Investigating the correlation between scleral spur angle and intraocular lens tilt
Dylan McBee1, Karim Kozhaya, Li Wang
1From the Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, Texas.
Journal of Cataract and Refractive Surgery
|January 21, 2026
Summary
The preoperative vertex-scleral spur angle (Vtx-SSA) strongly predicts horizontal intraocular lens (IOL) tilt after cataract surgery. This measurement can help estimate horizontal IOL tilt, though vertical tilt remains less predictable.
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Optical Coherence Tomography
Background:
- Intraocular lens (IOL) tilt can affect visual outcomes after cataract surgery.
- Predicting IOL tilt preoperatively is crucial for optimizing surgical planning and patient results.
- The vertex-scleral spur angle (Vtx-SSA) is a novel parameter potentially related to ocular biomechanics.
Purpose of the Study:
- To investigate the correlation between the preoperative vertex-scleral spur angle (Vtx-SSA) and postoperative horizontal intraocular lens (IOL) tilt.
- To assess the Vtx-SSA as a predictor of horizontal IOL tilt in routine cataract surgery.
Main Methods:
- Prospective case series involving patients undergoing phacoemulsification with IOL implantation.
- Swept-source optical coherence tomographers (SS-OCTs) used for Vtx-SSA and lens tilt measurements (crystalline and IOL).
- Analysis of tilt vectors (horizontal and vertical components) using Pearson correlation and linear regression.
Main Results:
- A strong correlation (r² = 0.97, P < 0.01) was observed between preoperative Vtx-SSA and horizontal IOL tilt.
- Horizontal IOL tilt constituted approximately 80% of the total tilt magnitude.
- Horizontal tilt of the crystalline lens also strongly correlated with horizontal IOL tilt (r² = 0.97, P < 0.01).
Conclusions:
- The Vtx-SSA serves as a valuable and easily interpretable presurgical predictor for horizontal IOL tilt.
- While effective for horizontal tilt, Vtx-SSA does not reliably predict minor vertical tilt contributions.
- Further research may explore methods to anticipate vertical IOL tilt more accurately.
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