1 What can histology and histopathology tell us?
Histology is the study of tissues and their structure. Disease processes affect tissues in distinctive ways, which depend on the type of tissue, the disease itself and how it has progressed. Histopathology, the study of tissues affected by disease, can be very useful in making a diagnosis and in determining the severity and progress of a condition. Histopathology units are found in most hospitals and there are also independent private laboratories. The services provided by these laboratories can be accessed by general practitioners (GPs), although the range of tissues that a GP can send for analysis is much more limited than those coming from a hospital surgery or from a mortuary. Because of the great variety of tests that are available and the high level of skill that is needed to carry them out and interpret them, many laboratories specialise in particular tissues or types of diagnosis. For example, a neuropathology laboratory will focus on understanding diseases that affect the nervous system. Units often work in groups across regions to provide as broad a range of services as possible. Even so, only the most diagnostically useful tests are generally available in hospital laboratories; research laboratories use many histological techniques that are limited to specific projects.