A biopsy that is performed by using a punch, an instrument for cutting and removing a disk of tissue. For example, a punch biopsy of the skin may be done to make a diagnosis of skin cancer.
- Puncture wound
An injury that is caused by a pointed object that pierces or penetrates the skin. Puncture wounds carry a danger of tetanus.
- Puncture, lumbar
A procedure in which cerebrospinal fluid is removed from the spinal canal for diagnostic testing or treatment. Abbreviated LP. The patient usually lies sideways for the procedure, although LPs in infants are often done upright. After local anesthesia is i
The opening of the iris. The pupil may appear to open (dilate) and close (constrict), but it is really the iris that is the prime mover; the pupil is merely the absence of iris. The pupil determines how much light is let into the eye. Both pupils are usually of equal size. If they are […]
- Pupil dilation test
An procedure that enables an eye care professional to see more of the retina, the light-sensitive layer of tissue at the back of the eye. Dilating (widening) the pupil permits the retina to be examined for signs of disease. To do this, drops are placed into the eye to dilate the pupil. After the examination, […]
One of the two classes of bases in DNA and RNA. The purine bases are guanine (G) and adenine (A). Uric acid, the offending substance in gout, is a purine end-product.