Treatment: Surgical Decompression
Suboccipital craniectomy
A suboccipital craniectomy is the removal of a portion of the occipital bone at the back of the skull, the core bony step of Chiari decompression.
In short: Suboccipital craniectomy
- It is removal of part of the occipital bone at the back of the skull.
- It enlarges the space at the foramen magnum.
- It is the core bony step of posterior fossa decompression.
- The amount removed is carefully judged.
What it is
A suboccipital craniectomy is the surgical removal of a portion of the occipital bone at the back and base of the skull (below the back of the head, around the foramen magnum). It is the core bony step of posterior fossa decompression for Chiari malformation.
Understanding Suboccipital craniectomy
In this step, the surgeon removes a defined area of the occipital bone (commonly described as around a few centimeters in size) to enlarge the space at the foramen magnum and relieve crowding of the cerebellar tonsils. The amount of bone removed is carefully judged: enough to relieve the crowding and restore CSF flow, but not so much that the cerebellum could sag into an overly large opening (cerebellar ptosis or slump). The suboccipital craniectomy is often combined with removal of the back arch of the first vertebra (C1 laminectomy) for additional room. This bony decompression is the foundation of the surgery, whether or not the dura is subsequently opened. Understanding suboccipital craniectomy clarifies the core bony step of Chiari decompression and why its extent is carefully judged.
Why it matters
Understanding suboccipital craniectomy helps families see the core bony step of Chiari surgery — removing part of the skull to enlarge the space — and why the amount removed is carefully judged to avoid complications.
Common questions
What is a suboccipital craniectomy?
Removal of part of the occipital bone at the back of the skull.
What does it do?
It enlarges the space at the foramen magnum.
Why is the amount carefully judged?
Too much can let the cerebellum sag (cerebellar ptosis).
Bottom line
A suboccipital craniectomy removes part of the occipital bone to enlarge the space at the foramen magnum, the core bony step of Chiari decompression.
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