An apparatus (10) and method enables a reading of a continuous beat to beat heart rate at the superficial temporal artery to give an indication of blood pressure of the brain and blood related diseases. The apparatus (10) is non-invasive. Preferably a reading of a continuous beat to beat heart rate is measured on both the left superficial temporal artery and the right superficial temporal artery simultaneously during the same heart beat. Where the wave form measured from the left temporal artery differs from the wave form measured from the right temporal artery this may be an indication of an impending stroke or an indication that a stroke has recently happened. Further the indices of the wave forms may be used as a clinical indication of other blood related diseases.
