Also known as: GBM, terminal brain cancer
Dr. Herman undergoes a marathon brain surgery with Dr. Amelia Shepherd to remove a massive, invasive brain tumor that has been the central arc of the season. The surgery is successful in removing the tumor but results in permanent blindness.
Also known as: TTTS
Glenda presents with a critically ill fetus due to TTTS causing severe anemia and cardiac arrest. Arizona performs fetal surgery to resect the tumor and save both mother and baby, with the baby requiring chest compressions in utero.
Also known as: Ballantyne syndrome
Glenda develops mirror syndrome, where the mother's condition deteriorates as the fetus becomes sicker, manifesting as elevated blood pressure and declining maternal circulation requiring urgent intervention.
During the fetal surgery, the baby goes into cardiac arrest requiring in utero chest compressions and epinephrine administration by Dr. Karev to restore cardiac function.
Also known as: Small stroke
Post-operatively, Dr. Herman is found to have suffered a small lacunar infarct (stroke) during or after her brain tumor resection, discovered on imaging when she doesn't wake up as expected.
Dr. Herman awakens from surgery completely blind, having lost her vision due to the tumor's invasion of her optic apparatus. This is revealed as a permanent complication at the end of the episode.