Hyperspectral imaging of tissue perfusion and oxygenation in wounds: assessing the impact of a micro capillary dressing.

OBJECTIVE

Experimental tests of non-invasive multi- or hyperspectral imaging (HSI) systems reveal the high potential of support for medical diagnostic purposes and scientific biomedical analysis. Until now the use of HSI technologies for medical applications was limited by complex and overly sophisticated systems. We present a new and compact HSI-camera that could be used in normal clinical practice.

METHOD: We assessed the use of the HSI system on the hands of 10 healthy volunteers, looking at control parameters, and those following venous occlusion, arterial occlusion and reperfusion, including tissue oxygenation, tissue haemoglobin index, perfusion in 4-6mm depth=near infrared spectroscopy (NIR), and tissue water index. Pseudo colours used ranged from 0% (blue) to 100% (red). We also assessed differences in the wounds of three patients.

RESULTS

The results show good potential in all parameters in the healthy volunteers, which had high conformity with validated reference oximetry measurements. In three wounds, different levels of oxygenation were identified in the wound area, although interpretation of these results is complex. In Cases 2 and 3, following the application of a micro capillary dressing, improvements were seen in perfusion and reduction of the tissue water index (TWI).

CONCLUSION

The camera system proved to be quick, flexible and yielded data with high spatial and spectral resolution. These data will be used to perform a power analysis for a randomised controlled study.