Filtering bleb functionality: a clinical, anterior segment optical coherence tomography and in vivo confocal...

Area of Science:

• Ophthalmology
• Glaucoma Surgery
• Medical Imaging

Background:

• Glaucoma surgery aims to reduce intraocular pressure (IOP) by creating filtering blebs.
• Assessing bleb functionality is crucial for determining surgical success and patient outcomes.
• Current assessment methods may lack detailed microscopic and macroscopic insights.

Purpose of the Study:

• To perform a microscopic and macroscopic analysis of filtering blebs post-glaucoma surgery.
• To evaluate the utility of in vivo confocal microscopy (IVCM) and anterior segment optical coherence tomography (AS-OCT) in assessing bleb characteristics.
• To correlate imaging findings with clinical outcomes of glaucoma surgery.

Main Methods:

• Retrospective analysis of 60 eyes from 48 glaucoma patients.
• Utilized slit-lamp examination, IVCM, and AS-OCT.
• Categorized blebs into successful (≥1/3 IOP reduction) and failed (<1/3 IOP reduction) groups.
• Examinations conducted 1-96 months postoperatively.

Main Results:

• Diffuse or cystic bleb patterns correlated with good functionality; flat or encapsulated patterns indicated poor functionality.
• IVCM showed successful blebs had more epithelial microcysts and less connective tissue compared to failed blebs.
• AS-OCT revealed lower bleb wall reflectivity in successful blebs.
• Significant correlation found between clinical patterns and AS-OCT findings, especially for cystic and diffuse patterns.

Conclusions:

• IVCM parameters strongly correlated with bleb functionality.
• AS-OCT bleb wall reflectivity was significantly related to filtering capability.
• Clinical and AS-OCT classifications showed good concordance.
• A combined clinical, microscopic, and tomographic approach enhances post-surgical bleb assessment and management.