What does interior mean in medical terms?

In medical terms, interior means inside the body or inside an organ, as opposed to exterior which is outside. Interior refers to internal structures, organs, cavities, or surfaces that are located within body. For example, interior of chest means inside chest cavity containing heart and lungs, interior of heart means inside chambers and valves, interior of bone means marrow cavity inside bone. In anatomy, interior is similar to internal, meaning situated within, deeper, or inner. For example, interior view of abdomen in surgery means looking inside abdominal cavity. Internal medicine is medical specialty dealing with interior organs and diseases of internal systems like heart, lungs, digestive tract, as opposed to external surgery on skin. Interior in medical context can also mean inner lining, as interior of intestine means inner mucosal lining. Terms like interior capsule in brain refers to internal capsule, a white matter structure deep inside brain. So in medicine, interior generally means inner, internal, located inside body or organ, not outer surface. Doctors use interior to describe location of pain, lesions, or structures that are inside rather than on surface.