a flowering plant whose stem above ground does not become woody. 2. such a plant when valued for its medicinal properties, flavor, scent, or the like. 3. Often, the herb. Slang. marijuana.
Retinal detachment is a disorder of the eye in which the retina peels away from its underlying layer of support tissue.Initial detachment may be localized or broad, but without rapid treatment the entire retina may detach, leading to vision loss and blindness. It is almost always classified as a medical emergency.Permanent damage may occur if the detachment is not repaired within 24â72 hours.nitial detachment may be localized or broad, but without rapid treatment the entire retina may detach, leading to vision loss and blindness. It is almost always classified as a medical emergency. Permanent damage may occur if the detachment is not repaired within 24â72 hours.
Types. 1  Rhegmatogenous retinal detachment â A rhegmatogenous retinal detachment occurs due to a break in the retina (called a retinal tear) that allows fluid to pass from the vitreous space into the subretinal space between the sensory retina and the retinal pigment epithelium. Retinal breaks are divided into three types â holes, tears and dialyses.