Hansel Bach

Hansel Bach was born to be a composer. He mastered the organ by age three, but his passion was the ukulele. [Of course, Taylor Swift could have learned something from Hansel.] But poor Hansel’s dreamed-of path to musical stardom took an unwanted and unfortunate turn due to his surname. In school he was railroaded into being a general surgeon by his boarding school’s headmaster who free associated an alliteration of Hansel Bach to the surname of the headmaster’s favorite historical medical figure.

Question: Can you identify Hesselbach triangle in the image?