It is a matter of common observation that there may be an accentuation of the signs and symptoms associated with space-consuming lesions of the brain after pneumoencephalographic, ventriculographic and other intracranial procedures.1 Such accentuation has been explained on the basis of a transient increase in the intracranial pressure with a possible shift of portions of the brain substance after these procedures.
An exaggeration of radicular pain associated with lesions of the spinal canal has frequently been observed after coughing, sneezing and straining2 as well as jugular compression.3 Utilizing this observation, Naffziger and his associates reported on a clinical test (jugular compression) for the differentiation of radicular pain of mechanical origin caused by neoplasms4 and other tumors, such as herniated intervertebral disk,5 from radicular pain of nonmechanical origin. The increase in intracranial pressure produced by jugular compression6 apparently exaggerates the mechanical stress on the nerve