A scleral lens is one that sits on the sclera - the white of the eye in humans - and the advances made in the technology associated with contact lens manufacture and design, as well as scientific know-how, have brought relief to many people who need their vision correcting.
contactlenses.co.uk recently charted the timeline of the modern contact lens, from its invention in the 1880s right through to the present day.
It said a look back over the history of this now common-place item reveals how quickly the technology adapted for them to become a part of everyday life fro so many.
"The the corneal lens in 1947; the soft lens by [Otto] Wichterle in 1961; the fully-fledged, mass-produced, disposable lens by Johnson and Johnson (J&J) Vision Care in 1988; and the first silicone hydrogels in 1999," the article summarised.
"Of these events, the arrival of disposable lenses has almost certainly had the greatest effect on practitioners, the public and contact lens manufacturing."
The first contact lenses were made from very thin glass. Professor Wichterle himself quickly realised that what was really required was a disposable lens that could be mass-marketed cheaply.
This concept was taken on board by J&J and their efforts to produce such a lens was backed by the US Food and Drug Administration but the true meaning of disposable - that lenses should not be reused but thrown away after each use - was only realised in 1988.
It was in this year that J&J launched Acuvue onto the UK market, the birth of a now famous brand. The company structured price tiers and two types of disposables as well as pumping investment into its ongoing educational programmes.
"In fact J&J has always employed key professional personnel to assist practitioners, maintain their ongoing educational programmes and promote research and development," Optician Online reported.
"This culminated in 2006 with the opening of its first Vision Care Institute in Europe."
The success of the new disposables was enabled by a new technology, a polymer called etafilcom A, which was developed by an American company, Frontier Contact Lenses, which was eventually bought by J&J.
Three-monthly disposable contact lenses have also become popular and other companies such as Bausch and Lomb have become big players in the contact lens arena.
Following this breakthrough, J&J has also introduced ultraviolet radiation protection into its lenses as standard by 1997, according to the article. Other developments include Acuvue coloured lenses and enhancers - the contact lens has moved from a simple vision corrector to a fashion accessory.
In addition, toric lenses for astigmatisms were introduced by Ciba Vision and Wesley-Jessen and silicon hydrogels started to be included in contact lens manufacture to provide contact lenses for extended wear.
By 2007, daily disposables accounted for 40 per cent of new contact lenses fitted in the UK, Optician Online says.
This could because they are convenient, good for people who like sports suitable for children and some experts suggest that disposables cut down on eye infections, as long as wearers employ adequate hygiene when putting them in and removing them.
Contact lenses are cheaper when bought online rather than on the high street and have the additional convenience of being delivered. Customers can also save even more money on them by buying them in bulk.
by Emily Tait