Orbital compliance in Graves' eye disease

Thirty-three patients with Graves' eye disease (GED) and 68 normal subjects had their orbital compliance measured by determining the force generated on retropulsing the eye and also estimated on digital retropulsion, and their eye position determined with an exophthalmometer. Patients with compressive optic neuropathy showed significantly higher mean forward force on retropulsion than other Graves' eye disease patients or normal subjects, supporting the theory that the tissue is compressed in these orbits. There is a suggestion that orbital compliance testing of a GED patient without compressive optic neuropathy may be of value in predicting the risk of the patient developing compressive optic neuropathy. There is no association between the force on ocular retropulsion and the exophthalmometer reading. The digital estimation of the resistance to retropulsion did not reliably suggest the measured forces.