Credit: Danny Feld/ABC Television Group © 2010 Disney Photo: Meredith Grey on the Grey's Anatomy Musical Episode on March 31, 2011

There's only one hour allotted for each episode of Grey's Anatomy, so not everything can be explained to those of us who didn't go to medical school. But you don't have to be in the dark! We've done some digging and uncovered a bit of info about the medical cases in this week's episode.

Mark (Eric Dane) was all jazzed for he and Jackson (Jesse Williams) to conduct a cross-facial nerve graft. This operation is used to help correct facial paralysis. In this procedure, a nerve from the leg is attached to the non-paralyzed side of the face to become activated, and then transferred to the paralyzed side of the face to mimic the normal side's functions. This can help a facial paralysis patient smile, for example.

Meredith (Ellen Pompeo) found that Louise's common duct was dilated by 16 millimeters. The common bile duct is a duct that transmits bile, a fluid that aids digestion, from the liver and gall bladder to the small intestine. It is formed when the cystic duct and the common hepatic duct come together, and then the common bile duct is then, in turn, joined by the pancreatic duct. We know; we're thinking the same thing — so many ducts, so little time!

Henry was inspired (and more than a little turned on) when Teddy (Kim Raver) carried out a modified Fontan procedure, an operation to treat infants with congenital heart defects in which a new passageway diverts blood from the right ventricle of the heart and directs it straight to the lungs to receive oxygen.

Sources: PRWeb, MedicineNet.com, Wikipedia

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