<prompt> A patient presented with unilateral proptosis which was and increases on bending forward. No thrill or bruit was present. MRI shows a retroorbital mass with enhancement. The likely diagnosis is -AV malformationsOrbital encephalocoecleOrbital varixNeurofibromatosis  <response>: All are features of Orbital varix. Other circulatory disorders causing unilateral proptosis : angioneurotic edema, Orbital aneurysm. Ref: AK Khurana 6thE pg404 Img ref 