Automated macular segmentation can distinguish glaucomatous from compressive optic neuropathy

Area of Science:

• Ophthalmology
• Neuro-ophthalmology
• Medical Imaging

Background:

• Glaucomatous optic neuropathy (GON) and compressive optic neuropathy (CON) are distinct conditions affecting the optic nerve.
• Differentiating between GON and CON is crucial for appropriate patient management and treatment.
• Macular structure alterations may offer insights into optic nerve pathologies.

Purpose of the Study:

• To compare macular damage in patients with GON and CON.
• To evaluate the diagnostic accuracy of spectral-domain optical coherence tomography (SD-OCT) in distinguishing between GON and CON.

Main Methods:

• An observational, cross-sectional study included patients with GON, CON, and healthy controls.
• An automated SD-OCT algorithm segmented the circumpapillary retinal nerve fiber layer (cpRNFL) and macula.
• Macular layer thickness was measured and compared across groups using standardized grids.

Main Results:

• Macular thickness in the ganglion cell complex was reduced in both GON and CON patients compared to controls.
• Nasal-inferior (NI) and nasal-superior sectors, along with NI/temporal inferior (TI) damage ratios in macular ganglion cell (mGCL) and inner plexiform (IPL) layers, best distinguished GON from CON.
• Combining NI sector and NI/TI damage ratios in both layers demonstrated high discriminative power (AUC 0.909).

Conclusions:

• Macular segmented layer evaluation using SD-OCT is a valuable tool for the differential diagnosis of GON and CON.
• SD-OCT analysis of macular damage can supplement existing diagnostic methods.
• This approach aids in distinguishing between these two optic neuropathies.