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.
A ratio is a statement of how two numbers compare. It is a comparison of the size of one number to the size of another number. All of the lines below are different ways of stating the same ratio. If you fill in one of the lines below, this selection will explain a few things about your ratio. Fill in only one line here.