Method for diagnosing conditions consistent with the presence of cranial blood vessel blockage and large vessel occlusions (LVO's) using the framework of a small head-harness that is transportable, field-expedient, and durable. A single pulse set using ultrasonic or near-infrared energy is broadcast into a patient's brain allowing the apparatus to perform an area scan of the brain and detect and decipher cranial blood vessel blockage and LVO signal patterns. The interpretation of the pattern lies within the internal programming which produces a binary signal as to whether an LVO is suspected or not.