The Blinded Flyer.
To begin I got the idea from the movie 23 Blast but decided to put a Harry Potter spin on it. Takes place in third year.
What no one expected was that a dementor if given enough exposure from numerous it can take one's weakest part from them. People did not realize this because most often the weakest part of criminals was their minds which became more shattered then ever and sometimes even losing them. Others still it was their hearing or another sense but these were always counted as due to age but never from Dementor exposure.
"Mr. Potter what are you doing in my Hospital wing again!" Madam Pomfrey asked angrily she had just seen him the previous day because of a potions accident.
"Poppy I think it would be best if I explained." Dumbledore said as he walked into the wing behind Harry and the rest of the quidditch team.
"Well then out with it." Madam Pomfrey said irritably.
"Well it would seem that the dementors were able to get onto the quidditch pitch in the middle of the game and all surrounded Mr. Potter here and caused him to fall from his broom." Dumbledore started before Madam Pomfrey cut him off.
"So he fell and broke a bone again I take it?" MP said going over to her medicine cabinit.
"No that is not what happened Poppy he was just perhaps five feet from the ground. When he fell from the broom he started saying he could not see at all." Dumbledore stated angry he had been cut off.
"Did you give him chocolate?" MP asked rolling her eyes at Dumbledore's anger.
"Of course we did Poppy do you think us imbeciles?" Dumbledore asked as his voice rose.
"I'll run a few tests." MP said deciding to try to avoid argument.