Visualization of Scleral Flap Patency in Glaucoma Filtering Blebs Using OCT.

Area of Science:

• Ophthalmology
• Medical Imaging
• Glaucoma Surgery

Background:

• Glaucoma filtration surgery aims to reduce intraocular pressure (IOP) by enhancing aqueous humor outflow.
• Assessing the patency and morphology of filtering blebs is crucial for surgical success.
• Anterior-segment OCT (AS-OCT) offers high-resolution cross-sectional imaging of ocular anterior segment structures.

Purpose of the Study:

• To evaluate the utility of swept-source AS-OCT in visualizing the aqueous outflow pathway.
• To assess the patency of the scleral flap in blebs following glaucoma filtration surgery.
• To correlate AS-OCT findings with surgical outcomes.

Main Methods:

• A cross-sectional study involving 205 filtering blebs from 112 patients who underwent trabeculectomy or deep sclerectomy.
• Swept-source AS-OCT was used to image blebs in sagittal and coronal planes.
• Bleb appearances were categorized based on scleral flap and sclerostomy/trabeculo-descemet window (TDW) visibility and adherence.

Main Results:

• Complete success (CS), qualified success (QS), and failure (F) rates were analyzed for trabeculectomy and deep sclerectomy cohorts.
• Category D (free scleral flap edges) was predominantly observed in successful blebs (CS).
• Category C (adherent scleral flap edges) was common in QS and failed blebs.
• Increased use of mitomycin-C (MMC) was significantly associated with categories C and D, indicating enhanced scleral flap patency.

Conclusions:

• Swept-source AS-OCT is effective for visualizing the sclerostomy/TDW and scleral flap in glaucoma surgery blebs.
• Free scleral flap edges, while correlated with MMC use, may also indicate surgical success.
• AS-OCT can complement slit-lamp examinations for comprehensive bleb assessment.