There is no designated classification or naming convention for<unk> s. Because the definition of a<unk>  is so broad, the varieties of<unk> s are virtually endless.<unk> s can occur anywhere in the body. Generally,<unk> s may be classified by their patterns, their sizes, their locations, or their causes.<unk> s are sometimes also named after the person who discovered them. Some<unk> s have specialized names, such as Ghon<unk> s in the lungs of tuberculosis victims, which is named after the<unk> 's discoverer. The characteristic skin<unk> s of a varicella zoster virus (VZV) infection are called chickenpox.<unk> s of the teeth are usually called dental caries. Location<unk> s are often classified by their tissue types or locations. For example, a "skin<unk> " or a "brain<unk> " are named for the tissue where they are found. If there is an added significance to regions within the tissue—such as in neural injuries where different locations correspond to different neurological deficits—they are further classified by location. For example, a<unk>  in the central nervous system is called a central<unk> , and a<unk>  in the peripheral nervous system is called a peripheral<unk>  A myocardial<unk>  results from damage to the heart muscle, and a coronary<unk>  is a subtype that describes a<unk>  in the coronary arteries. Coronary<unk> s are then further classified according to the side of the heart that is affected and the diameter of the artery in which they form. Cause and behavior If a<unk>  is caused by a tumor it can be classified as malignant or benign after analysis of a biopsy. A benign<unk>  that is evolving into a malignant<unk>  is called "premalignant." Cancerous<unk> s are sometimes classified by their growth kinetics, such as the Lodwick classification, which characterizes classes of bone<unk> s. Another type of<unk>  is excitotoxic<unk> s, which can be caused by excitatory amino acids like kainic acid, which kill neurons through over-stimulation. Size and shape<unk>  size may be specified as gross or histologic depending on whether they are visible to the unaided eye or require a microscope to see. A space-occupying<unk> , as the name suggests, has a recognizable volume and may impinge on nearby structures, whereas a non space-occupying<unk>  is simply a hole in the tissue, e.g. a small area of the brain that has turned to fluid following a stroke.<unk> s may also be classified by the shape they form, as is the case with many ulcers, which can have a bullseye or 'target' appearance. A coin<unk>  is identifiable in an X-ray as appearing like a coin sitting on the chest of the patient.
Lesion
Eschar
Polypill
Blood blister
Papule
Target lesion
Body odor
Figurate erythema