Electron microscopy (EM) is an important medical diagnostic method, particularly in the fields of kidney disease, muscle pathology, tumour pathology, neuropathology, paediatric pathology, studies of ciliary structure, parasitic protozoan infections in AIDS, viral gastroenteritis and viral infections of the skin.
Diagnostic EM requires skilled interpretation of the images seen under the electron microscope. The microscopist must be familiar with normal cell structure (ultrastructure) and the organisation of cells that make up tissues and body organs. The ability to recognise abnormalities within cells is an essential requirement of the diagnostic process.
Electron microscopes are able to discern fine detail (often called resolving power resolution or resolution) in specimens. The fineness of detail resolved can be many hundreds of times smaller than that achieved by the best light microscopes. In addition, this fine detail can be magnified many thousands of times.