Avulsed retinal veins without retinal breaks.

A localized segment of a retinal vein can be avulsed or torn from the retina by vitreous traction without a concurrent retinal break or tear. Eight eyes in eight patients (five women and three men, 20 to 69 years old) with avulsed retinal veins without retinal breaks showed a wide range of underlying retinal abnormalities, including background diabetic retinopathy, pars planitis, and involutional proliferative retinopathies. Such avulsed retinal veins often cause recurrent vitreous hemorrhage. Despite vitreous hemorrhages in six of the eight eyes, the visual prognoses were excellent in all eyes. An avulsed retinal vein must be considered in the differential diagnosis of those patients with proliferative retinopathies who have vitreous hemorrhage.