The topographic anatomy (topos - a place, grapho - I write, describe; thus, topography - a description of a place) is a science that studies the spatial interposition of all the organs and tissues in different systems of this or that region of the body. The topographic anatomy is often called regional. The basis of the topographic anatomy is the systemic anatomy that studies separate systems of the organs (the general anatomy). The systemic and topographic anatomies both serve as the basis of the clinical anatomy that deals with the human body structure in norm and in pathology according to the needs of various fields of clinical medicine. The clinical and topographic anatomies are the link between the fundamental sciences and the clinical ones dealing with human diseases, approaches to their diagnostics and treatment. This is why clinical terms concerning pathological processes in one or another region of the human body are always used in manuals on the clinical and topographic anatomy.
The surgical anatomy is a part of the clinical and topographic anatomies; its aim is to describe the position of an organ in general as a subject for surgical operation, even if it is situated in several regions. Thus, for example, for surgeons, especially for oncologists, it is necessary to know the topography of the oesophagus as a whole although it consists of cervical, pectoral and abdominal parts. Plastic surgical operation for repermeability of intestines after the stomach and partial oesophagus resection in patients with cancer can be successful only with clear knowledge of the topography of the whole organ.
One must also have a thourough knowledge of connections between regions along blood vessels, cellular spaces and interstices - this knowledge helps to explain how pathological processes spread, - in particular, pyo-inflammatory ones.