J Refract Surg. 2006 Jan-Feb;22(1):48-53. Hiatt JA, Grant CN, Wachler BS.
Boxer Wachler Vision Institute, 465 N Roxbury Dr, Ste 902, Beverly Hills, CA 90210, USA.
PURPOSE: To report the results of complex wavefront-guided LASIK retreatments.
METHODS: Twenty eyes (15 patients) with histories of conventional LASIK surgery and significant visual complaints of glare and halos due to higher order aberrations were treated. Wavefront-guided retreatments were performed with the LADARVision CustomCornea system (Alcon, Ft Worth, Tex). Pre- and postoperative topographies, wavefront measurements, and subjective reports were analyzed.
RESULTS: Postoperatively, patients had an expanded optical zone, many with improved centration. Lower and higher order aberrations decreased following wavefront-guided ablation. Mean higher order root-mean-square decreased from 1.01 +/- 0.25 microm preoperatively to 0.84 +/- 0.23 microm postoperatively. Mean coma decreased from 0.59 +/- 0.26 microm to 0.43 +/- 0.21 microm. Mean spherical aberration decreased from 0.66 +/- 0.25 microm to 0.54 +/- 0.27 microm. Subjective reports of glare and halo symptoms improved in all patients.
CONCLUSIONS: CustomCornea wavefront-guided treatments are effective in reducing lower and higher order aberrations, expanding optical zones, and improving subjective reports of adverse aberration sequelae such as glare and halos.
NOTE: The abstract doesn't say how much tissue was ablated during the retreatment, and how much tissue remained under the flap. There is debate regarding how much needs to remain under the flap to prevent ectasia. Also, if you look at the decrease in HOA RMS, the numbers are relatively small, and it doesn't say at what diameter the scan was taken. (Taking a 6 mm scan on a patient with 8 mm pupils is like weighing a 250 lb. woman on a scale that only goes up to 175 lbs.) So the patients' subjective reports of "glare" and halos improved, but at what risk? Ectasia? Epithelial ingrowth? Flap complications? DLK? How much did it really improve? A small improvement would be great, but not at the long-term increased risk of ectasia (opinion). One more thought, if pupil size doesn't matter, why did the expansion of the optical zone reduce the reports of "glare" and halo?