Intraocular Pressure Lowering Effect of Orbital Decompression is Related to Increased Venous Outflow in Graves Orbitopathy. (July 2014)

• Record Type: Journal Article
• Authors: Onaran, Zafer; Konuk, Onur; Oktar, Suna Özhan; Yücel, Cem; Ünal, Mehmet
• Is Part Of: Current eye research. Volume 39:Number 7(2014:Jul.)
• Page Start: 666
• Page End: 672
• Publication Date: 2014-07
• Subjects: Ophthalmology -- Periodicals; Eye -- Diseases -- Periodicals; Ophthalmology -- Periodicals; 573.88
• DOI: 10.3109/02713683.2013.867355
• Languages: English
• ISSNs: 0271-3683

Abstract

<abstract> <title>Abstract</title> <p> <italic>Purpose:</italic> To investigate the effects of combined orbital bone and fat decompression on intraocular pressure (IOP) and superior ophthalmic vein blood flow velocity (SOV-BFV), and their association with the clinical features of Graves orbitopathy (GO).</p> <p> <italic>Methods:</italic> During the 2002–2008 period, 72 eyes of 36 GO cases demonstrating moderate to severe orbitopathy were evaluated according to their clinical features as: cases with or without dysthyroid optic neuropathy (DON), and underwent orbital decompression. A control group comprised 40 eyes of 20 healthy subjects. In both groups, a full ophthalmic examination including IOP and Hertel measurements was performed, and SOV-BFV was analyzed with color Doppler imaging. Examinations were repeated after orbital decompression in GO patients.</p> <p> <italic>Results:</italic> All the cases demonstrated clinical features of inactive disease. Among the patients 24 of 72 eyes (33.3%) showed clinical features of DON. After surgery, the mean decrease in Hertel values was 6.2 ± 1.8 mm (<italic>p</italic> = 0.001). The mean decrease in IOP was 3.0 ± 1.7 mmHg (from 17.3 ± 2.7 to 14.3 ± 2.0 mmHg) after orbital decompression where the post-operative values were comparable with the control group (12.9 ± 1.4 mmHg, <italic>p</italic> = 0.36). The mean increase in SOV-BFV achieved with decompression was 1.2 ± 0.6 cm/s (from 4.8 ± 1.7 to 6.0 ± 1.8 cm/s) and post-operative SOV-BFV values were also comparable with the control group (6.6 ± 1.3 cm/s, <italic>p</italic> = 0.26). The increase in SOV-BFV in cases with DON did not differ from cases without DON (<italic>p</italic> = 0.32), however, post-operative SOV-BFV of cases with DON was stil lower than cases without DON (<italic>p</italic> = 0.035).</p> <p> <italic>Conclusions:</italic> Combined orbital bone and fat decompression significantly reduced the IOP levels and increased the SOV-BFV in GO. This could be the confirmative finding of prediction that elevated IOP in GO is associated with increased episcleral venous pressure. The post-operative changes in IOP and SOV-BFV show differences regarding the clinical features of disease.</p> </abstract>