Kidney shrinkage is irreversible and cannot be restored to the normal range. The kidney size of a normal person is directly proportional to his or her height, and if a patient experiences a reduction in kidney size that is disproportionate to his or her height, it means that the patient has a chronic kidney disease. The so-called kidney shrinkage is essentially due to the destruction of renal tissue and its replacement by fibrous scar tissue, which is not as large as the volume of the original renal unit. Patients usually have chronic renal failure, and since renal tissue does not regenerate kidneys, the reduced kidney volume cannot be restored, and the chronic renal failure it represents cannot be reversed.