Flash and pattern visual evoked potentials in the diagnosis and monitoring of dysthyroid
The most acute sight-threatening condition is dysthyroid
optic neuropathy (DON), when the pressure at the orbital apex increases causing compression of the optic nerve; this results in reduced visual acuity, impaired colour vision and restriction of visual fields.
Six percent of patients with TAO develop dysthyroid
optic neuropathy (DON); compression of the optic nerve by enlarged orbital tissues in the orbital apex likely accounts for the majority of these cases (3).
Monteiro, "Imaging studies for diagnosing Graves' orbitopathy and dysthyroid
optic neuropathy," Clinics, vol.
The classification is comprised based on the severity of orbital changes ranging from mild GO, moderate-to-severe GO, to sight-threatening GO, which includes dysthyroid
optic neuropathy (DON) .
Sight threatening TED are those patients who have dysthyroid
optic neuropathy or corneal breakdown.
Virk, "Proptosis reduction by clinical vs radiological modalities and medial vs inferomedial approaches comparison following endoscopic transnasal orbital decompression in patients with dysthyroid
orbitopathy," JAMA Otolaryngology.
De Marco, "Visual evoked potentials in patients with Graves' ophthalmopathy complicated by ocular hypertension and suspect glaucoma or dysthyroid
optic neuropathy," Documenta Ophthalmologica, vol.
(4) Advanced age, systemic vascular disease, hyperviscosity, diabetes mellitus, dysthyroid
ophthalmopathy, and 360[degrees] scleral buckling surgery due to retinal detachment are among the risk factors associated with this complication.
Unilateral eyelid retraction secondary to contralateral ptosis in dysthyroid
Included in the differential diagnoses are dysthyroid
eye disease, retrobulbar orbital tumor, inflammatory pseudo tumor, sinus tumor, metastatic lesion and mucoceles of paranasal sinuses.
Two of the six patients had dysthyroid
optic neuropathy; one proved refractory to intravenous methylprednisolone and the other worsened despite orbital decompression surgery.