In this prospective, uncontrolled study euthyroid patients with moderate to severe inactive thyroid eye disease underwent colour Doppler imaging before and after orbital decompression. Patients with dysthyroid optic neuropathy, corneal breakdown, systemic disease (diabetes, cerebrovascular accident, cardiovascular and peripheral vascular disease, unilateral or bilateral carotid artery stenosis) prior orbital decompression, and active or passive smoking in past five years were excluded. Colour Doppler imaging was performed by same radiologist preoperatively and three months postoperatively. Ophthalmic artery blood flow was measured 2cm posterior to the globe and central retinal artery was assessed within the retro-laminar part of the optic nerve. Resistance index (RI) was calculated for ophthalmic artery and central retinal artery based on the peak systolic velocity and end diastolic velocity. Maximum and minimum blood flow of the superior ophthalmic vein were also recorded. After initial recruitment of 20 patients (30 eyes), 24 eyes were finally included. All orbital flow parameters, RI of ophthalmic and central retinal arteries as well as minimum and maximum velocity of flow in the superior ophthalmic vein significantly improved after orbital decompression. It is not known whether any of the patients were on systemic steroids. The authors discuss that the flow parameters are higher preoperatively secondary to compression mechanism rather than an inflammatory mechanism in these cases with inactive thyroid eye disease. Even though an interesting finding, the clinical value of colour Doppler imaging in thyroid eye disease patients is not justified with this study.