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| RETREATMENTS | |
Dr Anand
Shroff has been an Anterior segment and corneal surgeon for almost ten
years. He has worked in great depth on the subjects of corneal diseases, keratoplasty,
and astigmatic keratotomy. With this experience combined with his expertise on
the Wavefront technology in LASIK, dissatisfied patients have often sought him
after LASIK, PRK and RK for second opinions. | |
Our WaveLight 500 Hz Concerto Laser, especially because of its unique corneal tissue saving feature,
enables us to re-treat corneas, which would have been otherwise too thin to work
upon.
Some people who have already had LASIK with earlier technologies
and experience night vision disturbances can be helped with our customized topography-guided
treatments.
Wavefront measurements of LASIK patients with such quality of
vision complaints may demonstrate a high magnitude of higher-order aberrations.
Studies demonstrate that topography or wavefront LASIK retreatments can
reduce these aberrations as well as subjectively improve these night vision and
contrast sensitivity problems. Each patient needs to be individually assessed
to make proper suggestions. | | Post-op
Refractive Surgery Complication Management: Refractive surgery complications
can be divided into those which are surgically induced and managed and those which
are healing or ablation related and typically require further laser retreatment.
Examples
of surgical complications would be: - Corneal flap striae or displacement
- Epithelial Ingrowth
- Diffuse Lamellar Keratitis
- Corneal flap irregularities:
button hole flap, free cap, short flap, thin flap
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Examples
of healing and ablation related complications are: - Topographical
abnormalities: decentrations, central islands, and peninsulas
- Spherical aberrations:
night vision problems, night glare, halos, star-bursting, ghosting
- Irregular
astigmatism: loss of best corrected spectacle vision
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is of course considerable cross-over as many surgically induced complications
produce loss of contrast sensitivity, loss of best corrected vision and severe
disturbances in night vision. While we have been managing surgical complications
for several years, the development of wavefront technology has allowed us to finally
fully evaluate all these patients and present possible treatment options for them.
In about 70% of cases, we are now able to provide topographically guided solutions
for patients. It is impossible however to predict which patients will be the most
suitable candidates with the best chance of success until completing the diagnostic
wavefront and topographical testing. The WaveLight 500 Hz Concerto Laser
has been our excimer laser system of choice as the Tscherning wavefront analysis
system has provided us with reproducible detailed data in the majority of cases
for surgical planning. The laser system also possesses specific features ideal
for both the new patient and the post-refractive surgery patient for higher quality
visual results:
- Laser spot size < 0.90 mm [0.63 mm half max.]
- Repetition rate 500 Hz
- True Effective Optical Zones upto 7 mm
- Infrared Eye-tracker
with 2.5 msec response time and automatic centration
- Prolate cornea ( aspheric
treatment patterns for classic and wavefront applications)
The small laser spot size is mandatory to produce fine complex
treatment patterns. The rapid repetition rate is vital to maintain
corneal hydration intra-operatively, especially in wavefront
guided procedures with larger optical zones where a prolonged
treatment time could adversely affect the planned treatment
profile. A simple principle in laser refractive surgery is to
keep the eye as physiologically hydrated as possible intra-operatively
for a faster visual recovery with less risk of swelling and
epithelial ingrowth. In cases of patients with night glare,
the ability to create a prolate 7 mm true effective optical
zone with a 9mm blend zone is highly beneficial. Lastly, the
eye-tracking response time must be short enough to adequately
account for saccadic eye movement. The Wavelight Concerto response
time is better than any other excimer laser system without the
need to dilate the pupil, which allows the patient to fixate
on the target light more easily with a faster visual recovery.
For topography-linked retreatments, the WaveLight 500 Hz Concerto Laser has the best
capabilities at present. It should be understood however that the diagnostic analysis
is what determines the final treatment method of choice recommended to any individual
patient.
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