Purpose: This study measured direct orbital tension (DOT) in normal and fractured orbits of Chinese patients before and after orbital fracture repair, to investigate the changes in DOT and intraocular pressure (IOP) after surgery and to evaluate any correlation between them.
Materials and methods: DOT was directly measured by a specially designed orbitonometer before and after orbital fracture surgery in 40 cases of unilateral orbital fractures, using the contralateral eyes as a control group. All of the patients were submitted to orbital fracture repair and globe repositioning. IOP and ocular function were recorded preoperatively and postoperatively.
Results: DOT was 5.0 +/- 1.3 mm Hg (mean +/- SD) in the normal orbits. DOT was positively correlated with IOP (r = 0.56; P < .01). DOT and IOP were significantly decreased (s = 81, P = .01 and s = 49.5, P = .02, respectively) on the fractured orbit side. Postoperative DOT and IOP were significantly increased (s = 410, P < .01 and s = 390, P < .01, respectively). The preoperative to postoperative changes in both DOT and IOP were positively correlated (r = 0.54; P < .01).
Conclusions: DOT can be measured safely using an orbital manometer in normal and fractured orbits. DOT and IOP increased significantly after orbital fracture surgery. DOT was well-correlated with IOP both preoperatively and postoperatively.