Treatment of the Adult Chiari I Malformation

  • Panagiotis Mastorakos
  • John D. HeissEmail author


Successful surgery for Chiari I malformation in adults requires appropriate patient selection, the identification of the optimal procedure for the specific circumstances of that patient, and careful execution of the surgery. The goal of surgery is to reestablish the unrestricted, pulsatile movement of the cerebrospinal fluid in the subarachnoid space at the craniovertebral junction. This is accomplished almost universally by removing the posterior rim of the foramen magnum and the arch of C1, opening the dura, and placing a pericranial graft to expand the dural space at that level.


Chiari I Syringomyelia Craniovertebral decompression Duraplasty 



This chapter is an updated version of the one authored by Dr. Heiss and the late Edward H. Oldfield, MD, in the first edition of this book.

Supplementary material

Video 38.1a

Companion videos to Fig. 38.4. (a) Operative video demonstrates the pistonlike motion of the cerebellar tonsils during the cardiac cycle with descent of the tonsils occurring during cardiac systole (MP4 1390 kb)

Video 38.1b

Companion videos to Fig. 38.4. (b) Operative video demonstrates the upper pole of the syrinx and its narrowing during systole and enlargement during diastole (MP4 1238 kb)

Video 38.2

Companion operative video to Fig. 38.5 demonstrates the pistonlike motion of the cerebellar tonsils during the cardiac cycle (MOV 12576 kb)


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Authors and Affiliations

  1. 1.Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of HealthBethesdaUSA

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