PurposeTo present the clinical features of thyroid-associated ophthalmopathy (TAO) with different CT types, and to report the outcomes of endoscopic orbital decompression combined with fat decompression (EOD-FD).Patients and methodsThirty-four patients with TAO who underwent EOD-FD between December 2020 and March 2022 in the Ophthalmology Department of Li Huili Hospital Affiliated with Ningbo University, were included in this retrospective interventional case series. Patients were categorized into two groups based on the results of computerized tomography (CT) scans: muscle expansion type and fat hyperplasia type.ResultsThirty-four TAO patients (55 eyes) were included in this study, and the mean age was 38.62 years (range 22–60 years). The average eye protrusion (EP) reduced from preoperative 23.20 mm to postoperative 19.66 mm (p< 0.0001). Mean intraocular pressure (IOP) decreased from 20.11 mmHg at baseline to 17.29 mmHg postoperatively (p< 0.0001), with a reduction of 2.84 mmHg (14.12%). Twenty cases of muscle expansion and fourteen cases of fat hyperplasia were definite by CT imaging. The mean IOP in the muscle expansion group was higher than that in the fat hyperplasia group (p< 0.05). Elevated intraocular pressure (IOP) occurred in 23 eyes (36.11%), and it was associated with extraocular muscle involvement, gender, and EP. In 3 cases of impaired vision, the mean best corrected visual acuity (VA) improved from 0.4 preoperatively to 0.84 postoperatively (p< 0.01). There were 8 cases with visual field (VF) damage and/or corneal epithelium damage, and all these damages were reversible.ConclusionIn this study, we describe the clinical features and experience of EOD-FD in patients with TAO. EOD-FD is an effective technique in reducing IOP and proptosis, with a low incidence of postoperative diplopia.