For many of his patients, Sanduk Ruit is truly a miracle worker.

Over the past 30 years, Ruit has personally restored vision to more than 100,000 people in Asia and Africa.

He has also taught his simply and inexpensive methods to countless other eye surgeons across the world, in countries as remote as North Korea.

The entire process takes around five minutes. The doctor makes a small incision in the patient’s eye, allowing him to remove cloudy cataracts that impair vision for many older people.

Once the cataract is removed, Ruit replaces it with an inexpensive artificial lens. For many of Ruit’s patients, it’s the first time they’ve seen in many, many years.

The majority of the people Ruit treats suffer from eye conditions that are mostly preventable. Unfortunately, poverty and a lack of access to public health facilities prevents many of these people from seeking treatment.

It’s a common problem in poor countries around the world. According to a recent report from the World Health Organization, 39 million people are blind worldwide. 90% of these people live in low-income areas and 80% suffer from diseases that can be prevented or cured.

As a young man, Ruit decided he would make it his mission to eradicate avoidable blindness. In 1994, he teamed up with his close friend Australian ophthalmologist and philanthropist Fred Hollows to open up a state-of-the-art Tilganga eye hospital in Nepal’s capital Kathmandu.

But many people in Nepal live in the remote countryside, and are unable to reach Kathmandu or other urban areas. But that didn’t stop Ruit. According to the BBC:

“For those who cannot reach urban areas, Ruit and his team conduct mobile eye camps in remote parts of Nepal and neighboring countries, often trekking for days and cleaning out structures like tents, classrooms or even animal stables for use as temporary operating theaters.”

Ruit, who is now 59, grew up in an extremely remote village himself. The village – located in the Himalaya Mountains – was so isolated that the nearest school was a week’s walk away.

When Ruit was 17, his sister died of tuberculosis, despite the fact that the disease was preventable. The loss motivated Ruit to pursue a path that benefited others, especially those who lack access to basic healthcare.

“I am so grateful that I can make a difference in so many people’s lives,”

the doctor says.

But despite all of his success over the past 30 years, Ruit shows no signs of slowing down, and says that there is still many things he wants to accomplish before he hangs up his surgeon’s coat.

“It’s such a small organ, the eye… and what a big role it plays. Close your own eyes and see how big.” -Dr. Sanduk Ruit

Read the full story from the BBC.