Long-term assessment of intracranial pressure using the tympanic membrane displacement measurement technique.

The tympanic intracranial pressure (ICP) measurement technique was used to assess intracranial pressure over several months in two patient populations. In the first study, 43 shunted hydrocephalic children, aged 4-17 years, were tested over a period of 18 months when clinically well. Of these 11 (26%) were later admitted with symptoms suggesting acute shunt blockage. The tympanic ICP measurement correlated with clinical and/or operative findings in 10 cases. In the second study, illustrated by a case report, repeated testing over a period of 5 months in children with chronic symptoms suggestive of periods of increased ICP, demonstrated a correlation between symptoms and ICP and helped influence management decisions. Tympanic ICP measurement in shunted children is a valuable tool in the assessment of acute and chronic shunt malfunction. Serial testing was shown to be clinically useful in the long-term management of these patients as a diagnostic indicator of pressure variation and shunt dysfunction.