The actor - who has appeared in movies such as Ten Things I Hate About You and The Nutty Professor - was hospitalised after hitting his head in a fall last April.
Miller's rep Michael Hansen has now explained that Miller went into a coma and was put on life support for one month after the accident, People reports.
"He was hovering between life and death," Hansen said. "It's a miracle he woke up... He's lucky to be alive."
Miller, who is now expected to make a full recovery after being treated at UCLA Medical Centre, had to "work on some issues regarding brain connectivity" after he came out of his coma, Hansen explained.
The married father-of-two, who is working on his podcast This Week with Larry Miller again, added: "I'm very thankful to have recovered from a traumatic brain injury so quickly."
This Week With Larry Miller will return on January 9.
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