ABSTRACT
BACKGROUND: Endoscopic orbital decompression is a well-established technique for Graves orbitopathy treatment. AIMS: Measurement of the ethmoid volume and its correlation with proptosis reduction in patients undergoing endoscopic orbital decompression for Graves' orbitopathy. METHODS: We retrospectively reviewed clinical charts of 209 patients (319 orbits) operated by a surgeon at our institution between 1998 and 2019. RESULTS: Average age was 46.9 years. About 83.3% of the patients were female, 54.6% were smokers, 93.8% were euthyroid at the time of decompression, 3.8% were hypothyroid and 2.4% were hyperthyroid. About 77.5% of the patients underwent bilateral surgery, the remainder and unilateral. Subsequent stages included strabismus surgery in 22.5% patients, Müllerectomy 37.8%, with or without canthoplasty (14.8 vs. 23%). Mean proptosis reduction was 4.61 mm. Mean ethmoid volume was 5.57 mm3. Ethmoid volume had a moderate positive correlation with proptosis reduction (r s = 0.49, p < .001). Further investigation, statistically significant moderate correlation was found only in the small (SE) and big (BE) ethmoid groups. CONCLUSION: We advise evaluating ethmoid sinus pneumatization on computed tomography before decompression to estimate possible anatomical limitations. Additional wall decompression might be advocated in most severe cases.