PRIMARY SPONTANEOUS CEREBROSPINAL-FLUID RHINORRHEA

Spontaneous cerebrospinal fluid (CSF) rhinorrhea constitutes only 3% to 4% of CSF fistulas. Nontraumatic, normal pressure CSF fistulas with resultant rhinorrhea, in which no cause can be identified, or primary spontaneous CSF rhinorrhea, is considerably rarer. Presented here are two cases of CSF rhinorrhea of this nature, including the diagnostic workup and treatment. Reviews of literature support laboratory quantitative glucose determination as the most effective and least morbid method for confirming the presence of CSF. Iodine-contrast (metrizamide/lohexol) computerized tomographic cisternography has been shown to be the most effective and least morbid method for localizing the fistual. For inactive, intermittent, small, or questionable CSF leaks, radionuclide cisternography has been shown to be more effective in identifying the presence of these leaks, although not necessarily the location. Numerous reports provide evidence to support the use of an extracranial rhinologic approach for surgical repair of the leak, as a more successful yet less morbid procedure than a craniotomy when used appropriately.