Non-invasive measurement of haemoglobin based on dynamic spectrum method

For the purpose of measuring the haemoglobin non-invasively, the dynamic spectrum (DS) method, which can minimize and hopefully eliminate the discrepancies among the individuals and the complicated conditions during measurement by near-infrared spectroscopy, was applied. DS is more accurate than the traditional method in haemoglobin non-invasive measurement, which was proved by theoretical derivation. In vivo measurements were carried out in 110 healthy volunteers and a criterion named the number of stable wavelengths was mentioned to evaluate the data's quality. A back propagation neural network was used to establish the calibration model of haemoglobin concentration against DS data, which were pre-processed by some special algorithms. The correlation coefficient of the predicted values and the true values was 0.907, which demonstrates proof-of-concept for the ability of the DS method to monitor haemoglobin concentration changes non-invasively.