orbital veins

orbital veins

[TA]
the veins located within the orbits, consisting of the ophthalmic veins and their tributaries.
Synonym(s): venae orbitae [TA]
References in periodicals archive ?
The periosteum is loosely attached to the orbital bones, especially the orbital roof, which is the most common site for NTSOH development (6) The orbital veins are valveless, allowing increased jugular venous pressure to be transmitted to the veins in the subperiosteal orbital space, possibly causing rupture (2) Therefore, factors that increase venous pressures, such as vomiting, coughing and the Valsalva manoeuvre may play a major role in NTSOH (1).
Two vascular features of orbital venous malformations play a role in the lesion's characteristic appearance: (1) an absence of valves in the orbital veins and (2) a low degree of intrinsic blood flow.