Correlation of Visual Outcome and Patient Satisfaction with Preoperative Keratometry in Hyperopic LA

1
Correlation of Visual Outcome and Patient
Satisfaction with Preoperative Keratometry
inHyperopic 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 gt 44.0 D were compared to twelve
  patients (24 eyes) with a preoperative average K
  lt 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 lt0.0005) (Figure 3)
• Ten patients with K gt 44.0 D lost 2 or more lines
  of best spectacle corrected visual acuity versus
  only one patient with Klt 43.0 D. (Figure 4)
• Subjective patient satisfaction (Scale 1 4, 4
  most satisfied) showed a significant difference
  between the K gt 44.0 D and K lt 43.0 D groups
  (1.52 0.66 versus 2.75 0.61, p lt 0.0001).
  (Figure 5)

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FIGURE 1
6
FIGURE 2
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FIGURE 3
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FIGURE 4
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FIGURE 5
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CONCLUSIONS

• Increased incidence of loss of BSCVA and
  decreased patient satisfaction is associated with
  preoperative K gt 44 D in hyperopic LASIK.
• One possible cause of worsened outcome is
  increased dry eye in the Kgt44 D group that was
  significantly drier than Klt43 D group.
• Another reason might be increased induction of
  higher-order aberration in Kgt44D group.
• The authors recommend caution in performing LASIK
  on eyes with moderate to high hyperopia and steep
  preoperative corneal keratometry.

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