Extracranial orbital decompression for optic neuropathy in Graves' eye disease

Area of Science:

• Ophthalmology
• Endocrinology
• Neurology

Background:

• Graves' eye disease (Graves' ophthalmopathy) can cause optic neuropathy due to enlarged extraocular muscles compressing the optic nerve.
• Corticosteroids, irradiation, and surgical orbital decompression are established treatments for Graves' optic neuropathy.
• Extracranial orbital decompression is a surgical option for managing optic nerve compression in Graves' disease.

Purpose of the Study:

• To evaluate the effectiveness of extracranial orbital decompression in treating Graves' optic neuropathy.
• To assess changes in visual acuity, color vision, and proptosis following the procedure.
• To analyze the impact on extraocular muscle imbalance and diplopia.

Main Methods:

• Retrospective analysis of 21 patients (33 orbits) undergoing extracranial orbital decompression by a single surgeon.
• Assessment of visual acuity and color vision at 4 weeks postoperatively and during follow-up.
• Measurement of proptosis reduction and evaluation of extraocular muscle function and diplopia status.

Main Results:

• Short-term improvement in visual acuity and color vision in all 33 eyes.
• Sustained visual improvement in most patients, with a small percentage experiencing later deterioration.
• Significant reduction in proptosis (mean 5.0 mm).
• Increased incidence or worsening of diplopia in 43% of patients, particularly with medial wall decompression.
• Diplopia was successfully managed with subsequent squint surgery in affected patients.

Conclusions:

• Extracranial orbital decompression is effective for improving vision and reducing proptosis in Graves' optic neuropathy.
• A significant proportion of patients experience worsening or new-onset diplopia.
• Surgical decompression involving the lateral wall may reduce the risk of postoperative diplopia.
• Diplopia, when it occurs, is generally manageable with further surgical intervention.