Blind swimmer in the fast lane for greatness

Story highlights

  • Tharon Drake is a 22-year-old swimmer competing in the upcoming Paralympic world championship
  • Drake is totally blind without light perception and lives with hemiplegic migraine headaches
  • Drake navigates the pool with the assistance of a "tapper" and by brushing up against lane ropes
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(CNN)At the age of 15, Tharon Drake's world was submerged into complete darkness.

It all started after a routine swim meet in February 2008. It was late, about 11 p.m., and Tharon began to notice his vision wasn't quite right. He and his dad, Shawn Drake, wrote it off as post-race exhaustion and went to bed.
    But the next morning, Tharon's dad was worried. "I was in panic mode. Something was definitely wrong," Shawn recalled. His son's vision was darkened and blurry, and Tharon could barely see a few feet in front of him, Shawn said.
    Tharon's family immediately sought medical help. No stranger to doctors, Tharon had been dealing with severe bouts of amnesia for a few months prior, and hemiplegic migraine headaches, which can be so excruciating that the pain spreads to extremities and other parts of his body.
    His diagnosis was unclear. Doctors attributed the amnesia to a rare methylation defect, which refers to problems with the body's natural mechanism of gene expression, but they couldn't explain the sudden blindness. One doctor surmised it was the result of a viral attack, according to Tharon's dad.
    Treatment began, with the goal of building up Tharon's immune system. The amnesia started to disappear, but week by week Tharon also lost more and more of his eyesight. By June 2008 he was totally blind, without any perception of light.

    Normal vision at age 14, blind at 15

    "It was tough. One year I had 100% vision...the next year I was 100% blind," Tharon said. To this day, the cause of Tharon's blindness remains a medical mystery.
    But losing his sight didn't get in the way of Tharon's life vision and purpose. A competitive swimmer since age 9, Tharon continued to push through daily swim practices with the encouragement of his father, who helped Tharon learn how to swim all over again. In high school Tharon competed against sighted swimmers. Today, he races against other blind swimmers in his para-swimming class -- S11, which indicates "a complete or nearly complete loss of sight."
    "Parents need not allow their child to become a victim," said Tharon's dad. "I used to be the one pushing Tharon. Now he's the one pushing himself."
    Tharon also refused to let his blindness become the center of his life. "Everyone has a disability. Mine just happens to be blindness," Tharon said. "But you can't let your disability define you. ...It's just part of your story."
    Tharon said blindness fundamentally changed how he interacted with the world around him.
    "After I lost my sight, it wasn't that my hearing got better, it's that I learned how to pay attention to my other four senses."

    How blind swimmers navigate a pool

    Blind swimmers race with the help of a "tapper," a person who uses a custom tool to tap the swimmer on the head when they're nearing the wall at the end of the lane. All swimmers in the S11 class are also required to wear blackout goggles to equalize the playing field, as some swimmers may have light perception while others are to