The reason for a<unk>  may be to make a diagnosis or to treat a disease. Diagnosis The chief diagnostic indications of<unk>  are for collection of cerebrospinal fluid (CSF). Analysis of CSF may exclude infectious, inflammatory, and neoplastic diseases affecting the central nervous system. The most common purpose is in suspected meningitis, since there is no other reliable tool with which meningitis, a life-threatening but highly treatable condition, can be excluded. A<unk>  can also be used to detect whether someone has 'Stage 1' or 'Stage 2' Trypanosoma brucei. Young infants commonly require<unk>  as a part of the routine workup for fever without a source. This is due to higher rates of meningitis than in older persons. Infants also do not reliably show classic symptoms of meningeal irritation (meningismus) like neck stiffness and headache the way adults do. In any age group, subarachnoid hemorrhage, hydrocephalus, benign intracranial hypertension, and many other diagnoses may be supported or excluded with this test. It may also be used to detect the presence of malignant cells in the CSF, as in carcinomatous meningitis or medulloblastoma. CSF containing less than 10 red blood cells (RBCs)/mm³ constitutes a "negative" tap in the context of a workup for subarachnoid hemorrhage, for example. Taps that are "positive" have an RBC count of 100/mm³ or more. Treatment<unk> s may also be done to inject medications into the cerebrospinal fluid ("intrathecally"), particularly for spinal anesthesia or chemotherapy. Serial<unk> s may be useful in temporary treatment of idiopathic intracranial hypertension (IIH). This disease is characterized by increased pressure of CSF which may cause headache and permanent loss of vision. While mainstays of treatment are medication, in some cases<unk>  performed multiple times may improve symptoms. It is not recommended as a staple of treatment due to discomfort and risk of the procedure, and the short duration of its efficacy. Additionally, some people with normal pressure hydrocephalus (characterized by urinary incontinence, a changed ability to walk properly, and dementia) receive some relief of symptoms after removal of CSF.
Lumbar puncture
Ultrasound-guided lumbar puncture
Brain biopsy
Hemoencephalography
Cranioscopy
CSF tap test
Meningeal biopsy
Intracranial pressure monitoring