One of the jobs of superheroes is to save lives. Some do it in more ways than one. A few heroes are trained to be conventional medical doctors, so they can perform medical treatment in the absence of healing powers. They're not too common, so the "doctor" superheroes need more appreciation.
The daughter of Sinestro and love interest of Green Lantern Kyle Rayner, Soranik is a trained neurosurgeon. She becomes a member of the Green Lantern Corps.
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The Sorcerer Supreme of Earth was a former neurosurgeon whose hands were injured in an accident, causing him to lose his skills. Desperate to restore the use of his hands, his search for solutions leads him to the occult. He encounters the Ancient One, the Sorcerer Supreme of Earth at the time. Strange soon matures and inherits the mantle of Sorcerer Supreme. He is also a martial artist aside from retaining his neurosurgeon skills.
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Charles McNider, a surgeon, was operating on a vital witness for a case when a grenade was lobbed into his clinic. His patient was killed while he was blinded. However, he discovered his eyesight was reversed: he was completely blind in light, but his eyesight was perfect in complete darkness. He decided to become a crimefighter, Dr. Mid-Nite. An owl that flew through his window on the night he discovered his ability, he adopted as a sidekick, while he created his own owl-themed costume. see more on Doctor Mid-Nite
During the earlier part of the Thor comic series, the thunder god was transformed into a human named Donald Blake, a physician. It is unknown whether he retained his medical skills are retained when he transforms into Thor.
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