Corneal Biomechanics and Visual Field Progression in Eyes with Seemingly Well-Controlled Intraocular Pressure

Area of Science:

• Ophthalmology
• Glaucoma Research
• Visual Field Analysis

Background:

• Glaucoma is a leading cause of irreversible blindness.
• Intraocular pressure (IOP) is a primary modifiable risk factor for glaucoma.
• Visual field progression indicates worsening optic nerve damage.

Purpose of the Study:

• To determine the incidence of glaucomatous visual field progression in eyes with well-controlled IOP.
• To identify risk factors associated with visual field progression in this patient group.

Main Methods:

• Prospective cohort study of 460 eyes from 334 glaucoma patients.
• Visual field progression assessed via standard automated perimetry (SAP) mean deviation (MD) slope.
• Corneal biomechanics, including corneal hysteresis (CH) and central corneal thickness (CCT), were measured.

Main Results:

• 23.5% of eyes with well-controlled IOP (<18 mmHg) showed visual field progression.
• No significant differences in mean IOP, IOP fluctuation, or peak IOP between progressing and stable eyes.
• Progressing eyes had significantly lower CH and thinner CCT.
• A lower corneal index (combining CH and CCT) increased the risk of progression by 68%.

Conclusions:

• A significant proportion of glaucoma patients with well-controlled IOP experience visual field progression.
• Corneal properties, specifically thin corneas and low corneal hysteresis, are significant risk factors.
• These findings highlight the importance of considering corneal biomechanics in glaucoma management.