Abraham Lincoln was shot at point-blank range on 14 April 1865 by John Wilkes Booth, wielding a Philadelphia Derringer pistol. The bullet entered his head just under his left ear, went through his brain and lodged just behind his right eye. He immediately lost consciousness and lived for about eight hours. His doctors correctly said he could not be saved, given the state of medicine and surgery in 1865. There were then no possibilities of intensive care, with IV drips, assisted ventilation and steroids to reduce the cerebral swelling.
The bullet’s trajectory probably spared Lincoln’s frontal lobes and his vital brain stem areas. He would have sustained damage to his cerebellum, the area of the brain that controls movement, and we can never know what other brain structures might have also been damaged.
However, modern medical interventions could have kept Lincoln alive for a while, and brain scans might have allowed his doctors to assess the precise extent of damage. Had he survived the immediate aftermath, modern neurosurgeons could have assessed whether removal of damaged tissue, and possibly the bullet itself, would have helped him.
Whether his quality of life could have been partially restored is another, separate question, and one we simply can’t answer.
This Q&A was answered by William Bynum, emeritus professor of the history of medicine at UCL.