Assessment of oxygenation and perfusion in the tongue and oral mucosa by visible spectrophotometry and laser Doppler flowmetry in healthy subjects.

ABSTRACT

UNLABELLED Use of Visible Light Spectrophotometry (VLS) and Laser Doppler Flowmetry (LDF) is currently being studied by the authors to assess the viability of tissue margins in colon resection and to assess mucosal oxygenation in the colon. Thus, as a preliminary study it was necessary to evaluate whether there is any systematic inter-probe variability of the measurements by VLS and LDF. The oral mucosa was used as a model. METHODS: SO2 with VLS (Whitland Research RM200) and blood flow with LDF (Moor Instruments DRT4) were measured at 10 sites each on the tongue and oral mucosa of 10 healthy volunteers at 0, 6 and 24 hours using 3 different probes for VLS and 2 probes for LDF. RESULTS: The results showed that the SO2 measurements by VLS using the different probes on the tongue and mucosa were significantly correlated (P < 0.05). SO2 values at 6 hours were significantly higher than at 0 and 24 hours (P < 0.05) in all but one case. SO2 measurements were not correlated with LDF. LDF measurements by the 2 probes were correlated significantly (P < 0.05) but the standard deviations were very large. CONCLUSIONS: SO2 measurements on the oral mucosa are reproducible. Due to the large variations in LDF, VLS is likely to be the more clinically useful tool for identifying mucosal ischaemia.