The Jamaican hit-man suffered cruciate ligament damage during a league game at Coventry in November, and was subsequently ruled out for the rest of the season.
There were fears over the long-term future of the 23-year-old as he faced an operation to rebuild the injured knee.
However, Fuller has been given the green-light by surgeons following surgery in the United States, and is expected to return to Deepdale in the next few weeks to commence his rehabilitation.
"I spoke to Ricardo who is happy," Preston chief Craig Brown said.
"The operation went well and he's delighted with the prognosis from the surgeon who says that it was a successful operation.
"Ricardo is assured psychologically and we are now quite sure physically he'll be returned to top class health very quickly."
Meanwhile North End's bid to sign Arsenal's Graham Barrett as a replacement for Fuller has now collapsed.
Lillywhite's chairman, Derek Shaw, has slammed the player's agent, who he claimed scuppered any chance of a deal.
"They're looking for a lot more than what we're prepared to pay, and with agents fees that we feel are excessive," declared Shaw.
"We're not having a gun to our head.
"We'll do the deals that we think are right for Preston North End."
