A Chicago teenager traveled to Barrow Neurological Institute to undergo surgery with Dr. Michael Lawton for a cavernous malformation (sometimes referred to as a cav mal) in her brainstem.

Norah Denahan, 15, was diagnosed with the vascular abnormality during her freshman year of high school after experiencing a hemorrhagic stroke that left her temporarily paralyzed on her left side. She was told the lesion was inoperable, but leaving it alone left her at risk for another bleed—which could be life threatening or cause lasting neurological damage.

Dr. Lawton successfully removed the malformation, and Norah is back in Chicago training to become a lifeguard.

See the full story: Chicago girl, 15, makes miraculous recovery after risky surgery for rare brainstem growth