NOT many people can say that their life was changed in less than half an hour; but Flossy Mtambo can.

She is one of the examples produced by Sightsavers to help promote its new A Million Miracles fund-raising campaign.

Mrs Mtambo, aged 71, lives in Malawi. Her eyesight had faded gradually over several years, to the point where she could barely see more than a metre in front of her. She could not read, or farm her land for maize. As a consequence, her husband was forced to work less in order to look after her, throwing the couple into poverty.

The cause of her near-blindness was cataracts - a build-up of protein which clouds the lens of the eye and prevents light from reaching the retina. It afflicts as many as 80 million people worldwide, and is largely the result of ageing.

Yet it is both simple and cheap to fix, requiring only a short half-hour outpatient operation to exchange the clouded lens with a plastic one.

Mrs Mtambo's bandages were removed a few days after the operation. "Before the operation I was living without really knowing what was going on around me," she said.

"I was excited just to see my house for the first time in years. I went inside and picked up my favourite book and started to read."

Sightsavers is a UK-based charity. It has performed the same operation in more than 30 countries. Its new campaign to give one million people their sight back by 2018, is backed with match-funding by the Department for International Development. For every pound given before 31 December, the Government will donate another pound. Each operation costs about £30; so the charity's target is at least £30 million in the next three years.

Julie Jenner, a spokeswoman for the charity, said that, while sight-restoring operations such as fixing cataracts were cheap and simple, many people in the developing world found it impossible to be diagnosed, or even to reach the nearest hospital or clinic.

"Often patients live in remote areas and can't get to a health centre. Or, if they can get to see a doctor, they can't afford to pay for treatment. Some people don't even know that their sight condition is treatable."

Conditions like cataracts affect more than just those suffering from them. "Children will often miss out on school, as they stay home to help their parent or grandparent. For many, losing vision means losing their livelihood, their independence, their ability to support a family, and make a better life for themselves and their children."

To publicise the new campaign, Sightsavers filmed and broadcast a cataract operation live from Malawi, on 8 October. The story begins with an ophthalmic clinical officer, Madalitso Nyangulu, who travels on a motorbike for 40 minutes each day into rural Malawi to screen for eye conditions in far-flung villages.

On one visit, he met Winesi March, a farmer who had slowly become completely blind. Mr March, who says he is either 69 or 70 years old, was diagnosed by Mr Nyangulu as having cataracts. Both his operation and the subsequent removal of bandages were broadcast live online around the world.

In the video, viewers see Mr March's face as the doctor removes the last bandage from his eyes and he can see for the first time in several years. As he laughs in amazement, singing and dancing break out on the ward.

It is scenes like this that Sightsavers hope will inspire people to donate to their appeal.

www.millionmiracles.org. The Church Times is a media partner for the campaign.