the vermis, there is a hyperintensity as well in the T2 image. What I'm pointing right here is the dentate nucleus that kind of serrated structure right there. So the differential diagnosis at this point that we thought about was a bilateral cranial nerve 6-palsy from the elevated intracranial pressure because of the up-gaze paralysis. We also thought about dorsal midbrain syndrome because of the high intracranial pressure and kind of pushing in the brainstem could have also horizontal-gaze palsy due to stretch of the pons. She was diagnosed with meningitis so this could possibly another cause of her symptoms. Malignancy in stroke is less likely at this point. Now, but one thing that didn't make sense was the mutism, why she stopped talking and one of the thoughts that we had was posterior fossa syndrome. So posterior fossa syndrome, so this was one of the first reported cases was in 79 and showed a mutism as a reversible complication in children after posterior fossa surgery, especially for medulloblastomas. The hallmark finding in PFS is cerebellar mutism, which usually shows up as a complete absence of speech and preserved consciousness like we see in our patient. Now, the studies are really all over the place and really small studies, but the incidents report anywhere from 1 to 24% of children who have medulloblastomas. Most of these cases, patients have medulloblastomas and there's around 200 of these in the pediatric literature. And the adults, this is a rare event or at least rarely reported and only 16 in the literature. One of the first described ones was in 91 where a 20-year-old with medulloblastoma and they took it off. One of the reasons this is rare in adults, one of the hypothesis that adults just don't present with medulloblastomas. So what is the natural history of PFS? What happens in this disease from the studies? We know that after surgery there's kind of a delay and onset of the mutism in 1 to 6 days. And then the mutism usually gets better a few weeks to 6 months and is followed by this R3 that can last a little longer. It's accompanied sometimes by motor disorders such as ataxia and this can even take longer to recover. And finally they can also have orpharyngeal apraxia which they refuse to eat or have difficulty swallowing. The visual problems reported in PFS is very limited as well but one is persistent eye closure without a cranial nerve or ocular motor nerve palsy. And like what we see and at least partially what we see in our patient is also been reported a horizontal gaze palsy. People have looked at risk factors for developing posterior fossa syndrome and that's a little small but what I want to draw your attention is that the risk factors that we think are significant includes having a midline tumor location which usually happens in medulla blastoma. The other risk factors medulla blastoma tumor type but I don't think it's intrinsic to the tumor itself but just its location anatomically. Again there's other studies looking at other risk factors but one thing that I just again want to draw your attention is that people don't think or in children preop hydrocephalus does not seem to be a risk factor for predisposing for PFS. So what's the path of physiology? There's several hypothesis. One is a lesion in the dentate nucleus. So I really like this picture. So this is the cerebellum and deep to the cerebellum is the dentate nucleus thought to be controlling or coordinating speech the motor function. And one of the studies that suggest this was a classic paper back in 1975 where these authors basically stereotypically lesion the dentate nucleus for this kinetic movement disorders and they reported two patients that had complete absence of speech. So that's one of the studies that support this hypothesis. The other hypothesis is a lesion in the mermis which is midline to both the dentate nuclei. And again, this is because you know whenever people do surgery and in size midline they think that more patients develop cerebellum mutism. But I think one of my, from what I've read my favorite hypothesis is basically a lesion anywhere in this tract the dentitothalamocortical tract and it's just a more unifying hypothesis for me that lesion anywhere in this tract can cause mutism. You know, as you probably guessed there's no treatment for this. People have tried dopamine agonists like bromocryptine but none really have shown so far to decrease the duration of the symptoms. And what's most important is just counseling parents on the duration and possible long lasting speech and language deficits. So what happened to this patient after I saw her on September 7th and so I saw her two days later with that improvement of her eye movements on the 12th she was able to talk and generally improve exam, you know of note she said this day that she was scared to talk because she may lose it again. Three days later I was able to get a better exam and she still had that minus four up gaze deficit and so minus three in ABduction. She had vertical nystagmus and she was already complaining of double vision so we recommended patching. So we saw her last week in neurophthalmology. I'll show you the movie again of what she looks like but basically she had an alterated skewed deviation on lateral gaze and mild isotropia. She still had an NG tube in place. She was a little unsteady on her feet. She was still in rehab but she was speaking normally and this is what she looked like last week. She had a little bit of up beatness diagnosis. So her last imaging was this and just to note it's pretty remarkable you know that you know the sites of what we think is the pathology. This is not very good image but in T2 it's a little better. We see resolution or resolved hyperintensity in that region especially in the dentate nucleus. So just a summary for this so this is a 22 year old with congenital hydrocephalus developed meningitis VP shunt failure and hydrocephalus five days after removal of her shunt she developed cerebellum mutism that lasted for 10 days. We still think at this point that the acute hydrocephalus likely explains the bilateral cranial nerve 6 palsy but the cerebellum mutism may be secondary to damage to the dentate nuclei or the cerebellum vermis and supported by the imaging findings. Now the improvement of her symptoms do correlate with improvement