I have Chiari, now what?

The first thing I wanted to know when I got my Chiari I diagnosis was what my options were. 

There is no rush in deciding the best option for yourself, and if you have the right neurosurgeon, they should fully brief you on what each intervention entails. But it can be a little difficult to get all of this information together (and I read way too many research papers anyway) so I wanted to summarize my findings since I had trouble getting answers myself.

Treatment Options

No Surgery: Surveillance and/or Symptomatic Management

If you are asymptomatic, proceeding with occasional MRI surveillance and visits with your doctor regarding your condition is most recommended by current literature [2, 5].

Even if you are symptomatic, surgery may not be the right decision for you, and there is absolutely nothing wrong with that. In this case, lifestyle modifications and as-needed pain medication for flares may be the route you and your doctor decide to go.

With how quickly my health was declining as a result of my condition, I thought I would immediately jump at the chance to get decompression surgery, but I still had to think it over extensively before knowing it was right for me. It is brain surgery, after all. So if you choose surgery later, or never at all, there is nothing wrong with that. You know your body and you need to do what is best for you. 

Decompression Surgery

For patients with Chiari I who are symptomatic, especially if they show signs of cerebellar dysfunction, lower cranial nerve palsies, myelopathies, occipital cough headaches, and/or syringomyelia, surgery is most often advised to restore normal CSF flow around the foramen magnum [2, 6, 7]. The most common surgical options are as follows:

Bone-only decompression

Also known as bony decompression and posterior fossa decompression, this option most often involves a suboccipital craniectomy and laminectomy.

• Pros: Least invasive procedure, avoids CSF-related complications such as CSF leak, pseudomeningocele, and aseptic meningitis
• Cons: Since it is less invasive, there is a higher chance of needing a repeat procedure; there is also ongoing debate in the medical community about how effective this procedure alone is for long-term symptom management [2, 3, 7, 8]
  
  
  
  
  
  
  Figure 1. Sagittal (side) view of the regions of the skull (suboccipital skull) and first vertebrae (C1 laminectomy) that are most often removed during a bony decompression.

Bony decompression with duraplasty

During a duraplasty, the dura mater near the cerebellum surrounding the spinal cord is opened and a graft is placed on top of the opening to expand the space, decrease brain and spinal cord pressure, and restore normal CSF flow.

• Pros: Associated with a higher rate of clinical improvement and a lower rate of reoperation compared to bone-only decompression; especially encouraged over bone-only in patients with syringomyelia [2, 3, 7, 8, 9]
• Cons: Increased risk of CSF-related complications compared to bone-only since the dura is being opened [9]
  

Figure 2. Duraplasty with bony decompression.

Photo from "Comparison of surgical outcomes in patients with Chiari Type I malformation receiving posterior fossa decompression with and without duraplasty" by Samuel Butensky, et. al

Bony decompression with duraplasty and tonsillar reduction

Tonsillar reduction is usually a decision made during the operation if the neurosurgeon finds that the tonsils are extensively compressed or if they are pushing on other structures such as the brainstem.

• Pros: Most recent literature seems to reflect that long-term prognosis is best with this procedure (if indicated by tonsillar size) in patients with or without syringomyelia without a statistically significant increased risk of complications or reoperations compared to bony decompression with duraplasty [1, 4]
• Cons: Most invasive procedure

Figure 3. Tonsillar reduction with duraplasty and bony decompression.

Photo by Ilyas Munshi, MD

Suboccipital craniectomy, C1 laminectomy, duraplasty using an AlloDerm graft, and tonsillar reduction was ultimately the right decision for me. Based on the literature and my recently diagnosed syringomyelia, especially with how low the syrinx was in my spine, we had a feeling that bone-only would not be able to relieve enough pressure to significantly improve CSF flow in my lower spine. During the operation, once my neurosurgeon saw how herniated my right cerebellar tonsil was and how it was compressing my left tonsil, tonsillar reduction was performed as well. 

I have no regrets about my treatment plan and I am so grateful to have had such an amazing medical team through every stage of the process.

I know this is a lot of information to take in. 
So take your time, speak extensively about your options with your neurosurgeon, and please reach out to me if you want to talk about it!

Glossary

Aseptic meningitis: inflammation of the meninges (the membrane around the brain and spinal cord) that is not caused by a bacterial infection

Cerebellar dysfunction: signs include cerebellar dysarthria, muscle weakness, and nystagmus (see more in post: "What is syringomyelia?")

CSF leak: when cerebrospinal fluid (CSF) leaks out of a tear or hole in the dura

Intervention: a medical term used to describe the treatment, procedure, or other action chosen to improve a patient's health

Laminectomy: removal of the lamina (the back portion) of a vertebrae to relieve pressure on the spinal cord and nerves

Lower cranial nerve palsies: damage to cranial nerves IX-XII, which each present differently if damaged

• Cranial nerve IX palsy: inability to elicit gag reflex or swallow
• Cranial nerve X palsy: uvula deviation from midline
• Cranial nerve XI palsy: inability to turn head from side to side or shrug shoulders, asymmetric shoulder droop 
• Cranial nerve XII palsy: tongue deviation from the midline when stuck out or tongue otherwise unable to move

Myelopathy: nerve dysfunction caused by spinal cord compression (can present with difficulty walking, abnormal reflexes, loss of bowel/bladder function, decreased coordination/balance/fine motor skills, and/or weakness/pain/tingling/numbness at the dermatomal/myotomal level of spinal cord compression 

Occipital cough headaches: sharp, splitting, or stabbing pain in the occipital region (back) of the head brought on by coughing

Posterior fossa: the small space in the skull that contains the cerebellum and the brainstem

Pseudomeningocele: a rare complication of duraplasty where CSF collects outside of the dura

Suboccipital craniectomy: removal of the bone from the base of the skull (distinct from a craniotomy in which the bone is replaced after surgery)

Syringomyelia: cerebrospinal fluid-filled cyst in the spinal cord (see more in "What is syringomyelia?")

