The good news - no associated syringohydromyelia of the cervical or upper thoracic cord to the level of the T3 vertebral body.
Cerebellar tonsils herniate through the foramen magnum at the level or the C1 ring measured at 14 mm, well above the threshold for a Chiari I Malformation.
Can anyone explain this part?
Diminished CSF signal noted anterior to the medulla.
It's awesome you don't have a syrinx. My herniation was also 14mm but it took me almost 5 years of deteriorating before I was finally diagnosed. They will probably want to do the surgery soon depending on you symptoms. How long have you been symptomatic? The herniation is like a cork and it doesn't allow Cerebral Spinal Fluid flow to be normal. So you often have some degree of hydrocephalus. It also puts pressure on your brain stem which is the biggest nerve bundle in your body. They pay more attention to Carpal Tunnel Syndrome which is also a nerve bundle problem than they do Chiari. Do you have a neurosurgeon? Did they order the MRI?