Acute meibomitis causes increasing subjective and objective symptoms as the outer canthus is approached by the involved meibomian gland. The reason for this is that there is a confluence of nerves and bloodvessls at the outer angle. In addition, the tissues are more taut and less giving. A pressure is built up in the area with resultant pressure on the nerves and pressure on the bloodvessels. The former pressure gives pain, the latter gives edema of the more easily distended bulbar conjunctiva and skin of the lids. At times there may be collateral edema of the lids of the other eye.
There is exquisite tenderness to finger pressure over the area just above the outer canthus. There is lid edema. There is marked chemosis .