Functional Prognostic value of optical coherence tomography in optic chiasmal decompression: A preliminary study

Area of Science:

• Ophthalmology
• Neuroscience
• Medical Imaging

Background:

• Optic pathway compression, often from sellar/perisellar tumors, can lead to significant visual field deficits.
• Chiasmal decompression is a surgical intervention to relieve pressure on the optic chiasm.
• Predicting functional recovery post-decompression is crucial for patient management and visual prognosis.

Purpose of the Study:

• To evaluate the predictive capability of pre-operative Optical Coherence Tomography (OCT) measurements of the Ganglion Cell Complex Layer (GCC) and Retinal Nerve Fiber Layer (RNFL) for visual recovery.
• To establish specific OCT thresholds that indicate potential for visual improvement after chiasmal decompression surgery.

Main Methods:

• Pre-operative GCC and RNFL thickness were measured using OCT in patients with optic chiasm compression.
• Visual recovery was assessed by changes in Mean Deviation (MD) and Pattern Standard Deviation (PSD) via Humphrey visual field testing post-surgery.
• Receiver Operating Characteristic (ROC) curve analysis was employed to determine optimal predictive thresholds.

Main Results:

• Significant predictive thresholds for visual recovery were identified using OCT measurements.
• A superior GCC thickness of ≥63μm demonstrated the highest prognostic value (AUC=1) for visual improvement.
• Mean GCC ≥ 67μm and mean RNFL ≥ 75μm also exhibited strong predictive capabilities (AUC>0.9).

Conclusions:

• Pre-operative OCT measurements, particularly GCC thickness, provide significant predictive value for early visual recovery following chiasmal decompression.
• Identified OCT thresholds may aid in forecasting visual outcomes in patients with optic pathway compression.
• Further research with larger patient cohorts is recommended to validate and refine these predictive OCT thresholds.