Patent ID: 8391944

Claim:
A medical device, comprising: a light source configured to emit light at a plurality of wavelengths; a detector configured to detect the emitted light and generate a corresponding detected light signal; a signal conditioning module separating the detected light signal into a multi-dimensional signal, each of the dimensions of the multi-dimensional signal corresponding to scattered light received at a wavelength of the plurality of wavelengths; a digital signal processor performing principal component analysis in response to the multi-dimensional signal to generate corresponding signal data; a controller generating one of a therapy control signal and a diagnostic output signal in response to the signal data, wherein the controller detects a condition of a variable influencing the detector signal and initiates computation of a principal component by the digital signal processor in response to the detected condition, and wherein the controller detects a change in the condition of the variable and controls the digital signal processor to terminate computation of the principal component and store a currently computed principal component as the principal component corresponding to the detected variable condition in response to detecting the change in the condition; and a memory, wherein the digital signal processor stores in the memory the principal component of the multi-dimensional signal computed by performing the principal component analysis, the principal component corresponding to the detected variable condition.