Comparison of transconjunctival and transnasal approaches for orbital decompression: a randomized controlled trial

This randomized controlled trial aimed to compare the effectiveness of two surgical approaches to endoscopic orbital decompression for thyroid-associated ophthalmopathy (TAO). In total, 48 moderate-to-severe or sight-threatening TAO orbits were enrolled and randomly assigned into the transconjunctival group or transnasal group. The main outcome was the rate of effectiveness. If the postoperative proptosis was below 18 mm or the value of proptosis reduction was over 8 mm, this was defined as effective. The secondary outcomes included surgical accuracy, best-corrected visual acuity (BCVA), ocular motility grade, diplopia grade, and safety. The effective rate was 87.5 % in the transconjunctival group and 79.2 % in the transnasal group (p = 0.087). The proptosis reduction was 5.38 ± 2.60 mm in the transconjunctival group and 4.40 ± 1.66 mm in the transnasal group (p = 0.435). A significant difference was found between preoperative and postoperative proptosis in both groups (p < 0.01). A higher surgical accuracy in the medial wall was found in the transconjunctival group (p = 0.001). There was no significant difference in both groups between preoperative and postoperative BCVA and ocular motility grade. Complications showed no significant difference between the two groups (p > 0.05). In conclusion, both transconjunctival and transnasal endoscopic orbital decompression were feasible and could be utilized by surgeons. This study was registered with the Chinese clinical trial registry (trial registration number: ChiCTR-INR-17013268; date of access and registration: November 3, 2017).