Lumbar puncture. Lumbar puncture (LP), also known as a spinal tap, is a medical procedure in which a needle is inserted into the spinal canal, most commonly to collect cerebrospinal fluid (CSF) for diagnostic testing. The main reason for a lumbar puncture is to help diagnose diseases of the central nervous system, including the brain and spine.
2. ratio-the relation between things (or parts of things) with respect to their comparative quantity, magnitude, or degree; an inordinate proportion of the book is given over to quotations; a dry martini has a large proportion of gin. proportion.
Ratio Definition. In mathematics, a ratio is a numerical comparison of 2 or more quantities which indicates their relative sizes. It can be considered as a way of comparing numbers by division. In a ratio of two numbers, the first value is termed the ancedent and the second number is the consequent. Ratios in Daily Life