Surgical decompression in endocrine orbitopathy. Visual evoked potential evaluation and effect on the optic nerve

Area of Science:

• Ophthalmology
• Endocrinology
• Neurosurgery

Background:

• Endocrine orbitopathy (EO), a complication of Graves disease, affects orbital tissues, leading to proptosis and potentially optic neuropathy.
• Optic neuropathy in EO results from optic nerve compression within the bony orbit, causing vision loss.
• Surgical decompression is established for proptosis and diplopia, but its efficacy for optic neuropathy recovery requires further investigation.

Purpose of the Study:

• To retrospectively analyze the recovery of optic neuropathy following orbital decompression in patients with Endocrine Orbitopathy (EO).
• To evaluate the effectiveness of fat and/or orbital wall decompression in improving Visual Evoked Potentials (VEP) in EO patients with optic nerve compression.

Main Methods:

• Retrospective analysis of 10 EO patients (20 orbits) treated with fat and/or bony decompression.
• Pre- and post-operative Visual Evoked Potentials (VEP) were used to assess optic nerve function.
• Statistical analysis (Pearson chi-square test) was applied to VEP data changes.

Main Results:

• Pre-operative VEP abnormalities were noted in 10 cases for amplitude and 15 for latency.
• Post-operative VEP showed improvement, with abnormalities reduced to 6 cases for amplitude and 9 for latency.
• Orbital decompression surgery led to significant improvements in VEP amplitude and latency, indicating optic nerve recovery.

Conclusions:

• Orbital decompression, including fat and bony decompression, is vital for improving exophthalmos and diplopia in EO.
• This surgical approach serves as critical rescue therapy for optic neuropathy in severe EO cases, as evidenced by VEP improvements.
• Mandatory imaging and functional nerve evaluation (VEP) are essential for all EO patients to detect and manage optic nerve involvement.