Near-infrared Spectroscopy (NIRS) for Intracranial Hematoma Detection

The light used in the near-infrared spectrum, especially between 700 and 1000 nm, is able to penetrate the human tissue 'optical window'. Once the light has penetrated into the tissue, it is either scattered or absorbed. Light is mostly scattered by bones, skin and cerebral white matter. However, red blood cells, which represent roughly have a low scattering effect and high absorption. Utilising this principle, the emitter and detector could be used to measure the light scattered by the tissues. The 'optical density' of the tissue is calculated and by comparing the left and right hemispheres in the eight contralateral locations of the brain lobes where lesions with extravascular accumulation of haemoglobin can be detected. A NIRS device named Cerebo® was developed by Bioscan Research, Ahmedabad, India. It is a low power non risky device that can screen the patient's head multiple times without causing any side effect. The built in safety features in Cerebo® make it fail safe system for intentional as well as accidental exposure to laser beam. The average power and total power dissipation is very low. The system poses no risk to the patients who will be included in the study.

So far the overall results of detection rate of hematoma using NIRS device are contradictory. It is not the replacement of a CT scan but can help in triage. In the present research the investigators plan to do a large scale prospective study to establish the role of NIRS device in detecting intracerebral hematoma and correlate the finding with CT scan findings.