Perilymph protein was found to be elevated over 1,000 mg/100 ml in 53 patients with acoustic neurinoma. A simple rapid microprotein test for inner ear fluid has been developed that can be used by the otologic surgeon in the operating room. This test requires 1.5μl of inner ear fluid, which is collected from the vestibular cistern in micropipets by capillary attraction. The rapid protein test has been used successfully in 15 patients and appears to be satisfactory as a method of determining approximate inner ear fluid protein concentrations.