Special types of contact lens not covered elsewhere in this book are described in this chapter. Lenses to Aid Diagnosis and Surgery Various special contact lenses have been developed to assist observation of the eye in diagnosing eye disease. Contact…
Introduction Contact lenses can be used for therapeutic purposes to manage a wide range of ocular conditions. When so fitted, they are referred to as therapeutic contact lenses (TCLs) or bandage lenses. TCLs are fitted mainly to protect or promote…
Introduction In this chapter, coloured contact lenses are differentiated into cosmetic lenses, i.e. tinted contact lenses that simply change the colour of the eyes, and prosthetic lenses, i.e. lenses that change the appearance of an unsightly eye, although the term…
Introduction Fitting contact lenses to children of different ages requires varying skill sets to achieve the best results for the patients. Lenses fall into two main categories: refractive and pathological. Refractive fittings are similar with all ages and, in the…
Introduction For nearly half a century, vision scientists around the world have struggled with the challenge of surgically correcting human refractive error. Typically by employing mechanical manipulation of the corneal tissue, the delicate art of refractive surgery has been greatly…
Patients who require contact lens fitting following keratoplasty (corneal graft) can be the greatest challenge to a contact lens practitioner. These patients have undergone a major surgical procedure and may be reluctant to revert to or start contact lens wear.…
Introduction Most patients with high prescriptions benefit both optically and cosmetically from contact lenses, more so than patients with low prescriptions. Fitting the lenses is not always straightforward partly due to the different lens thickness but also to the medical…
Introduction Keratoconus (KC) is a term derived from the Greek words keras (cornea) and konos (cone). It was described by Dr Benedict Duddell in 1736 and increasingly described further over the following 100 years with a variety of names including…
Introduction In 1996, Dr Tom Reim of Melbourne, Florida, had an idea that changed orthokeratology forever: He designed a lens with a small (0.60 mm) reverse curve (RC) and added a wide alignment curve to overcome the centration problems that were…
Introduction Successful contact lens fitting requires the manufacture of high-precision contact lenses and the establishment of meaningful tolerances. Such tolerances are established by national and international standards organisations. Poor-quality contact lenses can compromise wearing comfort. Contact lenses therefore have to…