Quantification of Ocular Biomechanics In Ocular Manifestations of Systemic Autoimmune Diseases

ABSTRACT

Purpose: To quantify biomechanical change associated with autoimmune diseases using Corvis ST deformation data.

Methods: Cross-sectional, observational, case control study of 76 patients with systemic autoimmune disease and 21 control subjects. All patients underwent detailed ophthalmic examination with Corvis-ST (Oculus Optikgerate Gmbh, Germany) measurements for biomechanical properties of the eye.

Corneal deformation and also deformation caused by the extracorneal tissue were recorded. Using a mathematical formula, the three parameters, namely, corneal stiffness (kc), extracorneal tissue stiffness (kg), and extracorneal tissue viscosity (μg), were defined.

Results: The biomechanical analysis showed that kc and μg were significantly lower in patients with systemic autoimmune disease with eye manifestations than control group. However statistically, it was significant in rheumatoid arthritis (RA) patients only.

Conclusion: The new parameters, namely, kc, kg, and μg, can provide a sensitive marker of the ocular activity of the collagen vascular diseases.

Keywords:

• Ankylosing spondylitis
• corneal stiffness
• corvis-ST
• extracorneal stiffness
• granulomatosis with polyangitis
• ocular biomechanics
• rheumatoid arthritis
• sarcoidosis
• systemic autoimmune diseases
• systemic lupus erythematosus

Acknowledgments

We would like to acknowledge Mr Darshan, Mrs Roopa Prakash, and Mrs Rajeswari for helping us to get the work up done for our patients. HLA B27 uveitis is associated mostly withThis study was supported in part by the SIBAC grant from the Indo-German Science and Technology center, Government of India.

DECLARATION of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.