pressure alopecia

pres·sure al·o·pe·ci·a

loss of hair over a circumscribed area usually on the posterior scalp, resulting from the continuous pressure on the occiput in a lengthy operative procedure, or unconsciousness following a drug overdose. Synonym(s): postoperative pressure alopecia

pres·sure al·o·pe·ci·a

(presh'ŭr al'ō-pē'shē-ă) Loss of hair over a circumscribed area, usually on the posterior scalp, resulting from the continuous pressure on the occiput in a lengthy operative procedure, or unconsciousness following a drug overdose.