Cataracts develop in the lens of the eye, which is situated behind the pupil. The clear central window becomes cloudy and opaque. They are associated with ageing and also with a number of diseases, such as diabetes, and with prolonged use of steroids.
Surgical treatment is required but it can now be carried out under local anaesthetic for most people, so an overnight hospital stay is not necessary.
The diseased lens is removed and a plastic lens put in its place. The cost of a single cataract operation is about £1,500 or £800 sterling.
In the Republic:
Bridget is an 87-year-old widow who lives alone in west Donegal. Her family works in Scotland but she is well supported by neighbours and friends.
In December 1997 Bridget noticed progressive loss of vision in her right eye. She had already had cataract surgery in her left eye three years previously, so she went to her GP suspecting a similar problem in the right eye.
Her GP noted a mature cataract and referred Bridget to an eye specialist who saw her in May 1998. The specialist decided she did not need surgery at that time, but Bridget's condition deteriorated to the point where her ability to live independently was being compromised.
Her GP kept telephoning the hospital in Sligo to secure an appointment for an operation. Eventually, in June 1999, she had a cataract operation under local anaesthetic.
She recovered well from the operation and continues to live alone with the support of a home help.
Bridget's GP describes a typical waiting time of one year to see an ophthalmologist in outpatients. There is usually a further wait of six months to a year before a surgical appointment is available.
However, the North-Western Health Board does have an arrangement with the North-West Independent Clinic in Bally kelly, Co Derry.
Urgent cataract operations will be performed under contract in this private hospital, usually within two weeks of being assessed, with all costs paid by the health board.
The North-Western Health Board is hopeful that with two eye surgeons in Sligo and an imminent appointment in Letter kenny, waiting lists for eye surgery in the region will continue to decrease.
In Northern Ireland:
Douglas is a 77-year-old retired civil servant living in east Belfast. He is married and lives with his wife. He has heart disease and late-onset asthma, but remains active.
On a routine visit to his optician he was told he was developing cataracts in both eyes. His GP referred him to the nearest ophthalmic surgeon.
He was seen four months later in the outpatients' department and told he would need surgery, but no date was available.
A few months later, his vision was noticeably reduced, to the point where he could not read the paper or watch television. He was also beginning to stumble and fell on one occasion when he missed a step while out shopping.
Douglas's GP became more concerned but there was still no date for cataract surgery. He sought treatment for his patient at Belfast's Mater Hospital where Douglas was seen in weeks and surgery was provided within three months.
Douglas went into hospital in the morning, had his cataracts removed under local anaesthetic and was driven home by his wife that afternoon.
He was especially impressed when telephoned at home by the surgeon in the evening to check that he had recovered.
The Comparison:
A major difference between North and South is that GPs can "purchase" services such as surgery from different service providers.
As can be seen from Douglas's experience, this can radically change the waiting time associated with certain procedures.
The use of the private hospital in Derry by the North-Western Health Board as a "valve" for urgent cataract surgery is an approach that could be extended to the routine management of waiting lists.
Most health boards have private hospital facilities within their boundaries with which they could enter into contractual arrangements for a range of medical interventions.
Next week: the wait for hernia operations