Comparison of intracranial pressure between spina bifida patients and normal subjects using a non-invasive pressure assessment technique.

A comparison of mean intracranial pressure (ICP) between 36 spina bifida patients and 24 patients with clinically normal ICP was undertaken. A new non-invasive method of assessing ICP was used throughout this study. The technique relates tympanic membrane displacement to ICP and has been shown to be a reliable measure of mean ICP by comparison with direct measures via ventricular catheters and reservoirs, subdural catheters and lumbar punctures. Using this non-invasive method the results of this study indicated that the patients with spina bifida and without a ventricular shunt have a higher than average mean ICP. The results demonstrated a significant difference (99.9%) in the measures of ICP between the spina bifida and normal populations. A significant difference (99.9%) in the ICP was also found between patients with spina bifida and with and without ventricular shunts, and thus presumably those with and without diagnosed hydrocephalus. It is suggested that patients with spina bifida and without ventricular shunts probably have higher than average mean ICP when compared with the normal population.