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You have been diagnosed with Chiari malformation type 1 and your doctor has suggested you undergo Chiari malformation treatment. Although your surgeon will likely recommend the procedure he or she feels is best for your specific circumstances, you may be presented with different options from which to choose. Taking the time to learn more about your condition and the treatments available can help you make informed choices about your upcoming surgery.

The information below is intended to increase your understanding by making generalizations based on other patients’ experiences. Keep in mind that because your individual case is unique to you, your experience may vary and will depend on your personal health history, the characteristics of your Chiari malformation and other important factors. If you find that anything you read conflicts with information your doctor has presented to you or raises questions in your mind, jot them down to bring up at your next appointment.

About Chiari Malformation Type 1

Type 1 Chiari malformations are typically developmental in nature. That means that your condition is not a consequence of trauma or infection, but rather something that came about as your body was growing.

As you grow, your brain and skull get larger together. If you were to look inside the skull, you would see grooves and channels shaped perfectly for the brain. However, sometimes the back of the skull does not grow large enough, and that causes an area at the back of the brain, called the cerebellum, to distort downward through a hole called the foramen magnum.

The foramen magnum is a large hole at the base of the skull, where the spinal cord leaves the brain. However, for Chiari malformation type 1 patients, that hole becomes blocked by the cerebellum. This blockage prevents the flow of a special liquid, called cerebrospinal fluid (CSF), through the foramen magnum and puts pressure on the brainstem and spinal cord. The CSF normally flows around the brain and spinal cord, but if there is a blockage, this can cause symptoms.

This blockage and pressure may be the cause of the pain, muscular, sensory, and other neurological symptoms you may be experiencing and is the reason your surgeon has recommended surgery.

Chiari Malformation Treatment Options

Although there are different procedures available, the goal of all Chiari malformation treatments is to alleviate the pressure that has built up. This will prevent further damage from occurring and could also provide relief from your symptoms. There are different ways to accomplish this goal, which can be used alone or in combination. Chiari malformation treatment options are grouped into traditional procedures and minimally invasive options.

Traditional Treatment Options

Posterior Fossa Decompression

The idea behind decompression as a Chiari malformation treatment is exactly as it sounds. Your surgeon will surgically create more space for the cerebellum, re-establishing CSF flow and alleviating pressure. There are a few different methods of decompression surgery, and your surgeon will recommend what he or she believes is right for your case.

Sometimes a small section of the back of the skull will be removed (suboccipital craniotomy) through an incision at the base of the neck in order to create more room. This can be done through a traditional dural opening Chiari decompression, which also opens part of the dura, or membrane, covering the brain and expanding it with a stretchable patch.

Another decompression technique accesses the area through a transoral or transnasal route to repair an abnormality at the base of the skull or top of the neck. This technique is used less often, and it is typically in conjunction with other surgeries for more complicated skull base deformity cases.

Cervical Laminectomy

A laminectomy refers to removing the posterior part of the bony vertebra, which helps create more space around the spinal cord. The cervical portion of the spine is made up of your uppermost vertebrae in the neck. This procedure is typically combined with posterior fossa decompression surgery to maximize the restoration of CSF flow.

Spinal Fusion

Spinal fusion surgery is typically used in addition to decompression surgery for more complex situations where spinal instability is found in conjunction with the Chiari malformation so that decompression alone is not enough to provide adequate treatment. In this procedure, the surgeon will join the skull and the uppermost vertebra of the neck so they come together and heal as a single bone, increasing stability and support. This helps further protect the spinal cord from future damage.

CSF Diversion

CSF (cerebrospinal fluid) is the fluid that bathes the brain and spinal cord. It is formed in the ventricles of the brain and follows a course down the spinal column and back up to the brain, where it is reabsorbed into the bloodstream.

CSF diversion is a way to deal with the buildup of cerebrospinal fluid. This surgery is typically used in secondary cases of Chiari where hydrocephalus (abnormally increased pressure in the skull) forces the cerebellum down to create the Chiari. In this procedure, the cerebrospinal fluid is treated by shunting the CSF elsewhere in the body (typically the abdomen), where it can be reabsorbed into the bloodstream.

