Quantitative assessment of optic nerve head pallor

Area of Science:

• Ophthalmology
• Neuroscience
• Medical Imaging

Background:

• Optic nerve head pallor is a symptom of anterior ischaemic and glaucomatous optic neuropathy.
• These conditions involve neural tissue loss, glial cell activation, and tissue remodeling.
• Accurate measurement of optic disc pallor is crucial for diagnosis and management.

Purpose of the Study:

• To develop and validate a simple method for measuring optic disc pallor.
• To assess the reproducibility and variability of the pallor measurement technique.
• To evaluate the utility of optic disc pallor measurement in detecting and monitoring optic neuropathy.

Main Methods:

• Utilized a fundus camera with a colour CCD camera and a dual bandpass filter.
• Measured optic disc pallor in healthy subjects and patients with optic neuropathy.
• Assessed reproducibility through repeated measurements in the same subject and variation across healthy subjects.

Main Results:

• The method demonstrated good reproducibility with a coefficient of variation of 11.7% for repeated measurements.
• Variation among six healthy subjects was 14.8%.
• Significantly increased optic disc pallor was observed in atrophic discs compared to contralateral eyes and in clinically unaffected eyes compared to healthy controls.

Conclusions:

• Optic disc pallor measurement using the described fundus camera method is reproducible.
• The technique shows potential for early detection of optic neuropathy.
• This method may be valuable for the follow-up of patients with optic neuropathy.