presenter Kevin Milne is battling a brain tumour which has taken him off air and left him fighting a "dreadful" lack of energy and enthusiasm.
Although the tumour in the pituitary gland is benign, Milne may need surgery to protect his eyes and other parts of his brain.
The 60-year-old TV star was diagnosed with the tumour last week, after his quality of life had deteriorated to the point where he was constantly tired and rundown and he spent six hours in an accident and emergency department.
"This thing is dreadful - it slowly winds you down. All your muscles stop operating."
He said he noticed something was awry in March, soon after his 60th birthday, when his body started stiffening up. "I had real difficulty getting out of a chair and out of a car; getting out of bed in the morning was the worst. I had terrible sleeplessness, I was feeling quite down - it was like mild depression. I thought that was because I wasn't getting enough sleep. My hands were tingling."
Last week, matters worsened when he became short of breath during a walk with his wife Linda. His heart then started pumping "really hard" and he spent six hours at hospital. Specialists later established it was pituitary failure.
Milne said the tumour "just ran me right down". "It just switches off everything, it just slowly turns you off. When it's at its worst, I feel down and I don't know what's going on. Even workwise, I raised it with the bosses that maybe my time had come - I was getting old and I was slowing down and mightily fast at that."
He said his predicament had not affected his onscreen performance. "Maybe I wasn't as chirpy as ever, but I think my performance was pretty good."
Nevertheless, some of TVNZ's research showed that viewers had noticed he was not out in the field as much for
. "I mean, I just totally ran out of energy and enthusiasm."
He said the diagnosis of his condition was fantastic because he could now get back to a "situation that I had forgotten about".
Milne, who has been away from work for two weeks, has started hormone replacement therapy. "I do feel a bit better already. I am just doing quiet stuff and letting my body rebuild."
He underwent an MRI on Thursday and is now waiting to see whether surgery is required to protect his eyes and brain. "They go to the base in your brain, using microsurgery through your nose."
There is a 50-50 chance he will need the surgery.
"When I was told I [might need] brain surgery, it was hard. I had my heart operation and to be honest, I didn't feel like another one of any sort."
Milne underwent life-saving heart surgery, including a valve replacement, in October 2004.
Milne hopes to return to work as soon as possible, but is realistic that may be at least a month away.
"On TV, you don't want to give a sucker half a chance, so I am keen to get back," he said with a laugh.