Credit: Randy Holmes/ABC Television Group © 2012 Disney Photo: Mark and Jackson Care For a Patient on Grey's Anatomy Season 8, Episode 15

Tumors and lymph nodes and mania, oh my! If all of the medical lingo from last night's double-header has got your head spinning double-time, have no fear. We've got you covered. Here's a recap of some of the conditions covered on last night's episodes of Grey's Anatomy and Private Practice.

Erica suffered from a gliosarcoma, a rare, malignant, cancerous tumor formed by glial cells in the brain (basically cells whose job it is to support the neural cells). These cancers rarely spread outside of the brain, but they have been known to move to the blood, lungs, liver, and lymph nodes.

Bailey's patient's arm was so enlarged because she had lymphedema, a drastic swelling in the arms or the legs caused by a block in the lymphatic system. The lymphatic system is responsible for draining fluid from organs and incorporating that fluid back into the bloodstream. When there is a blockage, this fluid will build up and create swelling. The most common cause of lymphedema is the removal or damage of lymph nodes through cancer treatment.

Sheldon diagnosed Sam's sister Corinne with hypomania, a form of bipolar disorder in which affected individuals will often have intense and unpredictable feelings of euphoria and irritability. Individuals with hypomania experience no psychotic symptoms associated with mania. Hypomania usually manifests in a decreased need for sleep and a large amount of energy, as well as an outgoing and competitive disposition. Individuals with hypomania often live full-functioning lives because the condition can be treated by mood-stabilizers and monitored closely by psychiatrists.

Sources: Mayo Clinic, Wikipedia

Catch an all-new episode of Grey’s Anatomy on Thursday, February 23 at 9pm ET/PT on ABC.

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