Before revision: Physical exertion like weight lifting and aerobic exercise, coughing, sneezing, straining at stool, vomiting, sexual intercourse, pregnancy, blowing up balloons, blowing musical instruments, cardiopulmonary resuscitation or compression injuries may cause sudden increase in intrathoracic or intra-abdominal pressure may lead to rupture of superficial retinal blood vessels.
After revision: asthma,Physical exertion like weight lifting and aerobic exercise, coughing, sneezing, straining at stool, vomiting, sexual intercourse, pregnancy, blowing up balloons, blowing musical instruments, cardiopulmonary resuscitation or compression injuries may cause sudden increase in intrathoracic or intra-abdominal pressure may lead to rupture of superficial retinal blood vessels.