Novel biomarkers of traumatic brain injury (TBI) have been discovered in laboratory animal models. The objective of this study is to find whether similar markers are detectable in the body fluids of human subjects that have sustained a TBI.

Staff of the Neurosurgical ward is asked to report to the study coordinator all patients who are hospitalized due to a suspected brain injury. After an informed consent is received, the patient has been enrolled in the study and sample collection can be started. Plasma samples are taken by the TYKSlab personnel, and the other samples by the nurses in the Neurosurgical ward. The sampling will be organized so that all the samples from a patient are preferably collected at one event. Samples will stored in the TYKSlab at the temperature of -70 °C. Collection of a sufficient number of samples (patients) will take a few months, and subsequent analysis by the Sponsor a few months. All the activities will be done during the years 2016 to 2017.

When the samples of 24 subjects have been collected, they will be transferred to the Sponsor who will ship them further to the sub-contractors. The results received from the research laboratories will be evaluated by the scientist team at Medicortex Finland Oy. The results will be published in a scientific journal, when considered to be of high enough quality and impact.

Inclusion Criteria:

• Patient is hospitalized because of a head trauma and suspected TBI.
• Age 18 or above. The subject (including the control subjects) must be an independent adult who is not under guardianship.
• The patient, or the next of kin in the case of an incompetent person, has signed the Informed consent. This concerns the control subjects, too.
• The samples can be collected during regular office hours.
• The patient needs lumbar puncture for treatment reasons. This is not a limiting criterion however. If it is difficult to find an adequate number of patients for lumbar puncture, CSF samples of some patients can be omitted after the study coordinator's consideration.

Exclusion Criteria:

• The subject has been found positive for HIV or hepatitis-B in the involved laboratory studies.
• The subject has a chronic mental disorder which is mentioned on the sickness insurance card.

Study population will include patients that are hospitalized due to a suspected traumatic brain injury. Identical number of healthy volunteers will serve as controls.