A Chiari malformation is where the lower part of the brain pushes down into the spinal cord. This can put pressure on the brain stem, spinal cord, and obstruct the flow of fluid. There are 4 types of Chiari malformation, with Chiari I being the most common. The severity of a Chiari malformation can range from relatively mild (or even unnoticeable) to severe, with most cases being mild. Should a Chiari malformation cause significant side-effects, an operation may be required.
If symptoms do develop, they include headaches, neck pain, dizziness, muscle weakness, loss of balance, blurred vision, sensitivity to light, tinnitus, numbness and tingling in the arms, nausea, insomnia, depression and swallowing difficulties. Syringomyelia (development of a fluid-filled cyst (syrinx) within your spinal cord) is a common side-effect of Chiari malformation, and can cause pain. Cannabis can help with many of these side-effects. It is unlikely that cannabis or cannabinoids can play any part in treating Chiari malformations directly.