|Year : 1989 | Volume
| Issue : 2 | Page : 58
History, developments and future thoughts of intraocular lens
Prabha Eye Clinic & Research Centre, 504, 40th Cross, 8th Block, Jays Nagar, Bangalore - 560 070, India
K R Murthy
Prabha Eye Clinic & Research Centre, 504, 40th Cross, 8th Block, Jays Nagar, Bangalore - 560 070
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Murthy K R. History, developments and future thoughts of intraocular lens. Indian J Ophthalmol 1989;37:58
References to the possibility of introduction of a corrective lens inside the eye are met with in the history of ophthalmology as early as 1776. However this became acceptable to the ophthalmic community only after Dr. Ridley's momentus performance of the surgical procedure in the year 1949. The observation and findings of Dr. Ridley were welcomed with caution and as of any other discovery it passed through two decades of restricted approval and acceptance to be followed by nearly universal acceptance in the last two decades.
The first twenty years, following the discovery of Intraocular lens and its introduction into the posterior chamber, were mainly devoted to the development of a reduced weight intraocular lens with a high quality finish. It was also the period when the alternate location for the seating of the lens namely the anterior chamber and pupillary area were explored. The extensive practice of intracapsular cataract extraction and the possibility of dislocation of the intraocular lens into the vitreous cavity appear to have mainly governed and influenced this search for alternate location. Many giants of British and European ophthalmology find a place in this exciting and difficult period of development. The development of microsurgical techniques and better and greater understanding of the corneal physiology and mechanism of glaucoma were the pointers which guided the further course of developments.
The significant complication of endothelial decompesation which was seen with the pupillary lens and to a lesser extent with the anterior chamber lens and the secondary glaucoma which was met with in many designs of angle supported lenses led to a review of the situation and hastened the return to the posterior chamber lens. This also led to the resurgence of the microsurgical planned extracapsular cataract extraction. The discovery of flexible posterior chamber lens which could be universally employed made a notable impact and many further developments have been the modifications of this lens design. These advancements were concentrated on the alteration in the flexibility, angulation of the haptics and diameter of the optic. In addition to this, coating of the lens with Ultra Violet abosrbing material and heparin have also been studied. There has also been a general tendency to shift to lenses where the optics and haptics are made of the same material (single PMMA lens).
Although the posterior chamber location of the intraocular lens in universally accepted further refinements and understanding of whether the lens should always be situated in the capsular bag is being debated and a gradual shift to in the bag insertion is taking place.
Along with the changes in the intraocular lens, the discovery of sodium hyaluronate as a space maintaining and cushioning agent to protect the corneal endothelium has influenced and increased not only the safety of the cataract surgery, but also has opened the new field of viscosurgery.
Another significant discovery has been that of the Neodymium Yag laser, the answer to the posterior capsule opacification which was the main drawback of extracapsular cataract extraction.
Attempts to develop lenses with newer materials like silicone and Hexamethyl Methoacrylate have been attempted in order to increase the flexibility of the lens so that it can be inserted inside the eye through a small incision. Such research has received considerable encouragement from the Phako-fragmentation techniques of cataract extraction.
While the position of the intraocular lens seems to be relatively safe at the moment, the fact that these lenses cannot alter their focus has ushered in the development of bifocal and multifocal (difraction) lenses. While this is a welcome step, long term observation is necessary before its universal acceptance.
The future may see better and improved varities of multifocal lenses. One can envisage the possibility of achieving a lens which could be made to alter shape and/or position to provide accommodative ability to the eye. The future years will also see the extensive employment of this procedure in the developing countries and it may even be employed in the eye camps.
The future years may also place the position of intraocular lens in the treatment of congenital cataract in a better mileu of understanding. One should also expect an increased numbers of corneal and glaucoma problems as a complicating factors of intraocular lens insertions in future years.