1. Correlation of Visual Outcome and Patient Satisfaction with Preoperative Keratometry in Hyperopic LASIK Patients L. Espandar ; M. Moshirfar; L. B. Williams; S. B. Dave John A. Moran Eye Center, University of Utah, SLC, UT No author has any financial or proprietary interest in any materials or methods mentioned.

2. PURPOSE   To prospectively study the dependence of visual outcomes and patient satisfaction on corneal keratometry in hyperopic laser in situ keratomileusis (LASIK). Is preoperative corneal keratometry affecting visual outcome in hyperopic LASIK?

3. METHODS   Twenty-six patients (49 eyes) undergoing hyperopic LASIK. (average hyperopia +3.44 D, range +1.57 to +5.25 D).   Lamellar flap created using a Hansatome microkeratome (Bausch & Lomb Surgical, Inc., San Dimas, CA) Superiorly-hinged flaps, 160 µm thick, 9.5mm diameter.   Laser ablation was performed using a LADARVision 4000 excimer laser system (Alcon Laboratories, Inc. Ft. Worth, TX) with a 6 mm optical zone and a 9 mm transition zone.   Fourteen patients (25 eyes) with preoperative average K > 44.0 D were compared to twelve patients (24 eyes) with a preoperative average K < 43.0 D. There were no patients with K between 43.0 D and 44.0 D.   Primary outcome measures: UCVA, BSCVA, manifest refraction, postoperative dryness, patient satisfaction

4. RESULTS   Average K values plotted for each eye were significantly different between groups 1 and 2 and showed no overlap between the groups before or after LASIK. (Figure 1)   There was no difference in degree of preoperative hyperopia or any difference in keratometric change (∆K) between the groups. (Figure 2)   Refractive error was not different between the two groups preoperatively, however after LASIK correction, group 2 had a significantly higher SEQ refractive error (+1.43 D ± 0.60 in group 2 versus +0.82 D ± 0.51 in group 1, p <0.0005) (Figure 3)   Ten patients with K > 44.0 D lost 2 or more lines of best spectacle corrected visual acuity versus only one patient with K< 43.0 D. (Figure 4)   Subjective patient satisfaction (Scale 1 – 4, 4 = most satisfied) showed a significant difference between the K > 44.0 D and K < 43.0 D groups (1.52 ± 0.66 versus 2.75 ± 0.61, p < 0.0001). (Figure 5)

5. FIGURE 1

6. FIGURE 2

7. FIGURE 3

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9. FIGURE 5

10. CONCLUSIONS   Increased incidence of loss of BSCVA and decreased patient satisfaction is associated with preoperative K > 44 D in hyperopic LASIK.   One possible cause of worsened outcome is increased dry eye in the K>44 D group that was significantly drier than K<43 D group.   Another reason might be increased induction of higher- order aberration in K>44D group.   The authors recommend caution in performing LASIK on eyes with moderate to high hyperopia and steep preoperative corneal keratometry.

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