Why Human Color Vision Cannot Reliably Detect Cerebrospinal Fluid Xanthochromia

Background— Visual assessment of cerebrospinal fluid (CSF) for xanthochromia (yellow color) is practiced by the majority of laboratories worldwide as a means of diagnosing intracranical bleeds. Methods— Colorimetric and spectrophotometric analysis of CSF samples for recognizing the presence of bilirubin either in low concentrations or in the presence of hemolysed blood. Results— The experiments provide the physiological and colorimetric basis for abandoning visual assessment of CSF for xanthochromia. Conclusion— We strongly recommend relying on spectrophotometry as the analytical method of choice.