Pilot study on erbium laser phacoemulsification.

PURPOSE To investigate the suitability of erbium laser phacoemulsification for cataract surgery using a prospective pilot study. DESIGN Prospective, single-center, nonrandomized clinical trial. PATIENTS AND METHODS Slit-lamp microscopy, keratometry, best-corrected visual acuity, refraction, pachymetric corneal thickness, endothelial cell density, and intraocular pressure were assessed before surgery and on the first, fourth, fourteenth, and the sixtieth day after surgery in 40 eyes of 34 patients with senile cataract (17 males with a mean age of 67.3 years; 17 females with a mean age of 73.2 years). All operations were performed by one surgeon (HH) using the MCL-29 erbium laser (Aesculap-Meditec, Jena, Germany). The nuclear sclerosis grade ranged from 0 to 4. MAIN OUTCOME MEASURES Primary outcome measures were defined as the ability to emulsify the lens nucleus under clinical conditions and the occurrence of side effects. Secondary outcome measures included the change in visual acuity, refraction, intraocular pressure, corneal thickness, and endothelial cell density. RESULTS Complete emulsification of the lens nucleus using the erbium laser was achieved in 36 of 40 eyes (90%; nuclear sclerosis grade, 0-3). Partial emulsification of the nucleus was possible in two cases with grade 3 nuclear sclerosis, in one case of grade 2 nuclear sclerosis, and in one case of cataract with grade 4 nuclear sclerosis. Mean phacoemulsification time was 3 minutes, and the total applied energy equaled 38.5 J. The postoperative changes in visual acuity, spherical and astigmatic refraction, and intraocular pressure were found to be the same as with ultrasonic phacoemulsification. The decrease in the density of endothelial cells (by 0.96%) was not statistically significant. Posterior capsule ruptures occurred in three eyes early in the series. There were no further vision-threatening complications. CONCLUSIONS Erbium laser phacoemulsification is effective for lenses with mild to moderate nuclear sclerosis. For higher grades of nuclear sclerosis, further improvements in technical and surgery-related parameters are required.

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