A sterile device designed to directly measure the cerebrospinal fluid (CSF) pressure in a patient. It is a mechanical instrument that connects with a dedicated hollow needle inserted into the subarachnoid (intrathecal) space of the lumbar section of the spinal column; CSF pressure is typically displayed on a dial showing readings in, e.g., cmH2O or mmH2O. Connectors, tubing, and the spinal needle are typically included. The device is intended to be used to determine variations in CSF pressure for the purposes of diagnosing, assessing trauma, or to evaluate some other clinical condition (e.g., tumours). This is a single-use device.