All Black centre Conrad Smith is expected to make a full recovery from eye surgery after having his detached retina "spot-welded" back into place to ensure there is not a recurrence.

However, a six-week "no training zone" means he will miss the All Blacks' first two Rugby Championship tests against Australia.

Smith has requested privacy in the wake of his surgery, but Hurricanes doctor Ian Murphy yesterday revealed the delicate nature of two operations last week to reattach the Hurricanes' captain's left retina.

"Conrad had a scleral buckle which is a little piece of silicon plastic, which you effectively sew on to the outside of the eye," Murphy said.

"That provides a little bit of pressure inwards . . . and combined with the pressure on the eye from the inside effectively pushes the retina back onto the globe, or eyeball if you like."

During the 90-minute procedure last Tuesday, Smith also had cryotherapy or a "cold burn" to seal off the edges of the tear.

Where he differed from a regular patient was that he went back on Friday for laser therapy, or "spot welds" to hold the retina in place.

Murphy said the chances of a recurrence were "extremely low", but the second procedure, which took about 40 minutes, provided an "insurance policy" for someone who played contact sport professionally.

The prognosis is that Smith will not suffer any future effects from the surgery.

"He hasn't lost any of the visual aspects he requires in terms of depth perception and so forth," Murphy said. "The retinal detachment as Conrad had was what we'd call quite peripheral. So it wasn't in his central vision, if you like, when we look straight ahead."

It remains unclear what caused the injury, which was usually due to "direct trauma" to the eyeball.

"Interestingly for Conrad, he didn't have that. This has come somewhat out of the blue," Murphy said. "He's in the thick of it as we can all see, but there was nothing he can specifically relate it to during that Chiefs game."

In fact, Smith only realised there was a problem after experiencing blurred vision in the days after the Friday night match. He notified Murphy on the Monday and had surgery the next day.

Exercise, including lifting weights, will be off limits for the next six weeks as movement and increased blood flow had the potential to "jiggle" the retina loose.

"No training, I would hasten to say is a cover-all term. At this stage I'd say no training means literally no training," Murphy said.

That means Smith will definitely miss Bledisloe Cup tests against Australia in Sydney and Auckland.

But, while Murphy said the 30-year-old's eye would theoretically be okay for rugby in six weeks it would be "pure speculation" for him to comment on whether he would be fit to play Argentina on September 8 in Wellington.

That will depend on his recovery, fitness, confidence and the selections of the All Black coaches.

- © Fairfax NZ News