Perineural optic nerve changes in endocrine orbitopathy
H. W. Skalka
A-scan ultrasonographic measurements of the differences between nerve and
dural diameters of the retrobulbar optic nerve were made in 55 eyes of 30
patients with endocrine orbitopathy. This measurement was found to be
enlarged in all cases. Extraocular muscle thickness measurements were also
made ultrasonically in these eyes, and the degree of intervaginal
distension was found to increase with increasing extraocular muscle
involvement. These findings were consistent whether the patients were
hyperthyroid, hypothyroid, or euthyroid clinically, and the findings
occurred in the absence of any detectable functional optic nerve
compromise. The cause of this subdural perineural enlargement remains
unknown.
