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*EC-5000 Product Info

*Event: EC-5000 Excimer Laser Training and Certification Course

*News Release: Nidek Responds to Patent infringement Allegations by VISX

*News Release: Nidek wins another round in excimer laser patent litigation

*News Release: Nidek defends itself against VISX

*News Release: Nidek Excimer Laser Receives FDA Approval



(Fall, 1998)

Nidek LASIK Clinical Study for Correction of Low to High Myopia, Astigmatism Offers Promising Preliminary Results

Clinical Study Corrections Range From -1.13 to -17.13D

Important Note: The Nidek Excimer Laser EC-5000 is not approved for sale in several countries yet. For more information please contact Nidek.
(Caution for the United States only.)
CAUTION - Investigational Device. For PARK, LASIK, PTK, or any use other than PRK, is limited by United States Law to investigational use.

Preliminary results of Nidek's LASIK clinical study are presented here, featuring data for correction of myopia and myopia with astigmatism. Phase III of the study is being carried out at eight U.S. investigational sites. Subjects may undergo photorefractive intrastromal keratectomy under a keratomileusis flap to correct myopia ranging from -1.0 to -20.0D, and up to 4.0D of astigmatism. Average correction of eyes in this preliminary report is -5.89 diopters. The Chiron ACS microkeratome was used in most cases, followed by a 5.5mm optical zone ablation, and a transition zone of 7.0mm diameter with the Nidek EC-5000 excimer laser. Refractive outcomes have been promising, with results exceeding FDA guidelines for low myopes, even though the treatment range far exceeds the low myopia category. At six months, 82% of all eyes are within +/- 1.00D of the target postoperative refraction.

Uncorrected visual acuity (UCVA) at six month postoperatively was 20/20 for 67% for all eyes and 20/40 for 88% of all eyes. Additionally, more than 20% of eyes achieved UCVA levels which were better than their preoperative, best-corrected visual acuity. Less than 1% of eyes demonstrate a loss of best corrected visual acuity of 2 or more lines four weeks or later following surgery.

The Nidek EC-5000 excimer laser features a scanning beam delivery system designed to produce exceptionally smooth surfaces. A modified nomogram utilizing software for surface ablation (PARK) as a base was developed during the preliminary study, and all cases were performed at 40HZ laser pulse rate (equivalent to four scans per second). Adjustments to the treatment nomogram are being made for the latter part of the study, and are expected to improve accuracy and further reduce the number of over- or under-corrected cases.

For more information, please contact Nidek Technologies Inc. at
   Phone: +1-626-578-1351 or
   Fax: +1-626-578-1327.

Uncorrected Visual Acuity at six months (median) postoperative examination:  Visual Acuity Percentage

20/20 or Better: 67.0%
20/40 or Better: 88.0%

Refractive Result Accuracy (Spherical Equivalent at Six Months):  Deviation from Intended Correction Percentage

+/- 0.5 D 66.0%
+/- 1.0 D 82.0%
+/- 2.0 D 98.0%

LASIK Complications:  Epithelium in Interface: <1.0%
Incomplete or Too Thin Flap: <1.0%
Infection / Infiltrates: <1.0%
Required Repositioning of Flap: <1.0%


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