References

1. Braga BP, Montgomery EY, Weprin BE, Price AV, Whittemore BA, Pernik MN, Sklar F, De Oliveira Sillero R, Swift DM. Cerebellar tonsil reduction for surgical treatment of Chiari malformation type I in children. J Neurosurg Pediatr. 2023 Mar 10:1-10. doi: 10.3171/2023.1.PEDS22222. Epub ahead of print. PMID: 36905667.
   
   
2. Ciaramitaro P, Massimi L, Bertuccio A, Solari A, Farinotti M, Peretta P, Saletti V, Chiapparini L, Barbanera A, Garbossa D, Bolognese P, Brodbelt A, Celada C, Cocito D, Curone M, Devigili G, Erbetta A, Ferraris M, Furlanetto M, Gilanton M, Jallo G, Karadjova M, Klekamp J, Massaro F, Morar S, Parker F, Perrini P, Poca MA, Sahuquillo J, Stoodley M, Talamonti G, Triulzi F, Valentini MC, Visocchi M, Valentini L; International Experts Jury of the Chiari Syringomyelia Consensus Conference, Milan, November 11-13, 2019. Diagnosis and treatment of Chiari malformation and syringomyelia in adults: international consensus document. Neurol Sci. 2022 Feb;43(2):1327-1342. doi: 10.1007/s10072-021-05347-3. Epub 2021 Jun 15. Erratum in: Neurol Sci. 2022 Feb;43(2):1483-1484. doi: 10.1007/s10072-021-05724-y. PMID: 34129128.
   
   
3. Förander P, Sjåvik K, Solheim O, Riphagen I, Gulati S, Salvesen Ø, Jakola AS. The case for duraplasty in adults undergoing posterior fossa decompression for Chiari I malformation: a systematic review and meta-analysis of observational studies. Clin Neurol Neurosurg. 2014 Oct;125:58-64. doi: 10.1016/j.clineuro.2014.07.019. Epub 2014 Jul 21. PMID: 25087160.
   
   
4. Hu Y, Zhang M, Duan C, Song D, Wei M, Guo F. A long-term follow-up study of adults with Chiari malformation type I combined with syringomyelia. Front Neurol. 2023 Dec 1;14:1274971. doi: 10.3389/fneur.2023.1274971. PMID: 38107634; PMCID: PMC10722987.
   
   
5. Leon TJ, Kuhn EN, Arynchyna AA, Smith BP, Tubbs RS, Johnston JM, Blount JP, Rozzelle CJ, Oakes WJ, Rocque BG. Patients with "benign" Chiari I malformations require surgical decompression at a low rate. J Neurosurg Pediatr. 2019 Apr 1;23(4):498-506. doi: 10.3171/2018.10.PEDS18407. Epub 2019 Jan 4. PMID: 30611156.
   
   
6. Massimi L, Peretta P, Erbetta A, Solari A, Farinotti M, Ciaramitaro P, Saletti V, Caldarelli M, Canheu AC, Celada C, Chiapparini L, Chieffo D, Cinalli G, Di Rocco F, Furlanetto M, Giordano F, Jallo G, James S, Lanteri P, Lemarchand C, Messing-Jünger M, Parazzini C, Paternoster G, Piatelli G, Poca MA, Prabahkar P, Ricci F, Righini A, Sala F, Sahuquillo J, Stoodley M, Talamonti G, Thompson D, Triulzi F, Zucchelli M, Valentini L; International Experts - Jury of the Chiari & Syringomyelia Consensus Conference, “Milan, November 11–13, 2019”. Diagnosis and treatment of Chiari malformation type 1 in children: the International Consensus Document. Neurol Sci. 2022 Feb;43(2):1311-1326. doi: 10.1007/s10072-021-05317-9. Epub 2021 Jun 7. PMID: 34097175; PMCID: PMC8789635.
   
   
7. Pakzaban P. Technique for Mini-open Decompression of Chiari Type I Malformation in Adults. Oper Neurosurg (Hagerstown). 2017 Aug 1;13(4):465-470. doi: 10.1093/ons/opx027. PMID: 28838117.
   
   
8. Tubbs RS, McGirt MJ, Oakes WJ. Surgical experience in 130 pediatric patients with Chiari I malformations. J Neurosurg. 2003 Aug;99(2):291-6. doi: 10.3171/jns.2003.99.2.0291. PMID: 12924703.
   
   
9. Xu H, Chu L, He R, Ge C, Lei T. Posterior fossa decompression with and without duraplasty for the treatment of Chiari malformation type I-a systematic review and meta-analysis. Neurosurg Rev. 2017 Apr;40(2):213-221. doi: 10.1007/s10143-016-0731-x. Epub 2016 Jun 1. PMID: 27251046.