Volume I Issue 13

Originally published, April 1, 2001

LASIK after Dark: How to reduce glare

Glare is an important consideration for LASIK patients and LASIK surgeons. Early complaints of halos or difficulty with night driving have inspired refinements in laser technique. Measurement of pupil diameter in a dark room is now part of the standard LASIK evaluation.

An ideal ablation zone is larger than the diameter of the pupil. This reduces the chance of glare and halos.

Producing an ablative zone (lasered area) larger than the pupil diameter should reduce these symptoms. All light rays enter the eye focused, so no halos are produced. Initially, excimer lasers could only produce ablative zones between 4.5 and 6.0 millimeters. Because most pupils dilate from 5 to 9 millimeters in darkness, it is not surprising early laser vision correction patients experienced glare.
Virtually all popular excimer laser manufacturers have upgraded their systems. Patients with large pupils still represent a challenge to the LASIK surgeon. “You can’t simply continue to increase the size of the ablative zone. You will sacrifice too much corneal tissue and risk ectasia [weakening and bulging of the cornea],” explained Dr. Lewis.
Jose Barraquer, MD, of Bogota Columbia, the grandfather of LASIK suggested that 250 microns of untreated cornea remain after surgery. Ultrasonic pachymetry measures each patient’s corneal thickness prior to surgery. Measurements range from 420 microns to 600 microns.
“We routinely calculate the residual cornea before any LASIK procedure. Enhancements are no exception. We must temper our desire to minimize glare with our need to leave the patient with a strong and healthy cornea,” Lewis continued.
LASIK surgeons today divide the ablative zone into an inner optical zone and a surrounding transition zone. The optical zone corrects the patient’s vision. The transition zone removes less tissue and smooths the area between the optical zone and the untouched peripheral cornea.
Lewis claims, “One of the truly wonderful advantages of our Nidek laser is its ability to tailor the optical zone and the transition zone for each patient. I can consider pupil size, refractive error, and corneal thickness and select the ideal ablation pattern.”
Another advantage of separate optic and transition zones is the reduction of regression. The corneal contour is gently curved. The body tolerates this shape and exhibits little or no tissue response. Enhancement rates are significantly reduced.
Laser manufacturers have helped by improving their alignment and aiming systems. The attached surgical microscope helps the doctor position the laser.
“The fiber optic light source and the fixation capabilities of our system make me confident. I know the laser energy will go exactly where it should,” commented Lewis.
Medicine and industry continue to improve LASIK. 20/20 acuity is no longer the gold standard. Patients want excellent vision in all lighting conditions.

Happy Faces

Karen and David Thompson relax for a photo during one of their post-operative LASIK visits.

Volume I Issue 12

Originally published, March 25, 2001

“Best of Philly” has LASIK

This year’s winner of Philadelphia Magazine’s “Best of Philly Teahouse”, Grace Chen of Ray’s Cafe has successful LASIK surgery by Dr. James Lewis.

PHILADELPHIA, PENNSYLVANIA _ When Dr. Lewis lived in Center City he was a frequent patron of Ray’s Cafe. Many considered it the best cafe in the city.
In the last decade Philadelphia Magazine recognized Grace Chen (owner of Ray’s Cafe) four times as the “Best of Philly Coffee”. She won again this year for her selection of exotic and vintage tea.
“I was honored when Grace asked me to perform her LASIK surgery”, Lewis explained. “Her extended work schedule did not make her the ideal contact lens patient.
During her evaluation Dr. Lewis found that Ms. Chen had 14 diopters of nearsightedness. This is three to four times the amount present in most LASIK patients.
“There is a limit to what excimer laser refractive surgery can accomplish safely. I decided to operate conservatively and preserve her corneal health”, Lewis continued. “We both knew an enhancement could be used to refine the results.”
Enhancement surgery is nothing more than additional laser energy applied to the patient’s cornea to optimize visual acuity. Patients with high degrees of nearsightedness and astigmatism are more likely to need this fine-tuning.
“LASIK surgeons are foolish to boast of their low enhancement rates. They either don’t care what their patients need or they don’t know how to take advantage of this excellent tool”, Lewis commented.
Grace Chen needed an enhancement. While her glasses shrunk from 14 to 2 diopters she still couldn’t drive safely without them. Her enhancement surgery took a few minutes. She was back at the Ray’s Cafe with 20/20 vision the next morning.
“I am now learning the subtleties of Oolong and Green Tea. This is one of the great perks of this job”, Lewis said.
Despite the accuracy of laser vision correction, patients heal differently. Patients requiring an enhancement are not surgical failures. They are individuals who can achieve outstanding results with skilled application of this highly sophisticated technology.

Gourmet Coffee and Tea Aficionado refers world-class Fine French Pastry Chef for LASIK Surgery

Pascal Adelmar, Chef and Founder of Au Fin Palais winner of “Best of Philly Pastry” is on our LASIK schedule.

Mr. Chen oversees the incredible assortment of Fine French Pastries at Au Fin Palais following its recent alliance with Ray’s cafe.