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Updated: Mar 27, 2026
Using an Automated Hirschberg Test App to Evaluate Ocular Alignment
Published on: March 24, 2020
Comparative accuracy of image-guided systems and smartphone applications for enhanced monofocal toric IOL alignment
Soonwon Yang1, Ji-Yun Song2, Youngseo Jeon2
1Department of Ophthalmology, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
Purpose:
To compare the clinical outcomes of cataract surgery with toric intraocular lenses (IOLs) using two different alignment methods: an image-guided system and a smartphone application-guided method, and to evaluate their efficacy, feasibility, and potential for improving accessibility.
Methods:
This retrospective study analyzed 171 eyes of 120 patients undergoing cataract surgery with an enhanced monofocal toric IOL (Eyhance, Johnson & Johnson Inc., USA). Because some patients contributed both eyes, within-patient correlation was accounted for using generalized estimating equations (GEE). Outcomes included toric alignment error and refractive outcomes.
Results:
Mean absolute alignment error was 1.37 ± 1.29° in the image-guided group and 1.84 ± 1.47° in the smartphone-guided group. In clustered GEE analysis, the smartphone workflow was associated with higher absolute alignment error (p = 0.04). Postoperative refractive cylinder and spherical equivalent prediction accuracy were similar between groups.
Conclusion:
Both systems demonstrated excellent refractive outcomes. The image-guided system provides superior accuracy in total absolute alignment error. While the smartphone application also provides comparable outcomes, it offers a cost-effective alternative, expanding accessibility in resource-limited settings.
