The VAR system was approved for use at the tournament for the first time in March.
But although it has been used in domestic competitions across Europe in the past year -- including in top division of the German and Italian leagues and the FA Cup in England -- concerns have been raised about the system's readiness for the World Cup.
Busacca told a news conference FIFA had full confidence in the VAR technology but that it might not provide the degree of clarity some may be craving.
"If we say now yes to (having VAR in) this World Cup, it's because we think we are ready," he said. "But don't think that it will be perfect. We are looking to have an incredible uniformity and consistency, but don't think that technology solves the problem 100 percent.
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"In front of a video, we will always have a human person who is making an interpretation. It's not goal-line technology with a vibration. No, it's an interpretation. It can be yes, it can be no. We can discuss after the game, always.
"But I'm sure and convinced that the scandals that we remember from the past we will not see any more."
Pierluigi Collina, chairman of FIFA's referees committee, knows the pressure of officiating at the highest level, having taken charge of the 2002 World Cup final between Brazil and Germany.
However, he believed that having the ability to refer to VAR would alleviate the stress on officials in Russia.
"Psychological issues for a referee are very important," Collina said.
"It's the main reason why the referee makes the so-called home field review. Because it would be very, very difficult for someone to change the decision made on the field of play without knowing what happened. His self-confidence for the rest of the game could be heavily affected.
"That's why we are convinced that any referee with the possibility to review the incident and change his mind and change his decision will be very helpful in terms of limiting the psychological effects on himself."
Argentine referee Nestor Pitana will take charge of Thursday's opening World Cup match between hosts Russia and Saudi Arabia in Moscow.
(Writing by Christian Radnedge; Editing by Neville Dalton)
