A cerebral aneurysm is a weakened portion of an artery in the brain. When a cerebral aneurysm ruptures, a specific type of bleeding known as a Subarachnoid Hemorrhage (SAH) occurs. The diagnosis of a SAH is made only after an aneurysm ruptures. Unfortunately, there is no rapid method of screening patients for the presence of cerebral aneurysm, and literature indicates that in North America, approximately 30,000 people annually suffer an aneurismal SAH. In addition, one-third of patients experiencing a SAH are initially misdiagnosed. Having ruptured once, aneurysms is statistically more likely to rupture again. Therefore, these patients are subjected to the risks associated with aneurysm re-rupture. For those individuals with a suspected SAH, a Computerized Tomography (CT) scan of the brain usually demonstrates evidence of bleeding. However, in a considerable portion of people, a CT scan is unable to detect the blood that has escaped from the blood vessel. CT scans are less effective when used more than 12 hours after the rupture of an aneurysm. For cases, when a SAH is suspected despite a normal CT scan, physicians make the diagnosis by analyzing the spinal fluid collected by performing a spinal tap or Lumbar Puncture (LP), and this procedure is considered equivocal for diagnosing SAH. The inability to definitively diagnose SAH from LP results is largely attributed to technical limitations which inhibit the quick and objective evaluation. The possibility of a so called traumatic tap, that introduces blood into the Cerebral Spinal Fluid (CSF) sample, has limited the reliability of using a spinal tap to differentiate a common headache from a probably SAH. Thus, for those individuals with a sentinel (or warning) hemorrhage, detection within the first 12 hours is paramount. Currently, clinicians must rely upon a three-tiered pathway (clinical history, CT scan evidence, and lumbar puncture results), to diagnose SAH and differentiate it from a traumatic tap. To help the physicians distinguish between a traumatic spinal tap and a possible SAH, a fast and an effective point of care diagnostic instrument is required. This thesis describes the software and hardware components of such a diagnostic instrument. Bilirubin, which results from the chemical decomposition of whole blood, can be detected by differentiating its optical signature from that of fresh blood. Since elevated levels of bilirubin occur starting 10-12 hours after a cerebral aneurysm rupture, the presence of bilirubin in a spinal fluid sample along with an intense and persistent headache can be a clear indicator of a probable SAH. In this thesis, a diagnostic system is implemented that is based on visible spectroscopy that quickly and objectively differentiates low-blood volume SAH from a traumatic spinal tap. The system integrates innovative hardware and powerful software interface. This technology provides clinicians, with the resources necessary for assessing patients with suspected aneurismal SAH beyond the current 12-hour limitation imposed by CT scans. Furthermore, this method improves patient care and results in rapid and appropriate treatment of the patient. To perform this diagnosis, bilirubin is quantified in human CSF over a range of concentrations. The software component explored in this thesis includes algorithms in various domains, from statistical to a control theory based mathematical model. These algorithms account for the noise and distortion from metabolites in CSF and blood, leading to the quantification of bilirubin and methemoglobin spectroscopically. In addition, the configurations for a hardware platform are introduced, including a PC - spectrometer, which are portable and user-friendly and composed of specific components designed to have the required sensitivity and specificity. Finally, the prototype uses purpose built algorithms contained within the platform, such that physicians can use it in the hospital as a point of care diagnostic instrument.