Wide scan imaging with swept-source optical coherent tomography for glaucoma diagnosis

Area of Science:

• Ophthalmology
• Medical Imaging
• Glaucoma Diagnosis

Background:

• Glaucoma diagnosis relies on detecting structural changes in the retina.
• Optical coherence tomography (OCT) is crucial for measuring retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC) thickness.
• Differentiating between glaucoma and healthy eyes requires accurate and repeatable measurements.

Purpose of the Study:

• To compare the glaucoma-discriminating capabilities of wide-field (12x9mm) SS-OCT macular and circumpapillary RNFL (cpRNFL) thickness measurements against standard (6x6mm) scans.
• To assess if a single wide scan can replace multiple standard scans for glaucoma evaluation.

Main Methods:

• Retrospective chart review of 122 subjects (60 glaucoma, 62 healthy).
• Comparison of macular ganglion cell layer plus inner plexiform layer (mGCIPL), mGCIPL plus nerve fiber layer (mGCC), and total retinal layer (TRL) thickness from wide and standard macula scans.
• Assessment of cpRNFL thickness from wide and standard disc scans using SS-OCT.
• Evaluation of measurement repeatability and agreement using intraclass correlation coefficients (ICCs).
• Analysis of glaucoma-discriminating ability using areas under the receiver operating characteristic curves (AUCs).

Main Results:

• All parameters demonstrated high repeatability and agreement (ICCs ≥ 0.800).
• AUCs for mGCIPL thickness ranged from 0.701-0.847, and for cpRNFL thickness ranged from 0.726-0.902 across scan types.
• No significant differences in AUCs were observed between wide and standard scans for either macular or cpRNFL measurements.

Conclusions:

• Wide SS-OCT scans show excellent agreement with standard scans for mGCIPL, mGCC, and cpRNFL measurements.
• The glaucoma-discriminating ability of wide scans is comparable to that of standard macula and disc scans.
• A single wide scan can effectively replace separate standard macula and disc scans in glaucoma assessment, streamlining the diagnostic process.