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What is A patient presented with unilateral proptosis which was compressible and increases on bending forward. No thrill or bruit was present. MRI shows a retroorbital mass with enhancement. The likely diagnosis is- and explain in detail?
*Proptosis on bending forward is typical of intermittent proptosis. Orbital varices constitute about 90% of cases of intermittent proptosis). So, it is seen in venous malformation, i.e orbital varixes. *AV malformation and encephalocele cause pulsatile exophthalmos. Ref: Henderson's orbital tumors 2nd/e p.404