Cough headache due to craniospinal pressure dissociation.

Two women had severe headache that would come on a few seconds after straining or coughing and would last for about a minute. Results of pressure studies showed that a difference in pressure between the ventricles and the lumbar subarachnoid space developed after coughing or straining. Decompression of the cerebellar tonsils relieved the symptoms and eliminated the craniospinal pressure dissociation in both cases.