Ischemia is the medical term for an inadequate blood supply to a specific area of the body. This results in a reduced oxygen supply as blood has difficulty in reaching the target tissues or organs.Ischemia can be partial or complete.ecrosis is the medical term for the death of living cells or tissue. Necrosis occurs due to unnatural factors, as a consequence of external factors. Necrosis should not be confused with apoptosis which is natural cell death.