Ans. Dr. Anand Shroff, Chief Surgeon, at the Shroff Eye Hospital, Bandra, Mumbai, has several years of experience in LASIK and is among the country’s longest-standing users of the benchmark ‘flying-spot’ laser technology. He also is the first to use the WaveLight Allegretto 200 Hz excimer laser in India before the most recent Concerto 500 Hz was launched at our Eye Hospital.
Wavefront LASIK or custom LASIK is the most advanced LASIK method today. It can be performed using various lasers. The speed of the laser and its applications are very important in delivering results. Today, we use the world’s fastest laser the 500 HZ whereas most other lasers are close to 50-100 Hz and some to 200-250-400 Hz.
Wavefront technology has been around since 1998. It is specifically for those patients who would end up unhappy if a standard LASIK procedure is done on them. These patients are detected during their LASIK screening and evaluation, by certain specific indications which would arise on the topography and aberrometry tests. It is also a technology for those who have undergone LASIK on poor obsolete lasers or have undergone PRK or RK [other techniques for removal of spectacle numbers] and are having problems.
We believe in the best, having always stood for distinction in eye care.
After working on different lasers and being offered other lasers still entering the market, we went ahead with the Wavelight Concerto 500 Hz laser because of its superior technology. Most lasers are retrofitted for wavefront or to simply put upgraded whilst this laser has been developed for wavefront from scratch. The detailed research in the laser system took into account the needs of the surgeon, patient as well as looked after the many drawbacks of the other laser systems.
To put it simply, the ‘ wavefront’ is the way the natural light pathway goes in the eye thru the entire optics. This is supposed to be a smooth path in an ideal eye. As the light travels thru the other optical system inside the eye, like the lens, vitreous jelly etc. it undergoes further degradation. This is acceptable to a certain extent and that is why the eye surgeons have reached a 6/6 or 20/20 criteria as normal sight. However, when these errors or ‘higher order aberrations’ as they are known, exist to an extent in which they need to be treated then wavefront treatments [Custom LASIK] are a must for such patients.
Earlier lasers without wavefront technology can only correct the spectacle number, which arises from the curvature irregularities of the cornea. Our laser can treat the entire optical system errors. Further, when we treat these optical errors by doing wavefront, some patients actually gain lines of sight, better than 6/6 OR 20/20.
Then again, that is not our aim alone. We want to give quality of sight. By which I mean good contrast sensitivity and good night vision. In the night the pupil expands or dilates to let in more light for visibility. If a laser treats a zone, which is smaller in diameter than the diameter of expansion of the pupil, then what you have is an untreated rim of cornea, which in the night is going to disperse light in various directions resulting in haloes or glares of light. This is the problem most of the West ie. USA is facing, because most of their lasers treat a 5 mm zone only and because of lighter colored eyes, their pupils [in US] can dilate upto 7 mm. Our laser can treat wide pupils and has a near zero percent of night vision problems in our experience.
There is a lot more of this laser, which helps the patient and the doctor. We can now treat higher numbers with more accuracy, re- treat earlier laser unhappy patients to get better night vision etc. and include patients who would have been poor candidates for earlier technology. This is why our success rates have been good from the beginning, as we have been thorough in our patient evaluation and stringent in our eligibility criteria.