The<unk> , sometimes lumbar<unk> <unk>  or Miller Fisher<unk> , is a medical<unk>  that is used to decide whether shunting of cerebrospinal fluid <unk>  would be helpful in a patient with suspected normal pressure hydrocephalus (NPH). The<unk>  involves removing 30 mL of cerebrospinal fluid <unk>  through a lumbar puncture, after which cognitive function is clinically reassessed. The name "Fisher<unk> " is after C. Miller Fisher, a Canadian neurologist working in Boston, Massachusetts, who described the<unk> . Clinical improvement showed a high predictive value for subsequent success with shunting. A "negative"<unk>  has a very low predictive accuracy, as many patients may improve after a shunt in spite of lack of improvement after<unk>  removal.
CSF tap test
Brain biopsy
Meningeal biopsy
Lumbar puncture
Cerebrospinal fluid flow MRI
Ultrasound-guided lumbar puncture
Pneumoencephalography
Cranioscopy