of the imaging findings as well. And finally as far as we know this is the first case describing the case of cerebellum mutism from hydrocephalus and maybe a variant opposed to your phososyndrome. I'll take any questions. Thank you. For cerebellum mutism I'm sure they could they've had a lot of motor disorders but usually it's like trunk a lot taxier from what I've read. I would think with their ataxia it's very hard for them to coordinate their hand. You know in that movie it really looked to me like she had a paranoid syndrome. It looked like convergent retraction and astagnosis. I wonder if she had both. Yeah we definitely talked about that as well early on. Yeah I think that she did. Sort of like a because normally a dorsal migraine wouldn't give you such a profound abduction deficits. Right. But it would certainly give you the down and in eyes and in the sunsets and in the sunsets sign. But I just wanted to NMS the neuroleptic malignant syndrome in case somebody didn't catch that except it's a rigid change of mental status which can occur with neuroleptics like how long. It's a idiosyncratic reaction. It can be very dangerous, somewhat related to malignant hyperthermia. But I think it was really extraordinary how much better she was you know a month later she's literally walking around the clinic and in prime position not even to public it was really amazing recovery. Without any treat? Well just getting the shun thing taken care of once they got that done and just to clarify also the reason that they removed the shun I mean you say she's got a acute hypercephalus why would they take out the shun well it's because she had meningitis so they were trying to remove infected hardware. They took out the shun and they didn't need VD which theoretically should take care of the problem but that was when things got out of control. I think I want to point out the neurosurgeons did not believe that this was the cause of her mutism and the neuro-optimology department was the one that helped them help the patient identify this so big props to the neuro-optimology especially. Yeah because it's never been reported before that's unreasonable. No I'm not saying that they but I'm just saying that it's always nice to you know think outside the box in terms of helping in team approach of care. And I think the other the take home message from we had a lecture on this at the North American Appalachian Society last year was a pediatric neuro-oncologist talking about bad stuff that happens to kids and the take home message that they were proposing was that although mutism is pretty scary the rule is recovery. It may take a while but you know not all hope is lost I mean when your child suddenly stops talking completely stops talking that's got to pretty scary and oh no permanent brain damage all that kind of stuff it is it is very reversible phenomenon and it's very important to recognize it and reduce the pre-cap factor of little children in the hospital who quit talking because that can be very very scary obviously. It's interesting to me that people that get like a stroke and have an expressive invasion I think it's still kind of talk. Yeah they can make noise. Whereas these people are mute they're mute and she was in a little bit of dire straight to be able to tell exactly what she could understand but she didn't understand what was going on she just couldn't speak at all and what Niko said was I thought very interesting was when we were examining her as she was getting better she said that she didn't want to do a lot of the neurological exam because she was afraid that if she stopped talking she would forget how to talk again so I think to her the experience was that she couldn't remember how to talk or she couldn't make herself talk so she was probably very aware of what was going on. So I just have a quick question for the Neurology department is there anything different that you guys are doing in the last year so that I'm an owl that you would recommend or I mean because honestly it's hard in the community and in touch with everything so take advantage of the opportunity to know is there anything different that you're doing any treatments that have changed or anything that you would acknowledge you would be still upon? Well this is a great opportunity I think to advertise the acute non-eridic AION study that we're participating in we need to get patients in within probably 10 days would be good because they have to be randomized to their treatment by 14 days which in normal thinking would be 13 days the way they count it that's one of the things that's going on and I think the other thing that from my perspective that there's getting to be growing awareness of weird autoimmune encephalopathy visual complaints that sort of stuff it's a growing field it has been in its infancy and it's actually beginning to take shape the university has a large autoimmune neurology department which encompasses multiple theroses but a lot more as well what about from your perspective? the results of the IHTT I think it came out in the last year just to sort of reinforcing the role of diamox in the treatment we've got the apathetic favor of hypertension there's not a big trial there are a lot of papers that are published on that were you also of the new same just a comment to dovetail of what Trent asked so this is one of our most specialty case series grand rounds they've been very very popular and attended by former residents and other community faculty one thing that we're asking this year that Adam Jordan said did five to ten minutes at the end of the case series we're just an update the last year what's new, what's coming down the pipeline what are the things that we need to know so next month the 30th of November is our plastics so again Dr. Crone, Dr. Patel just five to ten minutes at the end in addition to the cases presented and then the Glaucoma Fellows would you just tell the Cornia Fellows that in December five to ten minutes again, same thing, five to ten minutes of an update would be really helpful and I do just want to acknowledge the neuro-thermology team they always do a fantastic job with education and training their case series is exactly what we want Glaucoma to do a great job last month so I want to give all the speakers and neuro-thermologists a big round of applause