[Orbital decompression in Graves' orbitopathy-Experiences and results]

[Endocrine orbitopathy]

Endocrine orbitopathy (EO), also known as Graves' orbitopathy or thyroid-associated orbitopathy, is a self-limiting, immunologically induced co-reaction of the retrobulbar tissue of the eye triggered by an autoimmune disease of the thyroid gland. It is particularly associated with Graves' disease and is its most common extrathyroidal manifestation. In addition to typical anamnestic data, characteristic local findings and laboratory changes in immunothyroidism, orbital imaging plays a central role in the diagnosis and management of this disease. This review article provides comprehensive insight into various imaging modalities used to assess morphologic changes associated with EO. A detailed presentation of imaging findings provides a better understanding of orbital physiology.

Effects of orbital decompression on duction, cyclotorsion and diplopia

BACKGROUND

Orbital decompression is commonly performed to correct proptosis in patients with Graves' orbitopathy (GO). In literature, the incidence of new-onset constant diplopia after orbital decompression varies. Few studies have evaluated changes in duction and cyclodeviation after orbital decompression. We evaluated the changes in duction, cyclodeviation, eye position and degree of diplopia after orbital decompression.

METHODS

We retrospectively analysed data from patients who underwent orbital decompression at our hospital between January 2016 and July 2020. Data regarding the type of decompression, eye position, duction, cyclodeviation and level of diplopia according to the Gorman score were recorded.

RESULTS

Data from 281 eyes/orbits of 156 patients were analysed. Proptosis decreased from 23.8±2.5 to 20.9±2.5 mm. Horizontal and vertical duction range decreased (horizontal d=0.40 and vertical 0.30; p=0.000) after surgery; however, the change was not clinically significant (≤5°). Horizontal deviation changed towards esodeviation (d=-0.45; p=0.000), whereas vertical deviation remained stable (d=0.15; p=0.161). Preoperative cyclotorsion in the primary and downgaze positions changed towards incyclodeviation (primary: d=0.30, p=0.021; downgaze d=0.30, p=0.039). Diplopia improved in 22% (18 patients), whereas new-onset constant diplopia developed in 11% (12 patients). Elevation has an excellent predictive value of causing new-onset constant diplopia when measured preoperatively as <19°, sensitivity 88.0%, specificity 41.7% (area under the curve 0.812 (95% CI 0.660 to 0.963); p=0.000).

CONCLUSION

After orbital decompression, incidence of new-onset constant diplopia was 11% and 22% of the patients had partial or complete improvement of their diplopia. The changes in duction, cyclodeviation and horizontal deviation showed a statistical but not clinical difference. Patients with GO and a preoperatively restricted elevation of <19° are at risk of developing new-onset constant diplopia. In addition, preoperative incyclodeviation may worsen after decompression surgery.

[Diseases and Surgery of the Orbit]

Most orbital diseases are rarely diagnosed in the clinic. Because the consequences for the eye can be severe, it is important to recognize the signs of orbital disease early in order to initiate the correct diagnostic and therapeutic steps in good time. This article presents the basics of the systematics, diagnostics and therapy of orbital diseases in preparation for the specialist examination for ENT medicine. Some orbital diseases are typical manifestations of systemic diseases (e. g. Graves' disease) or typical complications of diseases in the vicinity of the orbit (e. g. orbital complications from inflammatory or tumorous sinus diseases). The diseases of the lacrimal system and the eyelids as well as their therapy are closely related to the diseases of the orbit. Basically, it can be said that the diagnosis and therapy of orbital diseases should always be carried out on an interdisciplinary basis, whereby the involvement of the ophthalmologist is of particular importance.