Now comes the acid test: he picks up a Styrofoam cup of water, brings it to his lips and drinks — without spilling a drop.
"That is fantastic. Fantastic," says the retired mechanical engineer from Calgary, his face a picture of wonder. "I never thought it would happen."
It's been more than 10 years since Lightfoot, 68, has been able to perform such simple, everyday tasks, the result of a condition called essential tremor.
The brain disorder, which first began about 15 years ago and progressively worsened, made his hands and arms shake so violently, he had to improvise to get food or beverages to his mouth, was unable to write anything but scribbles, and has had to rely on his wife to help him dress. Trying to button a shirt was not only agonizing, but futile.
But on Tuesday, Lightfoot became the fifth patient in Canada to undergo an experimental procedure pioneered by Toronto scientists that uses high-intensity ultrasound waves to punch a tiny hole in the part of the brain where the tremor originates.
After the more than five-hour non-invasive "surgery" — 1,024 ultrasound waves are shot through the skull and focused on a single point in the thalamus — the tremor in Lightfoot's right arm and hand were virtually eliminated.
"We're delighted," said Dr. Michael Schwartz, head of neurosurgery at Sunnybrook Health Sciences Centre, where the MRI-guided ultrasound procedure was performed.
"Everything went exactly as planned," said Schwartz, principal investigator of the Phase I study that will involve six patients with severe essential tremor. "We think we've got a good result. You can see that he was writing and he can draw a spiral. He can drink from a glass — things he hasn't been able to do for at least 10 years."
Essential tremor is not the same as Parkinson's disease, although both are marked by uncontrolled shaking in the extremities, particularly the arms and hands.
But the involuntary movements of essential tremor occur only when the muscles are called on to perform a task, such as raising a glass. When relaxed and at rest, the hands and arms don't shake; with Parkinson's, the tremor is ongoing.
The disorder can arise spontaneously or run in families — Lightfoot's late father had the condition — and it tends to strike people as they age.
To prepare for Tuesday's scalpel-free surgery, Lightfoot's head was shaved and fitted with a halo-like ring held in place with screws tightened against his skull.
A helmet-like device, which incorporates a circular tube inflated with cold water to prevent the skull from overheating, was then placed over the top of his head.
Once his head was inside the MRI scanner, doctors were able to see images of Lightfoot's brain and pinpoint exactly where to direct the ultrasound beams, which produce enough heat to destroy the targeted area of brain tissue.
"If we burn it wrong or if we're off the target," there can be adverse effects for the patient, said Dr. Andres Lozano, head of neurosurgery at the University of Toronto and a member of the research team.
Those adverse effects could include impaired speech, numbness or partial paralysis, so pinpointing the exact spot in the brain at which to deliver repeated shots of the focused ultrasound beam is critical, said Lozano.
With each "sonication," as the zaps of ultrasound are called, the shaking in Lightfoot's right hand and arm progressively diminished until it had disappeared.
Schwartz said Lightfoot will now have good function in his dominant right hand, which should make his life so much easier. (The right side of his brain, which controls the left side of his body, will be left untreated.)
"I think we will want to expand the number of patients we're going to do," said Schwartz. "We're cleared to do six, but I expect from the publicity, there will be lots more people who require the treatment. So we'll ask for approval to treat more patients."
Focused ultrasound, which has been approved for use to remove uterine fibroids and cancer that has spread to the bone, will require further testing in essential tremor before it is widely available to patients.
"Exactly when it becomes standard treatment is a little unpredictable," Schwartz said. "It depends entirely on whether there are complications, which we haven't had yet but could have in the future, or how long it lasts."
Doctors aren't sure if the procedure would have to be repeated as the lesion created in the brain begins to naturally shrink.
As for Lightfoot, he's looking forward to life with a right hand that doesn't shake and all the good things that will bring: being able to eat in a restaurant without embarrassment, not being mistaken for a drunk, and drinking coffee without a straw and not seeing it leap from the cup to soak everything in sight.
"To write again," he said. "To write again would be a major step forward. Of course being an engineer, when I lost my ability to write, it really was a huge blow. It knocks your self-esteem down.
"So it will build my self-esteem again, which is really good."