A new method for using fluorescein to demonstrate oto- and rhinoliquorrhea. I. Sample preparation by electrophoresis and photometric identification of fluorescein.

We have described a new method for the identification of sodium fluorescein in cases of cerebrospinal fluid (CSF) leakage. To take samples, small sponges of Merocel are placed into the nostrils or external auditory canal, as indicated. They are left in situ for 12h after intrathecal injection of 5% sodium fluorescein. Fluorescein is identified by electrophoretic separation on 1% agarose gel and demonstration with the fluorescence photometer. This method of testing has various advantages: the use of small sponges enables collections of minimal amounts of CSF; potential sources of disturbance (e.g. hemoglobin, etc.) are eliminated; false-positive results are avoided; the time needed for sample analysis lasts only 10 min. All necessary materials and equipment, as well as the taking and analysis of samples, are described in detail. The method used was tested both clinically on patients and in the laboratory and its sensitivity is clearly illustrated.