Advanced Cataract Surgery

Cataract is a cloudiness that sets in the natural lens in our eye usually as a result of ageing. Upon removal of this cloudy lens (cataract) and artificial replacement (intraocular lens, IOL) has to be made. Advances in ultrasonic phacoemulsification, fluidics and IOL design have resulted in excellent outcomes for patients undergoing cataract surgery. Cataracts in patients with diabetic eye disease or other retinal vascular disease calls for a higher refinement in technique owing to their higher risk-profile in order to minimise complications and achieve superior results compared to standard care that is acceptable for low-risk patients. Accurate pre-operative planning aided by the use of cutting-edge therapeutics is another key to highly successful end results.

Laser Cataract Surgery

Cataract surgery is performed using ultrasound energy. The procedure is called phacoemulsification (phacos=lens). Laser emulsification instead of ultrasonic emulsification was developed but was found to be inferior and the range of severity of the cataracts that could be treated was quite limited. For these reasons it never really took off. Instead research was focussed on making ultrasonic phacoemulsification efficient, responsive and safer which has proved to be a success. However laser cannot be fully written off as it is re-emerging in the form of Femtosecond laser technology which helps perform certain steps of the operation.

What difference Does an IOL Make?

Intraocular lenses (IOLs) made of either silicone, acrylic or polymethyl-methacrylate are substituted following removal of the natural focussing mechanism of the eye, the crystalline lens that had become cataractous (cloudy). IOL models have universally upgraded their design to aspheric optics, advanced square-edged design and incorporate UV protection the major factors shown on recent research to improve their performance. My choice of IOL is the KS3-Ai lens(STAAR Surgical AG, Switzerland) developed by Canon-Staar, which is a pre-loaded silicone lens that offers superior contrast sensitivity even in low light conditions claiming to match that of a 20 year old. Its Polyimide haptics (the hinges that hold the lens in position) is a new biomaterial that offers excellent stability when implanted inside the eye.

Presbyopic lenses and astigmatic lenses are other types of lenses which are evolving rapidly. Initial results with these lenses were disappointing and in my professional opinion have still got a way to go before we see the predictable results that we see with lenses like the KS3-Ai. Latest research into modifying the IOL power following surgery is showing greater promise and may be available for use in the near future (see the section on Future of cataract surgery).

Future of Cataract Surgery

Cataract surgery is one area where there is an abundance of high quality research leading to the emergence of enhanced technology. In my view there are two areas which are showing the most promise. They both involve the use of Femtosecond laser technology. Femtosecond lasers have been in use in corneal surgery to create customised, high precision incisions. The technology is now being adapted to carry out some steps of cataract surgery. Although it cannot replace ultrasound technology to emulsify the cataract, using both modalities would raise the accuracy of the surgery.

Index shaping is yet another marvel of Femtosecond laser whereby the focussing power of the IOL can be modified following surgery. In a simple procedure where the treatment time is expected to last about 20 seconds, it would be possible to fine-tune the IOL’s power to suit the patients focusing needs.

External Resources

The Royal College of Ophthalmologists (RCOphth)

The RCOphth is a professional and academic body for Ophthalmologists practising in the UK that awards ophthalmic qualifications, sets professional standards and promotes research. Their resources on cataract surgery are of very high standard and adopted for use widely to provide patient information and guide them to making an informed choice for cataract surgery.
http://www.rcophth.ac.uk/page.asp?section=369&sectionTitle=Speci…

Drivers and Vehicle licensing authority (DVLA)

This webpage of the DVLA details information for patients who have cataracts on its impact on their ability to drive safely.
http://www.direct.gov.uk/en/Motoring/DriverLicensing…