Periphlebitis of the Superior Ophthalmic Vein in Noninflammatory Thyroid Eye Disease

A 32-year-old female with euthyroid Graves’ disease presented with right-sided proptosis, first noticed 3 months prior to consultation. Although she was euthyroid, her thyroid-stimulating receptor antibodies were positive. An orbital CT scan, requested by her general ophthalmologist, demonstrated an inflammatory lesion involving the right superior muscle complex. On examination, visual acuity was 20/20 in OU. Margin reflex distances were 7 mm in the OD and 5 mm in the OS (panel A). Hertel exophthalmometry measured 22 mm in OD and 14 mm in OS (panel B). No clinical inflammatory signs were detected, with both VISA (vision, inflammation, strabisumus and appearance) and CAS (clinical activity score) inflammation scores graded as zero in OU. Intraocular pressure was asymmetric, measuring 19 mm Hg in the proptotic eye and 12 mm Hg in OS. Fundus examination was normal in OU. Axial T1-weighted postcontrast magnetic resonance imaging of the orbits with fat saturation revealed periphlebitis of the right superior orbital vein, characterized by a poorly defined, enhancing inflammatory process surrounding the vein (panel C). Color Doppler ultrasonography showed reduced flow velocity in OD (3.8 cm/s vs. 5.97 cm/s in OS) (panel D). Periphlebitis of the superior orbital vein is a rare manifestation of thyroid eye disease, usually associated with the active form of the orbitopathy. The present case highlights that superior orbital vein periphlebitis in thyroid eye disease may reduce orbital venous flow without the classic conjunctival signs of venous impedance or clinical signs of disease activity.FIG.