BACKGROUND A few studies have used direct measurements of cerebral spinal fluid pressure (CSFP) using either lumbar punctures or pressure transducers to evaluate CSFP elevations as a potential etiology in patients with spontaneous CSF leaks. Limitations of these techniques include positional variation, inadequate duration of measurement, and insufficient analysis of waveforms. We propose a novel technique for more accurate measurement of CSFP in patients with spontaneous CSF leaks. METHODS Patients with spontaneous CSF rhinorrhea had a lumbar catheter placed for 24-hour CSFP recording before and 72 hours after their endoscopic surgical repair. Heart rate, electrocardiogram, respirations, and oxygen saturation are recorded in addition to CSFP. Mean CSFP as well as the pulse waveform amplitude were calculated. RESULTS Twelve patients with spontaneous CSF rhinorrhea underwent continuous CSFP monitoring. Seven patients had elevations in their CSFP of >25 cm H(2)O for at least 4% of their recording time during their continuous monitoring. Nine patients had significant oxygen desaturations associated with elevated CSFP. Pulse waveform amplitudes could average 20 cm H(2)O over several minutes in patients with mean CSFP of <10 cm H(2)O. CONCLUSIONS Perioperative CSFP monitoring provides continuous data including mean and transient elevations in CSFP that can be correlated to other measurements such as oxygen saturation. This data may more accurately identify those CSF leak patients with elevated CSFP as well as correlate these elevations to prognostic clinical information that may improve treatment and outcome after their surgical repair.