Measurements of oxygen saturation in normal human sural nerve by micro-lightguide spectrophotometry and endoscopy.

Abstract

Micro-lightguide spectrophotometry is a new technique which allows continuous deter-mination of the intracapillary haemoglobin oxygen saturation (HbO2%) from the remission spectra of small volumes of tissue. We have used the Erlangen Micro-lightguide Spectro-photometer (EMPHO II) to measure the HbO2% in human sural nerve. The measurements are made 0.5–1 mm from the surface of the nerve through a small 10mm inscision under local an-aesthetic. The lightguide, which consists of a single 250 μm illuminating and six receiving fi-bres, can be attached to the eyepiece of a small (1.9 mm diameter) endoscope via a beam splitter so the exact site of measurement can be visualised.