The endangered Olive Ridley Sea Turtle receiving care at Wellington Zoo's The Nest Te Kohanga had a CT scan today at Pacific Radiology.
The 25kg turtle was discovered at Lyall Bay beach on Saturday.
It is believed Ridley, as she has become known, was caught in strong currents.
Normally found in tropical waters, she was suffering from hypothermia, shell damage and dehydration.
Today's scan revealed clear lungs and no internal damage or blockages.
Zoo veterinary manager Dr Lisa Argilla was pleased with the results.
"The CT results revealed no underlying injury or damage, and her lungs are clear," she said.
"Looking at the scan results alongside her activity over the last few days, we are happy with how she is progressing."
Despite the good news, Ridley is still considered to be in a critical condition as reptiles can take a long time to recover from hypothermia, and their condition can deteriorate quickly.
It is still not known if Ridley's digestive system is in working order, but the species usually go for long periods without eating, so the veterinary team say it an inability to eat will not impact on her ability to recover.
"Ridley's movements suggest she is getting stronger, and every day that she keeps going is an encouraging sign," said Dr Argilla.
"We'll see how she goes over the next few days, but she may be able to do some swimming in her pool next week. Once she is medically fit, we'll work with Kelly Tarlton's to rehabilitate Ridley so she can be returned to the wild."
The 19-year-old was found in a remote area in the hills of Upper Hutt.