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P Randall Staver

Publications and source records attributed to P Randall Staver.

4 recordsLinked to original sources

Using InterWave aberrometry to measure and improve the quality of vision in LASIK surgery.

OBJECTIVE: To compare visual outcomes in eyes undergoing aberrometry-guided (InterWave) LASIK with those in eyes undergoing standard LASIK treatment based upon refractive measures. DESIGN: Single-center, comparative, interventional, consecutive case series. PARTICIPANTS: Four hundred two consecutive eyes undergoing LASIK were analyzed retrospectively. One group, 106 eyes undergoing primary LASIK and 224 eyes undergoing LASIK enhancement, was treated with standard LASIK treatment using a 5.5-mm optical zone, 1.5-mm transition zone laser with the settings determined by manifest refraction. The second group, 44 untreated (primary) eyes and 28 previously treated (enhancement) eyes, received a multipass, multistage treatment in which the laser settings for each stage were determined by aberrometry measurements. Eyes with desired monovision (undercorrected) outcome and preoperative hyperopia were excluded from the study. INTERVENTION: An aberrometry-guided laser treatment (InterWave LASIK) was compared with the standard LASIK treatment based upon the manifest refraction. MAIN OUTCOME MEASURES: Uncorrected visual acuity (VA), manifest refraction, best spectacle-corrected VA (BSCVA), severity of halos, and root mean square (RMS) retinal blur area measured at 3 months postoperatively. RESULTS: Three months postoperatively there was no difference in uncorrected VA, BSCVA, refraction, or RMS retinal blur areas for pupil sizes of 3.5 mm between eyes treated by InterWave and those treated by standard LASIK. However, InterWave LASIK reduced the retinal blur area by 48% (P<0.0103) and 58% (P<0.0004) in primary cases and 43% (P<0.0430) and 74% (P<0.0271) in enhancement cases, respectively, for pupil sizes of 4.5 and 6.5 mm relative to standard LASIK treatments. Patients undergoing InterWave-guided treatment reported less severity of halo (0.37 vs. 0.98 [P<0.016] for primary cases and 0.35 vs. 0.73 [P<0.04] for enhancement cases). CONCLUSION: InterWave LASIK achieved acuity and refractive results equivalent to those of standard LASIK treatment based upon refraction, but resulted in superior quality mesopic vision.

Adult↗

SSR (spatially resolved refractometer): a null-seeking aberrometer.

The spatially resolved refractometer is an aberrometer used to measure the wave-front aberrations of the human eye. In its original form and the new configuration that we report, it uses the patient's perception in a psychophysical task to evaluate the wave-front errors at a variable number of loci (typically 40 or 160) across the cornea. This configuration includes pupil tracking and the ability to choose the measurement loci in software. An automated configuration that does not require patient input is also described.

Calibration↗

Wavefront aberrations from corneal ectasia after laser in situ keratomileusis demonstrated by InterWave aberrometry.

PURPOSE: To report a case of corneal ectasia after laser in situ keratomileusis (LASIK). The patient presented with minimal alterations in manifest refraction but had obvious distortions in the wavefront error of the eye, as demonstrated by InterWave aberrometry. METHODS: Retrospective case report and literature review. RESULTS: Three years following uneventful and initially successful LASIK and two subsequent enhancement procedures, a patient experienced a decrease in uncorrected and best spectacle-corrected visual acuity with only minor changes in manifest refraction and initially subtle changes on corneal topography. InterWave aberrometry showed a wavefront distortion consistent with progressive steepening of the anterior cornea, reflecting possible development of corneal ectasia. CONCLUSIONS: InterWave aberrometry in conjunction with corneal topography was useful for early recognition of the development of corneal ectasia after LASIK.

Adult↗