Relationship between corneal biomechanical properties and optic nerve head changes after deep sclerectomy

Area of Science:

• Ophthalmology
• Glaucoma Research
• Corneal Biomechanics

Background:

• Primary open-angle glaucoma (POAG) management often involves reducing intraocular pressure (IOP).
• Deep sclerectomy (DS) is a surgical option for glaucoma, but its effects on corneal biomechanics and the optic nerve head (ONH) require further investigation.

Purpose of the Study:

• To evaluate changes in corneal biomechanical properties and ONH parameters after DS.
• To determine the relationship between corneal biomechanical changes and ONH alterations following DS in POAG patients.

Main Methods:

• Prospective study of 49 eyes with POAG undergoing DS.
• Assessment of corneal hysteresis (CH), corneal resistance factor (CRF), and ONH parameters (cupping, prelaminar tissue thickness, lamina cribrosa depth/thickness) using Ocular Response Analyzer and Spectralis OCT pre- and post-surgery.
• Correlation and regression analyses to identify predictors of ONH changes.

Main Results:

• Significant IOP reduction (IOPcc by 27.9%, IOPg by 30.52%) 3 months post-DS.
• Increased CH (18.4%) and decreased CRF (10.1%) observed.
• Significant reversal of ONH cupping, attributed to prelaminar tissue thickening.
• Preoperative IOP and CRF, along with postoperative IOP, CH, and CRF changes, were associated with ONH modifications.

Conclusions:

• DS significantly alters corneal biomechanics, increasing CH and decreasing CRF.
• Corneal resistance factor (CRF) is a significant preoperative predictor of ONH cupping reversal.
• Postoperative IOP reduction is the sole independent factor influencing ONH changes after DS.