Robin Williams’ widow Susan Schneider Williams has opened up on the final months of her husband’s life and his devastating struggle with Lewy body disease.

In an essay titled ‘The terrorist inside my husband’s brain’ for the American Academy of Neurology, Schneider Williams reveals that Williams was initially wrongly diagnosed with Parkinson’s, something that often happens to LBD sufferers.

Robin WilliamsRobin Williams’ widow has described her husband’s battle with Lewy body disease (LBD)

Schneider Williams writes that it was only four months after her husband’s death that she learnt he had been battling LBD. “All 4 of the doctors I met with afterwards and who had reviewed his records indicated his was one of the worst pathologies they had seen,” she wrote.

In 2013 Williams began suffering from a number of symptoms which appeared unrelated, including heartburn, sleeplessness and insomnia, as well as a slight tremor in his left hand.

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One weekend he began having gut discomfort, which Schneider Williams writes, caused his fear and anxiety to skyrocket “to a point that was alarming.”

“Not until after Robin left us would I discover that a sudden and prolonged spike in fear and anxiety can be an early indication of LBD,” she writes.

A few months later, during the filming of ‘Night at the Museum 3’, Williams forgot one of his lines and his wife describes that, “this loss of memory and inability to control his anxiety was devastating to him.”

As his symptoms worsened, Williams had told his wife, “I just want to reboot my brain” and in May 2014 he was diagnosed with Parkinson disease. “We had an answer. My heart swelled with hope. But somehow I knew Robin was not buying it,” Schneider Williams continued.

On August 11 2014 Robin Williams died by suicide in his home, he was 63. Since his death Schneider Williams has worked with the American Brain Foundation, and now serves on its Board of Directors.

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“I am not convinced that the knowledge would have done much more than prolong Robin’s agony while he would surely become one of the most famous test subjects of new medicines and ongoing medical trials,” she concludes.

“Even if we experienced some level of comfort in knowing the name, and fleeting hope from temporary comfort with medications, the terrorist was still going to kill him.”