Minimally Invasive Treatment Options

Minimally Invasive Chiari Decompression:

Minimally invasive Chiari decompression, uses microscopic visualization equipment and special instruments to accomplish the same goal as traditional Chiari decompression. However, this procedure does not require a patch, uses a smaller surgical incision with less tissue disruption, and typically has a shorter recovery time. Most patients who are candidates for typical decompression surgery also qualify for minimally invasive Chiari decompression.

Non Dural Opening Posterior Fossa Decompression

Non Dural Opening Posterior fossa decompression is a minimally invasive procedure that involves removal of a small portion of the skull and spine to create more space for the brain and spinal cord. The procedure is similar to a suboccipital craniotomy and cervical laminectomy but performed with microscopic tools through a smaller incisions without opening the dura as in a traditional decompression surgery.

Recovery from Chiari Malformation Treatment

Your recovery following your Chiari malformation treatment is going to be a very individual experience, with much of it depending on your individual condition and which procedure you undergo. While your doctor will be able to give you the most specific idea of your personal recovery process, it can be helpful to have a general understanding of what to expect, allowing you to prepare for the time ahead.

Recovery Following Traditional Chiari Malformation Treatment

You can expect to spend approximately 2-4 days in the hospital following any traditional surgical Chiari malformation treatment. During this time, your care team will monitor your vital signs, such as blood pressure and heart rate, as well as nerve function and any symptoms of side effects from the procedure.

When you are discharged to recover at home, you will be sent home with a list of activity restrictions, such as limitations on lifting and bending. It may be helpful to arrange for help with chores around the home, child care, grocery shopping and food preparation during this time, particularly in the first week. You will likely be very tired and will need to rest as much as possible. Most patients are able to return to work in approximately six to twelve weeks, but this will vary depending on your individual circumstances.

You will likely be given a prescription for pain medication for the first week or two following your traditional Chiari malformation treatment. Your doctor will discuss your pain levels with you at your follow-up visits and will work with you to ensure you are as comfortable as possible.

Finally, some patients may require physical therapy following Chiari malformation treatment to help with mobility and to ease discomfort. As with the rest of your recovery, this is going to depend on your individual situation and needs. Your doctor will be able to discuss with you any anticipated physical therapy following your surgery, as many patients will not require it.

Recovery Following Minimally Invasive Chiari Malformation Treatment

For patients who undergo minimally invasive Chiari malformation treatment, much of the above information regarding traditional recovery applies, just to a lesser degree. You can expect your hospital stay following a minimally invasive procedure to be shorter, that you will be able to return to work sooner and that you will require less medication to manage any pain.

These differences are because minimally invasive Chiari malformation treatments achieve the same goals as traditional surgical methods but require a smaller incision and disrupt less of the surrounding tissues. The result is that patients often experience less pain, less bleeding and less recovery time, making it an excellent treatment option for those eligible.

Most patients who are candidates for traditional Chiari malformation treatments will also qualify for minimally invasive approaches. If this is an option your doctor has not discussed with you, bring it up at your next appointment to find out if the practice also employs minimally invasive techniques and whether you might be a candidate.

Choosing an Option

Because there are many different Chiari malformation treatments available, your neurosurgeon will review the options and recommend treatment plans specific to your case. Your doctor will take many factors into consideration related to your overall health, which could have an impact on the potential success and risks of certain procedures. Some potential factors include:

  • Any previous or concurrent health conditions you may have
  • Certain behaviors, such as smoking or alcohol consumption
  • Your age
  • Your weight

There are some health conditions, including advanced age or obesity, that could affect your potential treatment outcome and lead your doctor to recommend one therapy over another. Again, your doctor will take all of this into consideration in order to make the most appropriate treatment recommendations based on you as a unique and individual case.

Putting it Together

At this point, you have a better understanding of the different Chiari malformation treatment options. If you have further questions or concerns, be sure to discuss them with your surgeon prior to your procedure. Your surgeon will be happy to review anything you want to know more about before surgery. Being comfortable and at ease with your upcoming surgery will allow you to focus on your recovery.

Chiari malformation treatments