Refractive outcomes after cataract surgery: Scheimpflug keratometry versus standard automated keratometry in virgin corneas.

PURPOSE

To compare pupil size-based Scheimpflug Holladay equivalent keratometry with conventional automated keratometry in refractive outcomes after cataract surgery in patients with virgin corneas.

SETTING

Private practice, Lombard, Illinois, USA.

DESIGN

Comparative case series.

METHODS

Two groups had phacoemulsification with implantation of a posterior chamber intraocular lens (IOL). Both had immersion ultrasound biometry. The study group had Scheimpflug keratometry based on pupil size. The control group had conventional automated keratometry. The IOL power was calculated with the Holladay 2 formula. Statistical analysis of the refractive outcomes and the keratometry (K) readings was performed.

RESULTS

The study group comprised 76 patients (110 eyes) and the control group, 94 patients (137 eyes). The mean average K reading was 43.45 diopters (D) in the study group and 43.51 D in the control group; the difference was not statistically significant (P=.779). The mean absolute refractive error was 0.480 D in the study group and 0.252 D in the control group; the difference was statistically significant (P<.001). In the study group, 77 eyes were within ± 0.50 D of the intended postoperative refraction, 28 were between ± 0.50 D and ± 1.00 D, 4 were between ± 1.00 D and ± 1.50 D, and 1 was between ± 1.50 D and ± 2.00 D. In the control group, 131 eyes were within ± 0.50 D, 3 were between ± 0.50 D and ± 1.00 D, and 3 were between ± 1.00 D and ± 1.50 D. The between-group difference was statistically significant (P<.001).

CONCLUSION

Conventional automated keratometry gave better refractive outcomes after cataract surgery than pupil-based Scheimpflug keratometry.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.