Mark Pollock, the gifted 34- year-old Irish athlete and explorer who became the first blind person to race to the South Pole, has spoken about the trauma he has gone through since a freak accident at this year's Henley Regatta left him fighting for his life.

In the most recent update of his online blog, Pollock described how he was "petrified" before an operation earlier this month where surgeons cleared his spine of broken bone and stabilised his vertebrae with titanium rods and screws.

"Maybe it was the massive doses of morphine since the accident, maybe my fear was the same as everyone else's fear as they go to theatre. I don't know," he wrote. "But, the risk of bleeding to death or waking up with my arms paralysed, as well as my legs, consumed me. Like so many worries, it didn't happen."

Pollock, a former international rower from Belfast, who went blind after his retinas detached at the age of 22 while he was a student at Trinity College, has since made his living as a professional adventure athlete and motivational speaker.

He is the subject of an up­oming documentary to be screened on RTE, entitled Blind Man Walking, which follows his successful attempt to become the first blind man to race to the South Pole on the 10th anniversary year of losing his sight.

Pollock was attending Henley as a spectator when he went sleepwalking and fell 25 feet into the front garden of the house he was staying in last July. He sustained multiple broken bones and internal injuries in the fall, and wrote previously that he believed his back had been broken in three places.

Since the operation at the Royal Berkshire Hospital in England, during which surgeons also decompressed his spinal cord, Pollock said doctors did not know if he would get any feeling or movement back below his waist.

He added he had endured "days of demoralising pain, vomiting, an unidentified infection, endless drugs, blood transfusions and fluid running into me through needles in my wrists.

"When my wrists ran out of available veins they used my ankles. I was in some dark places in my head; I am not sure if I have ever experienced as tough a week as last week. Spirit close to breaking point, I tried, without success, to write this blog," he wrote.

"But today I emerge from the haze and I know this is going to be a very long race. And I don't know where the finish line is. The last couple of weeks were a test. Now running through my head is the great polar explorer, Sir Ern­est Shackleton's family motto: By Endurance We Conquer".

In a brief update to his blog shortly after his accident, Pollock thanked everyone who had sent him messages of ­support.