UNILATERAL EXOPHTHALMOS WITH SPECIAL REFERENCE TO ENDOCRINE EXOPHTHALMOS AND PSEUDOTUMOR

Clinical features of Graves' ophthalmopathy in an incidence cohort

PURPOSE

To determine the clinical characteristics of an incidence cohort of patients with Graves' ophthalmopathy.

METHODS

We reviewed the community medical records of 120 patients residing in Olmsted County, Minnesota, in whom Graves' ophthalmopathy was diagnosed between 1976 and 1990.

RESULTS

Among 120 patients with Graves' ophthalmopathy, 108 (90%) patients had Graves' hyperthyroidism, one (1%) had primary hypothyroidism, four (3%) had Hashimoto's thyroiditis, and seven (6%) were euthyroid. At some point in their clinical course, eyelid retraction was present in 108 patients, whereas the approximate frequency of exophthalmos was 62% (73 patients); restrictive extraocular myopathy, 43% (51 patients); and optic nerve dysfunction, 6% (seven patients). Only six (5%) patients had eyelid retraction, exophthalmos, optic nerve dysfunction, extraocular muscle involvement, and hyperthyroidism. At the time of diagnosis of ophthalmopathy, upper eyelid retraction and eyelid lag were documented in 85 and 52 patients, respectively, and the most frequent ocular symptom was pain (36 patients, 30%). Diplopia was noted at the initial examination by 20 patients, lacrimation was present in 25 patients, 19 patients had photophobia, and nine patients had blurred vision. Decreased vision from optic neuropathy was present in less than 2% of eyes at the time of diagnosis. Thyroid dermopathy and acropachy accompanied Graves' ophthalmopathy in five patients (4%) and one (1%) patient, respectively. Myasthenia gravis occurred in only one patient.

CONCLUSIONS

Eyelid retraction is the most common clinical sign of Graves' ophthalmopathy. The complete constellation of typical features (hyperthyroidism, eyelid retraction, exophthalmos, restrictive extraocular myopathy, and optic nerve dysfunction) occurs relatively infrequently.

Pathogenesis of unilateral proptosis

A series of 34 patients presenting with unilateral proptosis has been studied in order to evaluate the mechanism of proptosis. It is observed that symmetrical (axial) proptosis is usually the result of generalised increase in intraorbital contents and occurs in thyroid disease and with intracranial lesions lying remote from the orbit. Rarely, in myasthenia gravis, it may be caused by myogenic paralysis of the extraocular muscles. Asymmetrical proptosis is the result of localised increase in intraorbital contents, and this occurs with expanding lesions of the orbit and in lesions arising from neighbouring structures and enroaching the orbit.