With increasing age, the kidney atrophy shifts the renal parenchyma pyelon index to 1:2:1. Renal Ultrasound Anatomy The kidney is a bean-shaped organ, which has usually a smooth convex lateral organ boundary.
Bipolar disorder may result from a chemical imbalance within the brain. The brain's functions are controlled by chemicals called neurotransmitters. An imbalance in the levels of one of these neurotransmitters, such as norepinephrine, may cause bipolar disorder. When levels of this chemical are too high, mania occurs.
Causes of Depression and Bipolar Disorder. The exact causes of depression and bipolar disorder are not well understood, but some combination of genetic predisposition and psychological and medical factors appears to play a role in these mood disorders. Major hallmarks of depression include a persistent low or sad mood, decreased or absent interest in almost all activities, loss of self-confidence, and a feeling of worthlessness. 2  Most people with bipolar disorder (formerly known as manic-depressive illness) experience alternating episodes of both depression and mania.