Featured are methods, apparatus and devices for detecting a hematoma in tissue of a patient. In one aspect, such a method includes emitting near infrared light continuously into the tissue from a non-stationary near infrared light emitter and continuously monitoring the tissue using a non-stationary probe so as to continuously detect reflected light. The near infrared light is emitted at two distances from a brain of the patient, so the emitted light penetrates to two different depths. Such a method also includes applying a ratiometric analysis to the reflected light to distinguish a border between normal tissue and tissue exhibiting blood accumulation.