Cataracts: The Most Common Affliction Reducing Sight
Vision is so important to us all and so easy to take for granted until something goes wrong. There are many diseases that can upset our visual system and our vision.
A cataract is the common one and fortunately, is eminently treatable, and with very little risk. The modern techniques are spectacularly good and provide such good fixes for the ageing eye that function returns to almost as what it was as in youth. The 20th Century saw remarkable advances in cataract treatment – Sir Harold Ridley in the 1940s (knighted for his advance in this field) introduced the concept of an intraocular lens. This stemmed from the identification of the fact that fighter pilots from the 2nd World War, who suffered penetrating eye injuries from the Perspex of the fighter aircraft canopies, had no intra-ocular reaction to the material. This culminated in the first intraocular lens inserted into an eye on 29th November 1949. A momentous day!
The art of cataract surgery has moved through the techniques of removing the whole lens of the eye, still through large incisions with instruments that froze to the lens (driven by the gaseous expansion of freon and carbon dioxide in an instrument called a “cryophake”, facilitating the cataract removal procedure called intra-capsular cataract surgery). This matured into a procedure called extracapsular cataract extraction, in which only the opaque contents of the cataract are removed by expression and suction through smaller incisions.
The demand for reduction in incision size continued, refining the extracapsular surgical process until the invention by Dr Charles Kelman in 1967 of the phaco-emulsifier which allowed dissolution of the cataract by ultrasound and the removal of the lens by suction only through a very small incision of approximately 3.5mm. The refinements of today of this technique allow the cataract to be removed through a 1-2mm incision.
Lens technology then had to catch up to the micro-incisional removal techniques and with the new materials and guides now available, the same 2mm incisions can be used to introduce the lenses into the eye. The 2mm incisions virtually did not disturb the important refracting structural arrangements of the eye – a major step forwards.
In fact, this micro-incisional cataract surgery status quo has been taken advantage of by new glaucoma treatments which can use these micro-incisions at the time of cataract surgery for the insertion of nano-devices into the eye that lower eye pressure (iStent), correcting 2 problems at the same time – glaucoma and cataract! How exciting and clever are these new developments! Makes us ask what the next development will be and when!
Dr Frank Howes is an ophthalmologist who specializes in laser vision correction, cataract surgery and refractive surgery at the Eye and Laser Centre Gold Coast.